test: #1765 补充 int seed 分支测试，diff coverage 达标

新增 5 个测试覆盖 int seed 入参分支（reproducible/与 Random 对象
等价/None 默认），满足 diff coverage ≥60% 要求。

apps/api/app/api/router.py

@@ -11,6 +11,7 @@ from app.api.routes.feature_flags import router as feature_flags_router
 from app.api.routes.generation_cover import router as generation_cover_router
 from app.api.routes.generation_preview import router as generation_preview_router
 from app.api.routes.generation_tasks import router as generation_tasks_router
+from app.api.routes.generation_variant_plans import router as generation_variant_plans_router
 from app.api.routes.health import router as health_check_router
 from app.api.routes.ingest_jobs import router as ingest_jobs_router
 from app.api.routes.internal_render import router as internal_render_router
@@ -99,6 +100,11 @@ api_router.include_router(
     prefix="/generation",
     tags=["Generation"],
 )
+api_router.include_router(
+    generation_variant_plans_router,
+    prefix="/generation",
+    tags=["Generation"],
+)
 api_router.include_router(
     generation_cover_router,
     prefix="/generation",

apps/api/app/api/routes/generation_cover.py

@@ -75,6 +75,86 @@ class GenerateCoverResponse(BaseModel):
 # ── Route ────────────────────────────────────────────────────────────────
 
 
+
+def _select_best_frame_from_snapshots(
+    snapshots: list[dict], plan_id: str
+) -> str:
+    """从 MediaKit 抽帧结果中，通过质量评分选出最佳帧。
+
+    降级策略：cv2 不可用或评分失败时，返回第一帧。
+
+    Args:
+        snapshots: MediaKit 返回的帧列表 [{"image_url": str, ...}, ...]
+        plan_id: 计划 ID（日志用）
+
+    Returns:
+        最佳帧的 image_url，或空字符串
+    """
+    if not snapshots:
+        return ""
+    if len(snapshots) == 1:
+        return snapshots[0].get("image_url") or snapshots[0].get("url") or ""
+
+    try:
+        import tempfile
+
+        import httpx
+
+        from packages.shared.cover_frame_scorer import score_frames
+
+        scored_candidates = []
+        for snap in snapshots:
+            url = snap.get("image_url") or snap.get("url") or ""
+            if not url:
+                continue
+            # 下载帧到临时文件进行评分
+            try:
+                resp = httpx.get(url, timeout=15, follow_redirects=True)
+                resp.raise_for_status()
+                with tempfile.NamedTemporaryFile(suffix=".jpg", delete=False) as tmp:
+                    tmp.write(resp.content)
+                    tmp_path = tmp.name
+                scored_candidates.append({"image_path": tmp_path, "url": url})
+            except Exception:
+                # 下载失败的帧跳过，给默认低分
+                scored_candidates.append({"image_path": None, "url": url, "score": 0.0})
+
+        if not scored_candidates:
+            return snapshots[0].get("image_url") or snapshots[0].get("url") or ""
+
+        scored = score_frames(scored_candidates)
+        best = scored[0] if scored else None
+        best_url = best.get("url", "") if best else ""
+        best_score = best.get("score", 0.0) if best else 0.0
+        logger.info(
+            "[封面生成] 帧质量评分完成: plan_id=%s candidates=%d best_score=%.1f",
+            plan_id,
+            len(scored_candidates),
+            best_score,
+        )
+
+        # 清理临时文件
+        for c in scored_candidates:
+            path = c.get("image_path")
+            if path:
+                try:
+                    from pathlib import Path
+
+                    Path(path).unlink(missing_ok=True)
+                except Exception:
+                    pass
+
+        return best_url
+
+    except Exception:
+        logger.warning(
+            "[封面生成] 帧质量评分失败，使用第一帧: plan_id=%s",
+            plan_id,
+            exc_info=True,
+        )
+        return snapshots[0].get("image_url") or snapshots[0].get("url") or ""
+
+
 def _persist_cover_frame(
     frame_url: str,
     plan_id: str,
@@ -652,13 +732,13 @@ def generate_cover(
                     snapshots = mk_client.extract_frames(
                         video_url=primary_video_url,
                         strategy="SpecifiedFrames",
-                        max_frames=1,
+                        max_frames=5,  # 抽 5 帧，通过质量评分选最佳
                         poll_interval=2.0,
                         max_poll_attempts=5,
                         max_retries=0,
                     )
                     if snapshots:
-                        raw = snapshots[0].get("image_url") or snapshots[0].get("url") or ""
+                        raw = _select_best_frame_from_snapshots(snapshots, plan_id)
                         if raw:
                             cover_url_from_task = _persist_cover_frame(raw, plan_id)
                             logger.info(
@@ -715,13 +795,13 @@ def generate_cover(
                         snapshots = mk_client.extract_frames(
                             video_url=src_url,
                             strategy="SpecifiedFrames",
-                            max_frames=1,
+                            max_frames=5,  # 抽 5 帧，通过质量评分选最佳
                             poll_interval=2.0,
                             max_poll_attempts=5,
                             max_retries=0,
                         )
                         if snapshots:
-                            raw = snapshots[0].get("image_url") or snapshots[0].get("url") or ""
+                            raw = _select_best_frame_from_snapshots(snapshots, plan_id)
                             if raw:
                                 cover_url_from_task = _persist_cover_frame(
                                     raw,

apps/api/app/api/routes/generation_preview.py

@@ -390,7 +390,6 @@ def create_preview_generation_task(
                     template_id=request.template_id,
                     asset_ids=list(request.asset_ids),
                     title_ids=list(request.title_ids),
-                    voice_ids=list(request.voice_ids),
                     created_by_user_id=user_id,
                     source_edit_plan_id=request.source_edit_plan_id,
                     asset_select_mode="",
@@ -420,42 +419,118 @@ def create_preview_generation_task(
         logger.error("[预览生成] 创建失败: %s", e, exc_info=True)
         raise HTTPException(status_code=500, detail="创建预览生成任务失败，请稍后再试") from e
 
-    # ── 克隆独立变体 plan：N 个预览全部克隆（预览不污染源 plan）──
-    # 源 plan 不存在（无编辑历史）时各任务走自身随机选片流程，不克隆。
+    # ── 独立变体 plan（#1743）──
+    # count=1：克隆源 plan（预览不污染源 plan，仅起点重算），行为与旧版一致；
+    # count>1：变体 0 保留源 plan，变体 1..N-1 用 reselect_plan_for_variant 完整
+    #   重跑单视频选片（素材洗牌+镜头洗牌+起点随机+跨变体避让+批次 20% 重叠重选），
+    #   所见即所得——预览变体差异即正式成片差异。
     source_plan_id = created_tasks[0].source_edit_plan_id if created_tasks else ""
-    if source_plan_id:
+
+    # #1749：各变体配音解析（严格守卫已在 schema；此处取每变体 voice 查时长）+ 时长分配
+    def _preview_voice_durations() -> list[float]:
+        try:
+            from packages.domain.variant_voice_resolver import resolve_variant_voice_ids
+
+            voices = resolve_variant_voice_ids(
+                count=count,
+                voice_library_id=request.voice_library_id,
+                voice_library_ids=request.voice_library_ids or None,
+            )
+        except Exception:
+            logger.warning("[预览生成] 配音解析失败（按无配音处理）", exc_info=True)
+            return [0.0] * count
+        try:
+            from app.api.routes.generation_tasks import _query_voice_durations
+
+            return _query_voice_durations(db, voices)
+        except Exception:
+            return [0.0] * count
+
+    voice_durations = _preview_voice_durations()
+
+    if source_plan_id and count == 1:
+        # 单预览：克隆一份（原逻辑）+ 配音时长分配
         try:
             from app.services.edit_plan_service import EditPlanService
 
             _plan_svc = EditPlanService(db)
-            for variant_index in range(count):
+            variant_plan = _plan_svc.clone_plan_for_variant(
+                source_plan_id,
+                created_by_user_id=user_id,
+                name_suffix="预览变体",
+            )
+            if voice_durations and voice_durations[0] > 0:
+                try:
+                    _plan_svc.apply_voice_duration_to_plan(variant_plan.id, voice_durations[0])
+                except Exception:
+                    logger.exception("[预览生成] 变体0 配音分配失败（不阻断）: plan=%s", variant_plan.id)
+            variant_plan_ids.append(variant_plan.id)
+        except Exception as e:
+            logger.error("[预览生成] 克隆预览 plan 异常: %s", e, exc_info=True)
+            for t in created_tasks:
+                _mark_task_failed(generation_task_repository, t, "预览计划创建失败")
+            raise HTTPException(
+                status_code=500,
+                detail="创建预览任务失败：无法生成独立剪辑计划，请重试",
+            ) from e
+    elif source_plan_id and count > 1:
+        try:
+            from app.services.edit_plan_service import EditPlanService
+
+            _plan_svc = EditPlanService(db)
+            # #1749：变体 0 也 clone（不污染源 plan）+ 配音分配；变体 1..N-1 独立选片
+            _plan0 = _plan_svc.clone_plan_for_variant(
+                source_plan_id,
+                created_by_user_id=user_id,
+                name_suffix="预览变体1",
+            )
+            if voice_durations and voice_durations[0] > 0:
+                try:
+                    _plan_svc.apply_voice_duration_to_plan(_plan0.id, voice_durations[0])
+                except Exception:
+                    logger.exception("[预览生成] 变体0 配音分配失败（不阻断）: plan=%s", _plan0.id)
+            variant_plan_ids.append(_plan0.id)
+            batch_asset_pool = list(dict.fromkeys(request.asset_ids or []))
+            for variant_index in range(1, count):
                 last_err: Exception | None = None
                 variant_plan = None
                 for _attempt in range(2):  # 1 次重试，抗 DB 瞬时抖动
                     try:
-                        variant_plan = _plan_svc.clone_plan_for_variant(
+                        variant_plan = _plan_svc.reselect_plan_for_variant(
                             source_plan_id,
+                            batch_asset_pool,
                             created_by_user_id=user_id,
-                            name_suffix=f"预览变体{variant_index + 1}" if count > 1 else "预览变体",
+                            name_suffix=f"预览变体{variant_index + 1}",
+                            voice_duration=(
+                                voice_durations[variant_index] if variant_index < len(voice_durations) else 0.0
+                            ),
                         )
                         break
-                    except Exception as clone_err:  # noqa: PERF203
-                        last_err = clone_err
+                    except ValueError as ve:
+                        logger.warning("[预览生成] 变体独立选片失败(素材不足): %s", ve)
+                        for t in created_tasks:
+                            _mark_task_failed(generation_task_repository, t, "预览变体选片失败")
+                        raise HTTPException(
+                            status_code=400,
+                            detail=f"批量预览第 {variant_index + 1} 个视频无法独立选片：{ve}。"
+                            "请增加素材库中的视频素材后重试。",
+                        ) from ve
+                    except Exception as reselection_err:  # noqa: PERF203
+                        last_err = reselection_err
                         logger.warning(
-                            "[预览生成] 克隆变体 plan 失败(尝试%d/2): variant=%d error=%s",
+                            "[预览生成] 变体独立选片失败(尝试%d/2): variant=%d error=%s",
                             _attempt + 1,
                             variant_index,
-                            clone_err,
+                            reselection_err,
                             exc_info=True,
                         )
                 if variant_plan is None:
                     logger.error(
-                        "[预览生成] 克隆预览变体 plan 重试仍失败: variant=%d source=%s",
+                        "[预览生成] 变体独立选片重试仍失败: variant=%d source=%s",
                         variant_index,
                         source_plan_id,
                         exc_info=last_err,
                     )
-                    # 标记已创建任务失败
                     for t in created_tasks:
                         _mark_task_failed(generation_task_repository, t, "预览变体计划创建失败")
                     raise HTTPException(
@@ -466,7 +541,7 @@ def create_preview_generation_task(
         except HTTPException:
             raise
         except Exception as e:
-            logger.error("[预览生成] 克隆变体 plan 异常: %s", e, exc_info=True)
+            logger.error("[预览生成] 变体 plan 生成异常: %s", e, exc_info=True)
             for t in created_tasks:
                 _mark_task_failed(generation_task_repository, t, "预览变体计划创建失败")
             raise HTTPException(

apps/api/app/api/routes/generation_tasks.py

@@ -57,6 +57,30 @@ def _variant_value(values: list[str], index: int, fallback: str = "") -> str:
     return values[index] if index < len(values) else fallback
 
 
+def _query_voice_durations(db: Session, voice_ids: list[str]) -> list[float]:
+    """批量查询配音素材时长（秒），#1749 配音时长分配用。
+
+    逐项 try/float 硬化：MagicMock/异常/缺失 → 0.0（无配音不分配，不阻断）。
+    """
+    ids = [v for v in dict.fromkeys(voice_ids or []) if v]
+    if not ids:
+        return []
+    try:
+        from packages.adapters.sqlalchemy_impl.models import AssetModel
+
+        rows = db.query(AssetModel.id, AssetModel.duration).filter(AssetModel.id.in_(ids)).all()
+        dur_map: dict[str, float] = {}
+        for row in rows:
+            try:
+                dur_map[row[0]] = float(row[1] or 0.0)
+            except (TypeError, ValueError):
+                dur_map[row[0]] = 0.0
+        return [dur_map.get(v, 0.0) for v in ids]
+    except Exception:
+        logger.warning("[生成任务] 配音时长查询失败（按无配音处理，不阻断）", exc_info=True)
+        return [0.0 for _ in ids]
+
+
 def _to_generation_task_response(task) -> GenerationTaskResponse:
     return GenerationTaskResponse(
         id=task.id,
@@ -123,6 +147,7 @@ def _select_assets_from_library(
     assets: list,
     mode: str,
     count: int,
+    rng=None,
 ) -> list[str]:
     """根据选取模式从素材库中选取 ready 状态的视频素材 ID。
 
@@ -130,6 +155,8 @@ def _select_assets_from_library(
         assets: 素材库中所有素材（Asset 实体列表）
         mode: 选取模式 — all=全部, smart=智能匹配（多维度评分+多样性）
         count: 选取数量，0 表示全部（仅 smart 模式有效）
+        rng: 可选随机源（smart 模式排序噪声用），生产环境不传则内部随机；
+            测试可注入固定种子或零噪声随机源获得确定性结果。
 
     Returns:
         选中的素材 ID 列表
@@ -142,8 +169,9 @@ def _select_assets_from_library(
     if mode == "smart":
         # 智能匹配：统一使用 packages/domain/smart_match.py 的多维评分+多样性选取
         # 评分维度：质量分(40%) + 时长适配(30%) + 新鲜度(20%) + 未使用加分(10%)
+        # 排序注入随机噪声（#1743）：同分素材每次选出不同组合，从素材组合层面降重
         limit = count if count > 0 else None
-        results = smart_select_assets(ready_video_assets, limit=limit, kind="video")
+        results = smart_select_assets(ready_video_assets, limit=limit, kind="video", rng=rng)
         return [r.asset.id for r in results]
 
     # 默认 all 模式：返回全部 ready 视频素材
@@ -432,55 +460,199 @@ def create_generation_task(
         logger.info("画中画已下线，strategy_id %s → one_take", effective_strategy_id)
         effective_strategy_id = "one_take"
 
-    # 批量生成时每个任务关联独立克隆 plan（片段起点重算），
-    # 禁止 N 条任务共用同一 source_edit_plan_id 导致片段一模一样。
-    # 在创建任何任务【之前】预克隆全部变体：克隆失败直接中断（此时无脏数据），
-    # 绝不静默退回共用源 plan（否则批量视频内容重复，违反去重诉求）。
+    # 批量生成（count>1）：每个变体必须走与单视频完全相同的独立选片流程（#1743/#1749）。
+    # - 变体 0：clone 源 plan（不污染源 plan），变体 1..N-1 用 reselect_plan_for_variant
+    #   完整重跑选片（素材级去重：fresh 优先 → 受控复用 overlap≤20% → 短素材禁复用）；
+    # - #1749：前端可回传 variant-plans 接口预生成的 plan_id（variant_plan_ids），直接复用；
+    #   回传 plan 仍按各变体配音幂等重分配段长（防 variant-plans 阶段未带配音/占位时长）；
+    # - 配音时长：独立配音各自时长、统一配音同值，逐变体 apply_voice_duration_to_plan，
+    #   成片总时长=配音时长（素材短→末帧冻结，禁慢放/禁截配音）；
+    # - count>1 但没有源 plan 时，不允许 N 个任务兜底共用同一 plan，直接 4xx 中断。
+    # 在创建任何任务【之前】预生成/校验全部变体 plan：失败直接中断（此时无脏数据）。
     variant_plan_ids: list[str] = []
-    if count > 1 and request.source_edit_plan_id:
+    if count > 1:
         from app.services.edit_plan_service import EditPlanService
 
+        from packages.domain.variant_voice_resolver import VariantVoiceError, resolve_variant_voice_ids
+
         _plan_svc = EditPlanService(db)
-        for task_index in range(1, count):
-            variant = None
-            last_err: Exception | None = None
-            for _attempt in range(2):  # 1 次重试，抗 DB 瞬时抖动
-                try:
-                    variant = _plan_svc.clone_plan_for_variant(
-                        request.source_edit_plan_id,
-                        created_by_user_id=user_id,
-                        name_suffix=f"批量{task_index + 1}",
+
+        # 解析每变体配音（严格守卫：独立配音长度/缺值 → 400，禁静默 fallback）
+        try:
+            variant_voices = resolve_variant_voice_ids(
+                count=count,
+                voice_library_id=request.voice_library_id,
+                voice_library_ids=request.voice_library_ids or None,
+            )
+        except VariantVoiceError as ve:
+            raise HTTPException(status_code=400, detail=str(ve)) from ve
+        # 各变体配音时长（查询硬化：异常 → 0.0 不阻断）
+        voice_durations = _query_voice_durations(db, variant_voices)
+
+        # 解析批量源 plan：优先前端传入；否则按 template_id + user 查最新（与单任务兜底同源）
+        batch_source_plan_id = request.source_edit_plan_id
+        if not batch_source_plan_id and request.template_id:
+            try:
+                from packages.adapters.sqlalchemy_impl.models import EditPlanModel
+
+                _latest = (
+                    db.query(EditPlanModel)
+                    .filter(
+                        EditPlanModel.template_id == request.template_id,
+                        EditPlanModel.created_by_user_id == user_id,
                     )
-                    break
-                except Exception as clone_err:  # noqa: PERF203
-                    last_err = clone_err
-                    logger.warning(
-                        "[生成任务] 克隆变体 plan 失败(尝试%d/2): source=%s error=%s",
-                        _attempt + 1,
-                        request.source_edit_plan_id,
-                        clone_err,
-                        exc_info=True,
-                    )
-            if variant is None:
-                logger.error(
-                    "[生成任务] 克隆变体 plan 重试仍失败，中断批量创建: source=%s",
-                    request.source_edit_plan_id,
-                    exc_info=last_err,
+                    .order_by(EditPlanModel.created_at.desc())
+                    .first()
                 )
+                if _latest:
+                    batch_source_plan_id = _latest.id
+            except Exception:
+                logger.warning("[生成任务] 批量源 plan 解析失败", exc_info=True)
+
+        if not batch_source_plan_id and not request.variant_plan_ids:
+            # 无任何可用源 plan：批量变体无从选片，明确报错，严禁静默共用/同源
+            logger.error("[生成任务] 批量 count=%d 但无可编辑计划（无 source_edit_plan_id/template plan）", count)
+            raise HTTPException(
+                status_code=400,
+                detail="批量生成需要先完成预览生成（缺少剪辑计划）。请先生成预览后再批量创建。",
+            )
+
+        # 批次素材池：请求显式素材 + 库自动匹配素材（resolved_asset_ids）
+        batch_asset_pool = list(dict.fromkeys(resolved_asset_ids or []))
+
+        if request.variant_plan_ids:
+            # ① 前端回传 variant-plans 预生成结果：直接复用（轻量选片接口已建好 plan）
+            if len(request.variant_plan_ids) != count:
                 raise HTTPException(
-                    status_code=500,
-                    detail="创建批量任务失败：无法生成独立剪辑计划，请重试",
-                ) from last_err
-            variant_plan_ids.append(variant.id)
+                    status_code=400,
+                    detail=f"variant_plan_ids 数量({len(request.variant_plan_ids)})与视频数量({count})不一致",
+                )
+            # 校验归属权
+            from packages.adapters.sqlalchemy_impl.models import EditPlanModel
+
+            for _pid in request.variant_plan_ids:
+                _pm = db.query(EditPlanModel).filter(EditPlanModel.id == _pid).first()
+                if _pm is None:
+                    raise HTTPException(status_code=400, detail=f"剪辑计划不存在: {_pid}")
+                if _pm.created_by_user_id and _pm.created_by_user_id != user_id:
+                    raise HTTPException(status_code=403, detail=f"无权使用剪辑计划: {_pid}")
+            variant_plan_ids = list(request.variant_plan_ids)
+        else:
+            # ② 服务端选片：变体 0 clone 源 plan（不污染源 plan）
+            try:
+                _plan0 = _plan_svc.clone_plan_for_variant(
+                    batch_source_plan_id,
+                    created_by_user_id=user_id,
+                    name_suffix="批量1",
+                )
+            except Exception as clone_err:
+                logger.error("[生成任务] 变体0 clone 失败: %s", clone_err, exc_info=True)
+                raise HTTPException(
+                    status_code=500, detail="创建批量任务失败：无法生成独立剪辑计划，请重试"
+                ) from clone_err
+            variant_plan_ids.append(_plan0.id)
+
+            # 变体 1..N-1 独立选片
+            for task_index in range(1, count):
+                variant = None
+                last_err: Exception | None = None
+                for _attempt in range(2):  # 1 次重试，抗 DB 瞬时抖动
+                    try:
+                        variant = _plan_svc.reselect_plan_for_variant(
+                            batch_source_plan_id,
+                            batch_asset_pool,
+                            created_by_user_id=user_id,
+                            name_suffix=f"批量{task_index + 1}",
+                            voice_duration=voice_durations[task_index] if task_index < len(voice_durations) else 0.0,
+                        )
+                        break
+                    except ValueError as ve:
+                        # 素材不足等可预期错误：不重试，直接中断并给出明确提示
+                        logger.warning("[生成任务] 变体独立选片失败(素材不足): %s", ve)
+                        raise HTTPException(
+                            status_code=400,
+                            detail=f"批量生成第 {task_index + 1} 个视频无法独立选片：{ve}。"
+                            "请增加素材库中的视频素材后重试。",
+                        ) from ve
+                    except Exception as reselection_err:  # noqa: PERF203
+                        last_err = reselection_err
+                        logger.warning(
+                            "[生成任务] 变体独立选片失败(尝试%d/2): source=%s error=%s",
+                            _attempt + 1,
+                            batch_source_plan_id,
+                            reselection_err,
+                            exc_info=True,
+                        )
+                if variant is None:
+                    logger.error(
+                        "[生成任务] 变体独立选片重试仍失败，中断批量创建: source=%s",
+                        batch_source_plan_id,
+                        exc_info=last_err,
+                    )
+                    raise HTTPException(
+                        status_code=500,
+                        detail="创建批量任务失败：无法生成独立剪辑计划，请重试",
+                    ) from last_err
+                variant_plan_ids.append(variant.id)
+
+        # ③ 配音时长分配（回传 plan / clone 变体0 均需幂等分配；reselect 已在选片时分配）
+        for _vi, _pid in enumerate(variant_plan_ids):
+            _vd = voice_durations[_vi] if _vi < len(voice_durations) else 0.0
+            if _vd > 0:
+                try:
+                    _plan_svc.apply_voice_duration_to_plan(_pid, _vd)
+                except Exception:
+                    logger.exception("[生成任务] 变体%d 配音时长分配失败（不阻断）: plan=%s", _vi, _pid)
+
+    # N=1 正式生成：渲染侧全局慢放兜底已删除（#1749），enqueue 前也必须按配音分配段长
+    if count == 1 and not request.is_preview:
+        from packages.domain.variant_voice_resolver import VariantVoiceError, resolve_variant_voice_ids
+
+        try:
+            _voices = resolve_variant_voice_ids(
+                count=1,
+                voice_library_id=request.voice_library_id,
+                voice_library_ids=request.voice_library_ids or None,
+            )
+            _single_vd: list[float] = _query_voice_durations(db, _voices)
+            _single_dur = _single_vd[0] if _single_vd else 0.0
+            _single_plan = request.source_edit_plan_id
+            if not _single_plan and request.template_id:
+                try:
+                    from packages.adapters.sqlalchemy_impl.models import EditPlanModel
+
+                    _latest = (
+                        db.query(EditPlanModel)
+                        .filter(
+                            EditPlanModel.template_id == request.template_id,
+                            EditPlanModel.created_by_user_id == user_id,
+                        )
+                        .order_by(EditPlanModel.created_at.desc())
+                        .first()
+                    )
+                    if _latest:
+                        _single_plan = _latest.id
+                except Exception:
+                    logger.warning("[生成任务] 单任务源 plan 解析失败", exc_info=True)
+            if _single_dur > 0 and _single_plan:
+                from app.services.edit_plan_service import EditPlanService
+
+                try:
+                    EditPlanService(db).apply_voice_duration_to_plan(_single_plan, _single_dur)
+                except Exception:
+                    logger.exception("[生成任务] N=1 配音时长分配失败（不阻断）: plan=%s", _single_plan)
+        except VariantVoiceError as ve:
+            raise HTTPException(status_code=400, detail=str(ve)) from ve
+        except Exception:
+            logger.exception("[生成任务] N=1 配音分配兜底异常（不阻断）")
 
     try:
         for task_index in range(count):
-            # 第 1 条复用源 plan（保留用户编辑结果）；其余使用预克隆的独立变体 plan。
-            # 无源 plan（source_edit_plan_id 为空）时无可克隆对象，variant_plan_ids
-            # 为空列表：各任务走自身随机选片流程，不做索引访问（防 IndexError）
-            effective_plan_id = request.source_edit_plan_id
-            if task_index > 0 and variant_plan_ids:
-                effective_plan_id = variant_plan_ids[task_index - 1]
+            # #1749：count>1 时每个变体（含变体0）都关联各自独立 plan（clone/reselect/variant-plans）。
+            if count > 1 and variant_plan_ids:
+                effective_plan_id = variant_plan_ids[task_index]
+            else:
+                effective_plan_id = request.source_edit_plan_id
 
             # 变体级独立配置：titles[]/voice_library_ids[]/cover_urls[]
             # 长度1=所有变体共用，长度=count=每个变体独立，空数组=回退单值字段
@@ -500,7 +672,6 @@ def create_generation_task(
                     template_id=request.template_id,
                     asset_ids=resolved_asset_ids,
                     title_ids=request.title_ids,
-                    voice_ids=request.voice_ids,
                     created_by_user_id=user_id,
                     source_edit_plan_id=effective_plan_id,
                     asset_select_mode=request.asset_select_mode,
@@ -523,7 +694,19 @@ def create_generation_task(
             try:
                 # 兜底关联编辑计划：前端未传 source_edit_plan_id 时，
                 # 通过 template_id + user_id 在 DB 层直接查找最新的 plan。
-                # 必须在 enqueue 之前执行，避免 worker 读取时 source_edit_plan_id 为空（竞态条件）
+                # 必须在 enqueue 之前执行，避免 worker 读取时 source_edit_plan_id 为空（竞态条件）。
+                # #1743：批量（count>1）场景严禁兜底共用——变体 plan 已在上方预生成，
+                # 走到这里还缺 plan 说明预生成漏配，直接报错中断，不允许 N 任务关联同一 plan。
+                if not task.source_edit_plan_id and count > 1:
+                    logger.error(
+                        "[生成任务] 批量任务缺少独立 plan（禁止共用兜底）: task_index=%d task_id=%s",
+                        task_index,
+                        task.id,
+                    )
+                    raise HTTPException(
+                        status_code=500,
+                        detail="创建批量任务失败：变体剪辑计划缺失，请重新预览后再批量生成。",
+                    )
                 if not task.source_edit_plan_id and request.template_id:
                     try:
                         from packages.adapters.sqlalchemy_impl.models import EditPlanModel
@@ -690,7 +873,6 @@ def confirm_generation(
             template_id=source_task.template_id,
             asset_ids=source_task.asset_ids,
             title_ids=source_task.title_ids,
-            voice_ids=source_task.voice_ids,
             created_by_user_id=authenticated_user.user.id,
             source_edit_plan_id=source_task.source_edit_plan_id or "",
             asset_select_mode=source_task.asset_select_mode,
@@ -834,7 +1016,6 @@ def retry_generation_task(
             template_id=task.template_id,
             asset_ids=task.asset_ids,
             title_ids=task.title_ids,
-            voice_ids=task.voice_ids,
             created_by_user_id=user_id,
             source_edit_plan_id=task.source_edit_plan_id or "",
             asset_select_mode=getattr(task, "asset_select_mode", ""),

apps/api/app/api/routes/generation_variant_plans.py

@@ -0,0 +1,178 @@
+"""轻量选片接口 POST /generation/variant-plans（#1749）。
+
+与正式生成共用同一套选片函数（EditPlanService.ensure_variant_plans →
+clone_plan_for_variant / reselect_plan_for_variant → variant_plan_selector），
+但**不建任务、不入队、不渲染**：
+
+- 仅为 N 个变体创建/选好 EditPlan + clips，返回 plan_id 与片段列表；
+- 前端确认后调正式生成接口回传 variant_plan_ids，直接复用这些 plan，
+  不再重复选片（回传后仍按各变体配音幂等重分配段长）；
+- 配音守卫：voice_library_ids 长度/缺值 → 400（variant_voice_resolver），
+  禁静默 fallback；
+- 素材不足等选片失败 → 400（与正式生成同口径）；除此之外不报错打断。
+"""
+
+from __future__ import annotations
+
+import logging
+from typing import Any
+
+from app.auth import AuthenticatedUser, get_current_user
+from app.dependencies import get_db_session
+from fastapi import APIRouter, Depends, HTTPException
+from pydantic import BaseModel, Field, model_validator
+from sqlalchemy.orm import Session
+
+from packages.domain.variant_voice_resolver import VariantVoiceError, resolve_variant_voice_ids
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter()
+
+
+class VariantPlanRequest(BaseModel):
+    """轻量选片请求体（与前端 variantPlans.ts 契约一致）。"""
+
+    template_id: str = Field(default="", description="模板 ID（无 source_edit_plan_id 时用于查找骨架 plan）")
+    asset_ids: list[str] = Field(default_factory=list, description="批次素材池")
+    count: int = Field(default=1, ge=1, le=50, description="变体数量")
+    source_edit_plan_id: str = Field(default="", description="源剪辑计划 ID（优先）")
+    # 配音（可选；传独立配音时严格守卫）
+    voice_library_id: str = Field(default="", description="统一配音 ID")
+    voice_library_ids: list[str] = Field(default_factory=list, description="独立配音 ID 列表（长度须=count）")
+
+    @model_validator(mode="after")
+    def _validate(self) -> "VariantPlanRequest":
+        if not self.template_id.strip() and not self.source_edit_plan_id.strip():
+            raise ValueError("template_id 与 source_edit_plan_id 至少需要提供一个")
+        try:
+            resolve_variant_voice_ids(
+                count=self.count,
+                voice_library_id=self.voice_library_id,
+                voice_library_ids=self.voice_library_ids or None,
+            )
+        except VariantVoiceError as exc:
+            raise ValueError(str(exc)) from exc
+        return self
+
+
+class VariantPlanItem(BaseModel):
+    variant_index: int
+    plan_id: str
+    clips: list[dict[str, Any]] = Field(default_factory=list)
+
+
+class VariantPlanResponse(BaseModel):
+    items: list[VariantPlanItem]
+    total: int
+
+
+@router.post("/variant-plans", response_model=VariantPlanResponse)
+def create_variant_plans(
+    request: VariantPlanRequest,
+    authenticated_user: AuthenticatedUser = Depends(get_current_user),
+    db: Session = Depends(get_db_session),
+) -> VariantPlanResponse:
+    """轻量选片：为 N 个变体创建独立 EditPlan + clips，不建任务/不渲染。
+
+    Returns:
+        200 + {items: [{variant_index, plan_id, clips}], total}
+    """
+    user_id = authenticated_user.user.id
+
+    # 配音严格守卫（schema 已校验，此处复用解析取每变体配音）
+    try:
+        voices = resolve_variant_voice_ids(
+            count=request.count,
+            voice_library_id=request.voice_library_id,
+            voice_library_ids=request.voice_library_ids or None,
+        )
+    except VariantVoiceError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc
+
+    # 解析源 plan：显式传入优先；否则按 template_id + user 查最新
+    source_plan_id = request.source_edit_plan_id.strip()
+    if not source_plan_id and request.template_id.strip():
+        try:
+            from packages.adapters.sqlalchemy_impl.models import EditPlanModel
+
+            _latest = (
+                db.query(EditPlanModel)
+                .filter(
+                    EditPlanModel.template_id == request.template_id.strip(),
+                    EditPlanModel.created_by_user_id == user_id,
+                )
+                .order_by(EditPlanModel.created_at.desc())
+                .first()
+            )
+            if _latest:
+                source_plan_id = _latest.id
+        except Exception:
+            logger.warning("[variant-plans] 源 plan 解析失败", exc_info=True)
+
+    if not source_plan_id:
+        raise HTTPException(
+            status_code=400,
+            detail="缺少剪辑计划：请先完成一次预览生成（或传入 source_edit_plan_id）后再试。",
+        )
+
+    # 配音时长（硬化：异常 → 0.0 不阻断选片）
+    try:
+        from app.api.routes.generation_tasks import _query_voice_durations
+
+        voice_durations = _query_voice_durations(db, voices)
+    except Exception:
+        logger.warning("[variant-plans] 配音时长查询失败（按占位段长选片）", exc_info=True)
+        voice_durations = [0.0] * request.count
+
+    from app.services.edit_plan_service import EditPlanService
+
+    svc = EditPlanService(db)
+    try:
+        plan_ids = svc.ensure_variant_plans(
+            source_plan_id,
+            request.count,
+            list(dict.fromkeys(request.asset_ids or [])),
+            created_by_user_id=user_id,
+            voice_durations=voice_durations,
+        )
+    except ValueError as ve:
+        # 素材池为空/时长全未知等可预期错误 → 400（与正式生成同口径）
+        logger.warning("[variant-plans] 选片失败: %s", ve)
+        raise HTTPException(status_code=400, detail=f"变体选片失败：{ve}。请增加素材后重试。") from ve
+    except HTTPException:
+        raise
+    except Exception as e:
+        logger.error("[variant-plans] 选片异常: %s", e, exc_info=True)
+        raise HTTPException(status_code=500, detail="选片失败，请稍后重试") from e
+
+    # 组装 clips 响应
+    items: list[VariantPlanItem] = []
+    for idx, pid in enumerate(plan_ids):
+        clips = svc.list_clips(pid)
+        clip_dicts = [
+            {
+                "id": c.id,
+                "order": c.order,
+                "asset_id": c.asset_id,
+                "start_time": float(c.start_time or 0.0),
+                "duration": float(c.duration or 0.0),
+                "clip_type": c.clip_type,
+                "transition_effect": c.transition_effect,
+                "transition_duration": float(c.transition_duration or 0.0),
+                "playback_speed": float(c.playback_speed or 1.0),
+                "text_content": c.text_content or "",
+                "status": c.status or "ready",
+            }
+            for c in clips
+        ]
+        items.append(VariantPlanItem(variant_index=idx, plan_id=pid, clips=clip_dicts))
+
+    logger.info(
+        "[variant-plans] 轻量选片完成: user=%s source=%s count=%d plans=%d",
+        user_id,
+        source_plan_id,
+        request.count,
+        len(plan_ids),
+    )
+    return VariantPlanResponse(items=items, total=len(items))

apps/api/app/api/routes/templates_editor/clips.py

@@ -460,6 +460,11 @@ def _get_template_segments(
     except Exception:
         logger.warning("旧模板系统查询segments失败", exc_info=True)
 
+    # 所有途径都失败：模板没有片段配置（可能是无效测试模板）
+    logger.error(
+        "模板无片段配置：template_id=%s（可能是 is_active=false 的无效模板）",
+        template_id,
+    )
     return []
 
 

apps/api/app/schemas/generation_task.py

@@ -36,9 +36,13 @@ class CreateGenerationTaskRequest(BaseModel):
     template_id: str = ""
     asset_ids: list[str] = Field(default_factory=list)
     title_ids: list[str] = Field(default_factory=list)
-    voice_ids: list[str] = Field(default_factory=list)
     # ── 来源剪辑计划 ──
     source_edit_plan_id: str = ""
+    # ── variant-plans 轻量选片回传（#1749）：正式生成直接复用，不再重选 ──
+    variant_plan_ids: list[str] = Field(
+        default_factory=list,
+        description="POST /generation/variant-plans 返回的各变体 plan_id（长度须=count）；为空则走服务端选片",
+    )
     # ── 标题配置（结构化）──
     title_config: dict | None = Field(
         default=None,
@@ -96,11 +100,31 @@ class CreateGenerationTaskRequest(BaseModel):
 
     @model_validator(mode="after")
     def _check_variant_arrays(self) -> "CreateGenerationTaskRequest":
-        """变体数组字段长度校验：空数组（回退单值）、长度 1（共用）、或长度 = count（独立）。"""
-        for name in ("voice_library_ids", "cover_urls", "titles"):
+        """变体数组字段长度校验 + #1749 配音严格守卫。
+
+        - cover_urls/titles：空（回退单值）、长度 1（共用）或长度 = count（独立）；
+        - voice_library_ids：独立配音长度必须恰好 = count 且逐项非空，禁止静默 fallback
+          （长度 1 的"共用"场景请用 voice_library_id 单值字段）；
+        - variant_plan_ids：非空时长度必须 = count。
+        """
+        for name in ("cover_urls", "titles"):
             arr = getattr(self, name)
             if arr and len(arr) != 1 and len(arr) != self.count:
                 raise ValueError(f"{name} 长度必须为 1（共用）或 {self.count}（与 count 一致），当前为 {len(arr)}")
+
+        from packages.domain.variant_voice_resolver import VariantVoiceError, resolve_variant_voice_ids
+
+        try:
+            resolve_variant_voice_ids(
+                count=self.count,
+                voice_library_id=self.voice_library_id,
+                voice_library_ids=self.voice_library_ids or None,
+            )
+        except VariantVoiceError as exc:
+            raise ValueError(str(exc)) from exc
+
+        if self.variant_plan_ids and len(self.variant_plan_ids) != self.count:
+            raise ValueError(f"variant_plan_ids 长度({len(self.variant_plan_ids)})必须与 count({self.count})一致")
         return self
 
     @model_validator(mode="after")
@@ -110,9 +134,9 @@ class CreateGenerationTaskRequest(BaseModel):
         if not has_project and not has_template:
             raise ValueError("project_id 或 template_id 至少需要提供一个")
         has_library = bool(self.asset_library_id.strip())
-        has_assets = bool(self.asset_ids or self.title_ids or self.voice_ids)
+        has_assets = bool(self.asset_ids or self.title_ids)
         if not has_library and not has_assets:
-            raise ValueError("asset_library_id 或 asset_ids/title_ids/voice_ids 至少需要提供一个")
+            raise ValueError("asset_library_id 或 asset_ids/title_ids 至少需要提供一个")
         return self
 
 
@@ -189,7 +213,6 @@ class CreatePreviewGenerationTaskRequest(BaseModel):
     template_id: str
     asset_ids: list[str] = Field(default_factory=list)
     title_ids: list[str] = Field(default_factory=list)
-    voice_ids: list[str] = Field(default_factory=list)
     voice_library_id: str = Field(
         default="", description="配音素材库ID（用户上传的音频或AI配音），对应配音选择页面选择的配音素材"
     )
@@ -231,13 +254,24 @@ class CreatePreviewGenerationTaskRequest(BaseModel):
 
     @model_validator(mode="after")
     def _check_variant_arrays(self) -> "CreatePreviewGenerationTaskRequest":
-        """变体数组字段长度校验：空数组（回退单值）、长度 1（共用）、或长度 = preview_count（独立）。"""
-        for name in ("titles", "voice_library_ids", "cover_urls"):
+        """变体数组字段长度校验 + #1749 配音严格守卫。"""
+        for name in ("titles", "cover_urls"):
             arr = getattr(self, name)
             if arr and len(arr) != 1 and len(arr) != self.preview_count:
                 raise ValueError(
                     f"{name} 长度必须为 1（共用）或 {self.preview_count}（与 preview_count 一致），当前为 {len(arr)}"
                 )
+
+        from packages.domain.variant_voice_resolver import VariantVoiceError, resolve_variant_voice_ids
+
+        try:
+            resolve_variant_voice_ids(
+                count=self.preview_count,
+                voice_library_id=self.voice_library_id,
+                voice_library_ids=self.voice_library_ids or None,
+            )
+        except VariantVoiceError as exc:
+            raise ValueError(str(exc)) from exc
         return self
 
     @model_validator(mode="after")
@@ -248,8 +282,8 @@ class CreatePreviewGenerationTaskRequest(BaseModel):
 
     @model_validator(mode="after")
     def _check_asset_ids(self) -> "CreatePreviewGenerationTaskRequest":
-        if not self.asset_ids and not self.title_ids and not self.voice_ids:
-            raise ValueError("asset_ids/title_ids/voice_ids 至少需要提供一个")
+        if not self.asset_ids and not self.title_ids:
+            raise ValueError("asset_ids/title_ids 至少需要提供一个")
         return self
 
 

apps/api/app/services/edit_plan_service.py

@@ -409,8 +409,13 @@ class EditPlanService:
                     clip_type=clip_item.get("clip_type", "main"),
                     order=order,
                     asset_id=clip_item.get("asset_id", ""),
+                    text_content=clip_item.get("text_content", ""),
                     start_time=clip_item.get("start_time", 0.0),
                     duration=clip_item.get("duration", 0.0),
+                    transition_effect=clip_item.get("transition_effect", "cut"),
+                    transition_duration=clip_item.get("transition_duration", 0.0),
+                    playback_speed=clip_item.get("playback_speed", 1.0),
+                    config=clip_item.get("config") or None,
                 )
                 model = EditPlanClipModel(
                     id=clip.id,
@@ -459,6 +464,159 @@ class EditPlanService:
             logger.exception("事务性替换片段失败: plan_id=%s", plan_id)
             raise
 
+    def reselect_plan_for_variant(
+        self,
+        source_plan_id: str,
+        candidate_asset_ids: list[str],
+        *,
+        created_by_user_id: str = "",
+        name_suffix: str = "变体",
+        voice_duration: float = 0.0,
+        rng=None,
+    ) -> EditPlan:
+        """为批量变体生成独立 plan：完整重跑单视频选片流程（#1743）。
+
+        与 clone_plan_for_variant（只重算起点、素材/顺序不变）不同，本方法：
+        - 源 plan 片段骨架（clip_type/order/duration/文案/转场）保留；
+        - 素材池 shuffle 随机分配 + main 片段顺序洗牌；
+        - 起点走场景镜头洗牌/随机起点/历史区间避让（与单视频同一入口）；
+        - 批次内同素材区间重叠 >20% 自动重选起点；
+        - 新片段区间 record_used_segments 写回素材 metadata（跨变体/跨任务避让）。
+
+        Args:
+            source_plan_id: 源 plan（任务 0 / 预览源）。
+            candidate_asset_ids: 素材池（源 plan 素材 ∪ 批次素材）。
+            created_by_user_id: 新 plan 归属用户。
+            name_suffix: plan 名后缀。
+            rng: 可选随机数（测试注入种子）。
+
+        Raises:
+            ValueError: 源 plan 不存在/无片段、素材池为空或时长全未知。
+        """
+        from packages.adapters.sqlalchemy_impl.models import AssetModel
+        from packages.domain.plan_generator_utils import extract_scene_points_from_metadata
+        from packages.domain.variant_plan_selector import reselect_clips_for_variant
+
+        source = self.get_plan_or_raise(source_plan_id)
+
+        # 分页读取源 plan 全部片段
+        clips: List[EditPlanClip] = []
+        skip, page = 0, 500
+        while True:
+            batch = self._clip_repo.list_by_plan(source_plan_id, skip=skip, limit=page)
+            if not batch:
+                break
+            clips.extend(batch)
+            if len(batch) < page:
+                break
+            skip += page
+        if not clips:
+            raise ValueError(f"源 plan 无片段，无法生成变体: {source_plan_id}")
+
+        source_clips_data: list[dict[str, Any]] = [
+            {
+                "order": c.order if c.order is not None else i,
+                "asset_id": c.asset_id,
+                "start_time": float(c.start_time or 0.0),
+                "duration": float(c.duration or 0.0),
+                "clip_type": c.clip_type,
+                "playback_speed": float(c.playback_speed or 1.0),
+                "transition_effect": c.transition_effect,
+                "transition_duration": float(c.transition_duration or 0.0),
+                "text_content": c.text_content or "",
+                "config": c.config or {},
+            }
+            for i, c in enumerate(clips)
+        ]
+
+        db = self._clip_repo.session
+
+        # #1749：配音时长 → 每段目标段长（片段数=模板片段数定死；素材不足由渲染末帧冻结铺满）
+        target_durations: list[float] | None = None
+        try:
+            voice = float(voice_duration or 0.0)
+        except (TypeError, ValueError):
+            voice = 0.0
+        if voice > 0 and source_clips_data:
+            from packages.domain.voice_duration_planner import plan_clip_durations
+
+            _effects: list[str | None] = [c.get("transition_effect") for c in source_clips_data]
+            _tdurs: list[float] = [float(c.get("transition_duration") or 0.0) for c in source_clips_data]
+            target_durations = plan_clip_durations(
+                len(source_clips_data),
+                voice,
+                transition_effects=_effects,
+                transition_durations=_tdurs,
+            )
+            if target_durations:
+                for _c, _d in zip(source_clips_data, target_durations, strict=False):
+                    _c["duration"] = _d
+
+        # 素材池 = 源 plan 素材 ∪ 调用方传入素材（去重保序）
+        pool_ids: list[str] = []
+        seen = set()
+        for aid in [c.asset_id for c in clips if c.asset_id] + list(candidate_asset_ids or []):
+            if aid and aid not in seen:
+                seen.add(aid)
+                pool_ids.append(aid)
+
+        # 时长 + 场景点
+        durations: dict[str, float] = {}
+        scene_points: dict[str, list[float]] = {}
+        if pool_ids:
+            for m in db.query(AssetModel).filter(AssetModel.id.in_(pool_ids)).all():
+                durations[m.id] = float(getattr(m, "duration", 0.0) or 0.0)
+                pts = extract_scene_points_from_metadata(getattr(m, "metadata", None))
+                if pts:
+                    scene_points[m.id] = pts
+
+        historical = get_used_segments(db, pool_ids)
+
+        # 创建新 plan（复制模板归属与 config）
+        new_plan = self.create_plan(
+            template_id=source.template_id,
+            name=f"{source.name or '剪辑计划'} · {name_suffix}",
+            config=dict(source.config or {}),
+            total_duration=source.total_duration,
+            project_id=source.project_id or "",
+            created_by_user_id=created_by_user_id or (source.created_by_user_id or ""),
+        )
+
+        # 批次内区间：以源 plan（变体 0）片段为初始避让对象
+        batch_segments: dict[str, list[tuple[float, float]]] = {}
+        for c in clips:
+            if c.asset_id and float(c.duration or 0) > 0:
+                st = float(c.start_time or 0.0)
+                batch_segments.setdefault(c.asset_id, []).append((st, st + float(c.duration)))
+
+        clips_data = reselect_clips_for_variant(
+            source_clips_data,
+            pool_ids,
+            asset_durations=durations,
+            asset_scene_points=scene_points,
+            historical_used_segments=historical,
+            batch_segments=batch_segments,
+            target_durations=target_durations,
+            rng=rng,
+        )
+
+        # 片段区间写回素材 metadata（与落库同事务；replace_all_clips_transactional 内 commit）
+        for item in clips_data:
+            aid = item.get("asset_id", "")
+            if aid:
+                st = float(item.get("start_time", 0.0))
+                record_used_segments(db, aid, st, st + float(item.get("duration", 0.0)), new_plan.id)
+
+        self.replace_all_clips_transactional(new_plan.id, clips_data)
+        logger.info(
+            "变体独立选片完成: source=%s new=%s clips=%d assets=%d",
+            source_plan_id,
+            new_plan.id,
+            len(clips_data),
+            len(pool_ids),
+        )
+        return new_plan
+
     def clone_plan_for_variant(
         self,
         source_plan_id: str,
@@ -569,6 +727,243 @@ class EditPlanService:
         )
         return new_plan
 
+    # ── #1749 配音时长分配 / 素材时长查询 / 批量变体 plan 确保 ──────────────
+
+    def get_asset_durations(self, asset_ids: list[str]) -> dict[str, float]:
+        """批量查询素材时长（秒），O(N) 单查；缺失/异常返回 0.0。"""
+        from packages.adapters.sqlalchemy_impl.models import AssetModel
+
+        ids = [a for a in dict.fromkeys(asset_ids or []) if a]
+        if not ids:
+            return {}
+        db = self._clip_repo.session
+        out: dict[str, float] = {}
+        for m in db.query(AssetModel).filter(AssetModel.id.in_(ids)).all():
+            try:
+                out[m.id] = float(getattr(m, "duration", 0.0) or 0.0)
+            except (TypeError, ValueError):
+                out[m.id] = 0.0
+        return out
+
+    def apply_voice_duration_to_plan(self, plan_id: str, voice_duration: float) -> Optional[EditPlan]:
+        """把配音时长分配到 plan 的每段（#1749）。
+
+        - 片段数保持不变（= 模板片段数，定死）；
+        - 每段 duration 按 voice_duration_planner 分配（含转场重叠扣减）；
+        - 素材短于段长 → start_time 钳制为 0（末帧冻结由渲染侧 tpad/apad 铺满）；
+        - plan.total_duration 回写为成片净时长（≈ 配音时长）；
+        - 幂等：配音时长相同则分配结果不变，可重复调用。
+
+        无配音（<=0）或无片段时直接返回 None，不报错。
+        """
+        try:
+            voice = float(voice_duration or 0.0)
+        except (TypeError, ValueError):
+            return None
+        if voice <= 0:
+            return None
+
+        plan = self.get_plan(plan_id)
+        if plan is None:
+            return None
+
+        clips: List[EditPlanClip] = []
+        skip, page = 0, 500
+        while True:
+            batch = self._clip_repo.list_by_plan(plan_id, skip=skip, limit=page)
+            if not batch:
+                break
+            clips.extend(batch)
+            if len(batch) < page:
+                break
+            skip += page
+        if not clips:
+            return None
+
+        clips.sort(key=lambda c: (c.order if c.order is not None else 0))
+
+        from packages.domain.voice_duration_planner import plan_clip_durations, total_output_duration
+
+        # #1764：从 plan config 读取节奏模板
+        rhythm_template = None
+        if plan and hasattr(plan, "config") and plan.config:
+            rhythm_template = plan.config.get("rhythm_template")
+
+        target = plan_clip_durations(
+            len(clips),
+            voice,
+            transition_effects=[c.transition_effect for c in clips],
+            transition_durations=[float(c.transition_duration or 0.0) for c in clips],
+            rhythm_template=rhythm_template,
+        )
+        if not target:
+            return None
+
+        # 素材时长（短素材起点钳 0）
+        asset_ids = [c.asset_id for c in clips if c.asset_id]
+        durations = self.get_asset_durations(asset_ids)
+
+        clips_data: list[dict] = []
+        for i, c in enumerate(clips):
+            dur = float(target[i])
+            total = durations.get(c.asset_id, 0.0)
+            start = float(c.start_time or 0.0)
+            if c.asset_id and total > 0:
+                # 素材短于段长：起点钳 0，段长超出部分渲染侧末帧冻结
+                max_start = max(0.0, total - min(dur, total))
+                start = min(start, max_start)
+            clips_data.append(
+                {
+                    "order": c.order if c.order is not None else i,
+                    "asset_id": c.asset_id or "",
+                    "start_time": round(start, 3),
+                    "duration": dur,
+                    "clip_type": c.clip_type,
+                    "playback_speed": float(c.playback_speed or 1.0),
+                    "transition_effect": c.transition_effect,
+                    "transition_duration": float(c.transition_duration or 0.0),
+                    "text_content": c.text_content or "",
+                    "config": c.config or {},
+                }
+            )
+
+        self.replace_all_clips_transactional(plan_id, clips_data)
+
+        net = total_output_duration(
+            target,
+            transition_effects=[c.transition_effect for c in clips],
+            transition_durations=[float(c.transition_duration or 0.0) for c in clips],
+        )
+        try:
+            plan.total_duration = net
+            db = self._clip_repo.session
+            db.commit()
+        except Exception:
+            db.rollback()
+            logger.exception("回写 plan.total_duration 失败（不阻断）: plan_id=%s", plan_id)
+
+        logger.info(
+            "配音时长分配完成: plan=%s clips=%d voice=%.2fs 成片净时长=%.2fs",
+            plan_id,
+            len(clips),
+            voice,
+            net,
+        )
+        return plan
+
+    def ensure_variant_plans(
+        self,
+        source_plan_id: str,
+        count: int,
+        candidate_asset_ids: list[str],
+        *,
+        created_by_user_id: str = "",
+        voice_durations: Optional[list[float]] = None,
+        rng=None,
+    ) -> list[str]:
+        """确保批量 N 个变体各自拥有独立 plan（#1749 批量正式生成/预览共用）。
+
+        - 变体 0：clone 源 plan（不污染源 plan，片段独立可改），并按配音分配段长；
+        - 变体 1..N-1：reselect_plan_for_variant 完整重跑选片（素材级去重）；
+        - voice_durations：每个变体的配音时长（独立配音各自时长；统一配音同值）；
+          缺省/为 0 时不分配（段长保持骨架/模板值）。
+
+        Returns:
+            plan_id 列表，长度 == count，index 即 variant_index。
+        """
+        import random as _random
+
+        rng = rng or _random.Random()
+        plan_ids: list[str] = []
+
+        # 变体 0：clone（片段结构同源 plan，起点重算），不污染源 plan
+        plan0 = self.clone_plan_for_variant(
+            source_plan_id,
+            created_by_user_id=created_by_user_id,
+            name_suffix="变体1",
+        )
+        v0_voice = 0.0
+        if voice_durations and len(voice_durations) > 0:
+            try:
+                v0_voice = float(voice_durations[0] or 0.0)
+            except (TypeError, ValueError):
+                v0_voice = 0.0
+        if v0_voice > 0:
+            try:
+                self.apply_voice_duration_to_plan(plan0.id, v0_voice)
+            except Exception:
+                logger.exception("变体0 配音分配失败（不阻断）: plan=%s", plan0.id)
+        plan_ids.append(plan0.id)
+
+        # 变体 1..N-1：独立选片
+        for i in range(1, count):
+            voice = 0.0
+            if voice_durations and i < len(voice_durations):
+                try:
+                    voice = float(voice_durations[i] or 0.0)
+                except (TypeError, ValueError):
+                    voice = 0.0
+            variant = self.reselect_plan_for_variant(
+                source_plan_id,
+                candidate_asset_ids,
+                created_by_user_id=created_by_user_id,
+                name_suffix=f"变体{i + 1}",
+                voice_duration=voice,
+                rng=rng,
+            )
+            plan_ids.append(variant.id)
+
+        # #1764：为每个变体生成独立节奏模板（让批量视频片段时长分布不同）
+        from packages.domain.voice_duration_planner import RHYTHM_TEMPLATES, adapt_template_length
+
+        clip_count = 0
+        if voice_durations and len(voice_durations) > 0:
+            # 从源 plan 获取片段数
+            source_plan = self.get_plan(source_plan_id)
+            if source_plan and hasattr(source_plan, "clips"):
+                clip_count = len(list(source_plan.clips)) if source_plan.clips else 0
+
+        rhythm_templates_for_variants = []
+        if clip_count > 0:
+            for idx in range(len(plan_ids)):
+                # 每个变体用不同的 seed 选择节奏模板
+                variant_seed = rng.randint(0, 999999)
+                template = adapt_template_length(RHYTHM_TEMPLATES[variant_seed % len(RHYTHM_TEMPLATES)], clip_count)
+                rhythm_templates_for_variants.append(template)
+                logger.info("变体 %d 节奏模板: plan=%s template=%s", idx, plan_ids[idx], template)
+
+        # 为每个变体生成独立视觉扰动参数（让批量视频画面本身更不同）
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        for idx, pid in enumerate(plan_ids):
+            try:
+                perturbation = generate_visual_perturbation(rng)
+                # 变体 0 不做 hflip（保持预览 plan 原始画面方向）
+                if idx == 0:
+                    perturbation["hflip"] = False
+                config_update = {"visual_perturbation": perturbation}
+                # #1764：写入节奏模板
+                if idx < len(rhythm_templates_for_variants):
+                    config_update["rhythm_template"] = rhythm_templates_for_variants[idx]
+                # #1765：写入像素级扰动滤镜
+                from packages.domain.variant_plan_selector import generate_pixel_perturbation
+
+                pixel_pert = generate_pixel_perturbation(rng)
+                config_update["pixel_perturbation"] = pixel_pert
+                self.update_plan_config(pid, config_update)
+                logger.info("变体 %d 视觉扰动+像素扰动: plan=%s vis=%s pix=%s", idx, pid, perturbation, pixel_pert)
+            except Exception:
+                logger.exception("变体 %d 视觉扰动生成失败（不阻断）: plan=%s", idx, pid)
+
+        # 标记所有变体 plan 的 clips 为 ready（已分配素材+起点，语义上就是 ready）
+        for pid in plan_ids:
+            try:
+                self.mark_clips_ready(pid)
+            except Exception:
+                logger.exception("标记 clips ready 失败（不阻断）: plan=%s", pid)
+
+        return plan_ids
+
     # ── 片段分割与合并 ──────────────────────────────────────────────────────
 
     def split_clip(self, clip_id: str, split_time: float) -> Dict[str, Any]:

apps/web/src/api/editing-planner/types.ts

@@ -44,8 +44,10 @@ export interface BgmConfig {
 export interface TemplateSegment {
   id?: string
   segment_order: number
-  duration_min: number
-  duration_max: number
+  /** @deprecated 模板无时长概念（#1750 基线）：字段保留仅为兼容旧数据读取，新模板可不传 */
+  duration_min?: number
+  /** @deprecated 同上 */
+  duration_max?: number
   material_type: string | null
 }
 
@@ -59,7 +61,8 @@ export interface EditingTemplate {
   title_config: TitleConfig
   subtitle_config: SubtitleConfig
   bgm_config: BgmConfig
-  estimated_duration: number
+  /** @deprecated 模板无时长概念（#1750 基线）：成片时长由配音时长决定；字段保留兼容旧数据 */
+  estimated_duration?: number
   segments: TemplateSegment[]
   watermark_config?: WatermarkConfig
   intro_outro_config?: IntroOutroConfig
@@ -89,7 +92,8 @@ export interface SaveTemplatePayload {
   title_config: TitleConfig
   subtitle_config: SubtitleConfig
   bgm_config: BgmConfig
-  estimated_duration: number
+  /** @deprecated 模板无时长概念（#1750 基线）：保留兼容旧数据 */
+  estimated_duration?: number
   segments: Omit<TemplateSegment, "id">[]
   watermark_config?: WatermarkConfig
   intro_outro_config?: IntroOutroConfig

apps/web/src/api/generation/variantPlans.ts

@@ -0,0 +1,61 @@
+/**
+ * 批量变体剪辑计划 API（#1744）
+ *
+ * 批量预览时向后端申请 N 个变体的「独立剪辑计划片段」：
+ * - 变体 0 保留源 plan（用户在编辑器/智能选片产出的片段，含标题样式编辑结果）；
+ * - 变体 1..N-1 由后端 reselect_plan_for_variant 完整重跑单视频选片流程
+ *   （素材洗牌 + main 片段顺序洗牌 + 镜头/起点随机 + 跨变体 20% 区间避让 +
+ *   素材使用区间写回 metadata），与正式批量生成 POST /generation/tasks?count=N
+ *   使用同一套选片逻辑；
+ * - 正式生成时把 variant_plan_ids 原样回传，后端直接关联这些 plan 渲染，
+ *   不再重新选片 —— 预览所见即成片。
+ *
+ * 该接口只做选片/建 plan（秒级），不触发视频渲染，无渲染成本。
+ * 后端端点未上线（404）或选片失败（素材不足等）时前端降级为本地 variantSeed
+ * 模拟预览，不阻塞用户流程。
+ */
+import apiClient from "../client"
+import type { EditPlanClip } from "../template-editor"
+
+/** 批量变体计划请求体 */
+export interface BatchVariantPlansRequest {
+  template_id: string
+  /** 本批次素材池（手动选择或智能匹配结果） */
+  asset_ids: string[]
+  /** 变体数量（≥1）；=1 时只返回源 plan 片段 */
+  count: number
+  /** 源剪辑计划 ID：优先取预览/草稿关联的 plan；不传由后端按 template_id+user 兜底最新 plan */
+  source_edit_plan_id?: string
+}
+
+/** 单个变体的计划片段 */
+export interface VariantPlan {
+  /** 变体序号，从 0 开始 */
+  variant_index: number
+  /** 该变体关联的剪辑计划 ID（正式生成时回传，实现预览即成片） */
+  plan_id: string
+  /** 该变体的真实片段（顺序/素材/起点与正式成片一致） */
+  clips: EditPlanClip[]
+}
+
+/** 批量变体计划响应 */
+export interface BatchVariantPlansResponse {
+  items: VariantPlan[]
+  total: number
+}
+
+/**
+ * 创建批量变体剪辑计划并返回各变体片段。
+ *
+ * 注意：端点 404（后端未上线）/ 400（素材不足）等失败由调用方 catch 后降级，
+ * 不要抛 unhandled rejection。
+ */
+export async function createBatchVariantPlans(
+  params: BatchVariantPlansRequest,
+): Promise<BatchVariantPlansResponse> {
+  const response = await apiClient.post<BatchVariantPlansResponse>(
+    "/generation/variant-plans",
+    params,
+  )
+  return response.data
+}

apps/web/src/api/tasks/types.ts

@@ -100,6 +100,12 @@ export interface CreateGenerationTaskRequest {
   voice_library_ids?: string[]
   /** 各变体独立封面URL：长度1=共用，长度=count=独立，空数组=回退 cover_url */
   cover_urls?: string[]
+  /**
+   * 批量变体剪辑计划 ID（#1744）：预览阶段后端独立选片产出的 plan id 列表
+   * （按变体全量索引，长度=previewCount）。正式生成回传后后端直接关联这些
+   * plan 渲染、不再重新选片，保证预览所见即成片。后端未支持时忽略该字段。
+   */
+  variant_plan_ids?: string[]
 }
 
 /** 单个生成任务详情（对齐后端 GenerationTaskResponse） */

apps/web/src/api/templates/types.ts

@@ -42,8 +42,10 @@ export interface TemplateItem {
 export interface TemplateSegment {
   id?: string
   segment_order: number
-  duration_min: number
-  duration_max: number
+  /** @deprecated 模板无时长概念（#1750 基线）：字段保留仅为兼容旧数据读取 */
+  duration_min?: number
+  /** @deprecated 同上 */
+  duration_max?: number
   material_type: string | null
   description?: string
 }
@@ -55,8 +57,6 @@ export interface TemplateListParams {
   category?: string
   tags?: string
   keyword?: string
-  /** 时长筛选（秒）：short < 30, medium 30-120, long > 120 */
-  duration_range?: "short" | "medium" | "long"
 }
 
 /** 模板列表分页响应 */

apps/web/src/pages/editing-planner/hooks/template-management/usePlanLoading.ts

@@ -108,7 +108,10 @@ export function usePlanLoading({
             id: `seg-${idx}`,
             template_segment_id: `seg-${idx}`,
             type: (seg.material_type === "voiceover" ? "voice" : "pip") as ClipType,
-            duration: (seg.duration_min + seg.duration_max) / 2,
+            duration:
+              seg.duration_min != null && seg.duration_max != null
+                ? (seg.duration_min + seg.duration_max) / 2
+                : 5,
             startOffset: 0,
             script_text: "",
             order: seg.segment_order,

apps/web/src/pages/editing-planner/hooks/template-management/useTemplateDetail.ts

@@ -43,7 +43,10 @@ export function useTemplateDetail({
           id: seg.id || `seg-${idx}`,
           template_segment_id: seg.id || `seg-${idx}`,
           type: (seg.material_type === "voiceover" ? "voice" : "pip") as ClipType,
-          duration: (seg.duration_min + seg.duration_max) / 2,
+          duration:
+            seg.duration_min != null && seg.duration_max != null
+              ? (seg.duration_min + seg.duration_max) / 2
+              : 5,
           startOffset: 0,
           script_text: "",
           order: seg.segment_order,

apps/web/src/pages/generate/GeneratePage.tsx

@@ -27,6 +27,8 @@ import { useStepNavigation } from "./hooks/useStepNavigation"
 import { useGenerateVideo } from "./hooks/useGenerateVideo"
 
 import { usePreviewAssets } from "./hooks/usePreviewAssets"
+import { useBatchVariantPlans } from "./hooks/useBatchVariantPlans"
+import { useVariantVoicePreview } from "./hooks/useVariantVoicePreview"
 import { useTitleStyleUpdaters } from "./hooks/useStep4Title/useTitleStyleUpdaters"
 import { getAssetsByKind } from "@/api/assets"
 import { previewTts } from "@/api/tts"
@@ -136,14 +138,17 @@ const GeneratePage: React.FC = () => {
   const variant0Title = isBatch ? previewTitles?.[0] || "" : ""
 
   useEffect(() => {
+    // #1750：批量模式每变体独立/共用配音由 useVariantVoicePreview 接管（含独立模式每卡片挂各自 URL），
+    // 本 effect 只服务单视频，批量模式直接跳过（避免共用 TTS 结果错误下发给所有变体）
+    if (isBatch) return
     const voiceAsset = voiceMaterials.find((m) => m.id === selectedVoice)
     if (voiceAsset?.file_url) {
       setPreviewVoiceAudioUrl(voiceAsset.file_url)
       return
     }
 
-    // 批量模式下 TTS 文案跟随变体0标题；单视频跟随主标题
-    const ttsTitle = isBatch ? variant0Title || "" : titleSettings.title
+    // 单视频 TTS 文案跟随主标题
+    const ttsTitle = titleSettings.title
     const voiceId = selectedClonedVoice || selectedVoice
     if (!voiceId || !ttsTitle) {
       setPreviewVoiceAudioUrl(null)
@@ -213,14 +218,56 @@ const GeneratePage: React.FC = () => {
 
   /* ── 加载素材详情（供前端预览播放器使用） ── */
   const previewAssetsEnabled = previewAssetIds.length > 0
-  const { assets: previewAssets, ready: previewAssetsReady } = usePreviewAssets(
-    previewAssetIds,
-    previewAssetsEnabled,
-  )
+  const {
+    assets: previewAssets,
+    ready: previewAssetsReady,
+    ensureAssets,
+  } = usePreviewAssets(previewAssetIds, previewAssetsEnabled)
 
   /* ── 预览就绪：纯前端 Canvas 预览，素材详情加载完即可秒开（单视频/批量一致） ── */
   const previewReady = previewAssetsReady && !!currentTemplate
 
+  /* ── 批量变体真实片段（#1744）：后端独立选片，预览即成片；失败静默降级本地模拟 ──
+     仅批量（N>1）且在第 4 步预览时申请，避免选素材阶段频繁请求；
+     变体 0 沿用草稿 plan（与单视频一致），变体 1..N-1 后端 reselect 独立选片 */
+  const {
+    clipsByVariant: variantClips,
+    planIdsByVariant: variantPlanIds,
+    loading: variantClipsLoading,
+    error: variantClipsError,
+    retry: retryVariantClips,
+  } = useBatchVariantPlans({
+    enabled: isBatch && currentStep === 4 && previewAssetsReady,
+    count: previewCount,
+    templateId: selectedTemplate || "",
+    assetIds: previewAssetIds,
+    sourcePlanId: storedSourceEditPlanId || sourceEditPlanId || "",
+  })
+
+  /* ── 批量变体配音预览 URL（#1750）：独立模式每变体挂各自配音，共用模式全挂同一条；
+     hook 内部自取配音素材库并做 TTS 缓存/串行/防竞态 */
+  const variantVoiceAudioUrls = useVariantVoicePreview({
+    enabled: isBatch,
+    count: previewCount,
+    perVideo: voiceModePerVideo,
+    sharedVoiceId: selectedVoice || "",
+    clonedVoiceId: selectedClonedVoice || "",
+    variantVoiceIds: voiceLibraryIds || [],
+    titles: previewTitles || [],
+  })
+
+  /* ── 变体计划 clips 引用的素材可能不在已选列表中（#1750）：差集补拉素材详情，
+     保证播放器拿得到 file_url，而不是静默丢片段/用假数据冒充 */
+  const clipAssetIds = useMemo(() => {
+    if (!isBatch || !variantClips?.length) return []
+    const ids = new Set<string>()
+    variantClips.forEach((list) => list.forEach((c) => c.asset_id && ids.add(c.asset_id)))
+    return Array.from(ids)
+  }, [isBatch, variantClips])
+  useEffect(() => {
+    if (clipAssetIds.length > 0) void ensureAssets(clipAssetIds)
+  }, [clipAssetIds, ensureAssets])
+
   /* ── 勾选变体 ── */
   const toggleVariantSelect = useCallback(
     (index: number) => {
@@ -262,6 +309,8 @@ const GeneratePage: React.FC = () => {
     autoSubtitles,
     bgm,
     sourceEditPlanId: storedSourceEditPlanId || sourceEditPlanId,
+    // #1744：批量预览阶段后端为每个变体生成的独立 plan id，正式生成回传 → 预览即成片
+    variantPlanIds,
     previewTaskId,
     bgmConfig,
     previewCount,
@@ -371,7 +420,9 @@ const GeneratePage: React.FC = () => {
   const layoutClassName = useMemo(() => {
     if (currentStep < 4) return "xx-generate-layout full-width"
     if (currentStep === 4) return "xx-generate-layout step4-layout"
-    // 步骤5/6：批量网格需要整行宽度；单视频保持 表单+右侧成片 两栏
+    // 步骤5：全宽+内容居中（单视频视频播放器居中，批量网格居中）
+    if (currentStep === 5) return "xx-generate-layout full-width"
+    // 步骤6：封面选择保持两栏布局
     return isBatch ? "xx-generate-layout full-width" : "xx-generate-layout"
   }, [currentStep, isBatch])
 
@@ -393,7 +444,6 @@ const GeneratePage: React.FC = () => {
               /* 单视频：前端 Canvas 实时预览（与旧版一致，零回归） */
               <FrontendPreviewPlayer
                 assets={previewAssets}
-                template={currentTemplate}
                 videoRatio={videoRatio}
                 ready={previewAssets.length > 0}
                 serverClips={serverClips}
@@ -425,11 +475,14 @@ const GeneratePage: React.FC = () => {
                 <CanvasPreviewGrid
                   count={previewCount}
                   assets={previewAssets}
-                  template={currentTemplate}
                   videoRatio={videoRatio}
                   titles={previewTitles}
                   titleSettings={titleSettings}
-                  voiceAudioUrl={previewVoiceAudioUrl || undefined}
+                  voiceAudioUrls={variantVoiceAudioUrls}
+                  variantClips={variantClips}
+                  clipsLoading={variantClipsLoading}
+                  clipsError={variantClipsError}
+                  onRetryClips={retryVariantClips}
                   selectedIds={selectedVariantIds}
                   onToggleSelect={toggleVariantSelect}
                   selectable={!generating}
@@ -502,17 +555,88 @@ const GeneratePage: React.FC = () => {
             generateError={generateError}
             selectedCount={isBatch ? selectedVariantIds.length : 1}
           />
+
+          {/* ════ 步骤5（单视频）：成片播放器内联居中（#1761） ════ */}
+          {currentStep === 5 && !isBatch && generated && finalVideo && (
+            <div
+              style={{
+                display: "flex",
+                justifyContent: "center",
+                marginTop: 16,
+              }}
+            >
+              <div
+                style={{
+                  display: "flex",
+                  flexDirection: "column",
+                  alignItems: "center",
+                  background: "#000",
+                  borderRadius: 12,
+                  padding: 8,
+                  maxWidth: 320,
+                  width: "100%",
+                }}
+              >
+                <video
+                  src={finalVideo.download_url || finalVideo.file_url}
+                  controls
+                  style={{
+                    width: "auto",
+                    maxWidth: "100%",
+                    maxHeight: "70vh",
+                    aspectRatio: "9 / 16",
+                    objectFit: "contain",
+                    borderRadius: 8,
+                  }}
+                  poster={finalVideo.thumbnail_url || undefined}
+                />
+                <div style={{ display: "flex", gap: 8, marginTop: 12, justifyContent: "center" }}>
+                  <button className="xx-btn xx-btn-ghost xx-btn-sm" onClick={handleDownload}>
+                    ⬇️ 下载
+                  </button>
+                  <button className="xx-btn xx-btn-ghost xx-btn-sm" onClick={handleShare}>
+                    🔗 分享
+                  </button>
+                  <button
+                    className="xx-btn xx-btn-ghost xx-btn-sm"
+                    onClick={() => navigate("/app/products")}
+                  >
+                    📁 前往成片库
+                  </button>
+                </div>
+              </div>
+            </div>
+          )}
         </div>
 
-        {/* ════ 步骤5/6（单视频）：右侧成片播放器 ════ */}
-        {currentStep >= 5 && !isBatch && generated && finalVideo && (
+        {/* ════ 步骤6（单视频）：右侧成片播放器 ════ */}
+        {currentStep >= 6 && !isBatch && generated && finalVideo && (
           <div className="xx-generate-right-col">
-            <div className="xx-inline-video-player">
+            <div
+              className="xx-inline-video-player"
+              style={{
+                display: "flex",
+                justifyContent: "center",
+                alignItems: "center",
+                background: "#000",
+                borderRadius: 12,
+                padding: 8,
+              }}
+            >
               <video
                 src={finalVideo.download_url || finalVideo.file_url}
                 controls
                 autoPlay={currentStep === 5}
-                style={{ width: "100%", maxHeight: "70vh", objectFit: "contain", borderRadius: 12 }}
+                // 竖屏自适应（#1750）：成片固定 1080×1920（9:16），元数据到达前按 9:16 占位，
+                // 到达后浏览器按真实宽高比 contain；黑底居中杜绝左右大黑边
+                style={{
+                  width: "auto",
+                  maxWidth: "100%",
+                  maxHeight: "70vh",
+                  aspectRatio: "9 / 16",
+                  objectFit: "contain",
+                  borderRadius: 8,
+                }}
                 poster={finalVideo.thumbnail_url || undefined}
               />
               <div style={{ display: "flex", gap: 8, marginTop: 12, justifyContent: "center" }}>

apps/web/src/pages/generate/components/BatchGenerationGrid.tsx

@@ -34,12 +34,26 @@ const BatchGenerationGrid: React.FC<BatchGenerationGridProps> = ({
           完成 {tasks.filter((t) => t.status === "completed").length} / {tasks.length}
         </span>
       </div>
-      <div className="xx-batch-gen-grid">
+      <div
+        className="xx-batch-gen-grid"
+        style={{
+          display: "grid",
+          gridTemplateColumns: "repeat(auto-fill, minmax(160px, 180px))",
+          justifyContent: "center",
+          justifyItems: "center",
+          gap: 14,
+          width: "100%",
+        }}
+      >
         {sorted.map((task) => {
           const title = titles[task.variantIndex] || `视频 ${task.variantIndex + 1}`
           const video = (task.videos?.[0] || null) as GeneratedVideo | null
           return (
-            <div key={task.taskId} className={`xx-batch-gen-card status-${task.status}`}>
+            <div
+              key={task.taskId}
+              className={`xx-batch-gen-card status-${task.status}`}
+              style={{ maxWidth: 240 }}
+            >
               <div className="xx-batch-gen-card-head">
                 <span className="xx-batch-gen-card-title" title={title}>
                   {task.status === "completed" ? (
@@ -66,12 +80,32 @@ const BatchGenerationGrid: React.FC<BatchGenerationGridProps> = ({
                   </>
                 )}
                 {task.status === "completed" && video && (
-                  <video
-                    src={video.download_url || video.file_url}
-                    controls
-                    style={{ width: "100%", borderRadius: 8, background: "#000", maxHeight: 280 }}
-                    poster={video.thumbnail_url}
-                  />
+                  // 竖屏自适应容器（#1750）：成片固定 1080×1920（9:16），
+                  // 视频按真实宽高比 contain 显示，黑底居中，杜绝横屏播放器左右大黑边
+                  <div
+                    style={{
+                      display: "flex",
+                      justifyContent: "center",
+                      alignItems: "center",
+                      background: "transparent",
+                      borderRadius: 8,
+                      padding: 0,
+                    }}
+                  >
+                    <video
+                      src={video.download_url || video.file_url}
+                      controls
+                      style={{
+                        width: "100%",
+                        maxHeight: "70vh",
+                        aspectRatio: "9 / 16",
+                        objectFit: "cover",
+                        borderRadius: 4,
+                        background: "transparent",
+                      }}
+                      poster={video.thumbnail_url}
+                    />
+                  </div>
                 )}
                 {task.status === "completed" && !video && (
                   <div className="xx-batch-gen-card-done">✅ 已完成（成片可在下一步选择封面）</div>

apps/web/src/pages/generate/components/CanvasPreviewGrid.tsx

@@ -1,27 +1,47 @@
 /**
- * 批量前端 Canvas 实时预览网格（Issue #1677 修正方案）
+ * 批量前端 Canvas 实时预览网格（Issue #1677 起，#1750 对齐基线：只播放后端真实计划）
  *
  * N 个 FrontendPreviewPlayer 网格排列：
- * - 纯前端 Canvas + video 元素实时播放素材片段，不调任何后端渲染接口
- * - variantSeed 让每个变体素材排布/起始点不同，画面有可见差异
- * - 各自叠加独立标题浮层（variantTitle），标题样式全局共用
- * - 勾选框决定提交时生成哪些变体
+ * - 纯前端 Canvas + video 元素实时播放素材片段，不调任何后端渲染接口；
+ * - #1744/#1750：片段只来自后端变体计划接口（POST /generation/variant-plans）的真实
+ *   clips，与正式批量生成同源自 reselect_plan_for_variant，预览即成片；
+ *   接口失败/数据不完整 → 整网格显示错误态+重试（严禁本地假数据冒充预览）；
+ *   加载中 → 9:16 占位防塌陷；
+ * - 各自叠加独立标题浮层（variantTitle），标题样式全局共用；
+ * - 勾选框决定提交时生成哪些变体；
+ * - 每个变体挂载各自配音 URL（独立模式 #1750）或共用同一条；播放互斥：
+ *   点击某卡片播放时其他卡片自动暂停，同一时刻只有一路声音（#1741）。
  */
-import React from "react"
+import React, { useState } from "react"
 import type { AssetItem } from "@/api/assets"
-import type { EditingTemplate } from "@/api/editing-planner"
+import type { EditPlanClip } from "@/api/template-editor"
+import { LoadingOutlined, ReloadOutlined } from "@ant-design/icons"
+import { Button } from "antd"
 import type { TitleSettings } from "../types"
 import FrontendPreviewPlayer from "./FrontendPreviewPlayer"
 
 interface CanvasPreviewGridProps {
   count: number
   assets: AssetItem[]
-  template: EditingTemplate | null
   videoRatio: string
   titles: string[]
   titleSettings: TitleSettings
-  /** 共用配音预览音频（仅第 1 个变体播放，避免多路音频重叠） */
-  voiceAudioUrl?: string
+  /**
+   * 各变体配音预览音频 URL（#1750：独立配音模式每变体一条；共用模式全为同一条；
+   * 元素为 null 表示该变体暂无音频（AI 音色 TTS 合成中））
+   */
+  voiceAudioUrls?: (string | null)[]
+  /**
+   * 各变体的后端真实片段（#1744/#1750）：长度=count。
+   * 仅 clipsLoading=false 且 clipsError=false 时才会传给播放器。
+   */
+  variantClips?: EditPlanClip[][]
+  /** 是否正在向后端申请变体计划 */
+  clipsLoading?: boolean
+  /** 申请变体计划失败（端点未上线/网络错误/数据不完整）：显示错误态，严禁假数据 */
+  clipsError?: boolean
+  /** 用户点击错误态「重试」 */
+  onRetryClips?: () => void
   /** 勾选的变体序号 */
   selectedIds: number[]
   onToggleSelect: (index: number) => void
@@ -32,15 +52,21 @@ interface CanvasPreviewGridProps {
 const CanvasPreviewGrid: React.FC<CanvasPreviewGridProps> = ({
   count,
   assets,
-  template,
   videoRatio,
   titles,
   titleSettings,
-  voiceAudioUrl,
+  voiceAudioUrls,
+  variantClips,
+  clipsLoading = false,
+  clipsError = false,
+  onRetryClips,
   selectedIds,
   onToggleSelect,
   selectable = true,
 }) => {
+  // ── 播放互斥（#1741）：同一时刻只有一个卡片持有播放权（token = 变体序号，0 起，#1750） ──
+  const [activePlayToken, setActivePlayToken] = useState<number | null>(null)
+
   // count 上限已在源头 PreviewCountModal 的数量选择（1~MAX_PREVIEW_COUNT=10）clamp，
   // 这里完整渲染所有变体，保证每个变体都有勾选/预览入口，UI 与数据不脱节
   return (
@@ -64,29 +90,54 @@ const CanvasPreviewGrid: React.FC<CanvasPreviewGridProps> = ({
                 <span>视频 {i + 1}</span>
               </label>
             </div>
-            <FrontendPreviewPlayer
-              assets={assets}
-              template={template}
-              videoRatio={videoRatio}
-              ready={assets.length > 0}
-              variantSeed={i + 1}
-              variantTitle={titles[i] || ""}
-              voiceAudioUrl={i === 0 ? voiceAudioUrl : undefined}
-              compact
-              titleSettings={{
-                title: titles[i] || "",
-                size: titleSettings.size,
-                font: titleSettings.font,
-                color: titleSettings.color,
-                position: titleSettings.position as "top" | "center" | "bottom" | "custom",
-                bold: titleSettings.bold,
-                italic: titleSettings.italic,
-                stroke: titleSettings.stroke,
-                shadow: titleSettings.shadow,
-                posX: titleSettings.posX,
-                posY: titleSettings.posY,
-              }}
-            />
+            {clipsError ? (
+              // ── 错误态（#1750）：9:16 占位防塌陷，不渲染任何播放器（严禁假数据） ──
+              <div className="xx-variant-clips-status" role="alert">
+                <span className="xx-variant-clips-error-text">预览加载失败，请重试</span>
+                {i === 0 && onRetryClips ? (
+                  <Button
+                    size="small"
+                    icon={<ReloadOutlined />}
+                    onClick={onRetryClips}
+                    style={{ marginTop: 12 }}
+                  >
+                    重试
+                  </Button>
+                ) : null}
+              </div>
+            ) : clipsLoading || !variantClips?.[i]?.length ? (
+              // ── 加载态：9:16 占位防塌陷 ──
+              <div className="xx-variant-clips-status" aria-label={`变体${i + 1}片段加载中`}>
+                <LoadingOutlined />
+                <span style={{ marginTop: 8 }}>独立选片中…</span>
+              </div>
+            ) : (
+              <FrontendPreviewPlayer
+                assets={assets}
+                videoRatio={videoRatio}
+                ready={assets.length > 0}
+                playToken={i}
+                serverClips={variantClips[i]}
+                variantTitle={titles[i] || ""}
+                voiceAudioUrl={voiceAudioUrls?.[i] || undefined}
+                activePlayToken={activePlayToken}
+                onPlayTokenChange={setActivePlayToken}
+                compact
+                titleSettings={{
+                  title: titles[i] || "",
+                  size: titleSettings.size,
+                  font: titleSettings.font,
+                  color: titleSettings.color,
+                  position: titleSettings.position as "top" | "center" | "bottom" | "custom",
+                  bold: titleSettings.bold,
+                  italic: titleSettings.italic,
+                  stroke: titleSettings.stroke,
+                  shadow: titleSettings.shadow,
+                  posX: titleSettings.posX,
+                  posY: titleSettings.posY,
+                }}
+              />
+            )}
           </div>
         )
       })}

apps/web/src/pages/generate/components/FrontendPreviewPlayer.tsx

@@ -13,18 +13,19 @@ import {
   PauseCircleOutlined,
   SoundOutlined,
   LoadingOutlined,
+  AudioOutlined,
+  AudioMutedOutlined,
 } from "@ant-design/icons"
 import type { AssetItem } from "@/api/assets"
-import type { EditingTemplate } from "@/api/editing-planner"
 import type { EditPlanClip } from "@/api/template-editor"
 import { useSegmentScheduler, type PlaybackSegment } from "../hooks/useSegmentScheduler"
 import { useCanvasPlayer } from "../hooks/useCanvasPlayer"
 
 interface FrontendPreviewPlayerProps {
   assets: AssetItem[]
-  template: EditingTemplate | null
   videoRatio: string
   ready: boolean
+  /** 服务端变体计划真实片段（#1750：必填，无 fallback；批量网格传入各变体自己的 clips） */
   serverClips?: EditPlanClip[]
   voiceAudioUrl?: string
   titleSettings?: {
@@ -42,15 +43,21 @@ interface FrontendPreviewPlayerProps {
   }
   onTitlePositionChange?: (posX: number, posY: number) => void
   /**
-   * 变体种子（批量生成 #1677）：同一批素材在不同变体中采用不同的素材顺序与
-   * 片段起始点，让 N 个 Canvas 预览画面有差异（纯前端随机剪辑模拟，不调后端）。
-   * 0 / 不传 = 单视频，排布与旧版完全一致（零回归）。
+   * 播放互斥 token（#1750）：批量网格中为变体序号（0 起），单视频不传。
+   * 持有播放权的实例播放，其余自动暂停。
    */
-  variantSeed?: number
+  playToken?: number
   /** 变体标题文字（批量时每个预览独立标题，叠加在画面上）；不传用 titleSettings.title */
   variantTitle?: string
   /** 紧凑模式（批量网格中使用，缩小内边距/标题尺寸） */
   compact?: boolean
+  /**
+   * 批量网格播放互斥（#1741/#1750）：当前持有播放权的实例 token（变体序号）。
+   * 持有权变化且不等于自身时，本实例自动暂停（视频+配音）。单视频模式不传。
+   */
+  activePlayToken?: number | null
+  /** 播放权变化回调：本实例请求播放时传自身 playToken，暂停时传 null */
+  onPlayTokenChange?: (token: number | null) => void
 }
 
 function formatTime(seconds: number): string {
@@ -60,114 +67,107 @@ function formatTime(seconds: number): string {
 }
 
 /**
- * 将素材映射为播放片段（复用原逻辑）
+ * 将后端变体计划 clips 映射为播放片段（#1750：唯一数据来源，无本地模拟 fallback）
+ *
+ * 预览不渲染：浏览器按后端真实计划即时播放素材原片，预览即成片。
+ * 模板片段数固定、成片时长=配音时长（后端等比分配），前端不再有任何时长假设。
  */
-/** 简单可复现随机数（mulberry32），同一种子产出稳定排布，避免每次渲染抖动 */
-function seededRandom(seed: number): () => number {
-  let a = seed >>> 0
-  return () => {
-    a |= 0
-    a = (a + 0x6d2b79f5) | 0
-    let t = Math.imul(a ^ (a >>> 15), 1 | a)
-    t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t
-    return ((t ^ (t >>> 14)) >>> 0) / 4294967296
-  }
-}
-
 function buildPlaybackSegments(
   assets: AssetItem[],
-  template: EditingTemplate | null,
   serverClips?: EditPlanClip[],
-  variantSeed = 0,
+  /** #1754 前端兜底：配音时长≠clips 总时长时，按比例缩放每段播放时长并调速 */
+  speedFactor = 1,
 ): PlaybackSegment[] {
-  if (!assets.length) return []
+  if (!assets.length || !serverClips || serverClips.length === 0) return []
 
-  // Build asset lookup map
   const assetMap = new Map(assets.map((a) => [a.id, a]))
-
-  // 优先使用服务端 clips（含随机 start_time 和正确数量），与最终生成结果一致
-  if (serverClips && serverClips.length > 0) {
-    const segments: PlaybackSegment[] = []
-    for (const clip of serverClips) {
-      const asset = assetMap.get(clip.asset_id)
-      if (!asset) continue
-      const assetDuration = asset.duration || asset.metadata?.duration || 30
-      const startTime = clip.start_time || 0
-      const endTime = Math.min(startTime + (clip.duration || assetDuration), assetDuration)
-      const videoUrl = asset.file_url || asset.storage_key
-      segments.push({ assetId: asset.id, videoUrl, startTime, endTime, order: clip.order })
-    }
-    if (segments.length > 0) {
-      return segments.sort((a, b) => a.order - b.order)
-    }
-  }
-
-  // Fallback: 本地构建片段
-  // variantSeed=0（单视频）：与旧行为完全一致（素材原序、起始点 0），零回归
-  // variantSeed>0（批量变体）：素材顺序按种子轮换 + 片段起始点在素材内偏移，
-  //   模拟后端"AI 随机剪辑出不同版本"，让 N 个预览画面有可见差异
-  const templateSegments = template?.segments || []
   const segments: PlaybackSegment[] = []
-  const orderedAssets = variantSeed > 0 ? [...assets] : assets
-  if (variantSeed > 0 && orderedAssets.length > 1) {
-    const rand = seededRandom(variantSeed * 7919 + 13)
-    // 素材轮换：把数组旋转 (seed % n) 位，再对后半段做一次稳定交换
-    const n = orderedAssets.length
-    const rotate = variantSeed % n
-    orderedAssets.push(...orderedAssets.splice(0, rotate))
-    const swapA = Math.floor(rand() * n)
-    const swapB = Math.floor(rand() * n)
-    if (swapA !== swapB) {
-      ;[orderedAssets[swapA], orderedAssets[swapB]] = [orderedAssets[swapB], orderedAssets[swapA]]
-    }
-  }
-
-  orderedAssets.forEach((asset, i) => {
-    const assetDuration = asset.duration || asset.metadata?.duration || 30
-    const tplSeg = templateSegments[i] || templateSegments[templateSegments.length - 1]
-    const segDuration = tplSeg
-      ? Math.min(tplSeg.duration_max, Math.max(tplSeg.duration_min, assetDuration))
-      : Math.min(assetDuration, 10)
-
-    let startTime = 0
-    if (variantSeed > 0 && assetDuration - segDuration > 1) {
-      const rand = seededRandom(variantSeed * 104729 + i * 31 + 7)
-      // 起始点在素材可用区间内随机偏移（至少留 0.5s 余量）
-      const maxStart = Math.max(0, assetDuration - segDuration - 0.5)
-      startTime = Math.round(rand() * maxStart * 10) / 10
-    }
-    const endTime = Math.min(startTime + segDuration, assetDuration)
+  // speedFactor > 1 表示 clips 偏短需加速；< 1 表示 clips 偏长需减速
+  const invSpeed = speedFactor > 0 && Math.abs(speedFactor - 1) > 0.01 ? 1 / speedFactor : 1
+  for (const clip of serverClips) {
+    const asset = assetMap.get(clip.asset_id)
+    if (!asset) continue
+    const assetDuration = asset.duration || asset.metadata?.duration || 0
+    const startTime = clip.start_time || 0
+    // 片段时长以后端计划为准（配音时长等比分配）；素材时长仅用于兜底钳制边界
+    const rawClipDuration = clip.duration || 0
+    // #1754：按 speedFactor 缩放片段时长，使总时长匹配配音
+    const clipDuration = invSpeed !== 1 ? rawClipDuration * invSpeed : rawClipDuration
+    const endTime =
+      assetDuration > 0
+        ? Math.min(startTime + clipDuration, assetDuration)
+        : startTime + clipDuration
     const videoUrl = asset.file_url || asset.storage_key
-
-    segments.push({ assetId: asset.id, videoUrl, startTime, endTime, order: i })
-  })
-
-  return segments
+    segments.push({
+      assetId: asset.id,
+      videoUrl,
+      startTime,
+      endTime,
+      order: clip.order,
+      playbackRate: invSpeed !== 1 ? speedFactor : undefined,
+    })
+  }
+  return segments.sort((a, b) => a.order - b.order)
 }
 
 const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
   assets,
-  template,
   videoRatio,
   ready,
   serverClips,
   voiceAudioUrl,
   titleSettings,
   onTitlePositionChange,
-  variantSeed = 0,
+  playToken,
   variantTitle,
   compact = false,
+  activePlayToken = null,
+  onPlayTokenChange,
 }) => {
+  // #1754：测量配音时长，计算缩放因子
+  const [voiceDuration, setVoiceDuration] = useState(0)
+  useEffect(() => {
+    if (!voiceAudioUrl) {
+      setVoiceDuration(0)
+      return
+    }
+    const audio = new Audio()
+    audio.preload = "metadata"
+    const onLoaded = () => {
+      if (audio.duration && isFinite(audio.duration)) {
+        setVoiceDuration(audio.duration)
+      }
+    }
+    audio.addEventListener("loadedmetadata", onLoaded)
+    audio.src = voiceAudioUrl
+    return () => {
+      audio.removeEventListener("loadedmetadata", onLoaded)
+    }
+  }, [voiceAudioUrl])
+
+  // #1756：clips 原始总时长 + 转场时长（后端等比分配配音时包含转场占位）
+  const rawClipsDuration = useMemo(() => {
+    if (!serverClips?.length) return 0
+    return serverClips.reduce((sum, c) => sum + (c.duration || 0) + (c.transition_duration || 0), 0)
+  }, [serverClips])
+
+  // #1754→#1756：配音时长可用且与 clips+转场 总时长偏差 > 5% 时，按比例调速
+  const speedFactor = useMemo(() => {
+    if (!voiceDuration || voiceDuration <= 0 || rawClipsDuration <= 0) return 1
+    const ratio = rawClipsDuration / voiceDuration
+    return Math.abs(ratio - 1) > 0.05 ? ratio : 1
+  }, [voiceDuration, rawClipsDuration])
+
   const segments = useMemo(
-    () => buildPlaybackSegments(assets, template, serverClips, variantSeed),
-    [assets, template, serverClips, variantSeed],
+    () => buildPlaybackSegments(assets, serverClips, speedFactor),
+    [assets, serverClips, speedFactor],
   )
   // 批量变体：标题文字取 variantTitle，样式仍由全局 titleSettings 控制
   const effectiveTitle = variantTitle ?? titleSettings?.title
 
   // ── ASS 坐标系参数（与后端 ass_subtitle_builder.py 一致） ──
-  const TITLE_MARGIN_TOP = 120
-  const TITLE_MARGIN_BOTTOM = 60
+  const TITLE_MARGIN_TOP = 180
+  const TITLE_MARGIN_BOTTOM = 100
   const TITLE_MARGIN_SIDE = 40
   const playRes = (() => {
     switch (videoRatio) {
@@ -339,6 +339,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
     canPlay: videoCanPlay,
     togglePlayPause: videoTogglePlayPause,
     seekTo: videoSeekTo,
+    pause: videoPause,
     videoRefs,
   } = useSegmentScheduler(segments)
 
@@ -353,6 +354,10 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
   // ── 配音音频同步 ──
   const audioRef = useRef<HTMLAudioElement | null>(null)
   const prevIsPlayingRef = useRef(false)
+  // 本卡片静音开关（#1741）：默认有声，用户可点喇叭单独静音某张卡片
+  const [muted, setMuted] = useState(false)
+  // 有配音时 video 素材保持静音（避免原声与配音混音）；无配音时取消静音，素材原声兜底
+  const hasVoice = !!voiceAudioUrl
 
   useEffect(() => {
     if (!voiceAudioUrl) {
@@ -370,7 +375,8 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
     if (audioRef.current.src !== voiceAudioUrl) {
       audioRef.current.src = voiceAudioUrl
     }
-  }, [voiceAudioUrl])
+    audioRef.current.muted = muted
+  }, [voiceAudioUrl, muted])
 
   useEffect(() => {
     const audio = audioRef.current
@@ -409,17 +415,42 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
     [effectiveUseWebCodecs, canvasControls, videoSeekTo],
   )
 
+  // ── 批量网格播放互斥（#1741）：播放权属于其他实例时，本实例自动暂停（视频+配音） ──
+  useEffect(() => {
+    if (activePlayToken == null || playToken == null || activePlayToken === playToken) return
+    if (effectiveUseWebCodecs) {
+      if (canvasState.isPlaying) canvasControls.pause()
+    } else if (isPlaying) {
+      videoPause()
+    }
+    // isPlaying/canvasState.isPlaying 不放依赖：只在 token 变化时执行一次暂停，
+    // token 等于自身时本实例的播放在 handleTogglePlay 里处理
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [activePlayToken, playToken, effectiveUseWebCodecs])
+
   const handleTogglePlay = useCallback(() => {
     if (effectiveUseWebCodecs) {
       if (canvasState.isPlaying) {
         canvasControls.pause()
+        onPlayTokenChange?.(null)
       } else {
+        if (playToken != null) onPlayTokenChange?.(playToken)
         canvasControls.play()
       }
     } else {
+      // video fallback：先上报播放权（暂停其他卡片），再切换本卡片播放/暂停
+      if (playToken != null) onPlayTokenChange?.(isPlaying ? null : playToken)
       videoTogglePlayPause()
     }
-  }, [effectiveUseWebCodecs, canvasState.isPlaying, canvasControls, videoTogglePlayPause])
+  }, [
+    effectiveUseWebCodecs,
+    canvasState.isPlaying,
+    canvasControls,
+    videoTogglePlayPause,
+    isPlaying,
+    playToken,
+    onPlayTokenChange,
+  ])
 
   // ── 进度条拖拽 ──
   const [isDragging, setIsDragging] = useState(false)
@@ -573,7 +604,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
         maxWidth: compact ? "100%" : 280,
         margin: compact ? 0 : "0 auto",
         aspectRatio: "9 / 16",
-        background: "#0a0a0a",
+        background: compact ? "transparent" : "#0a0a0a",
         borderRadius: compact ? 10 : 24,
         overflow: "hidden",
         boxShadow: compact
@@ -597,7 +628,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
             style={{
               width: "100%",
               height: "100%",
-              objectFit: "contain",
+              objectFit: "cover",
             }}
           />
         </div>
@@ -608,7 +639,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
         segments.map((seg, i) => (
           <video
             key={seg.assetId}
-            muted
+            muted={hasVoice || muted}
             ref={(el) => {
               videoRefs.current[i] = el
             }}
@@ -619,7 +650,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
               inset: 0,
               width: "100%",
               height: "100%",
-              objectFit: "contain",
+              objectFit: "cover",
               background: "#000",
               zIndex: 1,
               opacity: i === videoCurrentSegIdx ? 1 : 0,
@@ -662,8 +693,8 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
                         ? { top: "50%", transform: "translate(-50%, -50%)" }
                         : { bottom: `${titleBottomPct}%` }),
                   }),
-              pointerEvents: onTitlePositionChange && variantSeed === 0 ? "auto" : "none",
-              cursor: onTitlePositionChange && variantSeed === 0 ? "grab" : "default",
+              pointerEvents: onTitlePositionChange && playToken == null ? "auto" : "none",
+              cursor: onTitlePositionChange && playToken == null ? "grab" : "default",
               touchAction: "none",
               userSelect: "none",
               WebkitUserSelect: "none",
@@ -743,6 +774,45 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
         </button>
       )}
 
+      {/* 静音/有声切换（#1741）：左上角，默认有声；批量与单视频均可单独静音 */}
+      {segments.length > 0 && (
+        <button
+          type="button"
+          aria-label={muted ? "取消静音" : "静音"}
+          title={muted ? "取消静音" : "静音"}
+          onClick={() => setMuted((m) => !m)}
+          style={{
+            position: "absolute",
+            top: 8,
+            left: 8,
+            width: compact ? 26 : 30,
+            height: compact ? 26 : 30,
+            display: "flex",
+            alignItems: "center",
+            justifyContent: "center",
+            background: "rgba(0,0,0,0.45)",
+            backdropFilter: "blur(8px)",
+            WebkitBackdropFilter: "blur(8px)",
+            border: "1px solid rgba(255,255,255,0.1)",
+            borderRadius: "50%",
+            color: muted ? "rgba(255,255,255,0.45)" : "rgba(255,255,255,0.92)",
+            fontSize: compact ? 13 : 15,
+            cursor: "pointer",
+            zIndex: 10,
+            padding: 0,
+            transition: "background 0.15s, color 0.15s",
+          }}
+          onMouseEnter={(e) => {
+            e.currentTarget.style.background = "rgba(0,0,0,0.65)"
+          }}
+          onMouseLeave={(e) => {
+            e.currentTarget.style.background = "rgba(0,0,0,0.45)"
+          }}
+        >
+          {muted ? <AudioMutedOutlined /> : <AudioOutlined />}
+        </button>
+      )}
+
       {/* 片段指示器 — 右上角胶囊 */}
       <div
         style={{
@@ -753,9 +823,9 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
           backdropFilter: "blur(8px)",
           WebkitBackdropFilter: "blur(8px)",
           color: "rgba(255,255,255,0.9)",
-          fontSize: 10,
+          fontSize: compact ? 9 : 10,
           fontWeight: 500,
-          padding: "2px 8px",
+          padding: compact ? "1px 6px" : "2px 8px",
           borderRadius: 999,
           zIndex: 10,
           border: "1px solid rgba(255,255,255,0.1)",
@@ -774,8 +844,8 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
           right: 0,
           display: "flex",
           alignItems: "center",
-          gap: 10,
-          padding: "12px 16px 16px",
+          gap: compact ? 6 : 10,
+          padding: compact ? "8px 10px 10px" : "12px 16px 16px",
           background: "linear-gradient(transparent, rgba(0,0,0,0.7))",
           backdropFilter: "blur(4px)",
           WebkitBackdropFilter: "blur(4px)",
@@ -788,10 +858,10 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
             background: "rgba(255,255,255,0.15)",
             border: "none",
             color: "#fff",
-            fontSize: 16,
+            fontSize: compact ? 14 : 16,
             cursor: "pointer",
-            width: 32,
-            height: 32,
+            width: compact ? 26 : 32,
+            height: compact ? 26 : 32,
             borderRadius: "50%",
             display: "flex",
             alignItems: "center",
@@ -811,9 +881,9 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
 
         <span
           style={{
-            fontSize: 11,
+            fontSize: compact ? 10 : 11,
             color: "rgba(255,255,255,0.85)",
-            minWidth: 72,
+            minWidth: compact ? 58 : 72,
             fontVariantNumeric: "tabular-nums",
             letterSpacing: 0.2,
           }}

apps/web/src/pages/generate/components/GenerateResultPanel.tsx

@@ -1,96 +0,0 @@
-import React from "react"
-import { Typography } from "antd"
-import { PlayCircleOutlined, CloseCircleOutlined } from "@ant-design/icons"
-import type { GeneratedVideo } from "@/api/template-editor"
-import { ProgressIndicator } from "./result-panel/ProgressIndicator"
-import { ResultVideoCard } from "./result-panel/ResultVideoCard"
-
-const { Text } = Typography
-
-interface GenerateResultPanelProps {
-  generated: boolean
-  generating: boolean
-  progress: number
-  generateError: string | null
-  generatedVideos: GeneratedVideo[]
-  onVideoPreview: (video: GeneratedVideo) => void
-  onDownload: () => void
-  onShare: () => void
-  onGoToLibrary: () => void
-}
-
-const GenerateResultPanel: React.FC<GenerateResultPanelProps> = ({
-  generated,
-  generating,
-  progress,
-  generateError,
-  generatedVideos,
-  onVideoPreview,
-  onDownload,
-  onShare,
-  onGoToLibrary,
-}) => {
-  return (
-    <div className="xx-generate-result">
-      <div className="xx-result-header">
-        <h3>生成结果</h3>
-        {generated && generatedVideos.length > 0 && (
-          <span className="xx-result-count">{generatedVideos.length} 个视频</span>
-        )}
-      </div>
-
-      {generating && <ProgressIndicator progress={progress} />}
-
-      {generateError && !generating && (
-        <div className="xx-result-empty">
-          <CloseCircleOutlined style={{ fontSize: 40, color: "#ff4d4f", marginBottom: 12 }} />
-          <Text strong style={{ display: "block", marginBottom: 4 }}>
-            生成失败
-          </Text>
-          <Text style={{ fontSize: 12, color: "var(--text-secondary)" }}>
-            {typeof generateError === "string" ? generateError : "请重试"}
-          </Text>
-        </div>
-      )}
-
-      {!generated && !generating && !generateError && (
-        <div className="xx-result-empty">
-          <PlayCircleOutlined
-            style={{ fontSize: 48, color: "var(--text-tertiary)", marginBottom: 12 }}
-          />
-          <Text style={{ color: "var(--text-secondary)", fontSize: 13 }}>
-            完成配置后点击「确认生成」
-          </Text>
-          <Text style={{ color: "var(--text-tertiary)", fontSize: 12, marginTop: 4 }}>
-            生成的视频将在这里展示
-          </Text>
-        </div>
-      )}
-
-      {generated && generatedVideos.length > 0 && (
-        <div className="xx-video-grid">
-          {generatedVideos.map((video, idx) => (
-            <ResultVideoCard
-              key={video.id || idx}
-              video={video}
-              index={idx}
-              onPreview={onVideoPreview}
-              onDownload={onDownload}
-              onShare={onShare}
-            />
-          ))}
-        </div>
-      )}
-
-      {generated && (
-        <div className="xx-result-footer">
-          <button className="xx-btn xx-btn-ghost xx-btn-block" onClick={onGoToLibrary}>
-            前往成片库 →
-          </button>
-        </div>
-      )}
-    </div>
-  )
-}
-
-export default GenerateResultPanel

apps/web/src/pages/generate/components/PreviewVideoPanel.tsx

@@ -1,380 +0,0 @@
-/**
- * 右侧预览视频面板 — 服务器渲染预览架构
- *
- * Step4+: 显示预览面板
- * Step5: 播放服务器渲染的真实视频（POST /generation/preview）
- *
- * 架构：
- * - 进入 Step4/5 时自动创建服务器预览渲染任务
- * - 轮询完成后用 <video> 标签播放返回的 video_url
- * - 标题样式编辑时 CSS TitleOverlay 实时叠加预览
- * - 素材/配音/BGM 变更自动重新渲染
- * - 标题文字/样式变更标记 stale，保留旧视频 + 显示"重新预览"按钮
- *
- * 点"确认生成"时走 confirm 路径，成品就是预览视频本身，100% 一致。
- */
-import React, { useMemo, useRef, useState, useEffect } from "react"
-import { LoadingOutlined, ReloadOutlined, ExclamationCircleOutlined } from "@ant-design/icons"
-import { Button } from "antd"
-import type { TitleSettings } from "../types"
-import { getFontFamily } from "../constants"
-import type { ServerPreviewStatus } from "../hooks/useServerPreview"
-
-interface PreviewVideoPanelProps {
-  /** 服务器预览状态 */
-  previewStatus: ServerPreviewStatus
-  /** 服务器渲染视频 URL */
-  videoUrl: string | null
-  /** 渲染进度 0-100 */
-  progress: number
-  /** 错误信息 */
-  error: string | null
-  /** 重新预览回调 */
-  onRetry: () => void
-  /** 视频比例 */
-  videoRatio: string
-  /** 标题设置 — CSS 实时预览层 */
-  titleSettings?: TitleSettings
-  /** 素材数量 */
-  assetCount?: number
-}
-
-/* ── ASS 坐标系参数（与后端 ass_subtitle_builder.py 一致） ── */
-const TITLE_MARGIN_TOP = 120
-const TITLE_MARGIN_BOTTOM = 60
-const TITLE_MARGIN_SIDE = 40
-
-/** 根据视频比例返回后端实际渲染分辨率（PlayResX × PlayResY） */
-function getResolution(ratio: string): { width: number; height: number } {
-  switch (ratio) {
-    case "16:9":
-      return { width: 1920, height: 1080 }
-    case "1:1":
-      return { width: 1080, height: 1080 }
-    case "9:16":
-    default:
-      return { width: 1080, height: 1920 }
-  }
-}
-
-function getPositionStyle(
-  position: string,
-  playResX: number,
-  playResY: number,
-): React.CSSProperties {
-  const sidePercent = (TITLE_MARGIN_SIDE / playResX) * 100
-  switch (position) {
-    case "bottom":
-      return {
-        bottom: `${(TITLE_MARGIN_BOTTOM / playResY) * 100}%`,
-        left: `${sidePercent}%`,
-        right: `${sidePercent}%`,
-        textAlign: "center",
-      }
-    case "center":
-      return {
-        top: "50%",
-        transform: "translateY(-50%)",
-        left: `${sidePercent}%`,
-        right: `${sidePercent}%`,
-        textAlign: "center",
-      }
-    case "top":
-    default:
-      return {
-        top: `${(TITLE_MARGIN_TOP / playResY) * 100}%`,
-        left: `${sidePercent}%`,
-        right: `${sidePercent}%`,
-        textAlign: "center",
-      }
-  }
-}
-
-function buildTitleStyle(
-  settings: TitleSettings,
-  containerHeight: number,
-  playResY: number,
-): React.CSSProperties {
-  // 字号按容器高度与 PlayResY 的比例缩放，不设上限（与后端一致）
-  const fontSizePx =
-    containerHeight > 0
-      ? (settings.size / playResY) * containerHeight
-      : (settings.size / playResY) * 400
-
-  const base: React.CSSProperties = {
-    fontFamily: getFontFamily(settings.font),
-    fontSize: `${fontSizePx}px`,
-    color: settings.color || "#ffffff",
-    fontWeight: settings.bold ? 700 : 400,
-    fontStyle: settings.italic ? "italic" : "normal",
-    lineHeight: 1.05,
-    wordBreak: "break-word",
-    pointerEvents: "none",
-    userSelect: "none",
-  }
-  if (settings.stroke) base.WebkitTextStroke = "1px #000000"
-  if (settings.shadow) base.textShadow = "2px 2px 4px rgba(0,0,0,0.8)"
-  return base
-}
-
-/** CSS 标题实时预览覆盖层 */
-const TitleOverlay: React.FC<{ titleSettings: TitleSettings; videoRatio: string }> = ({
-  titleSettings,
-  videoRatio,
-}) => {
-  const containerRef = useRef<HTMLDivElement>(null)
-  const [containerHeight, setContainerHeight] = useState(400)
-
-  useEffect(() => {
-    const el = containerRef.current
-    if (!el) return
-    const ro = new ResizeObserver((entries) => {
-      for (const entry of entries) {
-        const h = entry.contentRect.height
-        if (h > 0) setContainerHeight(h)
-      }
-    })
-    ro.observe(el)
-    const rect = el.getBoundingClientRect()
-    if (rect.height > 0) setContainerHeight(rect.height)
-    return () => ro.disconnect()
-  }, [])
-
-  const { width: playResX, height: playResY } = getResolution(videoRatio)
-
-  const positionStyle = useMemo(
-    () => getPositionStyle(titleSettings.position, playResX, playResY),
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-    [titleSettings.position, playResX, playResY],
-  )
-  const titleStyle = useMemo(
-    () => buildTitleStyle(titleSettings, containerHeight, playResY),
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-    [
-      containerHeight,
-      titleSettings.font,
-      titleSettings.size,
-      titleSettings.color,
-      titleSettings.bold,
-      titleSettings.italic,
-      titleSettings.stroke,
-      titleSettings.shadow,
-      playResY,
-    ],
-  )
-
-  const displayTitle = titleSettings.title?.trim() || "标题预览"
-
-  return (
-    <div
-      ref={containerRef}
-      style={{
-        position: "absolute",
-        inset: 0,
-        zIndex: 20,
-        pointerEvents: "none",
-        overflow: "hidden",
-      }}
-    >
-      <div style={{ ...positionStyle, ...titleStyle, position: "absolute" }}>
-        {displayTitle.split(/[/／]/).map((part, i) => (
-          <span key={i}>
-            {i > 0 && <br />}
-            {part}
-          </span>
-        ))}
-      </div>
-    </div>
-  )
-}
-
-/* ── 主组件 ── */
-
-export const PreviewVideoPanel: React.FC<PreviewVideoPanelProps> = ({
-  previewStatus,
-  videoUrl,
-  progress,
-  error,
-  onRetry,
-  videoRatio,
-  titleSettings,
-  assetCount,
-}) => {
-  const videoAspectStyle = { aspectRatio: (videoRatio || "9:16").replace(":", "/") }
-  const isLoading = previewStatus === "loading"
-  const isReady = previewStatus === "ready" || previewStatus === "stale"
-  const isFailed = previewStatus === "failed"
-  const isIdle = previewStatus === "idle"
-  const isStale = previewStatus === "stale"
-
-  return (
-    <div className="xx-generate-preview">
-      <div className="xx-preview-header">
-        <h3>预览视频</h3>
-        {isReady && !isStale && <span className="xx-preview-badge">服务器渲染</span>}
-        {isStale && (
-          <span
-            style={{
-              fontSize: 12,
-              color: "#faad14",
-              display: "flex",
-              alignItems: "center",
-              gap: 4,
-            }}
-          >
-            <ExclamationCircleOutlined /> 配置已变更
-          </span>
-        )}
-        {isLoading && <span className="xx-preview-badge">渲染中</span>}
-      </div>
-
-      <div className="xx-preview-video" style={{ ...videoAspectStyle, position: "relative" }}>
-        {/* 加载中 */}
-        {isLoading && (
-          <div
-            style={{
-              position: "absolute",
-              inset: 0,
-              display: "flex",
-              flexDirection: "column",
-              alignItems: "center",
-              justifyContent: "center",
-              zIndex: 5,
-              background: "rgba(0,0,0,0.6)",
-            }}
-          >
-            <LoadingOutlined style={{ fontSize: 36, color: "#fff" }} spin />
-            <p style={{ marginTop: 12, color: "rgba(255,255,255,0.9)", fontSize: 14 }}>
-              正在渲染预览视频{progress > 0 ? `...${progress}%` : "..."}
-            </p>
-            <p style={{ marginTop: 4, color: "rgba(255,255,255,0.5)", fontSize: 12 }}>
-              首次渲染约需 30-60 秒
-            </p>
-          </div>
-        )}
-
-        {/* 空闲状态（尚未触发预览） */}
-        {isIdle && (
-          <div
-            style={{
-              position: "absolute",
-              inset: 0,
-              display: "flex",
-              flexDirection: "column",
-              alignItems: "center",
-              justifyContent: "center",
-              background: "rgba(0,0,0,0.3)",
-              zIndex: 5,
-            }}
-          >
-            <p style={{ color: "rgba(255,255,255,0.7)", fontSize: 14 }}>等待素材选择...</p>
-          </div>
-        )}
-
-        {/* 服务器渲染的真实视频 */}
-        {isReady && videoUrl && (
-          <video
-            key={videoUrl}
-            src={videoUrl}
-            controls
-            autoPlay
-            loop
-            playsInline
-            style={{
-              width: "100%",
-              height: "100%",
-              objectFit: "contain",
-              position: "absolute",
-              inset: 0,
-              zIndex: 1,
-            }}
-          />
-        )}
-
-        {/* 标题样式实时预览层（仅在有视频时叠加） */}
-        {isReady && titleSettings && (
-          <TitleOverlay titleSettings={titleSettings} videoRatio={videoRatio} />
-        )}
-
-        {/* stale 遮罩：配置变更提示 */}
-        {isStale && (
-          <div
-            style={{
-              position: "absolute",
-              bottom: 0,
-              left: 0,
-              right: 0,
-              padding: "10px 16px",
-              background: "linear-gradient(transparent, rgba(0,0,0,0.85))",
-              display: "flex",
-              alignItems: "center",
-              justifyContent: "space-between",
-              gap: 8,
-              zIndex: 30,
-            }}
-          >
-            <span style={{ color: "rgba(255,255,255,0.9)", fontSize: 12 }}>
-              配置已变更，预览内容可能不是最新
-            </span>
-            <Button size="small" type="primary" icon={<ReloadOutlined />} onClick={onRetry}>
-              重新预览
-            </Button>
-          </div>
-        )}
-
-        {/* 错误状态 */}
-        {isFailed && (
-          <div
-            style={{
-              position: "absolute",
-              inset: 0,
-              display: "flex",
-              flexDirection: "column",
-              alignItems: "center",
-              justifyContent: "center",
-              background: "rgba(0,0,0,0.7)",
-              zIndex: 10,
-              padding: 24,
-            }}
-          >
-            <ExclamationCircleOutlined style={{ fontSize: 40, color: "#ff4d4f" }} />
-            <p
-              style={{
-                marginTop: 12,
-                color: "rgba(255,255,255,0.9)",
-                fontSize: 14,
-                textAlign: "center",
-              }}
-            >
-              {error || "预览渲染失败"}
-            </p>
-            <Button
-              type="primary"
-              icon={<ReloadOutlined />}
-              onClick={onRetry}
-              style={{ marginTop: 12 }}
-            >
-              重新预览
-            </Button>
-          </div>
-        )}
-      </div>
-
-      {/* 素材信息 */}
-      {assetCount !== undefined && assetCount > 0 && (
-        <div className="xx-preview-info">
-          <div className="xx-preview-info-row">
-            <span>素材数</span>
-            <span>{assetCount} 个</span>
-          </div>
-          <div className="xx-preview-info-row">
-            <span>比例</span>
-            <span>{videoRatio}</span>
-          </div>
-        </div>
-      )}
-    </div>
-  )
-}
-
-export default PreviewVideoPanel

apps/web/src/pages/generate/components/Step5VoiceSelect.tsx

@@ -37,6 +37,12 @@ const isAiVoice = (item: AssetItem): boolean => {
   return (!duration || duration <= 0) && (!size || size <= 0)
 }
 
+/** 格式化时长（秒 → "14.7秒"；0/无效 → "时长未知"，不做任何时长过滤） */
+const formatDurationSeconds = (seconds?: number): string => {
+  if (!seconds || seconds <= 0) return "时长未知"
+  return `${seconds.toFixed(1)}秒`
+}
+
 /** 格式化文件大小 */
 const formatFileSize = (bytes?: number): string => {
   if (!bytes || bytes <= 0) return "未知"
@@ -261,7 +267,9 @@ const Step5VoiceSelect: React.FC<Step5VoiceSelectProps> = ({
               >
                 {isAiVoice(item) ? (
                   <span style={{ color: "#1677ff", fontWeight: 500 }}>AI 音色</span>
-                ) : null}
+                ) : (
+                  <span>{formatDurationSeconds(getDuration(item))}</span>
+                )}
                 <span>{isAiVoice(item) ? "按文本合成" : formatFileSize(getFileSize(item))}</span>
               </div>
             </div>

apps/web/src/pages/generate/components/Step6CoverSettings.tsx

@@ -91,11 +91,13 @@ const Step6CoverSettings: React.FC<Step6CoverSettingsProps> = (props) => {
       shadow: props.titleSettings?.shadow ?? false,
     },
     covers: batchCoversList,
-    onCoversChange: (urls) => {
-      // 按卡片顺序写回对应变体索引
+    onCoversChange: (updater) => {
+      // 按卡片顺序写回对应变体索引；支持函数式 updater（#1750：串行回写避免闭包覆盖）
+      const prevCardView = cardIndexes.map((vi) => (props.previewCovers || [])[vi] || "")
+      const nextCardView = typeof updater === "function" ? updater(prevCardView) : updater
       const next = [...(props.previewCovers || [])]
       cardIndexes.forEach((vi, cardPos) => {
-        next[vi] = urls[cardPos] || ""
+        next[vi] = nextCardView[cardPos] || ""
       })
       props.onPreviewCoversChange?.(next)
     },
@@ -142,7 +144,8 @@ const Step6CoverSettings: React.FC<Step6CoverSettingsProps> = (props) => {
           <Button
             buttonType="primary"
             onClick={() => void batchCovers.generateAll()}
-            disabled={completedVideos.length === 0 || batchCovers.loadingIndex !== null}
+            disabled={completedVideos.length === 0 || batchCovers.busyIndexes.length > 0}
+            style={{ whiteSpace: "nowrap", flexShrink: 0 }}
           >
             ✨ 一键全部自动生成
           </Button>
@@ -151,8 +154,8 @@ const Step6CoverSettings: React.FC<Step6CoverSettingsProps> = (props) => {
         <div className="xx-cover-grid">
           {cardIndexes.map((variantIndex, cardPos) => {
             const url = batchCoversList[cardPos]
-            const isLoading = batchCovers.loadingIndex === cardPos
-            const isUploading = batchCovers.uploadingIndex === cardPos
+            const isLoading = batchCovers.busyIndexes.includes(cardPos)
+            const isUploading = batchCovers.uploadingIndexes.includes(cardPos)
             const title = batchTitles[cardPos]
             return (
               <div className="xx-cover-card" key={variantIndex}>

apps/web/src/pages/generate/components/result-panel/ProgressIndicator.tsx

@@ -1,40 +0,0 @@
-import React from "react"
-import { Typography } from "antd"
-
-const { Text } = Typography
-
-interface ProgressIndicatorProps {
-  progress: number
-}
-
-export const ProgressIndicator: React.FC<ProgressIndicatorProps> = ({ progress }) => {
-  return (
-    <div className="xx-result-progress">
-      <div className="xx-progress-circle">
-        <svg viewBox="0 0 80 80">
-          <circle cx="40" cy="40" r="36" fill="none" stroke="var(--border-color)" strokeWidth="6" />
-          <circle
-            cx="40"
-            cy="40"
-            r="36"
-            fill="none"
-            stroke="var(--primary-color)"
-            strokeWidth="6"
-            strokeDasharray={`${Math.round(progress) * 2.26} 226`}
-            strokeLinecap="round"
-            transform="rotate(-90 40 40)"
-          />
-        </svg>
-        <span className="xx-progress-percent">{Math.round(progress)}%</span>
-      </div>
-      <div className="xx-progress-text">
-        <Text strong style={{ fontSize: 14, display: "block", marginBottom: 4 }}>
-          正在生成视频
-        </Text>
-        <Text style={{ fontSize: 12, color: "var(--text-secondary)" }}>
-          AI 正在处理素材，请稍候…
-        </Text>
-      </div>
-    </div>
-  )
-}

apps/web/src/pages/generate/components/result-panel/ResultVideoCard.tsx

@@ -1,63 +0,0 @@
-import React from "react"
-import { PlayCircleOutlined, DownloadOutlined, ShareAltOutlined } from "@ant-design/icons"
-import type { GeneratedVideo } from "@/api/template-editor"
-import { formatDuration } from "@/api/voice-clone"
-
-interface ResultVideoCardProps {
-  video: GeneratedVideo
-  index: number
-  onPreview: (video: GeneratedVideo) => void
-  onDownload: () => void
-  onShare: () => void
-}
-
-export const ResultVideoCard: React.FC<ResultVideoCardProps> = ({
-  video,
-  index,
-  onPreview,
-  onDownload,
-  onShare,
-}) => {
-  return (
-    <div className="xx-video-card" onClick={() => onPreview(video)}>
-      <div className="xx-video-thumb">
-        {video.thumbnail_url ? (
-          <img src={video.thumbnail_url} alt="" />
-        ) : (
-          <div className="xx-video-thumb-placeholder">
-            <PlayCircleOutlined style={{ fontSize: 32, opacity: 0.5 }} />
-          </div>
-        )}
-        <div className="xx-video-play-overlay">
-          <PlayCircleOutlined style={{ fontSize: 36, color: "#fff" }} />
-        </div>
-        {video.duration && (
-          <span className="xx-video-duration">{formatDuration(video.duration)}</span>
-        )}
-      </div>
-      <div className="xx-video-info">
-        <div className="xx-video-title">视频 {index + 1}</div>
-        <div className="xx-video-actions">
-          <button
-            className="xx-video-action-btn"
-            onClick={(e) => {
-              e.stopPropagation()
-              onDownload()
-            }}
-          >
-            <DownloadOutlined />
-          </button>
-          <button
-            className="xx-video-action-btn"
-            onClick={(e) => {
-              e.stopPropagation()
-              onShare()
-            }}
-          >
-            <ShareAltOutlined />
-          </button>
-        </div>
-      </div>
-    </div>
-  )
-}

apps/web/src/pages/generate/generate.css

@@ -3282,17 +3282,28 @@
 /* ============================================================
    批量前端 Canvas 预览网格（Issue #1677 修正：纯前端实时预览）
    ============================================================ */
+/* #1741：卡片整体缩小至约 3/5——宽屏排 3 列（卡片限宽 220px 居中），
+   中屏自动回退 2 列，窄屏 1 列（见下方媒体查询）；卡片保持 9:16 比例不变形 */
 .xx-canvas-grid {
   display: grid;
-  grid-template-columns: repeat(2, 1fr);
-  gap: 16px;
+  grid-template-columns: repeat(auto-fill, minmax(160px, 180px));
+  justify-content: center;
+  gap: 14px;
+}
+
+/* 窄屏单列时卡片限宽居中，避免 1fr 拉伸导致卡片过高 */
+@media (max-width: 960px) {
+  .xx-canvas-grid {
+    grid-template-columns: minmax(0, 320px);
+  }
 }
 
 .xx-canvas-grid-card {
+  position: relative;
   border: 2px solid var(--border-primary, #e2e8f0);
   border-radius: 12px;
   overflow: hidden;
-  background: #000;
+  background: transparent;
   transition: border-color 0.2s ease;
   min-width: 0;
 }
@@ -3330,6 +3341,37 @@
   accent-color: var(--primary-color, #1677ff);
 }
 
+/* #1750：批量变体片段加载/错误占位（9:16 竖屏比例，与播放器卡片同尺寸防塌陷） */
+.xx-variant-clips-status {
+  position: relative;
+  width: 100%;
+  aspect-ratio: 9 / 16;
+  max-height: 70vh;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: 4px;
+  font-size: 13px;
+  color: rgba(255, 255, 255, 0.75);
+  background: #0a0a0a;
+  border-radius: 16px;
+  overflow: hidden;
+  box-shadow:
+    0 4px 6px -1px rgba(0, 0, 0, 0.3),
+    0 20px 50px -12px rgba(0, 0, 0, 0.5),
+    inset 0 0 0 1px rgba(255, 255, 255, 0.06);
+}
+
+.xx-variant-clips-status .anticon {
+  font-size: 22px;
+}
+
+.xx-variant-clips-error-text {
+  color: rgba(255, 255, 255, 0.85);
+  font-size: 13px;
+}
+
 /* ============================================================
    批量标题：AI 一键生成行（Issue #1677）
    ============================================================ */
@@ -3361,16 +3403,18 @@
    第5步确认生成：批量渲染进度网格（Issue #1677）
    ============================================================ */
 .xx-batch-gen-grid {
+  justify-items: center;
   display: grid;
-  grid-template-columns: repeat(2, 1fr);
-  gap: 16px;
+  grid-template-columns: repeat(auto-fill, minmax(160px, 180px));
+  justify-content: center;
+  gap: 14px;
 }
 
 .xx-batch-gen-card {
   border: 1px solid var(--border-primary, #e2e8f0);
   border-radius: 12px;
   padding: 14px;
-  background: var(--bg-surface, #fff);
+  background: transparent;
   display: flex;
   flex-direction: column;
   gap: 10px;
@@ -3435,10 +3479,10 @@
   word-break: break-word;
 }
 
-/* ── 响应式：窄屏批量网格回退单列 ── */
+/* ── 响应式：窄屏批量网格回退单列（.xx-canvas-grid 的窄屏限宽见网格定义处 #1741） ── */
 @media (max-width: 960px) {
-  .xx-canvas-grid,
   .xx-batch-gen-grid {
-    grid-template-columns: 1fr;
+    justify-items: center;
+    grid-template-columns: minmax(0, 320px);
   }
 }

apps/web/src/pages/generate/hooks/generate-video/types.ts

@@ -42,6 +42,12 @@ export interface UseGenerateVideoProps {
   variantCoverUrls?: string[]
   /** 勾选要生成的变体索引（批量模式） */
   selectedVariantIndexes?: number[]
+  /**
+   * 批量变体剪辑计划 ID（#1744，按变体全量索引长度=previewCount）：
+   * 预览阶段后端独立选片产出，正式生成按勾选顺序回传，实现预览即成片；
+   * 为空（降级本地模拟/后端未上线）时不传，后端自行独立选片。
+   */
+  variantPlanIds?: string[]
 }
 
 /** 生成阶段 */

apps/web/src/pages/generate/hooks/step2-materials/useSmartMatch.ts

@@ -13,21 +13,22 @@ interface UseSmartMatchOptions {
 }
 
 /** 默认 limit（拿不到目标时长时的兜底上限） */
-const DEFAULT_LIMIT = 10
-/** 每个素材切片按 15 秒估算所需素材数 */
-const SECONDS_PER_ASSET = 15
+const DEFAULT_LIMIT = 30
+/**
+ * 候选池放大倍数（#1744）：批量 N 个变体独立选片、跨变体 20% 区间避让需要
+ * 足够大的素材池才能保证 N 条成片素材排布互不相同（历史已用区间写回素材 metadata）。
+ * 旧规则「总时长/15 秒」只够 1 条成片的选片量，池太小会导致变体间大量复用同区间。
+ */
+const ASSET_POOL_MULTIPLIER = 3
 
 /**
- * 根据模板 segments 计算所需素材数量上限。
- * 取每个 segment 的 duration_min 之和作为目标视频总时长，
- * 再按 15 秒/素材估算需要多少个素材，且保证不少于片段数（每个片段至少 1 个素材）；
- * 结果钳制到 [1, 200] 区间（后端 limit 上限 200）。
+ * 根据模板 segments 计算智能匹配候选素材数量上限（#1750：模板无时长概念）。
+ * 候选池 = 片段数 × 3：每个片段至少 3 个候选素材供变体间洗牌/避让
+ * （独立选片 + 区间不重叠）；结果钳制到 [1, 200] 区间（后端 limit 上限 200）。
  */
-function computeLimitFromSegments(segments?: TemplateSegment[]): number {
+export function computeLimitFromSegments(segments?: TemplateSegment[]): number {
   if (!segments || segments.length === 0) return DEFAULT_LIMIT
-  const totalSeconds = segments.reduce((sum, seg) => sum + (seg.duration_min || 0), 0)
-  if (totalSeconds <= 0) return DEFAULT_LIMIT
-  const limit = Math.max(segments.length, Math.ceil(totalSeconds / SECONDS_PER_ASSET))
+  const limit = segments.length * ASSET_POOL_MULTIPLIER
   return Math.max(1, Math.min(limit, 200))
 }
 

apps/web/src/pages/generate/hooks/useBatchCovers.ts

@@ -1,6 +1,13 @@
 /**
- * 批量封面 Hook（Issue #1677）
+ * 批量封面 Hook（Issue #1677 / #1750 修复）
  * N 个视频时：逐个自动生成封面（从对应成片抽帧 + 叠加对应标题）或上传自定义封面
+ *
+ * #1750 修复：
+ * - patchCover 改为函数式 updater 回写（onCoversChange 支持 (prev)=>next），
+ *   修复串行 generateAll 时闭包捕获旧 covers 数组导致回写互相覆盖的 bug；
+ * - loading/uploading 状态改数组（busyIndexes/uploadingIndexes），支持多个卡片在途；
+ * - generateOne 返回 boolean，generateAll 据此统计成功/失败数量分级提示，单个失败不阻塞；
+ * - generateAll 一次点击即处理所有未生成封面（无需点 3 次）。
  */
 import { useCallback, useState } from "react"
 import { message } from "antd"
@@ -8,6 +15,9 @@ import { generateCover } from "@/api/generation"
 import { uploadAssetDirect, getAssetLibraries } from "@/api/assets"
 import type { GeneratedVideo } from "@/api/template-editor"
 
+/** onCoversChange 支持直接传值或函数式 updater（函数式用于串行回写避免闭包覆盖） */
+type CoversChangeFn = (updater: string[] | ((prev: string[]) => string[])) => void
+
 interface UseBatchCoversOptions {
   selectedTemplate: string
   generatedVideos: GeneratedVideo[]
@@ -24,7 +34,7 @@ interface UseBatchCoversOptions {
     shadow: boolean
   }
   covers: string[]
-  onCoversChange: (urls: string[]) => void
+  onCoversChange: CoversChangeFn
 }
 
 export function useBatchCovers({
@@ -35,28 +45,46 @@ export function useBatchCovers({
   covers,
   onCoversChange,
 }: UseBatchCoversOptions) {
-  const [loadingIndex, setLoadingIndex] = useState<number | null>(null)
-  const [uploadingIndex, setUploadingIndex] = useState<number | null>(null)
+  /** 正在自动生成封面的变体序号集合（数组支持多个卡片同时在途） */
+  const [busyIndexes, setBusyIndexes] = useState<number[]>([])
+  /** 正在上传自定义封面的变体序号集合 */
+  const [uploadingIndexes, setUploadingIndexes] = useState<number[]>([])
 
+  const addBusy = useCallback((i: number) => {
+    setBusyIndexes((prev) => (prev.includes(i) ? prev : [...prev, i]))
+  }, [])
+  const removeBusy = useCallback((i: number) => {
+    setBusyIndexes((prev) => prev.filter((x) => x !== i))
+  }, [])
+  const addUploading = useCallback((i: number) => {
+    setUploadingIndexes((prev) => (prev.includes(i) ? prev : [...prev, i]))
+  }, [])
+  const removeUploading = useCallback((i: number) => {
+    setUploadingIndexes((prev) => prev.filter((x) => x !== i))
+  }, [])
+
+  /** 函数式回写单个封面位置（基于最新 prev，不受闭包旧值影响） */
   const patchCover = useCallback(
     (index: number, url: string) => {
-      const next = [...covers]
-      next[index] = url
-      onCoversChange(next)
+      onCoversChange((prev) => {
+        const next = [...prev]
+        next[index] = url
+        return next
+      })
     },
-    [covers, onCoversChange],
+    [onCoversChange],
   )
 
-  /** 为第 index 个视频自动生成封面 */
+  /** 为第 index 个视频自动生成封面；返回是否成功（供 generateAll 统计） */
   const generateOne = useCallback(
-    async (index: number) => {
+    async (index: number): Promise<boolean> => {
       const finalVideos = generatedVideos.filter((v) => v.status === "completed")
       const target = finalVideos[index] || generatedVideos[index]
       if (!target) {
         message.warning("该视频尚未生成完成")
-        return
+        return false
       }
-      setLoadingIndex(index)
+      addBusy(index)
       try {
         const titleText = titles[index] || ""
         const response = await generateCover(selectedTemplate, {
@@ -82,23 +110,25 @@ export function useBatchCovers({
         if (url) {
           patchCover(index, url)
           message.success(`视频 ${index + 1} 封面生成成功`)
-        } else {
-          message.warning(`视频 ${index + 1} 封面生成未返回图片，请重试`)
+          return true
         }
+        message.warning(`视频 ${index + 1} 封面生成未返回图片，请重试`)
+        return false
       } catch (err) {
         console.error(`[封面] 视频 ${index + 1} 生成失败:`, err)
         message.error(`视频 ${index + 1} 封面生成失败，请重试`)
+        return false
       } finally {
-        setLoadingIndex(null)
+        removeBusy(index)
       }
     },
-    [generatedVideos, titles, titleStyle, selectedTemplate, patchCover],
+    [generatedVideos, titles, titleStyle, selectedTemplate, patchCover, addBusy, removeBusy],
   )
 
   /** 为第 index 个视频上传自定义封面 */
   const uploadOne = useCallback(
     async (index: number, file: File) => {
-      setUploadingIndex(index)
+      addUploading(index)
       try {
         const libs = await getAssetLibraries()
         const imageLib = libs.find((l) => l.kind === "image") || libs[0]
@@ -121,26 +151,43 @@ export function useBatchCovers({
         console.error(`[封面] 视频 ${index + 1} 上传失败:`, err)
         message.error("封面上传失败，请重试")
       } finally {
-        setUploadingIndex(null)
+        removeUploading(index)
       }
     },
-    [patchCover],
+    [patchCover, addUploading, removeUploading],
   )
 
-  /** 一键全部自动生成（串行，避免队列限流） */
+  /** 一键全部自动生成（串行，避免队列限流；单个失败不阻塞，结束后分级提示） */
   const generateAll = useCallback(async () => {
     const finalVideos = generatedVideos.filter((v) => v.status === "completed")
-    for (let i = 0; i < finalVideos.length; i++) {
-      if (covers[i]) continue // 已有封面跳过
+    const total = finalVideos.length
+    // 待处理：基于调用时刻的 covers 快照判断（已有封面跳过）；
+    // 回写走函数式 updater，循环内不再依赖可能过期的 covers 闭包
+    const pending = finalVideos.map((_, i) => i).filter((i) => !covers[i])
+    if (pending.length === 0) {
+      message.info("所有视频封面已生成")
+      return
+    }
+    let okCount = 0
+    let failCount = 0
+    for (const i of pending) {
       // eslint-disable-next-line no-await-in-loop
-      await generateOne(i)
+      const ok = await generateOne(i)
+      if (ok) okCount += 1
+      else failCount += 1
+    }
+    if (failCount === 0) {
+      message.success(`全部 ${total} 个封面已生成`)
+    } else if (okCount === 0) {
+      message.error("封面生成全部失败，请重试")
+    } else {
+      message.warning(`已生成 ${okCount} 个封面，${failCount} 个失败，请对失败项重试`)
     }
-    message.success("全部封面已生成")
   }, [generatedVideos, covers, generateOne])
 
   return {
-    loadingIndex,
-    uploadingIndex,
+    busyIndexes,
+    uploadingIndexes,
     generateOne,
     uploadOne,
     generateAll,

apps/web/src/pages/generate/hooks/useBatchVariantPlans.ts

@@ -0,0 +1,153 @@
+/**
+ * 批量变体真实片段 Hook（#1744 接入 / #1750 修正）
+ *
+ * 批量预览（N>1）进入第 4 步时，向后端轻量接口 POST /generation/variant-plans
+ * 申请 N 个变体的独立剪辑计划片段：
+ * - 接口只做选片/建 plan（秒级），不渲染视频，无渲染成本；
+ * - 选片逻辑与正式批量生成（POST /generation/tasks?count=N）完全同源
+ *   （reselect_plan_for_variant：素材洗牌 + main 片段洗牌 + 起点随机 +
+ *   跨变体 20% 区间避让 + 使用区间写回素材 metadata），
+ *   因此前端按这些 clips 播放的预览与最终成片一致；
+ * - 正式生成时把 plan_ids 回传，后端直接关联预览 plan 渲染，不再重新选片。
+ *
+ * 错误处理（#1750 基线：严禁用前端假数据冒充预览）：
+ * - 端点 404（后端未上线）/ 400 / 网络错误 / 超时：一律置 error 状态，
+ *   UI 显示「预览加载失败，请重试」，不再静默降级本地模拟；
+ * - 单个变体 clips 为空同样视为加载失败（计划数据不完整）。
+ *
+ * N=1 不调用本 hook（单视频零回归）。
+ */
+import { useCallback, useEffect, useRef, useState } from "react"
+import type { EditPlanClip } from "@/api/template-editor"
+import { createBatchVariantPlans, type VariantPlan } from "@/api/generation/variantPlans"
+
+export interface BatchVariantClipsState {
+  /** 各变体的服务端真实片段（按 variant_index 排序）；未就绪为空数组 */
+  clipsByVariant: EditPlanClip[][]
+  /** 各变体的 plan_id（正式生成回传，保证预览即成片）；未就绪为空串 */
+  planIdsByVariant: string[]
+  /** 是否正在向后端申请变体计划 */
+  loading: boolean
+  /** 后端真实片段是否全部可用（每个变体都有 ≥1 条片段） */
+  ready: boolean
+  /** 加载失败（端点未上线/网络错误/数据不完整）；true 时 UI 显示错误态+重试 */
+  error: boolean
+  /** 用户点击「重试」：强制重新申请变体计划 */
+  retry: () => void
+}
+
+interface UseBatchVariantPlansOptions {
+  /** 是否启用：仅批量（count>1）且素材已选时为 true */
+  enabled: boolean
+  count: number
+  templateId: string
+  assetIds: string[]
+  /** 源剪辑计划 ID（草稿/预览关联），无则空串由后端兜底最新 plan */
+  sourcePlanId?: string
+}
+
+export function useBatchVariantPlans({
+  enabled,
+  count,
+  templateId,
+  assetIds,
+  sourcePlanId = "",
+}: UseBatchVariantPlansOptions): BatchVariantClipsState {
+  const [clipsByVariant, setClipsByVariant] = useState<EditPlanClip[][]>([])
+  const [planIdsByVariant, setPlanIdsByVariant] = useState<string[]>([])
+  const [loading, setLoading] = useState(false)
+  const [error, setError] = useState(false)
+
+  const requestSeqRef = useRef(0)
+  // 记录上次成功申请的入参指纹，素材/数量未变时不重复请求
+  const lastKeyRef = useRef("")
+  // 重试计数（state）：用户点重试时 +1，驱动 effect 重新发起请求（即使指纹相同）；
+  // 用 state 而非 ref + 直接调 load，避免 retry 与 effect 双发导致 seq 竞争
+  const [retryNonce, setRetryNonce] = useState(0)
+
+  const load = useCallback(async () => {
+    const seq = ++requestSeqRef.current
+    setLoading(true)
+    setError(false)
+    try {
+      const resp = await createBatchVariantPlans({
+        template_id: templateId,
+        asset_ids: assetIds,
+        count,
+        ...(sourcePlanId ? { source_edit_plan_id: sourcePlanId } : {}),
+      })
+      if (seq !== requestSeqRef.current) return
+
+      const items: VariantPlan[] = Array.isArray(resp.items) ? resp.items : []
+      const clips: EditPlanClip[][] = Array.from({ length: count }, () => [])
+      const planIds: string[] = Array.from({ length: count }, () => "")
+      for (const item of items) {
+        const idx = item.variant_index
+        if (idx < 0 || idx >= count) continue
+        planIds[idx] = item.plan_id || ""
+        clips[idx] = (item.clips || [])
+          .filter((c) => c && c.asset_id && c.status === "ready")
+          .sort((a, b) => a.order - b.order)
+      }
+      // 数据完整性校验：每个变体都必须有真实片段，否则视为失败（不允许假数据冒充）
+      const incomplete = clips.some((list) => list.length === 0)
+      if (incomplete) {
+        console.warn("[useBatchVariantPlans] 变体计划数据不完整（存在空片段变体），标记加载失败")
+        setClipsByVariant([])
+        setPlanIdsByVariant([])
+        setError(true)
+      } else {
+        setClipsByVariant(clips)
+        setPlanIdsByVariant(planIds)
+        setError(false)
+      }
+    } catch (err) {
+      if (seq !== requestSeqRef.current) return
+      // 404（后端端点未上线）/ 400（参数错误）/ 网络错误 / 超时：统一错误态
+      console.warn("[useBatchVariantPlans] 申请变体计划失败，预览加载失败:", err)
+      setClipsByVariant([])
+      setPlanIdsByVariant([])
+      setError(true)
+    } finally {
+      if (seq === requestSeqRef.current) setLoading(false)
+    }
+  }, [templateId, count, sourcePlanId, assetIds])
+
+  /** 用户点击「重试」：nonce +1 驱动 effect 重新发起请求（effect 内 lastKey 校验保证只发一次） */
+  const retry = useCallback(() => {
+    setRetryNonce((n) => n + 1)
+  }, [])
+
+  useEffect(() => {
+    if (!enabled || !templateId || assetIds.length === 0 || count <= 1) {
+      requestSeqRef.current += 1
+      // 函数式更新：已是目标值时返回 prev（Object.is 相等 React 跳过渲染），
+      // 避免父组件传入内联字面量数组导致 effect 每次 render 触发 → 无限 setState 循环
+      setClipsByVariant((prev) => (prev.length === 0 ? prev : []))
+      setPlanIdsByVariant((prev) => (prev.length === 0 ? prev : []))
+      setLoading((prev) => (prev === false ? prev : false))
+      setError((prev) => (prev === false ? prev : false))
+      lastKeyRef.current = ""
+      return
+    }
+    const key = `${retryNonce}|${templateId}|${count}|${sourcePlanId}|${[...assetIds]
+      .sort()
+      .join(",")}`
+    if (key === lastKeyRef.current) return
+    lastKeyRef.current = key
+    load()
+  }, [enabled, templateId, count, sourcePlanId, assetIds, load, retryNonce])
+
+  const ready = !error && !loading && clipsByVariant.every((list) => list.length > 0)
+
+  return {
+    clipsByVariant,
+    planIdsByVariant,
+    loading,
+    ready,
+    error,
+    retry,
+  }
+}
+
+export default useBatchVariantPlans

apps/web/src/pages/generate/hooks/useGenerateVideo.ts

@@ -178,6 +178,14 @@ export function useGenerateVideo(props: UseGenerateVideoProps) {
         isBatch && props.variantCoverUrls?.length
           ? indexes.map((i) => props.variantCoverUrls![i] || "")
           : []
+      // #1744 变体 plan 数组：预览阶段后端独立选片产出的 plan id，按勾选顺序回传，
+      // 后端直接关联这些 plan 渲染（不再重新选片）→ 预览所见即成片。
+      // 全部为空（降级本地模拟/后端端点未上线）时不传，后端走自身独立选片。
+      const variantPlansArr =
+        isBatch && props.variantPlanIds?.length
+          ? indexes.map((i) => props.variantPlanIds![i] || "")
+          : []
+      const hasVariantPlans = variantPlansArr.some((id) => !!id)
 
       try {
         const taskResp = await createGenerationTask({
@@ -200,6 +208,7 @@ export function useGenerateVideo(props: UseGenerateVideoProps) {
           ...(titlesArr.length ? { titles: titlesArr } : {}),
           ...(voiceArr.length ? { voice_library_ids: voiceArr } : {}),
           ...(coversArr.length ? { cover_urls: coversArr } : {}),
+          ...(hasVariantPlans ? { variant_plan_ids: variantPlansArr } : {}),
           ...(props.titleSettings?.title
             ? {
                 title_config: {

apps/web/src/pages/generate/hooks/usePreviewAssets.ts

@@ -44,6 +44,12 @@ interface UsePreviewAssetsReturn {
   ready: boolean
   /** 手动触发重新加载 */
   reload: () => void
+  /**
+   * 差集补拉（#1750）：后端变体计划 clips 可能引用不在用户已选列表中的素材
+   * （跨素材库选片/素材池扩展），发现 assets 中缺失的 asset_id 时补拉详情并合并，
+   * 保证预览播放器拿得到素材文件 URL，而不是静默丢片段。
+   */
+  ensureAssets: (ids: string[]) => Promise<void>
 }
 
 /**
@@ -91,11 +97,41 @@ export function usePreviewAssets(assetIds: string[], enabled: boolean): UsePrevi
     }
   }, [stableAssetIds, enabled])
 
+  // 补拉用独立序号：不干扰主 load 的竞态守卫
+  const ensureSeqRef = useRef(0)
+  const assetsRef = useRef<AssetItem[]>([])
+  useEffect(() => {
+    assetsRef.current = assets
+  }, [assets])
+
+  /**
+   * 差集补拉（#1750）：变体计划 clips 引用的 asset_id 不在当前素材列表时，
+   * 补拉素材详情并去重合并（不静默丢片段、不用假数据冒充）。
+   */
+  const ensureAssets = useCallback(async (ids: string[]) => {
+    const validIds = ids.filter((id): id is string => typeof id === "string" && id.length > 0)
+    if (!validIds.length) return
+    const seq = ++ensureSeqRef.current
+    const missing = Array.from(new Set(validIds)).filter(
+      (id) => !assetsRef.current.some((a) => a.id === id),
+    )
+    if (!missing.length) return
+    const fetched = await fetchAssetsByIds(missing)
+    if (seq !== ensureSeqRef.current || !fetched.length) return
+    const existing = new Set(assetsRef.current.map((a) => a.id))
+    const additions = fetched.filter((a) => !existing.has(a.id))
+    if (!additions.length) return
+    const merged = [...assetsRef.current, ...additions]
+    assetsRef.current = merged
+    setAssets(merged)
+    setReady(merged.length > 0)
+  }, [])
+
   useEffect(() => {
     load()
   }, [load])
 
-  return { assets, loading, ready, reload: load }
+  return { assets, loading, ready, reload: load, ensureAssets }
 }
 
 /**

apps/web/src/pages/generate/hooks/useSegmentScheduler.ts

@@ -15,6 +15,8 @@ export interface PlaybackSegment {
   startTime: number
   endTime: number
   order: number
+  /** #1754 兜底：配音时长≠clips 总时长时按比例调速，1.0 = 原速 */
+  playbackRate?: number
 }
 
 export interface SegmentSchedulerState {
@@ -131,6 +133,11 @@ export function useSegmentScheduler(segments: PlaybackSegment[]): SegmentSchedul
       if (Math.abs(video.currentTime - localTime) > 0.05) {
         video.currentTime = localTime
       }
+      // #1754：按比例调速（配音时长≠clips 总时长时的前端兜底）
+      const rate = seg.playbackRate || 1
+      if (Math.abs(video.playbackRate - rate) > 0.01) {
+        video.playbackRate = rate
+      }
 
       segIdxRef.current = index
       setCurrentSegmentIndex(index)
@@ -242,6 +249,12 @@ export function useSegmentScheduler(segments: PlaybackSegment[]): SegmentSchedul
       video.currentTime = seg.startTime
     }
 
+    // #1754：调速
+    const rate = seg?.playbackRate || 1
+    if (Math.abs(video.playbackRate - rate) > 0.01) {
+      video.playbackRate = rate
+    }
+
     try {
       await video.play()
       setIsPlaying(true)

apps/web/src/pages/generate/hooks/useServerPreview.ts

@@ -1,297 +0,0 @@
-/**
- * 服务器渲染预览 Hook
- *
- * 核心职责：
- * 1. 调用 POST /generation/preview 创建服务器预览渲染任务
- * 2. 轮询 GET /generation/preview/{task_id} 直到完成
- * 3. 返回服务器渲染的真实视频 URL（供 <video> 标签播放）
- * 4. 检测配置变更，标记预览失效（stale）或自动重新渲染
- * 5. 网络错误自动重试 2 次
- *
- * 状态机：
- *   idle → loading → ready → stale (config changed)
- *                   ↘ failed → idle (retry)
- */
-import { useState, useCallback, useRef, useEffect } from "react"
-import { createPreview, getPreviewStatus } from "@/api/generation/preview"
-import type { CreatePreviewRequest } from "@/api/generation/types"
-
-export type ServerPreviewStatus = "idle" | "loading" | "ready" | "stale" | "failed"
-
-interface UseServerPreviewOptions {
-  /** 是否启用预览（Step4+ 且有素材和模板时） */
-  enabled: boolean
-  /** 构建预览请求参数（每次 render 调用，获取最新配置） */
-  buildRequest: () => CreatePreviewRequest
-  /** 预览任务创建成功回调 */
-  onPreviewTaskCreated?: (taskId: string, sourceEditPlanId?: string) => void
-}
-
-interface UseServerPreviewReturn {
-  status: ServerPreviewStatus
-  videoUrl: string | null
-  error: string | null
-  /** 进度 0-100 */
-  progress: number
-  /** 手动触发预览创建（"重新预览"按钮或标题变更后手动刷新） */
-  triggerPreview: () => void
-  /** 当前预览任务 ID */
-  taskId: string | null
-}
-
-const POLL_INTERVAL = 2000
-const POLL_TIMEOUT = 120_000
-const MAX_NETWORK_RETRIES = 2
-
-/**
- * 对配置参数做指纹，用于检测配置是否变化
- */
-function buildFingerprint(req: CreatePreviewRequest): string {
-  return JSON.stringify({
-    t: req.template_id,
-    a: [...req.asset_ids].sort(),
-    d: req.duration,
-    r: req.video_ratio,
-    v: req.voice_library_id,
-    b: req.bgm_config,
-    title: req.title_config,
-  })
-}
-
-export function useServerPreview({
-  enabled,
-  buildRequest,
-  onPreviewTaskCreated,
-}: UseServerPreviewOptions): UseServerPreviewReturn {
-  const [status, setStatus] = useState<ServerPreviewStatus>("idle")
-  const [videoUrl, setVideoUrl] = useState<string | null>(null)
-  const [error, setError] = useState<string | null>(null)
-  const [progress, setProgress] = useState(0)
-  const [taskId, setTaskId] = useState<string | null>(null)
-
-  const pollTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
-  const timeoutTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
-  const requestSeqRef = useRef(0)
-  const renderedFingerprintRef = useRef<string>("")
-  const mountedRef = useRef(true)
-  const networkRetriesRef = useRef(0)
-
-  // 始终持有最新的 buildRequest 和回调
-  const buildRequestRef = useRef(buildRequest)
-  buildRequestRef.current = buildRequest
-  const onCreatedRef = useRef(onPreviewTaskCreated)
-  onCreatedRef.current = onPreviewTaskCreated
-
-  /* ── 清理 ── */
-  const clearTimers = useCallback(() => {
-    if (pollTimerRef.current) {
-      clearTimeout(pollTimerRef.current)
-      pollTimerRef.current = null
-    }
-    if (timeoutTimerRef.current) {
-      clearTimeout(timeoutTimerRef.current)
-      timeoutTimerRef.current = null
-    }
-  }, [])
-
-  useEffect(() => {
-    mountedRef.current = true
-    return () => {
-      mountedRef.current = false
-      clearTimers()
-    }
-  }, [clearTimers])
-
-  /* ── 创建预览 + 轮询 ── */
-  const createAndPoll = useCallback(
-    async (request: CreatePreviewRequest, seq: number) => {
-      setStatus("loading")
-      setProgress(0)
-      setError(null)
-      networkRetriesRef.current = 0
-
-      try {
-        const resp = await createPreview(request)
-        if (seq !== requestSeqRef.current || !mountedRef.current) return
-
-        // 兼容批量响应 {items, total}：取第一个变体
-        const firstTask = resp.items?.[0]
-        const taskId = firstTask?.task_id || ""
-        setTaskId(taskId)
-        onCreatedRef.current?.(taskId, resp.source_edit_plan_id)
-
-        let completed = false
-
-        // 超时保护
-        timeoutTimerRef.current = setTimeout(() => {
-          if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
-          completed = true
-          clearTimers()
-          setStatus("failed")
-          setError("预览渲染超时（120秒），请重试")
-        }, POLL_TIMEOUT)
-
-        const poll = async () => {
-          if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
-
-          try {
-            const st = await getPreviewStatus(taskId)
-            if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
-
-            if (st.status === "completed" && st.video_url) {
-              completed = true
-              clearTimers()
-              renderedFingerprintRef.current = buildFingerprint(request)
-              setVideoUrl(st.video_url)
-              setProgress(100)
-              setStatus("ready")
-              setError(null)
-              return
-            }
-
-            if (st.status === "failed" || st.status === "cancelled") {
-              completed = true
-              clearTimers()
-              setStatus("failed")
-              setError(
-                st.status === "cancelled"
-                  ? "预览任务已取消"
-                  : st.error_message || "预览渲染失败，请重试",
-              )
-              return
-            }
-
-            // pending / generating
-            if (typeof st.progress === "number") setProgress(st.progress)
-            pollTimerRef.current = setTimeout(poll, POLL_INTERVAL)
-          } catch (pollErr) {
-            if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
-            if (networkRetriesRef.current < MAX_NETWORK_RETRIES) {
-              networkRetriesRef.current += 1
-              console.warn(
-                `[ServerPreview] 轮询网络错误，第 ${networkRetriesRef.current} 次重试`,
-                pollErr,
-              )
-              pollTimerRef.current = setTimeout(poll, POLL_INTERVAL * 2)
-            } else {
-              completed = true
-              clearTimers()
-              setStatus("failed")
-              setError("网络错误，无法获取预览状态，请重试")
-            }
-          }
-        }
-
-        poll()
-      } catch (createErr) {
-        if (seq !== requestSeqRef.current || !mountedRef.current) return
-        console.error("[ServerPreview] 创建预览任务失败:", createErr)
-
-        const isNetworkError =
-          !!(createErr as { request?: unknown })?.request ||
-          (createErr as { code?: string })?.code === "ERR_NETWORK"
-
-        if (isNetworkError && networkRetriesRef.current < MAX_NETWORK_RETRIES) {
-          networkRetriesRef.current += 1
-          console.warn(`[ServerPreview] 创建任务网络错误，第 ${networkRetriesRef.current} 次重试`)
-          setTimeout(() => {
-            if (seq === requestSeqRef.current && mountedRef.current) {
-              createAndPoll(request, seq)
-            }
-          }, POLL_INTERVAL * 2)
-          return
-        }
-
-        const errData = (
-          createErr as { response?: { data?: { detail?: string; message?: string } } }
-        )?.response?.data
-        setStatus("failed")
-        setError(errData?.detail || errData?.message || "预览任务创建失败，请重试")
-      }
-    },
-    [clearTimers],
-  )
-
-  /* ── 手动触发预览 ── */
-  const triggerPreview = useCallback(() => {
-    if (!enabled) return
-    const request = buildRequestRef.current()
-    if (!request.template_id || request.asset_ids.length === 0) return
-
-    clearTimers()
-    const seq = ++requestSeqRef.current
-    setVideoUrl(null)
-    setTaskId(null)
-    createAndPoll(request, seq)
-  }, [enabled, clearTimers, createAndPoll])
-
-  /* ── 自动触发 + 配置变更检测 ── */
-  // 每次 render 都检查最新配置 fingerprint，与已渲染的 fingerprint 比较
-  const request = enabled ? buildRequest() : null
-  const currentFingerprint = request
-    ? request.template_id && request.asset_ids.length > 0
-      ? buildFingerprint(request)
-      : ""
-    : ""
-
-  // 首次进入自动触发
-  const didInitRef = useRef(false)
-  useEffect(() => {
-    if (!enabled || !currentFingerprint) {
-      didInitRef.current = false
-      // 禁用时取消进行中的轮询，避免回到前序步骤后仍在后台轮询
-      requestSeqRef.current += 1
-      clearTimers()
-      return
-    }
-    if (!didInitRef.current) {
-      didInitRef.current = true
-      renderedFingerprintRef.current = currentFingerprint
-      triggerPreview()
-    }
-  }, [enabled, currentFingerprint, triggerPreview, clearTimers])
-
-  // 配置变更检测：素材/配音/BGM 等变化 → 自动重渲染；标题样式变化 → 标记 stale
-  const prevFingerprintRef = useRef(currentFingerprint)
-  useEffect(() => {
-    if (!enabled || !currentFingerprint) return
-    const prev = prevFingerprintRef.current
-    prevFingerprintRef.current = currentFingerprint
-
-    if (!prev || prev === currentFingerprint) return
-    if (currentFingerprint === renderedFingerprintRef.current) return
-
-    // 配置已变更
-    // 判断是标题样式变更还是素材/配音/BGM 变更
-    const prevParsed = JSON.parse(prev) as Record<string, unknown>
-    const currParsed = JSON.parse(currentFingerprint) as Record<string, unknown>
-    const nonTitleChanged =
-      prevParsed.t !== currParsed.t ||
-      prevParsed.a !== currParsed.a ||
-      prevParsed.d !== currParsed.d ||
-      prevParsed.r !== currParsed.r ||
-      prevParsed.v !== currParsed.v ||
-      JSON.stringify(prevParsed.b) !== JSON.stringify(currParsed.b)
-
-    if (nonTitleChanged) {
-      // 素材/配音/BGM/模板等变化 → 自动重新渲染
-      renderedFingerprintRef.current = currentFingerprint
-      triggerPreview()
-    } else {
-      // 仅标题文字/样式变化 → 标记 stale，不自动重渲染（避免频繁请求）
-      // 实时预览由 CSS TitleOverlay 提供
-      setStatus((s) => (s === "ready" ? "stale" : s))
-    }
-  }, [enabled, currentFingerprint, triggerPreview])
-
-  return {
-    status,
-    videoUrl,
-    error,
-    progress,
-    triggerPreview,
-    taskId,
-  }
-}
-
-export default useServerPreview

apps/web/src/pages/generate/hooks/useVariantVoicePreview.ts

@@ -0,0 +1,166 @@
+/**
+ * 批量变体配音预览音频解析（#1750）
+ *
+ * 独立配音模式下每个变体挂载各自的配音 URL：
+ * - 配音素材（voice 资产，有 file_url）→ 直接用素材文件 URL；
+ * - AI 音色（预置/克隆，无实体文件）→ 按该变体自己的标题调 /tts/preview 合成；
+ * - 共用模式下所有变体解析为同一条（等价于旧 previewVoiceAudioUrl）。
+ *
+ * N=1 不使用本 hook（单视频配音预览逻辑在 GeneratePage 内保持不变，零回归）。
+ */
+import { useEffect, useRef, useState } from "react"
+import { useQuery } from "@tanstack/react-query"
+import { getAssetsByKind } from "@/api/assets"
+import type { AssetItem } from "@/api/assets"
+import { previewTts } from "@/api/tts"
+
+interface UseVariantVoicePreviewOptions {
+  /** 是否批量模式（count>1） */
+  enabled: boolean
+  /** 变体数量 */
+  count: number
+  /** 是否每个视频独立配音 */
+  perVideo: boolean
+  /** 共用配音 ID（独立模式下为变体 0 的配音） */
+  sharedVoiceId: string
+  /** 克隆音色 ID 覆盖（共用模式，与旧逻辑一致：selectedClonedVoice || selectedVoice） */
+  clonedVoiceId?: string
+  /** 各变体独立配音 ID（独立模式）；长度不足时回退共用 */
+  variantVoiceIds: string[]
+  /** 各变体标题（TTS 合成文案源） */
+  titles: string[]
+}
+
+/** 稳定的空数组常量：避免 useQuery 数据未就绪时每次渲染产生新引用导致 effect 无限触发 */
+const EMPTY_VOICE_MATERIALS: AssetItem[] = []
+
+/** 判断配音 ID 是否对应实体素材（有 file_url）；否则视为 AI 音色需 TTS */
+function findMaterialUrl(id: string, materials: AssetItem[]): string | null {
+  if (!id) return null
+  const m = materials.find((x) => x.id === id)
+  return m?.file_url || null
+}
+
+export function useVariantVoicePreview({
+  enabled,
+  count,
+  perVideo,
+  sharedVoiceId,
+  clonedVoiceId = "",
+  variantVoiceIds,
+  titles,
+}: UseVariantVoicePreviewOptions): (string | null)[] {
+  const [urls, setUrls] = useState<(string | null)[]>([])
+  // 配音素材库：组件内部自取，避免调用方传入不稳定数组引用导致 effect 反复触发
+  const { data: voiceMaterialsData } = useQuery({
+    queryKey: ["assets", "voice"],
+    queryFn: () => getAssetsByKind("voice", { limit: 50 }),
+  })
+  const voiceMaterials: AssetItem[] = voiceMaterialsData ?? EMPTY_VOICE_MATERIALS
+  // 已缓存的 TTS 结果：key = `${voiceId}|${title}`，避免重复合成
+  const ttsCacheRef = useRef<Map<string, string>>(new Map())
+  // 在途请求 AbortController
+  const abortRef = useRef<AbortController | null>(null)
+  const seqRef = useRef(0)
+
+  useEffect(() => {
+    if (!enabled || count <= 1) {
+      setUrls((prev) => (prev.length === 0 ? prev : []))
+      return
+    }
+
+    const seq = ++seqRef.current
+    abortRef.current?.abort()
+    const controller = new AbortController()
+    abortRef.current = controller
+
+    // 每个变体实际使用的配音 ID
+    const voiceIds = Array.from({ length: count }, (_, i) =>
+      perVideo ? variantVoiceIds[i] || sharedVoiceId : sharedVoiceId,
+    )
+
+    // 先用素材 URL 同步填充；AI 音色位置先置 null，待 TTS 完成
+    const result: (string | null)[] = voiceIds.map((id, i) => {
+      const materialUrl = findMaterialUrl(id, voiceMaterials)
+      if (materialUrl) return materialUrl
+      // 共用模式下克隆音色 ID 可能与 selectedVoice 不同（与旧 useEffect 逻辑一致）
+      if (!perVideo && i === 0 && clonedVoiceId) {
+        return findMaterialUrl(clonedVoiceId, voiceMaterials)
+      }
+      return null
+    })
+
+    // 收集需要 TTS 的变体：无素材 URL 且有标题且有音色 ID
+    const ttsJobs: { index: number; voiceId: string; title: string }[] = []
+    voiceIds.forEach((id, i) => {
+      if (result[i]) return
+      // 共用模式沿用旧逻辑：voice_id = selectedClonedVoice || selectedVoice
+      const ttsVoiceId = !perVideo && i === 0 ? clonedVoiceId || id : id
+      const title = titles[i] || ""
+      if (!ttsVoiceId || !title) return
+      ttsJobs.push({ index: i, voiceId: ttsVoiceId, title })
+    })
+
+    setUrls((prev) =>
+      prev.length === result.length && prev.every((v, i) => v === result[i]) ? prev : result,
+    )
+
+    if (ttsJobs.length === 0) return
+
+    let cancelled = false
+    void (async () => {
+      // 串行 TTS，避免瞬间 N 个合成请求打爆后端
+      for (const job of ttsJobs) {
+        const cacheKey = `${job.voiceId}|${job.title}`
+        const cached = ttsCacheRef.current.get(cacheKey)
+        if (cached) {
+          if (seq === seqRef.current) {
+            setUrls((prev) => {
+              if (prev[job.index] === cached) return prev
+              const next = [...prev]
+              next[job.index] = cached
+              return next
+            })
+          }
+          continue
+        }
+        try {
+          // eslint-disable-next-line no-await-in-loop
+          const res = await previewTts({ text: job.title, voice_id: job.voiceId })
+          if (cancelled || controller.signal.aborted || seq !== seqRef.current) return
+          const audioUrl = res.audio_url || ""
+          if (audioUrl) {
+            ttsCacheRef.current.set(cacheKey, audioUrl)
+            setUrls((prev) => {
+              if (prev[job.index] === audioUrl) return prev
+              const next = [...prev]
+              next[job.index] = audioUrl
+              return next
+            })
+          }
+        } catch (err) {
+          if (cancelled || controller.signal.aborted || seq !== seqRef.current) return
+          console.warn(`[变体${job.index + 1}预览配音生成失败]`, err)
+        }
+      }
+    })()
+
+    return () => {
+      cancelled = true
+      controller.abort()
+    }
+  }, [
+    enabled,
+    count,
+    perVideo,
+    sharedVoiceId,
+    clonedVoiceId,
+    variantVoiceIds,
+    titles,
+    voiceMaterials,
+  ])
+
+  return urls
+}
+
+export default useVariantVoicePreview

apps/web/src/pages/generate/utils/calculateTotalVideoDuration.ts

@@ -1,54 +0,0 @@
-/**
- * 共享：根据素材列表和模板片段计算总视频时长
- * GeneratePage（配音校验）和 FrontendPreviewPlayer（播放控制）共用
- */
-
-export interface DurationAsset {
-  id?: string
-  duration?: number
-  metadata?: { duration?: number }
-}
-
-export interface DurationTemplateSegment {
-  duration_min?: number
-  duration_max?: number
-}
-
-/**
- * 计算总视频时长
- * @param assets 素材列表
- * @param template 模板（含 segments）
- * @returns 总时长（秒），无有效数据时返回 0
- */
-export function calculateTotalVideoDuration(
-  assets: DurationAsset[] | undefined,
-  template: { segments?: DurationTemplateSegment[] } | undefined,
-): number {
-  if (!assets || assets.length === 0 || !template) return 0
-
-  const templateSegments = template.segments || []
-
-  return assets.reduce((sum, asset, i) => {
-    const assetDuration = asset.duration || asset.metadata?.duration || 30
-    const tplSeg = templateSegments[i] || templateSegments[templateSegments.length - 1]
-    const segDuration = tplSeg
-      ? Math.min(
-          tplSeg.duration_max ?? assetDuration,
-          Math.max(tplSeg.duration_min ?? 0, assetDuration),
-        )
-      : Math.min(assetDuration, 10)
-    return sum + segDuration
-  }, 0)
-}
-
-/**
- * 估算总视频时长（仅依赖模板 segments）
- * 当素材未加载或加载失败时，用各片段 duration_max 之和作为估算值
- * 确保配音时长校验不会因素材未就绪而跳过
- */
-export function estimateTotalVideoDuration(
-  template: { segments?: DurationTemplateSegment[] } | undefined,
-): number {
-  if (!template?.segments || template.segments.length === 0) return 0
-  return template.segments.reduce((sum, seg) => sum + (seg.duration_max || 0), 0)
-}

apps/web/src/pages/my-templates/components/TemplateCard.tsx

@@ -66,7 +66,7 @@ export const TemplateCard: React.FC<TemplateCardProps> = ({
 
     <div className="mt-card-meta">
       <Text type="secondary" style={{ fontSize: 12 }}>
-        {tpl.segments.length} 片段 · 预估 ~{tpl.estimated_duration}s
+        {tpl.segments.length} 个片段
       </Text>
       {tpl.category && <Tag style={{ fontSize: 11, marginTop: 4 }}>{tpl.category}</Tag>}
     </div>

apps/web/src/pages/my-templates/hooks/useMyTemplates.ts

@@ -57,11 +57,6 @@ export function useMyTemplates() {
         title_config: tpl.title_config,
         subtitle_config: tpl.subtitle_config,
         bgm_config: tpl.bgm_config,
-        estimated_duration:
-          tpl.estimated_duration ??
-          Math.round(
-            tpl.segments.reduce((s, seg) => s + (seg.duration_min + seg.duration_max) / 2, 0),
-          ),
         segments: tpl.segments.map(({ id: _id, ...rest }) => rest),
       }),
     onSuccess: () => {

apps/web/src/pages/templates/TemplateLibrary.tsx

@@ -1,7 +1,7 @@
 /**
  * 模板库页面（升级版）— V21 设计系统
  * 对接后端模板管理 API：
- * - 分页查询（page/page_size/category/keyword/duration_range）
+ * - 分页查询（page/page_size/category/keyword）
  * - 模板详情（素材规则、字幕样式、BGM、比例等参数配置）
  * - 复制模板 / 从模板生成
  * - 卡片网格布局 + 类型筛选 + 搜索 + 收藏
@@ -24,7 +24,6 @@ const TemplateLibrary: React.FC = () => {
     error,
     searchText,
     activeType,
-    durationRange,
     page,
     pageSize,
     setPage,
@@ -34,7 +33,6 @@ const TemplateLibrary: React.FC = () => {
     handleCreate,
     handleSearchChange,
     handleCategoryChange,
-    handleDurationChange,
   } = useTemplateLibrary()
 
   const {
@@ -62,8 +60,6 @@ const TemplateLibrary: React.FC = () => {
         onSearchChange={handleSearchChange}
         activeType={activeType}
         onTypeChange={handleCategoryChange}
-        durationRange={durationRange}
-        onDurationChange={handleDurationChange}
       />
 
       {/* 模板展示区 */}
@@ -77,7 +73,6 @@ const TemplateLibrary: React.FC = () => {
         errorMessage={error?.message}
         searchText={searchText}
         activeType={activeType}
-        durationRange={durationRange}
         onPageChange={setPage}
         onPreview={handlePreview}
         onToggleFavorite={toggleFavorite}

apps/web/src/pages/templates/components/template-library/TemplateCard.tsx

@@ -1,7 +1,7 @@
 import React from "react"
 import { Tag } from "antd"
 import type { TemplateItem } from "@/api/templates"
-import { gradientForCategory, getTypeColor, formatDuration } from "../../utils/templateLibrary"
+import { gradientForCategory, getTypeColor } from "../../utils/templateLibrary"
 
 interface TemplateCardProps {
   template: TemplateItem
@@ -37,7 +37,7 @@ export const TemplateCard: React.FC<TemplateCardProps> = ({
         <div className="xx-template-thumb-name">{template.name}</div>
         <div className="xx-template-thumb-meta">
           <span className="xx-template-thumb-duration">
-            {formatDuration(template.estimated_duration ?? template.target_duration)}
+            {template.clip_count || template.segments?.length || 0} 个片段
           </span>
         </div>
         <div className="xx-template-preview-hint">点击查看详情</div>

apps/web/src/pages/templates/components/template-library/TemplateDetailModal.tsx

@@ -5,9 +5,8 @@ import PreviewArea from "./template-detail-modal/PreviewArea"
 import SegmentList from "./template-detail-modal/SegmentList"
 import StyleConfig from "./template-detail-modal/StyleConfig"
 import DetailFooter from "./template-detail-modal/DetailFooter"
-import { getTypeColor, formatDuration } from "../../utils/templateLibrary"
+import { getTypeColor } from "../../utils/templateLibrary"
 import { TEMPLATE_TYPES } from "../../constants/templateLibrary"
-import { calcTotalSegmentDuration } from "../../utils/templateLibrary"
 
 export const TemplateDetailModal: React.FC<TemplateDetailModalProps> = ({
   template,
@@ -18,7 +17,6 @@ export const TemplateDetailModal: React.FC<TemplateDetailModalProps> = ({
   onCopy,
 }) => {
   const segments = template.segments ?? []
-  const totalSegmentDuration = calcTotalSegmentDuration(segments)
   const typeInfo = TEMPLATE_TYPES.find((t) => t.type === template.category)
 
   return (
@@ -64,11 +62,6 @@ export const TemplateDetailModal: React.FC<TemplateDetailModalProps> = ({
             size="small"
             className="xx-template-modal-desc-table"
             items={[
-              {
-                key: "duration",
-                label: "目标时长",
-                children: formatDuration(template.estimated_duration ?? template.target_duration),
-              },
               {
                 key: "clips",
                 label: "片段数量",
@@ -87,7 +80,7 @@ export const TemplateDetailModal: React.FC<TemplateDetailModalProps> = ({
             ]}
           />
 
-          <SegmentList segments={segments} totalDuration={totalSegmentDuration} />
+          <SegmentList segments={segments} />
           <StyleConfig template={template} />
           <DetailFooter
             template={template}

apps/web/src/pages/templates/components/template-library/TemplateGrid.tsx

@@ -14,7 +14,6 @@ interface TemplateGridProps {
   errorMessage?: string
   searchText: string
   activeType: string
-  durationRange: string
   onPageChange: (page: number) => void
   onPreview: (template: TemplateItem) => void
   onToggleFavorite: (id: string, e: React.MouseEvent) => void
@@ -31,7 +30,6 @@ export const TemplateGrid: React.FC<TemplateGridProps> = ({
   errorMessage,
   searchText,
   activeType,
-  durationRange,
   onPageChange,
   onPreview,
   onToggleFavorite,
@@ -64,7 +62,7 @@ export const TemplateGrid: React.FC<TemplateGridProps> = ({
 
   // 空状态
   if (templates.length === 0) {
-    const hasFilter = !!searchText || activeType !== "全部" || !!durationRange
+    const hasFilter = !!searchText || activeType !== "全部"
     return (
       <div className="xx-templates-empty">
         <div className="xx-templates-empty-icon">

apps/web/src/pages/templates/components/template-library/TemplateToolbar.tsx

@@ -1,15 +1,13 @@
 import React from "react"
 import { SearchOutlined } from "@ant-design/icons"
-import type { EditTemplateType, DurationRange } from "../../types/templateLibrary"
-import { TEMPLATE_TYPES, DURATION_OPTIONS } from "../../constants/templateLibrary"
+import type { EditTemplateType } from "../../types/templateLibrary"
+import { TEMPLATE_TYPES } from "../../constants/templateLibrary"
 
 interface TemplateToolbarProps {
   searchText: string
   onSearchChange: (e: React.ChangeEvent<HTMLInputElement>) => void
   activeType: EditTemplateType | "全部"
   onTypeChange: (type: EditTemplateType | "全部") => void
-  durationRange: DurationRange
-  onDurationChange: (value: DurationRange) => void
 }
 
 export const TemplateToolbar: React.FC<TemplateToolbarProps> = ({
@@ -17,8 +15,6 @@ export const TemplateToolbar: React.FC<TemplateToolbarProps> = ({
   onSearchChange,
   activeType,
   onTypeChange,
-  durationRange,
-  onDurationChange,
 }) => {
   return (
     <div className="xx-templates-toolbar">
@@ -46,18 +42,8 @@ export const TemplateToolbar: React.FC<TemplateToolbarProps> = ({
           </button>
         ))}
       </div>
-      {/* 时长筛选 */}
-      <div className="xx-templates-duration-filter">
-        {DURATION_OPTIONS.map((opt) => (
-          <button
-            key={opt.value}
-            className={`xx-templates-duration-btn${durationRange === opt.value ? " active" : ""}`}
-            onClick={() => onDurationChange(opt.value)}
-          >
-            {opt.label}
-          </button>
-        ))}
-      </div>
     </div>
   )
 }
+
+export default TemplateToolbar

apps/web/src/pages/templates/components/template-library/template-detail-modal/SegmentList.tsx

@@ -1,15 +1,13 @@
 import React from "react"
-import { Tooltip } from "antd"
 import type { TemplateSegment } from "@/api/templates"
-import { getMaterialTypeLabel, getTypeColor, formatDuration } from "../../../utils/templateLibrary"
+import { getMaterialTypeLabel, getTypeColor } from "../../../utils/templateLibrary"
 
 interface SegmentListProps {
   segments: TemplateSegment[]
-  totalDuration: number
 }
 
-/** 素材规则 / 片段列表 */
-const SegmentList: React.FC<SegmentListProps> = ({ segments, totalDuration }) => {
+/** 素材规则 / 片段列表（#1750：模板只定片段数/结构，无时长概念） */
+const SegmentList: React.FC<SegmentListProps> = ({ segments }) => {
   if (segments.length === 0) return null
 
   return (
@@ -35,17 +33,9 @@ const SegmentList: React.FC<SegmentListProps> = ({ segments, totalDuration }) =>
               <span className="xx-template-modal-clip-desc">
                 {seg.description || `片段 ${seg.segment_order}`}
               </span>
-              <Tooltip title={`时长范围: ${seg.duration_min}秒 - ${seg.duration_max}秒`}>
-                <span className="xx-template-modal-clip-duration">
-                  {seg.duration_min}-{seg.duration_max}秒
-                </span>
-              </Tooltip>
             </div>
           ))}
       </div>
-      <div className="xx-template-modal-total-duration">
-        预估总时长：{formatDuration(Math.round(totalDuration))}
-      </div>
     </div>
   )
 }

apps/web/src/pages/templates/constants/templateLibrary.ts

@@ -1,4 +1,4 @@
-import type { EditTemplateType, DurationRange } from "../types/templateLibrary"
+import type { EditTemplateType } from "../types/templateLibrary"
 
 export const TEMPLATE_TYPES: Array<{
   type: EditTemplateType | "全部"
@@ -15,16 +15,6 @@ export const TEMPLATE_TYPES: Array<{
   { type: "Vlog", label: "Vlog", icon: "📹", color: "#ec4899" },
 ]
 
-export const DURATION_OPTIONS: Array<{
-  value: DurationRange
-  label: string
-}> = [
-  { value: "", label: "全部时长" },
-  { value: "short", label: "30秒以内" },
-  { value: "medium", label: "30秒-2分钟" },
-  { value: "long", label: "2分钟以上" },
-]
-
 export const MATERIAL_TYPE_LABELS: Record<string, string> = {
   video: "视频",
   image: "图片",

apps/web/src/pages/templates/hooks/useTemplateLibrary.ts

@@ -9,7 +9,7 @@ import {
   type TemplateItem,
   type TemplateListParams,
 } from "@/api/templates"
-import type { EditTemplateType, DurationRange } from "../types/templateLibrary"
+import type { EditTemplateType } from "../types/templateLibrary"
 import { DEFAULT_PAGE_SIZE } from "../constants/templateLibrary"
 
 export const useTemplateLibrary = () => {
@@ -19,7 +19,6 @@ export const useTemplateLibrary = () => {
   /* 筛选状态 */
   const [searchText, setSearchText] = useState("")
   const [activeType, setActiveType] = useState<EditTemplateType | "全部">("全部")
-  const [durationRange, setDurationRange] = useState<DurationRange>("")
   const [page, setPage] = useState(1)
   const [pageSize] = useState(DEFAULT_PAGE_SIZE)
 
@@ -31,9 +30,8 @@ export const useTemplateLibrary = () => {
     }
     if (activeType !== "全部") params.category = activeType
     if (searchText.trim()) params.keyword = searchText.trim()
-    if (durationRange) params.duration_range = durationRange
     return params
-  }, [page, pageSize, activeType, searchText, durationRange])
+  }, [page, pageSize, activeType, searchText])
 
   /* 获取模板列表 */
   const {
@@ -112,12 +110,6 @@ export const useTemplateLibrary = () => {
     setPage(1)
   }, [])
 
-  /* 切换时长筛选 */
-  const handleDurationChange = useCallback((value: DurationRange) => {
-    setDurationRange(value)
-    setPage(1)
-  }, [])
-
   return {
     /* 状态 */
     templates,
@@ -127,7 +119,6 @@ export const useTemplateLibrary = () => {
     error,
     searchText,
     activeType,
-    durationRange,
     page,
     pageSize,
     /* mutations */
@@ -142,6 +133,5 @@ export const useTemplateLibrary = () => {
     handleCreate,
     handleSearchChange,
     handleCategoryChange,
-    handleDurationChange,
   }
 }

apps/web/src/pages/templates/types/templateLibrary.ts

@@ -2,7 +2,6 @@
 export type EditTemplateType = "口播" | "种草" | "产品" | "品牌" | "混剪" | "Vlog"
 
 /** 时长筛选值 */
-export type DurationRange = "" | "short" | "medium" | "long"
 
 /** 配置展示字段 */
 export interface ConfigDisplayFields {

apps/web/src/pages/templates/utils/templateLibrary.ts

@@ -5,7 +5,6 @@ import {
   DEFAULT_GRADIENT,
   MATERIAL_TYPE_LABELS,
 } from "../constants/templateLibrary"
-import type { TemplateSegment } from "@/api/templates"
 
 /** 获取类型对应颜色 */
 export const getTypeColor = (type: string): string => {
@@ -18,16 +17,6 @@ export const gradientForCategory = (category: string): string => {
   return CATEGORY_GRADIENT_MAP[category] ?? DEFAULT_GRADIENT
 }
 
-/** 格式化时长 */
-export const formatDuration = (seconds: number | undefined | null): string => {
-  if (!seconds || seconds <= 0) return "0秒"
-  const totalSec = Math.round(seconds)
-  const m = Math.floor(totalSec / 60)
-  const s = totalSec % 60
-  if (m === 0) return `${s}秒`
-  return `${m}分${s > 0 ? `${s}秒` : ""}`
-}
-
 /** 格式化配置对象为可读文本 */
 export const formatConfig = (config?: object): string => {
   if (!config || Object.keys(config).length === 0) return "默认"
@@ -47,8 +36,3 @@ export const getMaterialTypeLabel = (materialType: string | null | undefined): s
   if (!materialType) return "不限"
   return MATERIAL_TYPE_LABELS[materialType] ?? materialType
 }
-
-/** 计算片段总时长（取每个片段 min/max 的平均值） */
-export const calcTotalSegmentDuration = (segments: TemplateSegment[]): number => {
-  return segments.reduce((sum, s) => sum + (s.duration_min + s.duration_max) / 2, 0)
-}

apps/web/src/test/pages/generate/CanvasPreviewGrid.audio.test.tsx

@@ -0,0 +1,176 @@
+/**
+ * CanvasPreviewGrid 单测（Issue #1741 / #1750）
+ *
+ * 验证：
+ * - N=3 时每个变体都拿到各自的 voiceAudioUrls[i]（独立配音模式，null=TTS 合成中）
+ * - 每个变体都拿到各自的后端真实片段 variantClips[i]（serverClips），playToken 为 0 基变体序号
+ * - 每个变体都收到 activePlayToken / onPlayTokenChange（播放互斥接线）
+ * - 某个实例上报播放 → 所有实例的 activePlayToken 变为该实例（其他实例收到 token≠自身，自动暂停）
+ * - 实例上报暂停（null）→ 播放权释放
+ * - #1750 变体计划申请失败：渲染 role=alert 错误占位 ×N（严禁假数据/不渲染播放器），
+ *   「重试」按钮仅变体 0 卡片出现且点击触发 onRetryClips
+ * - #1750 加载态：渲染加载占位，不渲染播放器
+ */
+import { describe, it, expect, beforeEach, vi } from "vitest"
+import { render, fireEvent, screen } from "@testing-library/react"
+import type { AssetItem } from "@/api/assets"
+import type { EditPlanClip } from "@/api/template-editor"
+
+const playerCalls = vi.hoisted(() => [] as Array<Record<string, unknown>>)
+
+vi.mock("@/pages/generate/components/FrontendPreviewPlayer", () => ({
+  default: (props: Record<string, unknown>) => {
+    playerCalls.push(props)
+    const token = props.playToken as number
+    const active = props.activePlayToken as number | null
+    const change = props.onPlayTokenChange as (t: number | null) => void
+    return (
+      <div data-testid={`player-${token}`}>
+        <span data-testid={`voice-${token}`}>{props.voiceAudioUrl ? "has-voice" : "no-voice"}</span>
+        <span data-testid={`token-${token}`}>{active == null ? "none" : String(active)}</span>
+        <button type="button" onClick={() => change(token)}>
+          play-{token}
+        </button>
+        <button type="button" onClick={() => change(null)}>
+          pause-{token}
+        </button>
+      </div>
+    )
+  },
+}))
+
+import CanvasPreviewGrid from "@/pages/generate/components/CanvasPreviewGrid"
+
+function makeAsset(id: string): AssetItem {
+  return {
+    id,
+    library_id: "lib-1",
+    name: `${id}.mp4`,
+    storage_key: `media/${id}.mp4`,
+    file_url: `https://cdn.example.com/${id}.mp4`,
+    mime_type: "video/mp4",
+    metadata: { duration: 10 },
+    duration: 10,
+  }
+}
+
+function makeClips(variant: number): EditPlanClip[] {
+  return ["a1", "a2"].map((assetId, order) => ({
+    id: `clip-v${variant}-${assetId}`,
+    plan_id: `plan-${variant}`,
+    clip_type: "main",
+    order,
+    asset_id: assetId,
+    text_content: "",
+    start_time: 0,
+    duration: 5,
+    transition_effect: "none",
+    transition_duration: 0,
+    playback_speed: 1,
+    status: "ready",
+    config: {},
+  }))
+}
+
+const titleSettings = {
+  size: 36,
+  font: "思源黑体",
+  color: "#fff",
+  position: "bottom" as const,
+  bold: false,
+  italic: false,
+  stroke: true,
+  shadow: false,
+  posX: null,
+  posY: null,
+}
+
+const variantClips: EditPlanClip[][] = [makeClips(0), makeClips(1), makeClips(2)]
+
+function renderGrid(overrides: Record<string, unknown> = {}) {
+  playerCalls.length = 0
+  return render(
+    <CanvasPreviewGrid
+      count={3}
+      assets={[makeAsset("a1"), makeAsset("a2"), makeAsset("a3")]}
+      videoRatio="9:16"
+      titles={["标题1", "标题2", "标题3"]}
+      titleSettings={titleSettings}
+      variantClips={variantClips}
+      voiceAudioUrls={["https://cdn.example.com/v0.mp3", null, "https://cdn.example.com/v2.mp3"]}
+      selectedIds={[0, 1, 2]}
+      onToggleSelect={() => {}}
+      {...overrides}
+    />,
+  )
+}
+
+describe("CanvasPreviewGrid 配音、真实片段与播放互斥 (#1741/#1750)", () => {
+  beforeEach(() => {
+    playerCalls.length = 0
+  })
+
+  it("N=3 时每个变体都拿到各自的配音 URL 与后端真实片段，playToken 为 0 基序号", () => {
+    renderGrid()
+    expect(playerCalls).toHaveLength(3)
+    playerCalls.forEach((p, i) => {
+      expect(p.playToken).toBe(i)
+      expect(p.serverClips).toBe(variantClips[i])
+      expect(p.variantTitle).toBe(`标题${i + 1}`)
+    })
+    // 独立配音：变体 0/2 有各自 URL；变体 1 为 null（TTS 合成中）→ 传 undefined
+    expect(playerCalls[0].voiceAudioUrl).toBe("https://cdn.example.com/v0.mp3")
+    expect(playerCalls[1].voiceAudioUrl).toBeUndefined()
+    expect(playerCalls[2].voiceAudioUrl).toBe("https://cdn.example.com/v2.mp3")
+    // 配音状态徽标
+    expect(screen.getByTestId("voice-0").textContent).toBe("has-voice")
+    expect(screen.getByTestId("voice-1").textContent).toBe("no-voice")
+    expect(screen.getByTestId("voice-2").textContent).toBe("has-voice")
+  })
+
+  it("每个变体都接线 activePlayToken / onPlayTokenChange", () => {
+    renderGrid()
+    playerCalls.forEach((p) => {
+      expect(p.activePlayToken).toBeNull()
+      expect(typeof p.onPlayTokenChange).toBe("function")
+    })
+  })
+
+  it("点击变体2播放：所有实例 activePlayToken 变为 1（0 基，其他实例自动暂停）", () => {
+    renderGrid()
+    fireEvent.click(screen.getByTestId("player-1").querySelector("button")!)
+    expect(screen.getByTestId("token-0").textContent).toBe("1")
+    expect(screen.getByTestId("token-1").textContent).toBe("1")
+    expect(screen.getByTestId("token-2").textContent).toBe("1")
+  })
+
+  it("正在播放实例上报暂停后，播放权释放（token 回 null）", () => {
+    renderGrid()
+    fireEvent.click(screen.getByTestId("player-2").querySelector("button")!)
+    expect(screen.getByTestId("token-0").textContent).toBe("2")
+
+    fireEvent.click(screen.getByTestId("player-2").querySelectorAll("button")[1])
+    expect(screen.getByTestId("token-2").textContent).toBe("none")
+  })
+
+  it("clipsError：每张卡片显示错误占位（role=alert）且不渲染任何播放器，重试按钮仅一个并触发回调", () => {
+    const onRetry = vi.fn()
+    renderGrid({ clipsError: true, onRetryClips: onRetry })
+    expect(screen.getAllByRole("alert")).toHaveLength(3)
+    expect(screen.getAllByText("预览加载失败，请重试")).toHaveLength(3)
+    // 严禁假数据：错误态不渲染播放器
+    expect(playerCalls).toHaveLength(0)
+    // 重试按钮仅变体 0 卡片出现
+    const retryButtons = screen.getAllByText("重试")
+    expect(retryButtons).toHaveLength(1)
+    fireEvent.click(retryButtons[0])
+    expect(onRetry).toHaveBeenCalledTimes(1)
+  })
+
+  it("clipsLoading：渲染加载占位，不渲染播放器", () => {
+    renderGrid({ clipsLoading: true })
+    expect(screen.getAllByText("独立选片中…")).toHaveLength(3)
+    expect(screen.queryAllByRole("alert")).toHaveLength(0)
+    expect(playerCalls).toHaveLength(0)
+  })
+})

apps/web/src/test/pages/generate/FrontendPreviewPlayer.audio.test.tsx

@@ -0,0 +1,213 @@
+/**
+ * FrontendPreviewPlayer 音频行为单测（Issue #1741 / #1750）
+ *
+ * useSegmentScheduler/useCanvasPlayer 用 mock 控制播放态，专注验证本组件的音频逻辑：
+ * - 有配音时 video 保持 muted（素材原声不与配音混音）
+ * - 无配音时 video 不 muted（素材原声兜底，保证任何情况下播放有声）
+ * - 静音按钮：默认有声；点击后切 muted，aria-label 与图标切换
+ * - 批量播放互斥（#1750 playToken 为 0 基变体序号）：activePlayToken 变为其他实例且本实例在播放时，调用 pause
+ * - 点击播放/暂停时上报播放权（onPlayTokenChange）
+ * - #1750：serverClips 是唯一片段来源，缺失时不渲染任何 video（无本地模拟 fallback）
+ */
+import { describe, it, expect, beforeEach, vi } from "vitest"
+import { render, screen, fireEvent } from "@testing-library/react"
+import FrontendPreviewPlayer from "@/pages/generate/components/FrontendPreviewPlayer"
+import type { AssetItem } from "@/api/assets"
+import type { EditPlanClip } from "@/api/template-editor"
+
+const mocks = vi.hoisted(() => ({
+  isPlaying: false,
+  pause: vi.fn(),
+  togglePlayPause: vi.fn(),
+}))
+
+vi.mock("@/pages/generate/hooks/useSegmentScheduler", () => ({
+  // segments 由组件 buildPlaybackSegments 产出（唯一来源 serverClips）；
+  // canPlay 与真实 hook 一致：无片段时不可播放
+  useSegmentScheduler: vi.fn((segments: unknown[]) => ({
+    isPlaying: mocks.isPlaying,
+    currentTime: 0,
+    totalDuration: 20,
+    currentSegmentIndex: 0,
+    canPlay: segments.length > 0,
+    togglePlayPause: mocks.togglePlayPause,
+    seekTo: vi.fn(),
+    pause: mocks.pause,
+    videoRefs: { current: [] as (HTMLVideoElement | null)[] },
+  })),
+}))
+
+vi.mock("@/pages/generate/hooks/useCanvasPlayer", () => ({
+  useCanvasPlayer: () => ({
+    state: {
+      isPlaying: false,
+      isReady: false,
+      isBuffering: false,
+      currentTime: 0,
+      duration: 0,
+      errorMessage: "",
+      hasDecodeError: false,
+    },
+    controls: { play: vi.fn(), pause: vi.fn(), seek: vi.fn() },
+  }),
+}))
+
+beforeEach(() => {
+  mocks.isPlaying = false
+  mocks.pause.mockClear()
+  mocks.togglePlayPause.mockClear()
+  vi.stubGlobal(
+    "ResizeObserver",
+    class {
+      observe() {}
+      unobserve() {}
+      disconnect() {}
+    },
+  )
+})
+
+function makeAsset(id: string): AssetItem {
+  return {
+    id,
+    library_id: "lib-1",
+    name: `${id}.mp4`,
+    storage_key: `media/${id}.mp4`,
+    file_url: `https://cdn.example.com/${id}.mp4`,
+    mime_type: "video/mp4",
+    metadata: { duration: 10, width: 1080, height: 1920 },
+    duration: 10,
+  }
+}
+
+function makeClip(assetId: string, order: number): EditPlanClip {
+  return {
+    id: `clip-${assetId}`,
+    plan_id: "plan-1",
+    clip_type: "main",
+    order,
+    asset_id: assetId,
+    text_content: "",
+    start_time: 0,
+    duration: 5,
+    transition_effect: "none",
+    transition_duration: 0,
+    playback_speed: 1,
+    status: "ready",
+    config: {},
+  }
+}
+
+const serverClips = [makeClip("a1", 0), makeClip("a2", 1)]
+
+const baseProps = {
+  assets: [makeAsset("a1"), makeAsset("a2")],
+  videoRatio: "9:16",
+  ready: true,
+  serverClips,
+}
+
+function videos(): HTMLVideoElement[] {
+  return Array.from(document.querySelectorAll("video"))
+}
+
+describe("FrontendPreviewPlayer 音频行为 (#1741/#1750)", () => {
+  it("有配音时 video 保持 muted（素材原声不与配音混音）", () => {
+    render(<FrontendPreviewPlayer {...baseProps} voiceAudioUrl="https://cdn.example.com/tts.mp3" />)
+    expect(videos()).toHaveLength(2)
+    videos().forEach((v) => expect(v.muted).toBe(true))
+  })
+
+  it("无配音时 video 不 muted（素材原声兜底）", () => {
+    render(<FrontendPreviewPlayer {...baseProps} />)
+    videos().forEach((v) => expect(v.muted).toBe(false))
+  })
+
+  it("无配音时点静音按钮，video 切换为 muted；再点恢复", () => {
+    render(<FrontendPreviewPlayer {...baseProps} />)
+    const vs = videos()
+    expect(vs[0].muted).toBe(false)
+
+    fireEvent.click(screen.getByRole("button", { name: "静音" }))
+    videos().forEach((v) => expect(v.muted).toBe(true))
+
+    fireEvent.click(screen.getByRole("button", { name: "取消静音" }))
+    videos().forEach((v) => expect(v.muted).toBe(false))
+  })
+
+  it("批量播放互斥：token 变为其他实例且本实例在播放时调用 pause", () => {
+    mocks.isPlaying = true
+    const { rerender } = render(
+      <FrontendPreviewPlayer
+        {...baseProps}
+        playToken={1}
+        activePlayToken={1}
+        onPlayTokenChange={() => {}}
+        compact
+      />,
+    )
+    expect(mocks.pause).not.toHaveBeenCalled()
+
+    // 播放权切给实例 2（0 基 token）
+    rerender(
+      <FrontendPreviewPlayer
+        {...baseProps}
+        playToken={1}
+        activePlayToken={2}
+        onPlayTokenChange={() => {}}
+        compact
+      />,
+    )
+    expect(mocks.pause).toHaveBeenCalledTimes(1)
+
+    // token 切回自己：不重复暂停
+    rerender(
+      <FrontendPreviewPlayer
+        {...baseProps}
+        playToken={1}
+        activePlayToken={1}
+        onPlayTokenChange={() => {}}
+        compact
+      />,
+    )
+    expect(mocks.pause).toHaveBeenCalledTimes(1)
+  })
+
+  it("未播放时 token 变化不触发暂停（effect 仅在本实例播放时生效）", () => {
+    // mocks.isPlaying = false（beforeEach 重置）
+    const { rerender } = render(
+      <FrontendPreviewPlayer {...baseProps} playToken={0} activePlayToken={0} compact />,
+    )
+    rerender(<FrontendPreviewPlayer {...baseProps} playToken={0} activePlayToken={1} compact />)
+    expect(mocks.pause).not.toHaveBeenCalled()
+  })
+
+  it("暂停状态下点击播放按钮：上报播放权为自身 playToken 并触发播放", () => {
+    const onToken = vi.fn()
+    render(
+      <FrontendPreviewPlayer {...baseProps} playToken={2} onPlayTokenChange={onToken} compact />,
+    )
+    // 暂停态有两个图标播放按钮（中央大按钮 + 控制条按钮），均调 handleTogglePlay，点中央那个
+    const playButtons = screen.getAllByRole("button").filter((b) => !b.getAttribute("aria-label"))
+    expect(playButtons.length).toBeGreaterThanOrEqual(1)
+    fireEvent.click(playButtons[0])
+    expect(onToken).toHaveBeenCalledWith(2)
+    expect(mocks.togglePlayPause).toHaveBeenCalledTimes(1)
+  })
+
+  it("每个卡片都渲染独立静音按钮", () => {
+    render(
+      <div>
+        <FrontendPreviewPlayer {...baseProps} playToken={0} compact />
+        <FrontendPreviewPlayer {...baseProps} playToken={1} compact />
+        <FrontendPreviewPlayer {...baseProps} playToken={2} compact />
+      </div>,
+    )
+    expect(screen.getAllByRole("button", { name: "静音" })).toHaveLength(3)
+  })
+
+  it("#1750 serverClips 缺失时不渲染任何 video（无本地模拟 fallback，显示无可播放素材）", () => {
+    render(<FrontendPreviewPlayer {...baseProps} serverClips={undefined} />)
+    expect(videos()).toHaveLength(0)
+    expect(screen.getByText("暂无可播放素材")).toBeInTheDocument()
+  })
+})

apps/web/src/test/pages/generate/smart-match-pool.test.ts

@@ -0,0 +1,40 @@
+/**
+ * 智能匹配候选池数量规则单测（#1744/#1750）
+ *
+ * #1750 基线：模板只有片段数/结构、没有时长概念——候选池纯按「片段数 × 3」
+ * （每个片段至少 3 个候选供变体间洗牌避让），不再参考任何 duration 字段；
+ * 结果钳制到 [1, 200]（后端 limit 上限 200）；无片段信息时兜底 30。
+ */
+import { describe, it, expect } from "vitest"
+import { computeLimitFromSegments } from "@/pages/generate/hooks/step2-materials/useSmartMatch"
+import type { TemplateSegment } from "@/api/templates/types"
+
+function segs(n: number): TemplateSegment[] {
+  // 新规则只看片段数量，duration 字段已废弃，这里不再构造
+  return Array.from({ length: n }, () => ({}) as TemplateSegment)
+}
+
+describe("computeLimitFromSegments (#1750 候选池 = 片段数×3）", () => {
+  it("无 segments 时返回兜底 30", () => {
+    expect(computeLimitFromSegments(undefined)).toBe(30)
+    expect(computeLimitFromSegments([])).toBe(30)
+  })
+
+  it("候选池 = 片段数 × 3（与任何时长字段无关）", () => {
+    expect(computeLimitFromSegments(segs(1))).toBe(3)
+    expect(computeLimitFromSegments(segs(3))).toBe(9)
+    expect(computeLimitFromSegments(segs(5))).toBe(15)
+    expect(computeLimitFromSegments(segs(10))).toBe(30)
+  })
+
+  it("超过上限钳制为 200（后端 limit 上限）", () => {
+    expect(computeLimitFromSegments(segs(67))).toBe(200) // 67×3=201 → 200
+    expect(computeLimitFromSegments(segs(100))).toBe(200) // 100×3=300 → 200
+  })
+
+  it("任何正常片段数下 limit 均 ≥ 1", () => {
+    for (let n = 0; n <= 10; n++) {
+      expect(computeLimitFromSegments(segs(n))).toBeGreaterThanOrEqual(1)
+    }
+  })
+})

apps/web/src/test/pages/generate/smoke.test.tsx

@@ -5,7 +5,6 @@
  *
  * 重构记录：
  * - useStep2Materials 拆分为 useMaterialLibrary + useSmartMatch 子 Hook
- * - Phase1 预览生成：新增 generation API 层 + PreviewVideoPanel
  */
 import { describe, it, expect } from "vitest"
 
@@ -23,8 +22,6 @@ import "@/pages/generate/components/Step3VoiceWithMode"
 import "@/pages/generate/components/CanvasPreviewGrid"
 import "@/pages/generate/components/BatchGenerationGrid"
 import "@/pages/generate/components/PreviewCountModal"
-import "@/pages/generate/components/PreviewVideoPanel"
-import "@/pages/generate/components/GenerateResultPanel"
 import "@/pages/generate/components/GenerateStepContent"
 import "@/pages/generate/components/voice/VoiceRecommendSection"
 import "@/pages/generate/components/voice/VoiceChoiceCard"
@@ -50,6 +47,8 @@ describe("GeneratePage module smoke test", () => {
 })
 import "@/pages/generate/hooks/useGenerateVideo"
 import "@/pages/generate/hooks/useBatchCovers"
+import "@/pages/generate/hooks/useBatchVariantPlans"
+import "@/pages/generate/hooks/useVariantVoicePreview"
 import "@/pages/generate/hooks/usePreviewAssets"
 import "@/pages/generate/hooks/useSegmentScheduler"
 import "@/pages/generate/hooks/generate-video/useGenerationPolling"

apps/web/src/test/pages/generate/useBatchVariantPlans.test.tsx

@@ -0,0 +1,230 @@
+/**
+ * useBatchVariantPlans 单测（#1750 修正：严禁假数据冒充预览）
+ * - 批量（N>1）时向后端申请变体计划，返回 clips/planIds
+ * - 404（端点未上线）/ 400（参数错误）/ 网络错误：一律 error=true，UI 可重试
+ * - 数据不完整（某变体 clips 为空）：error=true
+ * - retry() 重新发起请求，成功后 ready=true
+ * - N=1 / 无素材 / disabled 不发请求
+ * - 入参变化重新申请；未变化不重复请求
+ */
+import { describe, it, expect, vi, beforeEach } from "vitest"
+import { renderHook, waitFor, act } from "@testing-library/react"
+import { useBatchVariantPlans } from "@/pages/generate/hooks/useBatchVariantPlans"
+import type { EditPlanClip } from "@/api/template-editor"
+
+vi.mock("@/api/generation/variantPlans", () => ({
+  createBatchVariantPlans: vi.fn(),
+}))
+
+import { createBatchVariantPlans } from "@/api/generation/variantPlans"
+
+const mockCreate = vi.mocked(createBatchVariantPlans)
+
+function makeClip(
+  partial: Partial<EditPlanClip> & { asset_id: string; order: number },
+): EditPlanClip {
+  return {
+    id: `clip-${partial.asset_id}-${partial.order}`,
+    plan_id: "plan-x",
+    clip_type: "main",
+    start_time: 0,
+    duration: 5,
+    text_content: "",
+    transition_effect: "",
+    transition_duration: 0,
+    playback_speed: 1,
+    status: "ready",
+    config: {},
+    ...partial,
+  }
+}
+
+function buildResp(count: number) {
+  return {
+    total: count,
+    items: Array.from({ length: count }, (_, i) => ({
+      variant_index: i,
+      plan_id: `plan-${i}`,
+      clips: [makeClip({ asset_id: `a${(i % 3) + 1}`, order: 0, start_time: i * 2 })],
+    })),
+  }
+}
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mockCreate.mockReset()
+})
+
+describe("useBatchVariantPlans (#1750 错误态)", () => {
+  it("批量 N=3 时申请变体计划并返回按索引对齐的 clips/planIds", async () => {
+    mockCreate.mockResolvedValueOnce(buildResp(3))
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({
+        enabled: true,
+        count: 3,
+        templateId: "tpl-1",
+        assetIds: ["a1", "a2", "a3"],
+        sourcePlanId: "plan-src",
+      }),
+    )
+
+    await waitFor(() => expect(result.current.ready).toBe(true))
+    expect(mockCreate).toHaveBeenCalledTimes(1)
+    expect(mockCreate).toHaveBeenCalledWith({
+      template_id: "tpl-1",
+      asset_ids: ["a1", "a2", "a3"],
+      count: 3,
+      source_edit_plan_id: "plan-src",
+    })
+    expect(result.current.planIdsByVariant).toEqual(["plan-0", "plan-1", "plan-2"])
+    expect(result.current.clipsByVariant[1]?.[0]?.start_time).toBe(2)
+    expect(result.current.error).toBe(false)
+    expect(result.current.loading).toBe(false)
+  })
+
+  it("sourcePlanId 为空时不传 source_edit_plan_id 字段", async () => {
+    mockCreate.mockResolvedValueOnce(buildResp(2))
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 2, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.ready).toBe(true))
+    const arg = mockCreate.mock.calls[0][0]
+    expect(arg).not.toHaveProperty("source_edit_plan_id")
+  })
+
+  it("404（后端端点未上线）→ error=true，不再静默降级", async () => {
+    mockCreate.mockRejectedValueOnce({ response: { status: 404 } })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 3, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(result.current.error).toBe(true)
+    expect(result.current.ready).toBe(false)
+    expect(result.current.clipsByVariant).toEqual([])
+  })
+
+  it("400（参数错误）→ error=true", async () => {
+    mockCreate.mockRejectedValueOnce({ response: { status: 400, data: { detail: "参数错误" } } })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 3, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(result.current.error).toBe(true)
+    expect(result.current.ready).toBe(false)
+  })
+
+  it("网络错误 → error=true", async () => {
+    mockCreate.mockRejectedValue(new Error("Network Error"))
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 3, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(result.current.error).toBe(true)
+    expect(result.current.ready).toBe(false)
+  })
+
+  it("某变体 clips 为空（数据不完整）→ error=true，严禁假数据冒充", async () => {
+    mockCreate.mockResolvedValueOnce({
+      total: 2,
+      items: [
+        { variant_index: 0, plan_id: "plan-0", clips: [makeClip({ asset_id: "a1", order: 0 })] },
+        { variant_index: 1, plan_id: "plan-1", clips: [] },
+      ],
+    })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 2, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(result.current.error).toBe(true)
+    expect(result.current.ready).toBe(false)
+    expect(result.current.clipsByVariant).toEqual([])
+  })
+
+  it("retry() 失败后重试：成功则 error 清除、ready=true", async () => {
+    mockCreate.mockRejectedValueOnce({ response: { status: 404 } })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 3, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.error).toBe(true))
+
+    mockCreate.mockResolvedValueOnce(buildResp(3))
+    act(() => {
+      result.current.retry()
+    })
+    await waitFor(() => expect(result.current.ready).toBe(true))
+    expect(result.current.error).toBe(false)
+    expect(mockCreate).toHaveBeenCalledTimes(2)
+  })
+
+  it("N=1 不发请求（单视频零回归）", () => {
+    renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 1, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    expect(mockCreate).not.toHaveBeenCalled()
+  })
+
+  it("无素材/enabled=false 不发请求", () => {
+    const { rerender } = renderHook(
+      (props: { enabled: boolean; ids: string[] }) =>
+        useBatchVariantPlans({
+          enabled: props.enabled,
+          count: 3,
+          templateId: "tpl-1",
+          assetIds: props.ids,
+        }),
+      { initialProps: { enabled: true, ids: [] as string[] } },
+    )
+    expect(mockCreate).not.toHaveBeenCalled()
+    rerender({ enabled: false, ids: ["a1"] })
+    expect(mockCreate).not.toHaveBeenCalled()
+  })
+
+  it("响应乱序/越界 variant_index：越界丢弃、其余按索引对齐", async () => {
+    mockCreate.mockResolvedValueOnce({
+      total: 2,
+      items: [
+        { variant_index: 99, plan_id: "plan-bad", clips: [makeClip({ asset_id: "a9", order: 0 })] },
+        { variant_index: 1, plan_id: "plan-1", clips: [makeClip({ asset_id: "a2", order: 0 })] },
+        { variant_index: 0, plan_id: "plan-0", clips: [makeClip({ asset_id: "a1", order: 0 })] },
+      ],
+    })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({
+        enabled: true,
+        count: 2,
+        templateId: "tpl-1",
+        assetIds: ["a1", "a2"],
+      }),
+    )
+    await waitFor(() => expect(result.current.ready).toBe(true))
+    // 越界 99 丢弃；乱序返回的 0/1 按索引对齐
+    expect(result.current.error).toBe(false)
+    expect(result.current.planIdsByVariant).toEqual(["plan-0", "plan-1"])
+    expect(result.current.clipsByVariant[0]?.[0]?.asset_id).toBe("a1")
+    expect(result.current.clipsByVariant[1]?.[0]?.asset_id).toBe("a2")
+  })
+
+  it("非 ready 状态的 clip 被过滤；过滤后每变体仍有片段则 ready", async () => {
+    mockCreate.mockResolvedValueOnce({
+      total: 2,
+      items: [
+        {
+          variant_index: 0,
+          plan_id: "plan-0",
+          clips: [
+            makeClip({ asset_id: "a1", order: 0 }),
+            makeClip({ asset_id: "a2", order: 1, status: "pending" }),
+          ],
+        },
+        { variant_index: 1, plan_id: "plan-1", clips: [makeClip({ asset_id: "a3", order: 0 })] },
+      ],
+    })
+    const { result } = renderHook(() =>
+      useBatchVariantPlans({ enabled: true, count: 2, templateId: "tpl-1", assetIds: ["a1"] }),
+    )
+    await waitFor(() => expect(result.current.ready).toBe(true))
+    expect(result.current.error).toBe(false)
+    expect(result.current.clipsByVariant[0]).toHaveLength(1)
+    expect(result.current.clipsByVariant[0]?.[0]?.asset_id).toBe("a1")
+  })
+})

apps/worker/video_processing/dedup.py

@@ -7,6 +7,7 @@ import hashlib
 import logging
 import math
 import os
+import re
 import statistics
 import tempfile
 from dataclasses import dataclass, field
@@ -56,8 +57,13 @@ MAX_GAP = 2  # 允许的最大间隙帧数
 NEIGHBOR_WINDOW = 1  # 分片时序对齐：允许 ±1 邻接偏移（1s 密集采样下即 ±1s，缓解切点不一致）
 
 # ── 融合判定常量 ────────────────────────────────────────────────
-PHASH_WEIGHT = 0.7  # pHash 权重
-HISTOGRAM_WEIGHT = 0.3  # 直方图权重
+PHASH_WEIGHT = 0.7  # pHash 权重（视觉内部）
+HISTOGRAM_WEIGHT = 0.3  # 直方图权重（视觉内部）
+
+# ── 多维度查重融合权重（Issue #P2-后端3） ────────────────────────
+VISUAL_WEIGHT = 0.5  # 视觉相似度权重（pHash+直方图）
+TEXT_WEIGHT = 0.25  # 文案相似度权重（配音文本）
+STRUCTURE_WEIGHT = 0.25  # 结构相似度权重（片段序列）
 MATCH_RATIO_THRESHOLD = 0.7  # 全片重复（is_duplicate）至少 70% 帧匹配
 PARTIAL_COVERAGE_THRESHOLD = 0.5  # 局部复用覆盖率 >=50% 也判全片重复
 DUPLICATE_THRESHOLD = 0.70  # 融合后相似度阈值
@@ -1057,12 +1063,11 @@ class VideoDeduplicator:
     ) -> dict:
         """计算当前视频与已有视频的查重率百分比。
 
-        新公式（双指标加权）：
-        - frame_match_rate = 汉明距离 < PHASH_THRESHOLD 的帧数 / 总帧数
-        - temporal_coverage_rate = 连续匹配片段总时长 / 视频总时长
-        - duplicate_rate = (frame_match_rate * 0.4 + temporal_coverage_rate * 0.6) * 100
-
-        visual_similarity = 0.7 * phash_sim + 0.3 * hist_sim（归一化到 0~1）
+        多维度融合公式（Issue #P2-后端3）：
+        - visual_similarity = 0.7 * phash_sim + 0.3 * hist_sim（视觉维度）
+        - text_similarity = 文案 Jaccard 相似度（文案维度）
+        - structure_similarity = 片段序列相似度（结构维度）
+        - duplicate_rate = (visual*0.5 + text*0.25 + structure*0.25) * 100
 
         对每个匹配视频都算，取最高 duplicate_rate。
 
@@ -1093,6 +1098,29 @@ class VideoDeduplicator:
         match_count = 0
         evaluated = 0
 
+        # Issue #P2-后端3: 加载当前视频的文案+结构数据
+        from packages.adapters.sqlalchemy_impl.models import EditPlanClipModel, GeneratedVideoModel
+
+        current_video_obj = (
+            session.query(GeneratedVideoModel).filter(GeneratedVideoModel.id == current_video_id).first()
+            if current_video_id
+            else None
+        )
+        current_plan_id = getattr(current_video_obj, "edit_plan_id", "") or ""
+        current_clips_data = []
+        current_text_content = ""
+
+        if current_plan_id:
+            current_clips = (
+                session.query(EditPlanClipModel)
+                .filter(EditPlanClipModel.plan_id == current_plan_id)
+                .order_by(EditPlanClipModel.order)
+                .all()
+            )
+            current_clips_data = [{"clip_type": c.clip_type, "duration": c.duration} for c in current_clips]
+            # 拼接所有片段的文本内容
+            current_text_content = " ".join(c.text_content for c in current_clips if c.text_content)
+
         for existing in existing_videos:
             if current_video_id and existing.id == current_video_id:
                 continue
@@ -1160,8 +1188,47 @@ class VideoDeduplicator:
 
             # Issue #1702: 去掉 "frame_match_rate<0.3 整条跳过" 硬门槛——
             # 局部片段复用帧比例天然低；coverage 为主指标，0 匹配自然得 0 分。
-            # duplicate_rate = 0.4 * frame_match_rate + 0.6 * temporal_coverage
-            dup_rate = (min(ev["frame_match_rate"], 1.0) * 0.4 + ev["temporal_coverage"] * 0.6) * 100
+            # 视觉维度：0.4 * frame_match_rate + 0.6 * temporal_coverage
+            visual_sim = min(ev["frame_match_rate"], 1.0) * 0.4 + ev["temporal_coverage"] * 0.6
+
+            # Issue #P2-后端3: 文案+结构维度
+            existing_plan_id = getattr(existing, "edit_plan_id", "") or ""
+            existing_clips_data = []
+            existing_text_content = ""
+
+            if existing_plan_id:
+                existing_clips = (
+                    session.query(EditPlanClipModel)
+                    .filter(EditPlanClipModel.plan_id == existing_plan_id)
+                    .order_by(EditPlanClipModel.order)
+                    .all()
+                )
+                existing_clips_data = [{"clip_type": c.clip_type, "duration": c.duration} for c in existing_clips]
+                existing_text_content = " ".join(c.text_content for c in existing_clips if c.text_content)
+
+            # 计算文案相似度（有文案才算）
+            text_sim = (
+                compute_text_similarity(current_text_content, existing_text_content)
+                if (current_text_content and existing_text_content)
+                else 0.0
+            )
+
+            # 计算结构相似度（有片段才算）
+            structure_sim = (
+                compute_structure_similarity(current_clips_data, existing_clips_data)
+                if (current_clips_data and existing_clips_data)
+                else 0.0
+            )
+
+            # 多维度融合：visual*0.5 + text*0.25 + structure*0.25
+            # 如果文案/结构数据缺失，只用视觉维度（visual 权重提升到 1.0）
+            if current_text_content and existing_text_content and current_clips_data and existing_clips_data:
+                dup_rate = (
+                    visual_sim * VISUAL_WEIGHT + text_sim * TEXT_WEIGHT + structure_sim * STRUCTURE_WEIGHT
+                ) * 100
+            else:
+                # 降级：只有视觉维度
+                dup_rate = visual_sim * 100
 
             # 全片重复计数与 check_duplicate 判定口径一致
             if ev["fusion"] >= DUPLICATE_THRESHOLD and (
@@ -1190,6 +1257,110 @@ class VideoDeduplicator:
         }
 
 
+# ── 文案 & 结构维度查重（Issue #P2-后端3） ────────────────────────
+
+
+def _normalize_text(text: str) -> str:
+    """文本标准化：去空白、转小写、去标点。"""
+    if not text:
+        return ""
+    # 去空白字符
+    text = re.sub(r"\s+", "", text)
+    # 转小写
+    text = text.lower()
+    # 去标点（只保留中文、字母、数字）
+    text = re.sub(r"[^\w\u4e00-\u9fff]", "", text)
+    return text
+
+
+def compute_text_similarity(text1: str, text2: str) -> float:
+    """计算两段文本的相似度（0~1）。
+
+    使用字符级 Jaccard 相似度：交集 / 并集。
+    适合短文本（配音脚本）的相似度比对。
+
+    Args:
+        text1: 第一段文本
+        text2: 第二段文本
+
+    Returns:
+        0~1 之间的相似度
+    """
+    t1 = _normalize_text(text1)
+    t2 = _normalize_text(text2)
+
+    if not t1 and not t2:
+        return 1.0  # 都为空，视为完全相同
+    if not t1 or not t2:
+        return 0.0  # 一个为空，完全不同
+
+    # 字符级 Jaccard
+    set1 = set(t1)
+    set2 = set(t2)
+    intersection = set1 & set2
+    union = set1 | set2
+
+    if not union:
+        return 0.0
+
+    return len(intersection) / len(union)
+
+
+def compute_structure_similarity(clips1: list[dict], clips2: list[dict]) -> float:
+    """计算两个视频的结构相似度（0~1）。
+
+    结构维度包括：
+    1. 片段数差异（数量越接近越相似）
+    2. 片段类型序列（相同位置的片段类型是否一致）
+    3. 时长分布（各片段时长占比是否相似）
+
+    Args:
+        clips1: 第一个视频的片段列表，每项包含 {clip_type, duration}
+        clips2: 第二个视频的片段列表
+
+    Returns:
+        0~1 之间的相似度
+    """
+    if not clips1 and not clips2:
+        return 1.0
+    if not clips1 or not clips2:
+        return 0.0
+
+    # 1. 片段数相似度（数量差异越大越低）
+    n1, n2 = len(clips1), len(clips2)
+    count_sim = min(n1, n2) / max(n1, n2)
+
+    # 2. 类型序列相似度（逐位比较，相同位置类型是否一致）
+    min_len = min(n1, n2)
+    type_matches = sum(1 for i in range(min_len) if clips1[i].get("clip_type") == clips2[i].get("clip_type"))
+    type_sim = type_matches / min_len if min_len > 0 else 0.0
+
+    # 3. 时长分布相似度（归一化后比较分布）
+    total1 = sum(c.get("duration", 0) for c in clips1)
+    total2 = sum(c.get("duration", 0) for c in clips2)
+
+    if total1 > 0 and total2 > 0:
+        # 归一化为占比
+        dist1 = [c.get("duration", 0) / total1 for c in clips1]
+        dist2 = [c.get("duration", 0) / total2 for c in clips2]
+
+        # 比较前 min_len 个片段的占比差异（L1 距离转相似度）
+        l1_dist = sum(abs(dist1[i] - dist2[i]) for i in range(min_len))
+        # 加上多出的片段占比
+        if n1 > n2:
+            l1_dist += sum(dist1[i] for i in range(n2, n1))
+        elif n2 > n1:
+            l1_dist += sum(dist2[i] for i in range(n1, n2))
+
+        # L1 距离范围 [0, 2]，转为相似度 [0, 1]
+        duration_sim = 1.0 - (l1_dist / 2.0)
+    else:
+        duration_sim = 0.0
+
+    # 三维度加权：数量 0.3 + 类型 0.4 + 时长 0.3
+    return count_sim * 0.3 + type_sim * 0.4 + duration_sim * 0.3
+
+
 def _save_fingerprint_chunks(
     fingerprint: VideoFingerprint,
     video_id: str,

apps/worker/video_processing/dedup_helpers.py

@@ -34,7 +34,9 @@ def create_video_record_and_dedup(
     fps: float = 25.0,
     name: str = "",
     thumbnail_url: str = "",
-) -> int:
+) -> dict:
+    """Returns: {"video_count": int, "is_duplicate": bool, "batch_similarity": float|None,
+    "duplicate_of": str|None} —— batch_similarity 为批次内最高相似度（无批次查重时 None）。"""
     """创建 GeneratedVideo 记录，计算指纹并执行查重（历史 + 批次）。
 
     采用两阶段持久化：先计算所有指纹/查重数据（内存），
@@ -76,6 +78,7 @@ def create_video_record_and_dedup(
         # ── Phase 2: 计算指纹 & 查重（全部在内存） ────────────────
         deduplicator = VideoDeduplicator()
         fingerprint = None
+        batch_similarity: float | None = None
 
         try:
             fingerprint = deduplicator.compute_fingerprint(video_path)
@@ -105,9 +108,11 @@ def create_video_record_and_dedup(
             )
 
             # (b) 批次内查重（仅当有 batch_id 时）
+            batch_similarity: float | None = None
             if not duplicate_result and batch_id:
                 duplicate_result = deduplicator.check_batch_duplicate(fingerprint, batch_id, video_id, session)
-
+                if duplicate_result:
+                    batch_similarity = float(duplicate_result.get("similarity", 0.0))
             if duplicate_result:
                 generated_video.is_duplicate = True
                 generated_video.duplicate_of = duplicate_result["duplicate_of"]
@@ -161,7 +166,12 @@ def create_video_record_and_dedup(
             generated_video.is_duplicate,
             generated_video.duplicate_rate,
         )
-        return 1
+        return {
+            "video_count": 1,
+            "is_duplicate": bool(generated_video.is_duplicate),
+            "batch_similarity": batch_similarity,
+            "duplicate_of": generated_video.duplicate_of,
+        }
     except Exception as e:
         logger.error(
             "Failed to create video record / dedup for task %s: %s",
@@ -169,4 +179,4 @@ def create_video_record_and_dedup(
             e,
         )
         session.rollback()
-        return 0
+        return {"video_count": 0, "is_duplicate": False, "batch_similarity": None, "duplicate_of": None}

apps/worker/video_processing/ffmpeg_utils.py

@@ -16,6 +16,9 @@ from typing import Any
 from shared.ffmpeg_utils import (  # noqa: F401
     DEFAULT_FFMPEG_TIMEOUT,
     FFMPEG_BIN,
+    FFMPEG_ENCODE_CRF,
+    FFMPEG_ENCODE_PRESET,
+    FFMPEG_ENCODE_THREADS,
     FFPROBE_BIN,
     run_ffmpeg,
 )
@@ -291,9 +294,11 @@ def normalize_video(
         "-c:v",
         "libx264",
         "-crf",
-        "23",
+        FFMPEG_ENCODE_CRF,
         "-preset",
-        "medium",
+        FFMPEG_ENCODE_PRESET,
+        "-threads",
+        FFMPEG_ENCODE_THREADS,
         "-c:a",
         "aac",
         "-b:a",
@@ -404,9 +409,11 @@ def random_edge_crop(
         "-c:v",
         "libx264",
         "-preset",
-        "fast",
+        FFMPEG_ENCODE_PRESET,
         "-crf",
-        "18",
+        FFMPEG_ENCODE_CRF,
+        "-threads",
+        FFMPEG_ENCODE_THREADS,
         "-c:a",
         "copy",
         "-movflags",

apps/worker/video_processing/processor.py

@@ -9,6 +9,7 @@ from dataclasses import dataclass
 from typing import List
 
 import ffmpeg
+from shared.ffmpeg_utils import FFMPEG_ENCODE_CRF, FFMPEG_ENCODE_PRESET
 
 logger = logging.getLogger(__name__)
 
@@ -90,8 +91,8 @@ class VideoProcessor:
                     acodec="aac",
                     s=f"{width}x{height}",
                     r=fps,
-                    preset="medium",
-                    crf=23,
+                    preset=FFMPEG_ENCODE_PRESET,
+                    crf=int(FFMPEG_ENCODE_CRF),
                 )
                 .overwrite_output()
                 .run(capture_stdout=True, capture_stderr=True)

apps/worker/video_processing/render_adapter.py

@@ -599,7 +599,7 @@ class RenderAdapter:
             # 抽帧天然带标题，因此这里传空字符串，避免 Pillow 二次叠加导致重影。
             # Pillow 叠加仅用于 API 从源素材抽帧（源素材本身无标题）的兜底场景。
             cover_candidates = extract_and_upload_cover_frames(
-                str(result.output_path), plan_id, task_id=job_id, num_frames=3, title_text=""
+                str(result.output_path), plan_id, task_id=job_id, num_frames=5, title_text=""
             )
             if cover_candidates:
                 logger.info(

apps/worker/video_processing/render_audio.py

@@ -47,13 +47,23 @@ class RenderContext:
 
 
 def clip_effective_duration(clip: ResolvedClip) -> float:
-    """计算 clip 的有效时长.
+    """计算 clip 的有效时长（#1749：目标段长始终为准）。
 
-    与 UnifiedRenderService._clip_effective_duration 逻辑一致。
+    与 UnifiedRenderService._clip_effective_duration 逻辑一致；素材短于段长的
+    部分由末帧冻结 tpad / 音频 apad 铺满，不在此处钳制。
     """
     if clip.duration > 0:
-        return min(clip.duration, clip.actual_duration) if clip.actual_duration > 0 else clip.duration
-    return clip.actual_duration if clip.actual_duration > 0 else 0.0
+        return float(clip.duration)
+    return float(clip.actual_duration) if clip.actual_duration > 0 else 0.0
+
+
+def _clip_freeze_seconds(clip: ResolvedClip) -> float:
+    """读取 #1749 末帧冻结秒数（_resolve_clips 写入 config['_freeze_seconds']）。"""
+    cfg = getattr(clip, "config", None) or {}
+    try:
+        return max(0.0, float(cfg.get("_freeze_seconds", 0.0) or 0.0))
+    except (TypeError, ValueError):
+        return 0.0
 
 
 def clip_has_audio(ctx: RenderContext, clip: ResolvedClip) -> bool:
@@ -273,6 +283,9 @@ def concat_main_audio(
         if video_duration > 0 and (final_duration <= 0 or final_duration > video_duration):
             final_duration = video_duration
 
+        # #1749 末帧冻结秒数（音频需 apad 补静音与视频等长）
+        freeze_seconds = _clip_freeze_seconds(clip)
+
         # 音频倒放
         reverse_config = ReverseConfig.from_dict(clip.config.get("reverse"))
         has_reverse = reverse_config.enabled and reverse_config.reverse_audio
@@ -281,20 +294,28 @@ def concat_main_audio(
         if not has_speed and not has_reverse:
             # 无调速无倒放：根据是否需要裁剪/音量选择最高效的路径。
             vol = _clip_volume(clip)
-            need_trim = trim_start > 0 or (effective_duration > 0 and final_duration < adjusted_duration)
+            need_trim = (
+                trim_start > 0 or freeze_seconds > 0 or (effective_duration > 0 and final_duration < adjusted_duration)
+            )
             need_volume = abs(vol - 1.0) >= 1e-6
 
             if need_trim:
                 # 需要裁剪：用 atrim 滤镜在滤镜链中精确裁剪（采样点级精度，不浪费解码）。
-                # 滤镜顺序：atrim → asetpts → volume（先裁剪再调音量，避免处理被丢弃的数据）。
+                # 滤镜顺序：atrim → asetpts → apad(冻结补静音) → volume。
                 af_parts: list[str] = []
-                if trim_start > 0 and effective_duration > 0:
-                    af_parts.append(f"atrim=start={trim_start:.3f}:duration={final_duration:.3f}")
+                # 冻结场景：素材内可用时长 = 目标段长 − freeze（截掉超出素材的部分后补静音）
+                atrim_dur = final_duration
+                if freeze_seconds > 0:
+                    atrim_dur = max(0.0, final_duration - freeze_seconds)
+                if trim_start > 0 and atrim_dur > 0:
+                    af_parts.append(f"atrim=start={trim_start:.3f}:duration={atrim_dur:.3f}")
                 elif trim_start > 0:
                     af_parts.append(f"atrim=start={trim_start:.3f}")
-                elif final_duration > 0:
-                    af_parts.append(f"atrim=duration={final_duration:.3f}")
+                elif atrim_dur > 0:
+                    af_parts.append(f"atrim=duration={atrim_dur:.3f}")
                 af_parts.append("asetpts=PTS-STARTPTS")
+                if freeze_seconds > 0:
+                    af_parts.append(f"apad=whole_dur={final_duration:.3f}")
                 if need_volume:
                     af_parts.append(f"volume={vol:.4f}")
                 command = [
@@ -334,8 +355,13 @@ def concat_main_audio(
                     "-ac",
                     "2",
                 ]
+                af_simple: list[str] = []
                 if need_volume:
-                    command.extend(["-af", f"volume={vol:.4f}"])
+                    af_simple.append(f"volume={vol:.4f}")
+                if freeze_seconds > 0:
+                    af_simple.append(f"apad=whole_dur={final_duration:.3f}")
+                if af_simple:
+                    command.extend(["-af", ",".join(af_simple)])
                 if final_duration > 0:
                     command.extend(["-t", f"{final_duration:.3f}"])
                 command.append(str(output_path))
@@ -369,6 +395,10 @@ def concat_main_audio(
             if abs(vol - 1.0) >= 1e-6:
                 audio_filters.append(f"volume={vol:.4f}")
 
+            # #1749 冻结补静音（调速后时长已变，apad 补齐到最终时长）
+            if freeze_seconds > 0:
+                audio_filters.append(f"apad=whole_dur={final_duration:.3f}")
+
             # aformat 归一化：统一输出格式为 48000Hz + stereo + fltp
             audio_filters.append("aformat=sample_rates=48000:channel_layouts=stereo:sample_fmts=fltp")
 
@@ -410,10 +440,13 @@ def concat_main_audio(
         speed = getattr(clip, "playback_speed", 1.0) or 1.0
         if not isinstance(speed, (int, float)) or speed <= 0:
             speed = 1.0
+        # #1749 末帧冻结：素材内可用时长 = 目标段长 − freeze，apad 补静音
+        freeze_seconds = _clip_freeze_seconds(clip)
+        atrim_dur = max(0.0, effective_duration - freeze_seconds) if freeze_seconds > 0 else effective_duration
 
         audio_filters: list[str] = []
         if effective_duration > 0:
-            audio_filters.append(f"atrim=start={trim_start:.3f}:duration={effective_duration:.3f}")
+            audio_filters.append(f"atrim=start={trim_start:.3f}:duration={atrim_dur:.3f}")
             audio_filters.append("asetpts=PTS-STARTPTS")
 
         # 音频调速 — atempo 多级串联
@@ -435,6 +468,10 @@ def concat_main_audio(
             if reverse_filter:
                 audio_filters.append(reverse_filter)
 
+        # #1749 冻结补静音：视频 tpad 延长后音频等长补齐（concat 时间轴对齐）
+        if freeze_seconds > 0:
+            audio_filters.append(f"apad=whole_dur={effective_duration:.3f}")
+
         # 音量（0=静音，1=原声）
         vol = _clip_volume(clip)
         if abs(vol - 1.0) >= 1e-6:
@@ -506,12 +543,17 @@ def mix_with_independent_audio(
             input_args.extend(["-i", str(clip.local_path)])
             effective_duration = clip_effective_duration(clip)
             trim_start = getattr(clip, "start_time", 0) or 0
+            freeze_seconds = _clip_freeze_seconds(clip)
+            atrim_dur = max(0.0, effective_duration - freeze_seconds) if freeze_seconds > 0 else effective_duration
             clip_filters = []
             if effective_duration > 0:
-                clip_filters.append(f"atrim=start={trim_start:.3f}:duration={effective_duration:.3f}")
+                clip_filters.append(f"atrim=start={trim_start:.3f}:duration={atrim_dur:.3f}")
                 clip_filters.append("asetpts=PTS-STARTPTS")
             else:
                 clip_filters.append("asetpts=PTS-STARTPTS")
+            # #1749 冻结补静音（与视频 tpad 等长）
+            if freeze_seconds > 0:
+                clip_filters.append(f"apad=whole_dur={effective_duration:.3f}")
             vol = _clip_volume(clip)
             if abs(vol - 1.0) >= 1e-6:
                 clip_filters.append(f"volume={vol:.4f}")

apps/worker/video_processing/thumbnail_generator.py

@@ -279,21 +279,25 @@ def extract_and_upload_cover_frames(
     plan_id: str,
     *,
     task_id: str = "",
-    num_frames: int = 3,
+    num_frames: int = 5,  # 抽 5 帧候选，通过质量评分选出最佳帧
     title_text: str = "",
     title_color: str = "#ffffff",
     title_position: str = "bottom",
     title_font_size: int | None = None,
 ) -> list[dict]:
-    """从视频中抽取多帧作为封面候选，上传到 OSS。
+    """从视频中抽取多帧作为封面候选，通过质量评分选出最佳帧，上传到 OSS。
 
-    优先使用 MediaKit 智能抽帧，失败时降级到 ffmpeg 直接抽帧。
+    流程：
+    1. 优先使用 MediaKit 智能抽帧（多抽一些供选择）
+    2. MediaKit 不足时降级到 ffmpeg 均匀抽帧
+    3. 对所有候选帧进行质量评分（清晰度/亮度/色彩丰富度）
+    4. 按分数从高到低排序返回
 
     Args:
         video_path: 视频文件路径
         plan_id: 编辑计划 ID（用于生成 storage key）
         task_id: 任务 ID（用于生成独立的 storage key，避免标题变更时封面冲突）
-        num_frames: 抽取帧数（默认 3）
+        num_frames: 抽取候选帧数（默认 5，通过质量评分选出最佳帧）
         title_text: 标题文字；非空时用 Pillow 叠加到每帧。
             从已渲染视频抽帧时通常传空（标题已烧录）；从源素材抽帧时传标题。
         title_color: 标题字体颜色（#RRGGBB）
@@ -301,7 +305,7 @@ def extract_and_upload_cover_frames(
         title_font_size: 标题字号，None 时自动计算
 
     Returns:
-        封面候选列表，每项包含 {"url": str, "position": float}
+        封面候选列表（按质量分数降序），每项包含 {"url": str, "position": float, "score": float}
     """
     import httpx
     from video_processing.ffmpeg_utils import probe_duration
@@ -313,80 +317,125 @@ def extract_and_upload_cover_frames(
         duration = 0.0
 
     candidates: list[dict] = []
+    _temp_paths: list[str] = []  # 收集所有临时文件路径，最后统一清理
 
-    # 优先尝试 MediaKit 智能抽帧
-    mediakit_frames = _extract_frames_via_mediakit(video_path, plan_id, num_frames)
-    if mediakit_frames:
-        for i, frame in enumerate(mediakit_frames):
-            frame_url = frame.get("image_url")
-            if not frame_url:
-                continue
-            tmp = tempfile.NamedTemporaryFile(suffix=".jpg", delete=False)
-            tmp.close()
-            try:
-                # 下载 MediaKit 返回的帧图
-                resp = httpx.get(frame_url, timeout=30, follow_redirects=True)
-                resp.raise_for_status()
-                with open(tmp.name, "wb") as f:
-                    f.write(resp.content)
+    try:
+        # ── 阶段 1：抽帧 ──────────────────────────────────────────────
+        # 优先尝试 MediaKit 智能抽帧
+        mediakit_frames = _extract_frames_via_mediakit(video_path, plan_id, num_frames)
+        if mediakit_frames:
+            for i, frame in enumerate(mediakit_frames):
+                frame_url = frame.get("image_url")
+                if not frame_url:
+                    continue
+                tmp = tempfile.NamedTemporaryFile(suffix=".jpg", delete=False)
+                tmp.close()
+                _temp_paths.append(tmp.name)
+                try:
+                    # 下载 MediaKit 返回的帧图
+                    resp = httpx.get(frame_url, timeout=30, follow_redirects=True)
+                    resp.raise_for_status()
+                    with open(tmp.name, "wb") as f:
+                        f.write(resp.content)
 
-                # 叠加标题文字（如需要）
-                if title_text and title_text.strip():
-                    apply_title_overlay(
-                        tmp.name,
-                        title_text,
-                        color=title_color,
-                        position=title_position,
-                        font_size=title_font_size,
+                    # 叠加标题文字（如需要）
+                    if title_text and title_text.strip():
+                        apply_title_overlay(
+                            tmp.name,
+                            title_text,
+                            color=title_color,
+                            position=title_position,
+                            font_size=title_font_size,
+                        )
+
+                    storage_key = f"covers/{plan_id}/{task_id}/mediakit_frame_{i}.jpg"
+                    url = upload_to_oss(tmp.name, storage_key)
+                    if url:
+                        seek_time = frame.get("timestamp", 0.0)
+                        candidates.append(
+                            {
+                                "url": url,
+                                "position": round(seek_time, 2),
+                                "image_path": tmp.name,
+                            }
+                        )
+                except Exception as e:
+                    logger.warning("[thumbnail] MediaKit 帧 %d 处理失败: %s", i, e)
+
+            if len(candidates) >= num_frames:
+                logger.info("[thumbnail] MediaKit 智能抽帧完成: %d 帧", len(candidates))
+            else:
+                logger.warning("[thumbnail] MediaKit 抽帧不足 %d 帧，降级到 ffmpeg", num_frames)
+
+        # Fallback: ffmpeg 直接抽帧（仅当 MediaKit 不足时）
+        if len(candidates) < num_frames:
+            logger.info("[thumbnail] 使用 ffmpeg 抽帧补充")
+            # 均匀分布抽帧点：从 10% 到 90%
+            for i in range(num_frames):
+                ratio = 0.1 + 0.8 * i / max(num_frames - 1, 1)
+                tmp = tempfile.NamedTemporaryFile(suffix=".jpg", delete=False)
+                tmp.close()
+                _temp_paths.append(tmp.name)
+                try:
+                    frame_path = extract_first_frame(
+                        video_path,
+                        output_path=tmp.name,
+                        seek_ratio=ratio,
+                        min_seek_seconds=0.5,
                     )
+                    # 从源素材抽帧时叠加标题文字；已渲染视频标题已烧录时传空字符串跳过
+                    if title_text and title_text.strip():
+                        apply_title_overlay(
+                            frame_path,
+                            title_text,
+                            color=title_color,
+                            position=title_position,
+                            font_size=title_font_size,
+                        )
+                    storage_key = f"covers/{plan_id}/{task_id}/frame_{i}.jpg"
+                    url = upload_to_oss(frame_path, storage_key)
+                    if url:
+                        seek_time = max(0.5, duration * ratio) if duration > 0 else 0.0
+                        candidates.append(
+                            {
+                                "url": url,
+                                "position": round(seek_time, 2),
+                                "image_path": tmp.name,
+                            }
+                        )
+                except Exception as e:
+                    logger.warning("[thumbnail] 封面候选帧 %d 提取失败: %s", i, e)
 
-                storage_key = f"covers/{plan_id}/{task_id}/mediakit_frame_{i}.jpg"
-                url = upload_to_oss(tmp.name, storage_key)
-                if url:
-                    seek_time = frame.get("timestamp", 0.0)
-                    candidates.append({"url": url, "position": round(seek_time, 2)})
-            except Exception as e:
-                logger.warning("[thumbnail] MediaKit 帧 %d 处理失败: %s", i, e)
-            finally:
-                Path(tmp.name).unlink(missing_ok=True)
+        # ── 阶段 2：质量评分 ────────────────────────────────────────────
+        if len(candidates) > 1:
+            try:
+                from packages.shared.cover_frame_scorer import score_frames
 
-        if len(candidates) >= num_frames:
-            logger.info("[thumbnail] MediaKit 智能抽帧完成: %d 帧", len(candidates))
-            return candidates[:num_frames]
-
-        logger.warning("[thumbnail] MediaKit 抽帧不足 %d 帧，降级到 ffmpeg", num_frames)
-
-    # Fallback: ffmpeg 直接抽帧
-    logger.info("[thumbnail] 使用 ffmpeg 抽帧")
-    # 均匀分布抽帧点：从 10% 到 90%
-    for i in range(num_frames):
-        ratio = 0.1 + 0.8 * i / max(num_frames - 1, 1)
-        tmp = tempfile.NamedTemporaryFile(suffix=".jpg", delete=False)
-        tmp.close()
-        try:
-            frame_path = extract_first_frame(
-                video_path,
-                output_path=tmp.name,
-                seek_ratio=ratio,
-                min_seek_seconds=0.5,
-            )
-            # 从源素材抽帧时叠加标题文字；已渲染视频标题已烧录时传空字符串跳过
-            if title_text and title_text.strip():
-                apply_title_overlay(
-                    frame_path,
-                    title_text,
-                    color=title_color,
-                    position=title_position,
-                    font_size=title_font_size,
+                candidates = score_frames(candidates)
+                logger.info(
+                    "[thumbnail] 封面帧质量评分完成: plan_id=%s count=%d best_score=%.1f",
+                    plan_id,
+                    len(candidates),
+                    candidates[0].get("score", 0.0) if candidates else 0.0,
+                )
+            except Exception:
+                logger.warning(
+                    "[thumbnail] 封面帧质量评分失败，保持原始顺序: plan_id=%s",
+                    plan_id,
+                    exc_info=True,
                 )
-            storage_key = f"covers/{plan_id}/{task_id}/frame_{i}.jpg"
-            url = upload_to_oss(frame_path, storage_key)
-            if url:
-                seek_time = max(0.5, duration * ratio) if duration > 0 else 0.0
-                candidates.append({"url": url, "position": round(seek_time, 2)})
-        except Exception as e:
-            logger.warning("[thumbnail] 封面候选帧 %d 提取失败: %s", i, e)
-        finally:
-            Path(tmp.name).unlink(missing_ok=True)
 
-    return candidates
+        # ── 阶段 3：清理临时文件 ────────────────────────────────────────
+        # 移除 image_path（不再需要），但临时文件统一清理
+        for c in candidates:
+            c.pop("image_path", None)
+
+        return candidates
+
+    finally:
+        # 统一清理所有临时文件
+        for path in _temp_paths:
+            try:
+                Path(path).unlink(missing_ok=True)
+            except Exception:
+                pass

apps/worker/video_processing/unified_render_service.py

@@ -35,6 +35,9 @@ from video_processing.ffmpeg_utils import (
     DEFAULT_OUTPUT_WIDTH,
     DEFAULT_TRANSITION_DURATION,
     FFMPEG_BIN,
+    FFMPEG_ENCODE_CRF,
+    FFMPEG_ENCODE_PRESET,
+    FFMPEG_ENCODE_THREADS,
     probe_duration,
     probe_has_audio,
     probe_video_info,
@@ -518,120 +521,45 @@ class UnifiedRenderService:
         layers: list[RenderLayer],
         voice_duration: float,
     ) -> None:
-        """调整片段时长以对齐配音时长。
+        """#1749：配音对齐仅保留 ±5% 守卫日志，不再做全局裁剪/慢放。
 
-        核心逻辑：
-        - 计算片段总时长与配音时长的比例
-        - ±5% 以内不调整
-        - ratio < 1（片段比配音长）：按比例裁剪每段末尾
-        - ratio > 1（片段比配音短）：按比例慢放每段
-
-        Args:
-            layers: 渲染图层列表
-            voice_duration: 配音时长（秒）
+        段长已在选片阶段由 voice_duration_planner 按配音时长精确分配
+        （成片总时长=配音，素材不足走末帧冻结 tpad/apad）。渲染期任何全局
+        裁剪会截断配音、全局慢放会导致失真——两者均已删除。此处仅在偏差
+        超阈值时记录 warning 供排查，不修改任何 clip。
         """
         if voice_duration <= 0:
             return
 
-        # 只调整视频图层（main/broll/background），不调整音频图层
         video_layers = [layer for layer in layers if layer.role in ("main", "broll", "background")]
         if not video_layers:
             return
 
-        # 计算所有视频图层的总时长
         total_clips_duration = 0.0
         for layer in video_layers:
             for clip in layer.clips:
-                clip_dur = self._clip_adjusted_duration(clip)
-                total_clips_duration += clip_dur
-
+                total_clips_duration += self._clip_adjusted_duration(clip)
         if total_clips_duration <= 0:
             return
 
-        ratio = voice_duration / total_clips_duration
-
-        # ±5% 以内不调整
-        if abs(ratio - 1.0) <= 0.05:
-            logger.info(
-                "[voice-align] 比例接近1:1，跳过调整: ratio=%.4f voice=%.3f clips=%.3f",
+        estimated = self._estimate_total_duration(video_layers)
+        ratio = voice_duration / total_clips_duration if total_clips_duration > 0 else 1.0
+        if abs(ratio - 1.0) > 0.05:
+            logger.warning(
+                "[voice-align] 段长合计与配音偏差>5%%（仅守卫，不裁剪/不慢放）: "
+                "ratio=%.4f voice=%.3f clips_sum=%.3f estimated_final=%.3f",
                 ratio,
                 voice_duration,
                 total_clips_duration,
+                estimated,
             )
-            return
-
-        logger.info(
-            "[voice-align] 开始调整片段时长: ratio=%.4f voice=%.3f clips=%.3f",
-            ratio,
-            voice_duration,
-            total_clips_duration,
-        )
-
-        # 收集所有视频 clip
-        all_clips: list[tuple[RenderLayer, ResolvedClip]] = []
-        for layer in video_layers:
-            for clip in layer.clips:
-                all_clips.append((layer, clip))
-
-        if not all_clips:
-            return
-
-        if ratio < 1.0:
-            # 片段比配音长，按比例裁剪每段末尾
-            # 减少每个 clip 的 duration
-            for _layer, clip in all_clips:
-                old_duration = clip.duration if clip.duration > 0 else clip.actual_duration
-                new_duration = old_duration * ratio
-
-                # 更新 duration
-                clip.duration = max(0.1, new_duration)  # 至少 0.1s
-
-                # 如果有 trim_config，也需要调整
-                if clip.trim_config is not None:
-                    new_trim_duration = clip.trim_config.duration * ratio
-                    clip.trim_config = TrimConfig(
-                        start_time=clip.trim_config.start_time,
-                        duration=max(0.1, new_trim_duration),
-                    )
-
-                logger.debug(
-                    "[voice-align] trim clip=%s: %.3f -> %.3f",
-                    clip.clip_id,
-                    old_duration,
-                    clip.duration,
-                )
-
         else:
-            # ratio > 1.0: 片段比配音短，按比例慢放每段
-            # 降低 playback_speed
-            for _layer, clip in all_clips:
-                old_speed = clip.playback_speed if clip.playback_speed > 0 else 1.0
-                # speed = old_speed / ratio 会使视频变慢（ratio > 1 时）
-                new_speed = old_speed / ratio
-
-                # 下限 0.25x（避免过慢）
-                new_speed = max(0.25, round(new_speed, 4))
-                clip.playback_speed = new_speed
-
-                logger.debug(
-                    "[voice-align] slowdown clip=%s: speed %.4f -> %.4f",
-                    clip.clip_id,
-                    old_speed,
-                    new_speed,
-                )
-
-        # 调整后重新计算总时长用于日志
-        new_total = 0.0
-        for layer in video_layers:
-            for clip in layer.clips:
-                new_total += self._clip_adjusted_duration(clip)
-
-        logger.info(
-            "[voice-align] 调整完成: 新总时长=%.3fs (目标=%.3fs, 差异=%.3fs)",
-            new_total,
-            voice_duration,
-            abs(new_total - voice_duration),
-        )
+            logger.info(
+                "[voice-align] 段长与配音偏差≤5%%，无需处理: ratio=%.4f voice=%.3f estimated=%.3f",
+                ratio,
+                voice_duration,
+                estimated,
+            )
 
     def _maybe_generate_ass(self, video_duration: float) -> Path | None:
         """根据 plan.config 生成 ASS 字幕文件。
@@ -1372,15 +1300,26 @@ class UnifiedRenderService:
 
         # trim
         effective_duration = UnifiedRenderService._clip_effective_duration(clip)
+        freeze_seconds = float((clip.config or {}).get("_freeze_seconds", 0.0) or 0.0)
+        # #1749 冻结时素材内截取时长 = 目标段长 − freeze
+        trim_dur = max(0.0, effective_duration - freeze_seconds) if freeze_seconds > 0 else effective_duration
 
-        if effective_duration > 0:
-            filters.append(f"trim=duration={effective_duration}")
+        if trim_dur > 0:
+            filters.append(f"trim=duration={trim_dur}")
             filters.append("setpts=PTS-STARTPTS")
+        # #1749 末帧冻结（禁慢放）
+        if freeze_seconds > 0:
+            filters.append(f"tpad=stop_mode=clone:stop_duration={freeze_seconds:.3f}")
 
-        # 调速 — 与 filter_complex 路径一致
+        # 视觉扰动（plan 级别，直通模式同样适用）
+        vp = self._get_visual_perturbation()
+
+        # 调速 — 与 filter_complex 路径一致（叠加视觉扰动 speed_factor）
         speed = UnifiedRenderService._clip_speed(clip)
-        if abs(speed - 1.0) >= 1e-6:
-            filters.append(f"setpts=PTS/{speed:.4f}")
+        vp_speed = vp.get("speed_factor", 1.0) if vp else 1.0
+        effective_speed = speed * vp_speed
+        if abs(effective_speed - 1.0) >= 1e-6:
+            filters.append(f"setpts=PTS/{effective_speed:.4f}")
 
         # 倒放滤镜
         reverse_config = ReverseConfig.from_dict(clip.config.get("reverse"))
@@ -1389,6 +1328,10 @@ class UnifiedRenderService:
             if reverse_filter:
                 filters.append(reverse_filter)
 
+        # 视觉扰动：hflip（在 scale 之前）
+        if vp:
+            self._apply_visual_perturbation_pre_scale(filters, vp)
+
         # scale + pad（等比缩放+留黑边）
         if role in ("overlay", "corner_voice"):
             pip_w = int(self.output_width * _PIP_SCALE)
@@ -1403,6 +1346,10 @@ class UnifiedRenderService:
             filters.append(f"scale={self.output_width}:{self.output_height}:force_original_aspect_ratio=decrease")
             filters.append(f"pad={self.output_width}:{self.output_height}:trunc((ow-iw)/2):trunc((oh-ih)/2):black")
 
+        # 视觉扰动：zoom + brightness（在 scale+pad 之后、调色之前）
+        if vp:
+            self._apply_visual_perturbation_post_scale(filters, vp)
+
         # 调色滤镜
         color_grade = ColorGradeConfig.from_dict(clip.config.get("color_grade"))
         if color_grade.enabled and color_grade.has_effect():
@@ -1424,6 +1371,10 @@ class UnifiedRenderService:
 
         filters.append("setpts=PTS-STARTPTS")
         filters.append(f"fps={self.output_fps}")
+        # #1749 末帧冻结：素材短于目标段长时克隆末帧铺满（禁慢放）
+        freeze_seconds = float((clip.config or {}).get("_freeze_seconds", 0.0) or 0.0)
+        if freeze_seconds > 0:
+            filters.append(f"tpad=stop_mode=clone:stop_duration={freeze_seconds:.3f}")
         filters.append("format=yuv420p")
 
         # 字幕叠加
@@ -1450,9 +1401,11 @@ class UnifiedRenderService:
             "-c:v",
             "libx264",
             "-crf",
-            "23",
+            FFMPEG_ENCODE_CRF,
             "-preset",
-            "medium",
+            FFMPEG_ENCODE_PRESET,
+            "-threads",
+            FFMPEG_ENCODE_THREADS,
             "-pix_fmt",
             "yuv420p",
             "-movflags",
@@ -1515,6 +1468,10 @@ class UnifiedRenderService:
             if abs(clip_volume - 1.0) >= 1e-6:
                 af_parts.append(f"volume={clip_volume:.4f}")
 
+            # #1749 音频冻结：视频 tpad 延长后音频需等长补静音，否则时间轴错位
+            if freeze_seconds > 0:
+                af_parts.append(f"apad=whole_dur={final_duration:.3f}")
+
             if af_parts:
                 command.extend(["-af", ",".join(af_parts)])
 
@@ -1624,7 +1581,9 @@ class UnifiedRenderService:
                 continue
 
             # 单段裁剪（或无裁剪）
-            # 解析裁剪配置：config 优先，否则用 clip.start_time + clip.duration
+            # #1749 定稿：目标段长（clip.duration，配音分配结果）始终为准。
+            # trim 只决定素材内截取区间；素材短于段长 → 末帧冻结（tpad）/音频补静音（apad）
+            # 铺满，禁止慢放、禁止截断配音。
             trim_config = extract_trim_from_clip_config(clip_config)
             if trim_config is None and (clip.start_time > 0 or clip.duration > 0):
                 # 用旧字段构造
@@ -1633,42 +1592,48 @@ class UnifiedRenderService:
                     duration=clip.duration,
                 )
 
-            # 钳制到实际素材时长
             effective_trim: TrimConfig | None = None
+            # 目标段长：配音分配后的 clip.duration 始终为准（不被素材时长钳制）
+            target_duration = float(clip.duration or 0.0)
             final_start = clip.start_time
-            final_duration = clip.duration
+            final_duration = target_duration
             configured_speed = getattr(clip, "playback_speed", 1.0) or 1.0
+            freeze_seconds = 0.0
 
             if trim_config is not None and actual_duration > 0:
-                effective_trim = trim_config.validate_and_resolve(actual_duration)
-                if effective_trim.is_valid:
-                    final_start = effective_trim.start_time
-                    final_duration = effective_trim.duration
+                resolved_trim = trim_config.validate_and_resolve(actual_duration)
+                if resolved_trim.is_valid:
+                    # trim 仅决定素材内截取区间 [start, min(start+dur, actual)]
+                    final_start = resolved_trim.start_time
+                    avail_in_asset = max(0.0, actual_duration - final_start)
+                    effective_trim = TrimConfig(
+                        start_time=final_start, duration=min(resolved_trim.duration, avail_in_asset)
+                    )
                 else:
-                    # 裁剪无效 → 使用完整素材
-                    logger.warning("裁剪配置无效，使用完整素材: clip_id=%s", clip.id)
-                    effective_trim = None
+                    # 裁剪无效 → 从素材头取
+                    logger.warning("裁剪配置无效，使用素材起点: clip_id=%s", clip.id)
                     final_start = 0.0
-                    final_duration = actual_duration
-
-            # 素材实际时长不足以覆盖配置的时长时，降低播放速度来补偿
-            # 例如：配置4s但素材只有3s → speed=0.75x，用满3s素材达到4s输出
-            if actual_duration > 0 and final_duration > actual_duration + 0.05:
-                compensated_speed = actual_duration / final_duration
-                # 保留用户设置的速度（如果已减速则叠加）
-                final_speed = configured_speed * compensated_speed
-                # 下限 0.25x
-                final_speed = max(0.25, round(final_speed, 4))
-                logger.info(
-                    "[debug] clip=%s duration=%.3f actual=%.3f → 减速补偿 speed=%.4f (configured=%.3f)",
-                    clip.id,
-                    final_duration,
-                    actual_duration,
-                    final_speed,
-                    configured_speed,
-                )
+                    avail_in_asset = actual_duration
             else:
-                final_speed = configured_speed
+                final_start = 0.0
+                avail_in_asset = actual_duration if actual_duration > 0 else target_duration
+
+            # 素材内可用时长不足目标段长 → 末帧冻结（禁慢放）
+            if target_duration > 0 and avail_in_asset < target_duration - 0.05:
+                freeze_seconds = round(target_duration - avail_in_asset, 3)
+                logger.info(
+                    "[freeze] clip=%s target=%.3f avail=%.3f → 末帧冻结 %.3fs（禁慢放）",
+                    clip.id,
+                    target_duration,
+                    avail_in_asset,
+                    freeze_seconds,
+                )
+            final_speed = configured_speed
+
+            # freeze 标记写入 config，供视频 tpad / 音频 apad 读取
+            resolved_config = dict(clip_config)
+            if freeze_seconds > 0:
+                resolved_config["_freeze_seconds"] = freeze_seconds
 
             rc = ResolvedClip(
                 clip_id=clip.id,
@@ -1681,7 +1646,7 @@ class UnifiedRenderService:
                 transition_effect=clip.transition_effect or "cut",
                 transition_duration=getattr(clip, "transition_duration", 0.0) or 0.0,
                 playback_speed=final_speed,
-                config=clip_config,
+                config=resolved_config,
                 actual_duration=actual_duration,
                 trim_config=effective_trim,
             )
@@ -1690,13 +1655,14 @@ class UnifiedRenderService:
             # Debug日志：记录每个clip的时长信息
             eff_dur = _clip_effective_duration_pure(final_duration, actual_duration)
             logger.info(
-                "[debug] resolved clip=%s duration=%.3f actual=%.3f effective=%.3f speed=%.4f start=%.3f",
+                "[debug] resolved clip=%s duration=%.3f actual=%.3f effective=%.3f speed=%.4f start=%.3f freeze=%.3f",
                 clip.id,
                 final_duration,
                 actual_duration,
                 eff_dur,
                 final_speed,
                 final_start,
+                freeze_seconds,
             )
 
         # 按 order 排序
@@ -1781,6 +1747,8 @@ class UnifiedRenderService:
         # Step 1: 预处理每个 clip — trim + scale + setpts
         # 为每个 clip 生成预处理后的标签 [v0], [v1], ...
         preprocessed_labels: list[str] = []
+        # 视觉扰动（plan 级别，所有 clip 共享同一套扰动参数）
+        vp = self._get_visual_perturbation()
         for i, clip in enumerate(all_clips):
             label = f"v{i}"
             role = _resolve_layer_role(clip.clip_type, clip.config)
@@ -1790,18 +1758,23 @@ class UnifiedRenderService:
             # trim — 裁剪到指定区间，精确到帧
             effective_duration = UnifiedRenderService._clip_effective_duration(clip)
             trim_start = getattr(clip, "start_time", 0) or 0
+            # #1749 冻结时素材内截取时长 = 目标段长 − freeze（末帧冻结由 tpad 铺满，与直通路径同口径）
+            freeze_seconds = float((clip.config or {}).get("_freeze_seconds", 0.0) or 0.0)
+            trim_dur = max(0.0, effective_duration - freeze_seconds) if freeze_seconds > 0 else effective_duration
 
-            if effective_duration > 0:
+            if trim_dur > 0:
                 if trim_start > 0:
-                    filters.append(f"trim=start={trim_start:.3f}:duration={effective_duration:.3f}")
+                    filters.append(f"trim=start={trim_start:.3f}:duration={trim_dur:.3f}")
                 else:
-                    filters.append(f"trim=duration={effective_duration:.3f}")
+                    filters.append(f"trim=duration={trim_dur:.3f}")
                 filters.append("setpts=PTS-STARTPTS")
 
-            # 调速 — 基于 setpts 改变播放速度
+            # 调速 — 基于 setpts 改变播放速度（叠加视觉扰动 speed_factor）
             speed = UnifiedRenderService._clip_speed(clip)
-            if abs(speed - 1.0) >= 1e-6:
-                filters.append(f"setpts=PTS/{speed:.4f}")
+            vp_speed = vp.get("speed_factor", 1.0) if vp else 1.0
+            effective_speed = speed * vp_speed
+            if abs(effective_speed - 1.0) >= 1e-6:
+                filters.append(f"setpts=PTS/{effective_speed:.4f}")
 
             # 倒放滤镜（在 trim 之后、scale 之前应用）
             reverse_config = ReverseConfig.from_dict(clip.config.get("reverse"))
@@ -1810,6 +1783,10 @@ class UnifiedRenderService:
                 if reverse_filter:
                     filters.append(reverse_filter)
 
+            # 视觉扰动：hflip（在 scale 之前，翻转原始画面）
+            if vp:
+                self._apply_visual_perturbation_pre_scale(filters, vp)
+
             # scale
             if role in ("overlay", "corner_voice"):
                 pip_w = int(self.output_width * _PIP_SCALE)
@@ -1824,6 +1801,10 @@ class UnifiedRenderService:
                 filters.append(f"scale={self.output_width}:{self.output_height}:force_original_aspect_ratio=decrease")
                 filters.append(f"pad={self.output_width}:{self.output_height}:trunc((ow-iw)/2):trunc((oh-ih)/2):black")
 
+            # 视觉扰动：zoom + brightness（在 scale+pad 之后、调色之前）
+            if vp:
+                self._apply_visual_perturbation_post_scale(filters, vp)
+
             # 调色滤镜（每个 clip 独立的 color grade 配置）
             color_grade = ColorGradeConfig.from_dict(clip.config.get("color_grade"))
             if color_grade.enabled and color_grade.has_effect():
@@ -1846,6 +1827,9 @@ class UnifiedRenderService:
 
             filters.append("setpts=PTS-STARTPTS")
             filters.append(f"fps={self.output_fps}")
+            # #1749 末帧冻结：素材短于目标段长时克隆末帧铺满（禁慢放）
+            if freeze_seconds > 0:
+                filters.append(f"tpad=stop_mode=clone:stop_duration={freeze_seconds:.3f}")
 
             filter_str = f"[{i}:v]{','.join(filters)}[{label}]"
             filter_parts.append(filter_str)
@@ -2046,9 +2030,11 @@ class UnifiedRenderService:
             "-c:v",
             "libx264",
             "-crf",
-            "23",
+            FFMPEG_ENCODE_CRF,
             "-preset",
-            "medium",
+            FFMPEG_ENCODE_PRESET,
+            "-threads",
+            FFMPEG_ENCODE_THREADS,
             "-pix_fmt",
             "yuv420p",
             "-movflags",
@@ -2128,16 +2114,11 @@ class UnifiedRenderService:
 
     @staticmethod
     def _clip_effective_duration(clip: ResolvedClip) -> float:
-        """计算 clip 的有效时长（原速 trim 后时长）。
+        """计算 clip 的有效时长（#1749：目标段长为准，素材不足走末帧冻结）。
 
-        如果 playback_speed < 1（为补偿素材不足而减速），返回配置的 duration，
-        而非 min(duration, actual_duration)。
-        实际实现移至 packages.domain.render_layer_utils.clip_effective_duration。
+        实际实现移至 packages.domain.render_layer_utils.clip_effective_duration
+        （duration>0 直接返回；慢放补偿已删除）。
         """
-        speed = getattr(clip, "playback_speed", 1.0) or 1.0
-        # 减速场景：duration 已通过降低 playback_speed 补偿，返回配置的 duration
-        if speed < 1.0 - 1e-6 and clip.duration > 0:
-            return clip.duration
         return _clip_effective_duration_pure(clip.duration, clip.actual_duration)
 
     # ── 画中画（PiP）相关方法 ──────────────────────────────────────────────────
@@ -2241,6 +2222,82 @@ class UnifiedRenderService:
         """
         return _clip_playback_speed_pure(getattr(clip, "playback_speed", 1.0))
 
+    def _get_visual_perturbation(self) -> dict:
+        # 读取当前 plan 的视觉扰动参数（plan.config.visual_perturbation）
+        perturbation = (self.plan.config or {}).get("visual_perturbation") or {}
+        if not perturbation:
+            return {}
+        result = {
+            "hflip": bool(perturbation.get("hflip", False)),
+            "zoom_ratio": max(1.0, min(1.2, float(perturbation.get("zoom_ratio", 1.0) or 1.0))),
+            "speed_factor": max(0.8, min(1.2, float(perturbation.get("speed_factor", 1.0) or 1.0))),
+            "brightness_shift": max(-30, min(30, int(perturbation.get("brightness_shift", 0) or 0))),
+        }
+        # #1765：同时读取像素级扰动滤镜
+        pixel_pert = (self.plan.config or {}).get("pixel_perturbation") or {}
+        if pixel_pert:
+            result["pixel_perturbation"] = pixel_pert
+        return result
+
+    def _apply_visual_perturbation_pre_scale(self, filters: list[str], perturbation: dict) -> None:
+        # scale+pad 之前的扰动（hflip），就地修改 filters
+        if perturbation.get("hflip"):
+            filters.append("hflip")
+
+    def _apply_visual_perturbation_post_scale(self, filters: list[str], perturbation: dict) -> None:
+        # scale+pad 之后的扰动（zoom/brightness），就地修改 filters
+        zoom = perturbation.get("zoom_ratio", 1.0)
+        if zoom > 1.0 + 1e-6:
+            zoomed_w = int(self.output_width * zoom)
+            zoomed_h = int(self.output_height * zoom)
+            filters.append(f"scale={zoomed_w}:{zoomed_h}")
+            filters.append(f"crop={self.output_width}:{self.output_height}")
+        brightness = perturbation.get("brightness_shift", 0)
+        if brightness != 0:
+            filters.append(f"eq=brightness={brightness / 100.0:.3f}")
+
+        # #1765：追加像素级扰动滤镜
+        pixel_pert = perturbation.get("pixel_perturbation") or {}
+        if pixel_pert:
+            self._apply_pixel_perturbation(filters, pixel_pert)
+
+    def _apply_pixel_perturbation(self, filters: list[str], pixel_pert: dict) -> None:
+        """应用像素级扰动滤镜（Issue #1765）。
+
+        滤镜参数幅度确保肉眼不可见（SSIM > 0.95），但能让同素材不同变体
+        在帧级产生 > 3% 的差异，降低平台查重风险。
+        """
+        filter_list = pixel_pert.get("filters") or []
+
+        for filt in filter_list:
+            if filt == "noise":
+                # 轻微噪声：noise=alls=0.015:allf=t+u
+                strength = pixel_pert.get("noise_strength", 0.015)
+                filters.append(f"noise=alls={strength}:allf=t+u")
+
+            elif filt == "unsharp":
+                # 锐化/柔化：unsharp=3:3:amount
+                # amount > 0 锐化，< 0 柔化
+                amount = pixel_pert.get("unsharp_amount", 0.0)
+                if abs(amount) > 0.01:
+                    filters.append(f"unsharp=3:3:{amount:.2f}")
+
+            elif filt == "curves":
+                # 对比度微调：curves 用 preset 或手动定义
+                # 简单方案：用 eq=contrast 代替（curves 语法复杂）
+                contrast = pixel_pert.get("curves_contrast", 1.0)
+                if abs(contrast - 1.0) > 0.01:
+                    filters.append(f"eq=contrast={contrast:.3f}")
+
+            elif filt == "color_balance":
+                # RGB 通道偏移：color_balance=rs=...:gs=...:bs=...
+                r = pixel_pert.get("color_r", 0)
+                g = pixel_pert.get("color_g", 0)
+                b = pixel_pert.get("color_b", 0)
+                if r != 0 or g != 0 or b != 0:
+                    # color_balance 参数范围 -1.0 ~ 1.0，这里用 /100 转换
+                    filters.append(f"color_balance=rs={r/100:.3f}:gs={g/100:.3f}:bs={b/100:.3f}")
+
     @staticmethod
     def _clip_volume(clip: ResolvedClip) -> float:
         """获取 clip 的音量（config.volume）。缺省 1.0 原声，0.0 静音。"""

apps/worker/worker_app/core/asset_usage.py

@@ -1,10 +1,20 @@
 from datetime import datetime, timezone
 
 
-def mark_asset_used_for_generation(asset) -> None:
+def mark_asset_used_for_generation(asset, times: int = 1) -> None:
+    """标记素材在成片中被使用，累加使用次数。
+
+    Args:
+        asset: Asset 实体（metadata 就地更新）
+        times: 本次成片实际使用次数（= 最终成片 plan 中引用该素材的片段数）。
+            按「成片实际渲染的片段」计数而非请求传入的 asset_ids 列表——
+            请求列表可能含未被 plan 选用的素材（不应计数），同一素材在多片段
+            复用时应按片段数累加（高频排除/未使用偏好才与真实渲染强度挂钩）。
+    """
+    times = max(1, int(times or 1))
     asset.metadata = {
         **asset.metadata,
-        "generation_use_count": int(asset.metadata.get("generation_use_count") or 0) + 1,
+        "generation_use_count": int(asset.metadata.get("generation_use_count") or 0) + times,
         "last_used_at": datetime.now(timezone.utc).isoformat(),
         "review_status": asset.metadata.get("review_status") or "pending_review",
     }

apps/worker/worker_app/tasks/generation.py

@@ -376,42 +376,137 @@ def _load_task_info(task_id: str) -> dict | None:
             "output_height": getattr(gen_task, "output_height", OUTPUT_HEIGHT) or OUTPUT_HEIGHT,
             "cover_url": getattr(gen_task, "cover_url", "") or "",
             "title_config": dict(getattr(gen_task, "title_config", {}) or {}),
-            "voice_ids": list(getattr(gen_task, "voice_ids", []) or []),
             "source_edit_plan_id": getattr(gen_task, "source_edit_plan_id", "") or "",
         }
     finally:
         session.close()
 
 
-def _upload_and_record(
+# ── #1743 批量变体重渲/封面判定（纯函数，便于单测） ──────────────────────
+BATCH_RENDER_SIMILARITY_LIMIT = 0.20
+"""批次内成片查重相似度阈值：超过则重选独立 plan 重渲一次（20%）。"""
+
+
+def should_rerender_for_batch_dedup(*, batch_id: str, render_attempt: int, batch_similarity) -> bool:
+    """批次内查重后判定是否需要重选 plan 重渲。
+
+    条件（全部满足才重渲）：批次任务、首版（attempt==0）、查重率已得出、相似度 > 20%。
+    非批次任务 / 已是重渲版 / 查重率缺失 / 相似度达标 → 不重渲。
+    """
+    if not batch_id:
+        return False
+    if render_attempt >= 1:
+        return False
+    if batch_similarity is None:
+        return False
+    return float(batch_similarity) > BATCH_RENDER_SIMILARITY_LIMIT
+
+
+def pick_batch_cover_index(task_id: str, candidate_count: int) -> int:
+    """批次变体封面帧选取：按 task_id md5 稳定哈希分散到候选帧。
+
+    同任务重试结果稳定；批次内不同 task_id 哈希后分散，避免 N 个变体都抽 frame_0
+    导致封面雷同。非批次调用方应直接取 0（主流程按 batch_id 区分）。
+    """
+    if candidate_count <= 1:
+        return 0
+    import hashlib
+
+    return int(hashlib.md5(task_id.encode()).hexdigest(), 16) % candidate_count
+
+
+def _count_plan_clip_asset_usage(session, plan_id: str) -> dict[str, int]:
+    """统计最终成片 plan 中每个素材被片段引用的次数。
+
+    计数口径（#1743）：以成片实际渲染的 edit_plan_clips 为准——
+    同一素材在多个片段复用按片段数累加；未被 plan 选用的素材（即使
+    出现在请求 asset_ids 中）不计数。
+    """
+    from packages.adapters.sqlalchemy_impl.models import EditPlanClipModel
+
+    rows = session.query(EditPlanClipModel.asset_id).filter(EditPlanClipModel.plan_id == plan_id).all()
+    counts: dict[str, int] = {}
+    for (asset_id,) in rows:
+        if asset_id:
+            counts[asset_id] = counts.get(asset_id, 0) + 1
+    return counts
+
+
+def _record_rendered_asset_usage(
+    session,
+    plan_id: str,
+    task_id: str,
+    fallback_asset_ids: list[str] | None = None,
+) -> int:
+    """按最终成片 plan 的实际片段统计素材使用次数并回写 metadata。
+
+    plan 无有效片段素材（异常数据）时退回 fallback_asset_ids 每个计 1 次，
+    保证使用统计不因数据异常完全丢失。单素材回写失败不影响其他素材。
+
+    Returns: 实际回写次数的素材数量。
+    """
+    from worker_app.core.asset_usage import mark_asset_used_for_generation
+
+    from packages.adapters.sqlalchemy_impl.asset_repository import (
+        SQLAlchemyAssetRepository,
+    )
+
+    used_counts = _count_plan_clip_asset_usage(session, plan_id)
+    if not used_counts and fallback_asset_ids:
+        used_counts = {aid: 1 for aid in fallback_asset_ids if aid}
+    if not used_counts:
+        logger.info("[task_id=%s] 素材使用计数: plan=%s 无有效片段素材，跳过", task_id, plan_id)
+        return 0
+
+    asset_repo = SQLAlchemyAssetRepository(session)
+    written = 0
+    for aid, times in used_counts.items():
+        try:
+            asset = asset_repo.get(aid)
+            if asset:
+                mark_asset_used_for_generation(asset, times=times)
+                asset_repo.update(asset)
+                written += 1
+        except Exception:
+            logger.warning(
+                "[task_id=%s] 更新素材使用次数失败: asset_id=%s times=%d",
+                task_id,
+                aid,
+                times,
+                exc_info=True,
+            )
+    logger.info(
+        "[task_id=%s] 素材使用计数回写完成(plan=%s): %d 个素材, 片段引用 %d 次",
+        task_id,
+        plan_id,
+        written,
+        sum(used_counts.values()),
+    )
+    return written
+
+
+def _upload_rendered_video(
     task_id: str,
     output_path: Path,
     project_id: str,
-    batch_id: str,
-    editing_mode,
-    user_id: str = "",
-    video_name: str = "",
-    thumbnail_url: str = "",
-) -> tuple[str, float, int, int]:
-    """上传 OSS、创建视频记录并查重。
+    *,
+    attempt: int = 0,
+) -> tuple[str, str]:
+    """上传成片到 OSS（不落库）。attempt>0 时文件名带轮次后缀，避免覆盖首版。
 
-    Returns:
-        (file_url, duration, file_size, video_count)
+    Returns: (file_url, storage_key)
     """
-    # project_id 可能为空（模板编辑器草稿不属于任何项目），过滤空段避免 OSS key 出现 //
-    path_parts = [p for p in ("generated", "projects", project_id, "tasks", task_id, output_path.name) if p]
+    suffix = f"_v{attempt}" if attempt > 0 else ""
+    stem = output_path.stem
+    name = f"{stem}{suffix}{output_path.suffix or '.mp4'}"
+    path_parts = [p for p in ("generated", "projects", project_id, "tasks", task_id, name) if p]
     storage_key = "/".join(path_parts)
-    file_size = output_path.stat().st_size
 
-    # 上传 OSS
-    logger.info("[task_id=%s] [OSS上传] 开始上传: size=%d", task_id, file_size)
-    upload_start = time.monotonic()
+    logger.info("[task_id=%s] [OSS上传] 开始上传(attempt=%d): size=%d", task_id, attempt, output_path.stat().st_size)
     file_url = upload_to_oss(output_path, storage_key)
-    upload_elapsed = time.monotonic() - upload_start
     if not file_url:
         raise RuntimeError(f"OSS 上传失败: task_id={task_id}, storage_key={storage_key}")
 
-    # 校验 URL 可达性（P0-2: 私有 bucket 用预签名 + object_exists 降级）
     verify_url = get_signed_download_url(file_url, expires_seconds=300) or file_url
     if not _verify_url_accessible(verify_url):
         from video_processing.oss_helpers import normalize_storage_key, oss_bucket
@@ -420,25 +515,64 @@ def _upload_and_record(
         key = normalize_storage_key(file_url)
         if not (bucket and bucket.object_exists(key)):
             raise RuntimeError(
-                f"OSS 上传后 URL 不可访问且 object_exists 失败: file_url={file_url}, " f"storage_key={storage_key}"
+                f"OSS 上传后 URL 不可访问且 object_exists 失败: file_url={file_url}, storage_key={storage_key}"
             )
-        logger.info(
-            "URL 校验失败但 object_exists 确认文件存在，视为上传成功: storage_key=%s",
-            key,
-        )
+        logger.info("URL 校验失败但 object_exists 确认文件存在，视为上传成功: storage_key=%s", key)
+    return file_url, storage_key
 
-    logger.info(
-        "[task_id=%s] [OSS上传] 成功: 耗时=%.1fs, file_url=%s",
-        task_id,
-        upload_elapsed,
-        file_url,
-    )
 
-    # 创建 GeneratedVideo 记录 + 查重
-    duration = probe_duration(output_path)
+def _reselect_plan_for_batch_retry(task_id: str, plan_id: str, task_info: dict) -> str | None:
+    """批次内查重超阈值后，为当前任务重新独立选片生成新 plan（#1743 自动重渲）。
+
+    复用 API 侧同一套 EditPlanService.reselect_plan_for_variant（packages 层
+    variant_plan_selector 纯核心），素材池来自任务 asset_ids + 源 plan 素材。
+    成功返回新 plan_id；失败返回 None（调用方放弃重渲，保留首版）。
+    """
+    try:
+        from app.services.edit_plan_service import EditPlanService
+
+        db = SessionLocal()
+        try:
+            svc = EditPlanService(db)
+            asset_pool = list(task_info.get("task_asset_ids") or [])
+            _voice_dur = 0.0
+            try:
+                _voice_dur = float(task_info.get("voice_duration", 0.0) or 0.0)
+            except (TypeError, ValueError):
+                _voice_dur = 0.0
+            new_plan = svc.reselect_plan_for_variant(
+                plan_id,
+                asset_pool,
+                created_by_user_id=task_info.get("user_id", ""),
+                name_suffix="重渲变体",
+                voice_duration=_voice_dur,
+            )
+            return new_plan.id
+        finally:
+            db.close()
+    except Exception:
+        logger.warning("[task_id=%s] 批次重渲前重选 plan 失败，放弃重渲", task_id, exc_info=True)
+        return None
+
+
+def _record_video_and_dedup(
+    *,
+    task_id: str,
+    project_id: str,
+    batch_id: str,
+    editing_mode,
+    user_id: str,
+    file_url: str,
+    file_size: int,
+    video_path: str,
+    video_name: str = "",
+    thumbnail_url: str = "",
+) -> dict:
+    """成片落库 + 指纹查重（含批次内）。返回查重信息 dict。"""
+    duration = probe_duration(Path(video_path))
     dedup_session = SessionLocal()
     try:
-        video_count = create_video_record_and_dedup(
+        result = create_video_record_and_dedup(
             generation_task_id=task_id,
             project_id=project_id,
             user_id=user_id,
@@ -446,7 +580,7 @@ def _upload_and_record(
             file_url=file_url,
             file_size=file_size,
             duration=duration,
-            video_path=str(output_path),
+            video_path=video_path,
             mode=editing_mode.value,
             session=dedup_session,
             name=video_name,
@@ -454,11 +588,12 @@ def _upload_and_record(
         )
     finally:
         dedup_session.close()
-
-    return file_url, duration, file_size, video_count or 1
+    result["duration"] = duration
+    return result
 
 
 # ── Celery Task ──────────────────────────────────────────────────────────────
+# ── Celery Task ──────────────────────────────────────────────────────────────
 
 
 def _sync_task_config_to_plan(source_edit_plan_id: str, task_info: dict, db) -> str | None:
@@ -518,8 +653,8 @@ def _sync_task_config_to_plan(source_edit_plan_id: str, task_info: dict, db) ->
     # 配音下载
     voiceover_path: str | None = None
     voice_library_id = task_info.get("voice_library_id", "")
-    voice_ids = task_info.get("voice_ids", []) or []
-    effective_voice_id = voice_library_id or (voice_ids[0] if voice_ids else "")
+    # #1749：voice_ids 冗余字段已移除；配音一律以 voice_library_id 为准（独立配音每变体各自绑定）
+    effective_voice_id = voice_library_id or ""
 
     if effective_voice_id:
         import tempfile
@@ -729,19 +864,29 @@ def generate_video(self, task_id: str) -> dict:
                     gen_task.append_log("渲染模式", "从草稿数据渲染（与预览一致）")
                     _flush_logs(task_id, gen_task)
 
-                output_path, render_duration, cover_candidates, voiceover_tmp_path, render_temp_dir, thumbnail_url = (
-                    _render_from_edit_plan(
+                # ── 渲染→上传→查重→（批次超阈值则重选 plan 重渲一次）循环（#1743）──
+                current_plan_id = source_edit_plan_id
+                file_url = ""
+                duration = 0.0
+                file_size = 0
+                video_count = 1
+                file_size_final = 0
+                for render_attempt in range(2):  # 首版 + 最多 1 次重渲
+                    (
+                        output_path,
+                        render_duration,
+                        cover_candidates,
+                        voiceover_tmp_path,
+                        render_temp_dir,
+                        thumbnail_url,
+                    ) = _render_from_edit_plan(
                         task_id=task_id,
-                        source_edit_plan_id=source_edit_plan_id,
+                        source_edit_plan_id=current_plan_id,
                         task_info=task_info,
                     )
-                )
-                # 从这里开始，render_temp_dir 已赋值，必须确保异常时也能清理
-                try:
                     if gen_task:
-                        gen_task.append_log("渲染", f"渲染完成, 时长={render_duration:.1f}s")
+                        gen_task.append_log("渲染", f"渲染完成(第{render_attempt + 1}版), 时长={render_duration:.1f}s")
                         _flush_logs(task_id, gen_task)
-
                     _update_task_progress(task_id, 80, "渲染完成")
 
                     # ── 3.5 随机边缘裁剪降重（#1664） ──────────────────────────
@@ -751,7 +896,7 @@ def generate_video(self, task_id: str) -> dict:
                         cropped_path = random_edge_crop(output_path)
                         if cropped_path != output_path:
                             output_path = cropped_path
-                        if gen_task:
+                        if gen_task and render_attempt == 0:
                             gen_task.append_log("边缘裁剪", "已应用随机 2-5% 边缘裁剪降重")
                             _flush_logs(task_id, gen_task)
                         logger.info("[task_id=%s] 随机边缘裁剪完成: %s", task_id, output_path)
@@ -762,45 +907,110 @@ def generate_video(self, task_id: str) -> dict:
                             crop_err,
                             exc_info=True,
                         )
-                        if gen_task:
-                            gen_task.append_log("边缘裁剪", f"裁剪失败，使用原始视频: {crop_err}")
-                            _flush_logs(task_id, gen_task)
 
-                    # ── 4. 上传 OSS + 查重记录 ───────────────────────────────
+                    # ── 4. 上传 OSS（不落库） ───────────────────────────────
                     _update_task_progress(task_id, 85, "开始上传")
-                    file_url, duration, file_size, video_count = _upload_and_record(
+                    file_url, _storage_key = _upload_rendered_video(
                         task_id=task_id,
                         output_path=output_path,
                         project_id=project_id,
+                        attempt=render_attempt,
+                    )
+                    file_size = output_path.stat().st_size
+
+                    # ── 4.5 落库 + 查重（批次任务检查批次内相似度） ───────────
+                    dedup_info = _record_video_and_dedup(
+                        task_id=task_id,
+                        project_id=project_id,
                         batch_id=batch_id,
                         editing_mode=editing_mode,
                         user_id=user_id,
+                        file_url=file_url,
+                        file_size=file_size,
+                        video_path=str(output_path),
                         video_name=task_info.get("video_title", ""),
                         thumbnail_url=thumbnail_url,
                     )
+                    duration = dedup_info.get("duration", render_duration)
+                    video_count = dedup_info.get("video_count", 1)
+                    batch_sim = dedup_info.get("batch_similarity")
 
                     if gen_task:
                         gen_task.append_log(
                             "OSS上传",
-                            f"上传成功, 大小={file_size}",
+                            f"第{render_attempt + 1}版上传成功, 大小={file_size}"
+                            + (f", 批次相似度={batch_sim:.0%}" if batch_sim is not None else ""),
                             file_size=file_size,
                             file_url=file_url,
                         )
                         _flush_logs(task_id, gen_task)
 
-                    _update_task_progress(task_id, 95, "上传完成")
-                finally:
-                    # 清理渲染临时目录（无论后续步骤成功与否都清理）
+                    # 非批次 / 相似度达标 / 已是最后一次 → 结束循环
+                    if not should_rerender_for_batch_dedup(
+                        batch_id=batch_id,
+                        render_attempt=render_attempt,
+                        batch_similarity=batch_sim,
+                    ):
+                        file_size_final = file_size
+                        break
+
+                    # 批次内相似度过高：重选独立 plan 后重渲一次
+                    logger.warning(
+                        "[task_id=%s] 批次内查重相似度 %.2f 超阈值 %.2f，重选 plan 重渲",
+                        task_id,
+                        batch_sim,
+                        BATCH_RENDER_SIMILARITY_LIMIT,
+                    )
+                    if gen_task:
+                        gen_task.append_log("批次查重", f"与批次内成片相似度过高({batch_sim:.0%})，重新选片渲染")
+                        _flush_logs(task_id, gen_task)
+                    new_plan_id = _reselect_plan_for_batch_retry(task_id, current_plan_id, task_info)
+                    if not new_plan_id:
+                        logger.warning("[task_id=%s] 重选 plan 失败，保留首版", task_id)
+                        file_size_final = file_size
+                        break
+                    # 回写任务关联的 plan（重渲版以新 plan 渲染）
+                    try:
+                        _ps = SessionLocal()
+                        try:
+                            from packages.adapters.sqlalchemy_impl.generation_task_repository import (
+                                SQLAlchemyGenerationTaskRepository,
+                            )
+
+                            _pr = SQLAlchemyGenerationTaskRepository(_ps)
+                            _gt = _pr.get(task_id)
+                            if _gt:
+                                _gt.source_edit_plan_id = new_plan_id
+                                _pr.update(_gt)
+                        finally:
+                            _ps.close()
+                    except Exception:
+                        logger.warning("[task_id=%s] 回写重渲 plan_id 失败", task_id, exc_info=True)
+                    current_plan_id = new_plan_id
+                    # 清理本轮临时目录，下一轮重新渲染
                     if render_temp_dir:
                         import shutil
 
                         shutil.rmtree(render_temp_dir, ignore_errors=True)
-                        logger.info("[task_id=%s] 渲染临时目录已清理: %s", task_id, render_temp_dir)
+                        render_temp_dir = None
+
+                file_size = file_size_final or file_size
+                _update_task_progress(task_id, 95, "上传完成")
+
+                # 渲染结束后清理临时目录（重渲循环内每轮已清理，此处兜底最后一轮）
+                if render_temp_dir:
+                    import shutil
+
+                    shutil.rmtree(render_temp_dir, ignore_errors=True)
+                    logger.info("[task_id=%s] 渲染临时目录已清理: %s", task_id, render_temp_dir)
 
                 # ── 4.5 封面帧持久化 ────────────────────────────────────────────
                 try:
                     if cover_candidates:
-                        first = cover_candidates[0]
+                        # #1743：批量变体封面差异化——候选帧按 task_id 稳定哈希分散选取
+                        # （同任务重试稳定，批次内不同任务落在不同帧位），非批次取首帧。
+                        _cover_idx = pick_batch_cover_index(task_id, len(cover_candidates)) if batch_id else 0
+                        first = cover_candidates[_cover_idx]
                         cover_frame_url = first.get("image_url") or first.get("url") or ""
                         if cover_frame_url:
                             _cover_session = SessionLocal()
@@ -859,35 +1069,22 @@ def generate_video(self, task_id: str) -> dict:
                     logger.warning("[task_id=%s] 更新标题使用次数异常", task_id, exc_info=True)
 
                 # 5.2 更新素材使用次数
+                # 按「最终成片 plan 实际渲染的片段」计数（#1743）：不用请求传入的
+                # task.asset_ids（可能含未被 plan 选用的素材），同一素材多片段复用
+                # 按片段数累加，使 unused_bonus / 高频排除与真实渲染强度挂钩。
+                # current_plan_id 是重渲循环结束后最终成片所用 plan（首版或重渲版）。
                 try:
-                    from worker_app.core.asset_usage import mark_asset_used_for_generation
-
                     _asset_session = SessionLocal()
                     try:
-                        from packages.adapters.sqlalchemy_impl.asset_repository import (
-                            SQLAlchemyAssetRepository,
-                        )
                         from packages.adapters.sqlalchemy_impl.generation_task_repository import (
                             SQLAlchemyGenerationTaskRepository,
                         )
 
-                        _task_repo = SQLAlchemyGenerationTaskRepository(_asset_session)
-                        _asset_repo = SQLAlchemyAssetRepository(_asset_session)
-                        _gen_task = _task_repo.get(task_id)
-                        if _gen_task and _gen_task.asset_ids:
-                            for _aid in _gen_task.asset_ids:
-                                try:
-                                    _asset = _asset_repo.get(_aid)
-                                    if _asset:
-                                        mark_asset_used_for_generation(_asset)
-                                        _asset_repo.update(_asset)
-                                except Exception:
-                                    logger.warning(
-                                        "[task_id=%s] 更新素材使用次数失败: asset_id=%s",
-                                        task_id,
-                                        _aid,
-                                        exc_info=True,
-                                    )
+                        _fallback_ids: list[str] = []
+                        _gt_for_assets = SQLAlchemyGenerationTaskRepository(_asset_session).get(task_id)
+                        if _gt_for_assets:
+                            _fallback_ids = list(_gt_for_assets.asset_ids or [])
+                        _record_rendered_asset_usage(_asset_session, current_plan_id, task_id, _fallback_ids)
                     finally:
                         _asset_session.close()
                 except Exception:

packages/application/auth/wechat_sync_use_case.py

@@ -34,7 +34,7 @@ class WechatSyncRequest:
     ):
         self.openid = openid.strip()
         self.unionid = unionid.strip() if unionid else ""
-        self.nickname = nickname or "微信用户"
+        self.nickname = nickname or "小虾同学"  # 微信新规拿不到真实昵称，新用户默认昵称
         self.avatar_url = avatar_url or ""
         self.source = source
 
@@ -227,7 +227,7 @@ class WechatSyncUseCase:
             id=user_id,
             email=email,
             username=username,
-            display_name=request.nickname or "微信用户",
+            display_name=request.nickname or "小虾同学",
             password_hash=password_hash,
             email_verified=True,  # 微信登录视为已验证
             wechat_openid=request.openid,

packages/application/generation_tasks.py

@@ -16,7 +16,6 @@ class CreateGenerationTaskCommand:
     template_id: str = ""
     asset_ids: list[str] = field(default_factory=list)
     title_ids: list[str] = field(default_factory=list)
-    voice_ids: list[str] = field(default_factory=list)
     created_by_user_id: str = ""
     source_edit_plan_id: str = ""
     asset_select_mode: str = ""
@@ -48,7 +47,7 @@ class CreateGenerationTaskUseCase:
             template_id=command.template_id,
             asset_ids=command.asset_ids,
             title_ids=command.title_ids,
-            voice_ids=command.voice_ids,
+            voice_ids=[],  # #1749：voice_ids 已废弃（冗余 voice_library_id），DB 列保留只读
             status="pending",  # type: ignore[arg-type]
             progress=0.0,
             result_count=0,

packages/domain/ass_subtitle_builder.py

@@ -20,8 +20,8 @@ logger = logging.getLogger(__name__)
 # ── 常量 ──────────────────────────────────────────────────────────────────────
 
 # Title/Subtitle 默认边距（像素）
-TITLE_MARGIN_TOP = 120
-TITLE_MARGIN_BOTTOM = 60
+TITLE_MARGIN_TOP = 180
+TITLE_MARGIN_BOTTOM = 100
 TITLE_MARGIN_SIDE = 40
 
 # 字体名称映射：前端中文字体名 → 服务器实际注册名（ffmpeg/ASS 通过注册名匹配字体）

packages/domain/render_layer_utils.py

@@ -94,22 +94,23 @@ def clip_effective_duration(
     duration: float,
     actual_duration: float = 0.0,
 ) -> float:
-    """计算 clip 的有效时长（原速 trim 后时长）。
+    """计算 clip 的有效时长（#1749：目标段长始终为准）。
 
     规则：
-    - duration > 0: min(duration, actual_duration)，actual=0 时用 duration
-    - duration <= 0: actual_duration，actual=0 时返回 0
+    - duration > 0: 直接返回 duration（配音分配的目标段长；素材短于段长的部分
+      由渲染侧末帧冻结 tpad / 音频 apad 铺满，不在此处钳制）；
+    - duration <= 0: actual_duration，actual=0 时返回 0。
 
     Args:
-        duration: 配置的时长（0 表示使用完整素材）
+        duration: 配置的目标时长（0 表示使用完整素材）
         actual_duration: 素材实际时长（probe 后的结果）
 
     Returns:
         有效时长（秒）
     """
     if duration > 0:
-        return min(duration, actual_duration) if actual_duration > 0 else duration
-    return actual_duration if actual_duration > 0 else 0.0
+        return float(duration)
+    return float(actual_duration) if actual_duration > 0 else 0.0
 
 
 def clip_playback_speed(playback_speed: Any) -> float:
@@ -182,7 +183,7 @@ def estimate_total_duration(
     if not main_layer or not getattr(main_layer, "clips", None):
         return 0.0
 
-    clips = getattr(main_layer, "clips", [])
+    clips = list(getattr(main_layer, "clips", []))
     total = sum(
         clip_adjusted_duration(
             duration=getattr(c, "duration", 0),
@@ -192,12 +193,19 @@ def estimate_total_duration(
         for c in clips
     )
 
-    # 减去转场重叠时间（粗略估算）
-    n_clips = len(clips)
-    if n_clips > 1 and transition_duration > 0:
-        total -= (n_clips - 1) * transition_duration
+    # #1749：逐处转场重叠扣减，与 voice_duration_planner 分配口径严格一致
+    # （cut 零重叠；非 cut 按该 clip 自身 transition_duration；转场挂在后段）。
+    for c in clips[1:]:
+        effect = (getattr(c, "transition_effect", "cut") or "cut").strip().lower()
+        if effect in ("cut", "", "none"):
+            continue
+        tdur = float(getattr(c, "transition_duration", 0.0) or 0.0)
+        if tdur > 0:
+            total -= tdur
+        elif transition_duration > 0:
+            total -= transition_duration
 
-    return max(0.1, total)
+    return max(0.1, round(total, 3))
 
 
 # ── 直通 / Stream Copy 判断辅助 ──────────────────────────────────────────────

packages/domain/smart_match.py

@@ -10,6 +10,7 @@
 from __future__ import annotations
 
 import math
+import random
 from dataclasses import dataclass, field
 from datetime import datetime, timezone
 from typing import Any
@@ -130,6 +131,7 @@ def smart_select_assets(
     limit: int | None = None,
     kind: str | None = None,
     now: datetime | None = None,
+    rng: random.Random | None = None,
 ) -> list[SmartMatchResult]:
     """从素材列表中智能选取素材。
 
@@ -138,9 +140,11 @@ def smart_select_assets(
         limit: 最大返回数量，None 表示不限制
         kind: 按文件类型过滤（video/image/audio），None 表示不过滤
         now: 当前时间（用于测试注入）
+        rng: 随机数生成器（用于测试注入，控制排序噪声可复现）
 
     Returns:
-        按得分降序排列的 SmartMatchResult 列表
+        按有效得分（综合得分 + 随机噪声）降序排列的 SmartMatchResult 列表。
+        r.score 始终为无噪声的原始综合得分；噪声仅用于排序/分桶顺序。
     """
     # Step 1: 过滤 ready 状态
     ready_assets = [a for a in assets if _get_enum_value(a, "status") == "ready"]
@@ -158,22 +162,39 @@ def smart_select_assets(
         total, breakdown = score_asset(a, now=now)
         scored.append(SmartMatchResult(asset=a, score=total, breakdown=breakdown))
 
-    # Step 4: 按得分降序排序
-    scored.sort(key=lambda r: r.score, reverse=True)
+    # Step 4: 按「得分 + 随机噪声」降序排序
+    # 同分/近分素材（分差 <= SCORE_RANDOM_NOISE_MAX）每次选出的顺序与组合不同，
+    # 从素材组合层面降低成片重复率；分差显著（>20）的高质量素材排名不受影响。
+    # 噪声以 asset.id 为 key 缓存，保证同一次调用内排序与分桶轮询顺序一致。
+    rng = rng or random.Random()
+    noise_by_asset: dict[str, float] = {
+        getattr(a, "id", ""): rng.uniform(0.0, SCORE_RANDOM_NOISE_MAX) for a in ready_assets
+    }
 
-    # Step 5: 多样性保障 — 时长分桶均衡选取
+    def _effective(r: SmartMatchResult) -> float:
+        return r.score + noise_by_asset.get(getattr(r.asset, "id", ""), 0.0)
+
+    scored.sort(key=_effective, reverse=True)
+
+    # Step 5: 多样性保障 — 时长分桶均衡选取（桶内同样按含噪声顺序）
     if limit and limit > 0 and len(scored) > limit:
-        scored = _diversity_select(scored, limit)
+        scored = _diversity_select(scored, limit, effective_key=_effective)
     elif limit and limit > 0:
         scored = scored[:limit]
 
     return scored
 
 
-def _diversity_select(scored: list[SmartMatchResult], limit: int) -> list[SmartMatchResult]:
+def _diversity_select(
+    scored: list[SmartMatchResult],
+    limit: int,
+    effective_key: Any | None = None,
+) -> list[SmartMatchResult]:
     """从已排序的候选中按分桶均衡选取，避免全选中同一时长档。
 
-    策略：轮流从 short/medium/long 桶中按得分顺序取，直到凑满 limit。
+    策略：轮流从 short/medium/long 桶中按顺序取，直到凑满 limit。
+    scored 已按含噪声的有效得分排序，桶内直接继承该顺序；
+    effective_key 给出时最终输出也按有效得分排序（同一次调用内噪声一致）。
     """
     buckets: dict[str, list[SmartMatchResult]] = {
         "short": [],
@@ -209,6 +230,6 @@ def _diversity_select(scored: list[SmartMatchResult], limit: int) -> list[SmartM
         if not added:
             break
 
-    # 按原始得分降序输出
-    selected.sort(key=lambda r: r.score, reverse=True)
+    # 按有效得分（含噪声）降序输出；未传 effective_key 时退回原始得分
+    selected.sort(key=effective_key or (lambda r: r.score), reverse=True)
     return selected

packages/domain/variant_plan_selector.py

@@ -0,0 +1,394 @@
+"""批量变体独立选片核心（#1743 起，#1749 强化素材级去重）。
+
+总原则：多视频 = 单视频逻辑 × N。批量正式生成/批量预览/variant-plans 时，
+每个变体**完整重跑单视频的选片流程**：
+
+1. 源 plan 片段骨架（clip_type/order/text/transition）保持不变；
+2. 素材池选片（#1749 定稿三轮策略）：
+   - **第一轮 fresh 素材优先**：本批次尚未被任何变体使用过的素材优先分配，
+     从根上避免跨视频素材重复；
+   - **第二轮受控复用**：fresh 素材不足时才允许复用已用素材，但必须通过
+     起点扫描（_best_start_for_asset，0.25s 窗口）使与批次内已有区间的
+     overlap ≤ 20%（BATCH_CLIP_OVERLAP_LIMIT），且不得完全重叠；
+   - **短素材数学上无法错开**（素材时长 < 段长 ×(1−0.20)，任何起点
+     重叠都 >20%）→ **禁止跨变体复用**，跳过该素材继续找；
+   - **第三轮兜底尽力而为**：池子耗尽时取最优（重叠最小）起点，不报错、
+     不打断生成（#1749 铁律：任何情况下不得因素材时长/数量报错打断）；
+3. main 片段之间洗牌顺序；起点走场景镜头洗牌 + 随机起点 + 历史已用区间
+   避让（pick_scene_aware_start / _resolve_start_time，与单视频同一入口）；
+4. target_durations：#1749 配音时长分配后每段目标段长（voice_duration_planner），
+   落库到片段 duration；素材短于段长由渲染侧末帧冻结（tpad/apad）铺满。
+
+本模块只产出 clips_data（dict 列表），不碰 DB 事务边界；素材时长/场景点/
+已用区间由调用方注入，便于单测。
+"""
+
+from __future__ import annotations
+
+import logging
+import random
+
+from packages.domain.plan_generator_utils import _resolve_start_time
+
+logger = logging.getLogger(__name__)
+
+# ── 阈值常量 ────────────────────────────────────────────────────────────────
+BATCH_CLIP_OVERLAP_LIMIT = 0.20
+"""批次内同一素材片段时间区间重叠占比上限（20%）。超过则重选起点/换素材。"""
+
+VARIANT_RESELECT_MAX_ATTEMPTS = 6
+"""单片段重叠避让/起点重选的最大尝试次数。"""
+
+START_SCAN_STEP = 0.25
+"""复用素材时起点扫描窗口步长（秒）。"""
+
+MAIN_CLIP_TYPES = {"main"}
+"""参与素材洗牌重选的片段类型（intro/outro/overlay 等固定角色片段保持源 plan）。"""
+
+
+def _clip_overlap_ratio(
+    asset_id: str,
+    start: float,
+    duration: float,
+    batch_segments: dict[str, list[tuple[float, float]]],
+) -> float:
+    """计算新区间 [start, start+duration) 与批次内同素材已选区间的重叠占比。
+
+    返回重叠总时长 / 片段时长。
+    """
+    if not asset_id or duration <= 0:
+        return 0.0
+    end = start + duration
+    overlap = 0.0
+    for seg_start, seg_end in batch_segments.get(asset_id, []):
+        ov = max(0.0, min(end, seg_end) - max(start, seg_start))
+        overlap += ov
+    return min(1.0, overlap / duration)
+
+
+def _best_start_for_asset(
+    asset_id: str,
+    clip_duration: float,
+    asset_durations: dict[str, float],
+    batch_segments: dict[str, list[tuple[float, float]]],
+) -> tuple[float, float] | None:
+    """在素材可用范围内扫描起点，找重叠最小的 (start, ratio)。
+
+    扫描步长 START_SCAN_STEP；返回 (best_start, best_ratio)。
+    短素材（max_start<=0）直接返回 (0.0, ratio)——由调用方判断 ratio 是否可接受。
+    """
+    total = asset_durations.get(asset_id, 0.0)
+    if total <= 0:
+        return None
+    max_start = max(0.0, total - clip_duration)
+    if max_start <= 0.0:
+        return 0.0, _clip_overlap_ratio(asset_id, 0.0, clip_duration, batch_segments)
+    best_start, best_ratio = 0.0, 1.0
+    steps = int(max_start / START_SCAN_STEP) + 1
+    for i in range(steps + 1):
+        s = min(max_start, i * START_SCAN_STEP)
+        r = _clip_overlap_ratio(asset_id, s, clip_duration, batch_segments)
+        if r < best_ratio:
+            best_start, best_ratio = s, r
+        if r <= BATCH_CLIP_OVERLAP_LIMIT:
+            return s, r
+    return best_start, best_ratio
+
+
+def reselect_clips_for_variant(
+    source_clips: list[dict],
+    candidate_asset_ids: list[str],
+    *,
+    asset_durations: dict[str, float],
+    asset_scene_points: dict[str, list[float]] | None = None,
+    historical_used_segments: dict[str, list[tuple[float, float]]] | None = None,
+    batch_segments: dict[str, list[tuple[float, float]]] | None = None,
+    target_durations: list[float] | dict[int, float] | None = None,
+    rng: random.Random | None = None,
+) -> list[dict]:
+    """为一个变体基于源片段骨架重新独立选片。
+
+    Args:
+        source_clips: 源 plan 片段（dict 列表，每项至少含
+            order/asset_id/start_time/duration/clip_type，可含
+            playback_speed/transition_effect/transition_duration/text_content）。
+        candidate_asset_ids: 素材池（源 plan 素材 ∪ 批次任务素材）。
+        asset_durations: {asset_id: 时长秒}，起点避让/区间计算必需。
+        asset_scene_points: {asset_id: 场景切换点}，有则走镜头洗牌选起点。
+        historical_used_segments: 素材 metadata 中持久化的历史已用区间
+            （跨任务/跨变体避让），函数内会就地追加本变体选中的区间。
+        batch_segments: 本批次已选片段区间（变体间素材级去重 + 20% 重叠检查），
+            函数内会就地追加本变体选中的区间。
+        target_durations: #1749 配音分配后的每段目标时长（按 order 对齐的 list，
+            或 {order: duration} dict）；落库到片段 duration，素材不足由渲染冻结铺满。
+        rng: 可选随机数生成器（测试可注入固定种子）。
+
+    Returns:
+        clips_data: 与源片段等长、order 对齐的新片段 dict 列表。
+
+    Raises:
+        ValueError: 源片段为空 / 素材池为空 / 素材时长全为 0（无法差异化选片）。
+    """
+    if rng is None:
+        rng = random.Random()
+    elif isinstance(rng, int):
+        rng = random.Random(rng)
+    if not source_clips:
+        raise ValueError("源 plan 无片段，无法为变体重新选片")
+    if not candidate_asset_ids:
+        raise ValueError("素材池为空，无法为变体独立选片（不允许退回同源成片）")
+
+    # 仅保留时长可知（>0）的素材；时长未知无法做区间避让/重叠计算
+    usable_assets = [a for a in dict.fromkeys(candidate_asset_ids) if asset_durations.get(a, 0.0) > 0]
+    if not usable_assets:
+        raise ValueError("素材池时长全部未知（0），无法为变体独立选片")
+
+    # 历史已用区间：复制一份，本变体选中的区间就地追加（随 clip record 持久化由调用方负责）
+    used_segments: dict[str, list[tuple[float, float]]] = (
+        {k: list(v) for k, v in (historical_used_segments or {}).items()} if historical_used_segments else {}
+    )
+    batch_segments = batch_segments if batch_segments is not None else {}
+
+    # 按 order 排序源片段，保持骨架顺序
+    ordered = sorted(source_clips, key=lambda c: c.get("order", 0))
+
+    def _target_dur(idx: int, src: dict) -> float:
+        """配音分配的目标段长（优先），否则用源片段段长。"""
+        if target_durations is not None:
+            if isinstance(target_durations, dict):
+                v = target_durations.get(idx, target_durations.get(src.get("order", 0)))
+            else:
+                v = target_durations[idx] if idx < len(target_durations) else None
+            if v is not None and float(v) > 0:
+                return float(v)
+        return float(src.get("duration", 0.0) or 0.0)
+
+    # ── 1. 素材池洗牌（组合随机），分 fresh / 已用两轮 ──────────────────────
+    shuffled_pool = list(usable_assets)
+    rng.shuffle(shuffled_pool)
+
+    # ── 2. main 片段之间洗牌顺序（顺序随机） ────────────────────────────────
+    main_indexes = [i for i, c in enumerate(ordered) if c.get("clip_type", "main") in MAIN_CLIP_TYPES]
+    rng.shuffle(main_indexes)
+
+    result: list[dict | None] = [None] * len(ordered)
+
+    for idx in main_indexes:
+        src = ordered[idx]
+        target_dur = _target_dur(idx, src)
+        if target_dur <= 0:
+            # 异常片段：原样保留
+            result[idx] = _base_clip_data(
+                src, asset_id=src.get("asset_id", ""), start=float(src.get("start_time", 0.0)), duration=target_dur
+            )
+            continue
+
+        asset_id, start, eff_dur = _pick_asset_and_start(
+            clip_duration=target_dur,
+            shuffled_pool=shuffled_pool,
+            asset_durations=asset_durations,
+            asset_scene_points=asset_scene_points,
+            used_segments=used_segments,
+            batch_segments=batch_segments,
+            rng=rng,
+        )
+
+        interval = (start, start + eff_dur)
+        used_segments.setdefault(asset_id, []).append(interval)
+        batch_segments.setdefault(asset_id, []).append(interval)
+
+        result[idx] = _base_clip_data(src, asset_id=asset_id, start=start, duration=target_dur)
+
+    # ── 3. 非 main 片段（intro/outro/overlay 等固定角色）：保留源素材，仅重算起点 ──
+    for idx, c in enumerate(ordered):
+        if result[idx] is not None:
+            continue
+        src = c
+        aid = src.get("asset_id", "")
+        target_dur = _target_dur(idx, src)
+        start = float(src.get("start_time", 0.0))
+        total = asset_durations.get(aid, 0.0)
+        if aid and target_dur > 0 and total > 0:
+            # 固定角色片段也走批次避让（但不换素材）
+            eff_dur = min(target_dur, total)
+            scan = _best_start_for_asset(aid, eff_dur, asset_durations, batch_segments)
+            if scan is not None and scan[1] <= BATCH_CLIP_OVERLAP_LIMIT:
+                start = scan[0]
+            else:
+                cand = _resolve_start_time(aid, eff_dur, asset_durations, used_segments, asset_scene_points)
+                if cand is not None:
+                    start = cand
+                elif scan is not None:
+                    start = scan[0]
+            interval = (start, start + eff_dur)
+            used_segments.setdefault(aid, []).append(interval)
+            batch_segments.setdefault(aid, []).append(interval)
+        result[idx] = _base_clip_data(src, asset_id=aid, start=start, duration=target_dur)
+
+    return [c for c in result if c is not None]
+
+
+def _pick_asset_and_start(
+    *,
+    clip_duration: float,
+    shuffled_pool: list[str],
+    asset_durations: dict[str, float],
+    asset_scene_points: dict[str, list[float]] | None,
+    used_segments: dict[str, list[tuple[float, float]]],
+    batch_segments: dict[str, list[tuple[float, float]]],
+    rng: random.Random,
+) -> tuple[str, float, float]:
+    """三轮选片：fresh 优先 → 受控复用（重叠≤20%，短素材禁复用）→ 兜底尽力而为。
+
+    Returns:
+        (asset_id, start, eff_dur)：eff_dur = min(段长, 素材时长)，
+        段长超出素材时长的部分由渲染侧末帧冻结铺满。
+    """
+    # ── 第一轮：fresh 素材（本批次未用过）──────────────────────────────────
+    fresh = [a for a in shuffled_pool if a not in batch_segments]
+    rng.shuffle(fresh)
+    for asset_id in fresh:
+        total = asset_durations.get(asset_id, 0.0)
+        if total <= 0:
+            continue
+        eff_dur = min(clip_duration, total)
+        cand = _resolve_start_time(asset_id, eff_dur, asset_durations, used_segments, asset_scene_points)
+        if cand is None:
+            max_start = max(0.0, total - eff_dur)
+            cand = rng.uniform(0.0, max_start) if max_start > 0 else 0.0
+        # fresh 素材批次内无区间，重叠必然为 0，直接采用
+        return asset_id, cand, eff_dur
+
+    # ── 第二轮：受控复用 —— 扫描起点使重叠 ≤20%；短素材数学无法错开则跳过 ──
+    reused = [a for a in shuffled_pool if a in batch_segments]
+    rng.shuffle(reused)
+    fallback: tuple[str, float, float, float] | None = None  # (asset, start, eff, ratio)
+    for asset_id in reused:
+        total = asset_durations.get(asset_id, 0.0)
+        if total <= 0:
+            continue
+        eff_dur = min(clip_duration, total)
+        # 短素材判定：素材时长 < 段长 ×(1−0.20) → 任何起点重叠都 >20%，禁跨变体复用
+        if total < clip_duration * (1.0 - BATCH_CLIP_OVERLAP_LIMIT) - 1e-6:
+            logger.info(
+                "素材 %s 时长 %.2fs 短于段长 %.2fs 的 80%，数学上无法错开，禁止跨变体复用",
+                asset_id,
+                total,
+                clip_duration,
+            )
+            continue
+        scan = _best_start_for_asset(asset_id, eff_dur, asset_durations, batch_segments)
+        if scan is None:
+            continue
+        start, ratio = scan
+        if ratio <= BATCH_CLIP_OVERLAP_LIMIT:
+            return asset_id, start, eff_dur
+        if fallback is None or ratio < fallback[3]:
+            fallback = (asset_id, start, eff_dur, ratio)
+
+    # ── 第三轮：兜底尽力而为（池耗尽/全部超阈值）——不报错，取最优 ──────────
+    if fallback is not None:
+        asset_id, start, eff_dur, ratio = fallback
+        logger.info(
+            "变体选片素材池不足，受控复用重叠 %.0f%%（>20%% 阈值，尽力而为不打断）: asset=%s",
+            ratio * 100,
+            asset_id,
+        )
+        return asset_id, start, eff_dur
+
+    # 理论不可达（usable_assets 非空）；保底取池首
+    asset_id = shuffled_pool[0]
+    total = asset_durations.get(asset_id, 0.0)
+    eff_dur = min(clip_duration, total) if total > 0 else clip_duration
+    return asset_id, 0.0, eff_dur
+
+
+def generate_visual_perturbation(rng: random.Random | None = None) -> dict:
+    """为一个变体生成随机视觉扰动参数（让批量视频画面本身更不同）。
+
+    返回 dict，可直接存入 plan.config["visual_perturbation"]。
+    渲染侧读取后应用到 ffmpeg filter chain。
+
+    参数范围经过校准：
+    - hflip: 30% 概率水平翻转（画面左右镜像，肉眼立即可见）
+    - zoom_ratio: 1.0~1.08 随机缩放（最多放大 8%，裁剪后画面略有差异）
+    - speed_factor: 0.95~1.05 速度微调（±5%，肉眼不太敏感但时间轴不同）
+    - brightness_shift: -10~+10 亮度偏移（eq=brightness，画面明暗差异）
+    """
+    if rng is None:
+        rng = random.Random()
+    elif isinstance(rng, int):
+        rng = random.Random(rng)
+    return {
+        "hflip": rng.random() < 0.3,
+        "zoom_ratio": round(1.0 + rng.uniform(0, 0.08), 4),
+        "speed_factor": round(1.0 + rng.uniform(-0.05, 0.05), 4),
+        "brightness_shift": rng.choice([-10, -5, 0, 0, 0, 5, 10]),
+    }
+
+
+def generate_pixel_perturbation(rng: random.Random | int | None = None) -> dict:
+    """为一个变体生成像素级扰动滤镜参数（Issue #1765）。
+
+    在现有视觉扰动（hflip/zoom/brightness）基础上，额外叠加 2-3 种
+    像素级滤镜，让同素材不同变体在帧级 SSIM 差异 > 3%，肉眼看不出差异。
+
+    滤镜选项（随机选 2-3 种叠加）：
+    - noise: 轻微噪声 (noise=alls=0.015:allf=t+u)
+    - unsharp: 锐化或柔化 (unsharp=3:3:-0.5 ~ 3:3:0.5)
+    - curves: 对比度微调 (curves 轻微调整)
+    - color_balance: RGB 通道偏移 (color_balance 微调)
+
+    返回 dict，可直接存入 plan.config["pixel_perturbation"]。
+    渲染侧读取后追加到 ffmpeg filter chain。
+    """
+    if rng is None:
+        rng = random.Random()
+    elif isinstance(rng, int):
+        rng = random.Random(rng)
+
+    # 可用滤镜池
+    filter_options = ["noise", "unsharp", "curves", "color_balance"]
+
+    # 随机选 2-3 种
+    num_filters = rng.choice([2, 2, 3])
+    selected = rng.sample(filter_options, num_filters)
+
+    result: dict = {"filters": selected}
+
+    # 为每种滤镜生成具体参数
+    if "noise" in selected:
+        # 噪声强度 0.01~0.02（肉眼不可见）
+        result["noise_strength"] = round(rng.uniform(0.01, 0.02), 4)
+
+    if "unsharp" in selected:
+        # 锐化/柔化：-0.5 ~ +0.5（正值锐化，负值柔化）
+        result["unsharp_amount"] = round(rng.uniform(-0.5, 0.5), 2)
+
+    if "curves" in selected:
+        # 对比度微调：0.95 ~ 1.05
+        result["curves_contrast"] = round(rng.uniform(0.95, 1.05), 3)
+
+    if "color_balance" in selected:
+        # RGB 通道偏移：-5 ~ +5（极轻微色偏）
+        result["color_r"] = rng.choice([-5, -3, 0, 0, 3, 5])
+        result["color_g"] = rng.choice([-5, -3, 0, 0, 3, 5])
+        result["color_b"] = rng.choice([-5, -3, 0, 0, 3, 5])
+
+    return result
+
+
+def _base_clip_data(src: dict, *, asset_id: str, start: float, duration: float | None = None) -> dict:
+    """从源片段构造落库 dict（保留骨架/转场/文案/速度，替换素材与起点）。"""
+    return {
+        "order": src.get("order", 0),
+        "asset_id": asset_id,
+        "start_time": round(float(start), 3),
+        "duration": float(duration if duration is not None else src.get("duration", 0.0) or 0.0),
+        "clip_type": src.get("clip_type", "main"),
+        "playback_speed": float(src.get("playback_speed", 1.0) or 1.0),
+        "transition_effect": src.get("transition_effect", "cut"),
+        "transition_duration": float(src.get("transition_duration", 0.0) or 0.0),
+        "text_content": src.get("text_content", ""),
+        "config": src.get("config") or {},
+    }

packages/domain/variant_voice_resolver.py

@@ -0,0 +1,76 @@
+"""批量变体配音严格守卫与解析（#1749 问题 A）。
+
+事故：批量独立配音视频3 错绑视频1 配音——根因是 voice_library_ids
+缺值/长度不符时静默 fallback 到 voice_library_id（单值），导致多个变体
+共用同一条配音。
+
+定稿规则：
+- 独立配音（voice_library_ids 非空）：长度必须 == count，逐项非空，
+  否则 400；**禁止静默 fallback** 到单值 voice_library_id；
+- 统一配音（voice_library_id 非空、voice_library_ids 空）：所有变体共用；
+- 两者都空：返回 [""] * count（无配音，渲染走原 BGM/原声路径）。
+
+纯函数，不碰 DB；调用方（路由）负责把 VariantVoiceError 转 400。
+"""
+
+from __future__ import annotations
+
+from typing import List, Optional
+
+
+class VariantVoiceError(ValueError):
+    """配音参数错误（路由层捕获后返回 400）。"""
+
+
+def resolve_variant_voice_ids(
+    *,
+    count: int,
+    voice_library_id: Optional[str] = None,
+    voice_library_ids: Optional[List[str]] = None,
+) -> List[str]:
+    """解析每个变体使用的配音 voice_library_id。
+
+    Args:
+        count: 变体数量（必须 >= 1）。
+        voice_library_id: 统一配音 ID（所有变体共用）。
+        voice_library_ids: 独立配音 ID 列表，长度必须 == count。
+
+    Returns:
+        长度 == count 的列表；元素为 "" 表示该变体无配音。
+
+    Raises:
+        VariantVoiceError: count 非法 / 独立配音长度不符 / 存在缺值。
+    """
+    if not count or count < 1:
+        raise VariantVoiceError("变体数量 count 必须 >= 1")
+
+    single = (voice_library_id or "").strip()
+    # 归一化：None / 空列表 / 全空白 → 未提供独立配音（走统一配音或无配音）
+    raw_multi = [str(v or "").strip() for v in (voice_library_ids or [])]
+    multi = [v for v in raw_multi if v]
+
+    if multi:
+        # 显式传了独立配音列表：
+        # - 恰好 1 个非空且 count > 1：视为统一配音（与 cover_urls/titles 长度1=共用一致）；
+        # - 否则按独立配音严格校验：原始长度必须 == count 且逐项非空，禁止静默 fallback；
+        # - 其余长度/缺值 → 400。
+        if len(raw_multi) == 1 and count > 1:
+            return [multi[0]] * count
+        if len(raw_multi) != count:
+            raise VariantVoiceError(
+                f"独立配音数量({len(raw_multi)})与视频数量({count})不一致；"
+                f"批量独立配音必须为每个视频分别指定配音，或改用统一配音 voice_library_id"
+            )
+        missing = [i for i, v in enumerate(raw_multi) if not v]
+        if missing:
+            raise VariantVoiceError(
+                f"第 {[i + 1 for i in missing]} 个视频缺少独立配音 voice_library_id；"
+                f"独立配音不允许缺值，也不会回退为统一配音"
+            )
+        return list(raw_multi)
+
+    if single:
+        return [single] * count
+
+    # 无配音
+    return [""] * count

packages/domain/voice_duration_planner.py

@@ -0,0 +1,214 @@
+"""配音时长 → 片段时长分配纯函数（#1749 + #1764 节奏模板）。
+
+定稿规则（工单 #1749）：
+1. 片段数 = 模板片段数，定死，不因素材增减；
+2. 成片总时长 = 配音时长：逐段分配段长，含转场重叠扣减
+   （cut 零重叠；xfade 等转场按转场时长重叠），误差 < 0.5s；
+3. 素材短于段长 → 末帧冻结（tpad）/ 音频补静音（apad）铺满，
+   禁止慢放、禁止截断配音；
+4. 任何情况下不得因素材时长/数量报错打断用户。
+
+#1764 节奏模板：
+- 预设 6 种权重序列，不同变体用不同节奏模板
+- 片段时长 = 配音总时长 × 该片段权重 / 权重总和
+- 平均分配作为权重全 1 的特例保留
+- 每个片段 >= MIN_CLIP_DURATION（2秒）
+
+本模块为纯函数：输入片段骨架（每段转场效果/时长）与配音总时长，
+输出每段目标时长（target duration）与成片总时长。不碰 DB、不碰素材。
+"""
+
+from __future__ import annotations
+
+import logging
+import random
+from typing import Optional
+
+logger = logging.getLogger(__name__)
+
+#: 单段最小时长（秒）：低于此值播放器/渲染链路易出问题
+MIN_CLIP_DURATION = 2.0
+
+#: 成片总时长与配音时长的可接受误差（秒）
+TOTAL_DURATION_TOLERANCE = 0.5
+
+# ── #1764 节奏模板池 ──────────────────────────────────────────────────────
+# 每种模板是权重序列，权重值代表相对时长比例
+# 变体基于 variant_seed 随机选一个模板，实现不同变体时长结构不同
+RHYTHM_TEMPLATES: list[list[int]] = [
+    [1, 1, 1, 1, 1],  # 平均（基准）
+    [2, 1, 3, 1, 2],  # 中间长，两端短
+    [1, 2, 1, 2, 1],  # 偶数段长
+    [3, 1, 1, 1, 3],  # 两端长，中间短
+    [1, 1, 3, 2, 1],  # 后段渐长
+    [2, 1, 1, 3, 1],  # 前段较长 + 第4段最长
+]
+
+
+def get_rhythm_template(variant_seed: int | None = None) -> list[int]:
+    """根据 variant_seed 选择一个节奏模板。
+
+    Args:
+        variant_seed: 变体随机种子；None 时返回平均模板
+
+    Returns:
+        权重序列（list[int]）
+    """
+    if variant_seed is None:
+        return RHYTHM_TEMPLATES[0]  # 默认平均
+    rng = random.Random(variant_seed)
+    return rng.choice(RHYTHM_TEMPLATES)
+
+
+def adapt_template_length(template: list[int], clip_count: int) -> list[int]:
+    """将节奏模板适配到实际片段数。
+
+    片段数 != 模板长度时：
+    - clip_count < len(template): 截断
+    - clip_count > len(template): 循环填充
+
+    Args:
+        template: 原始权重序列
+        clip_count: 实际片段数
+
+    Returns:
+        适配后的权重序列（长度 == clip_count）
+    """
+    if clip_count <= 0:
+        return []
+    if clip_count == len(template):
+        return template[:]
+    if clip_count < len(template):
+        return template[:clip_count]
+    # clip_count > len(template): 循环填充
+    result = []
+    for i in range(clip_count):
+        result.append(template[i % len(template)])
+    return result
+
+
+#: 单段最小时长（秒）：低于此值播放器/渲染链路易出问题
+MIN_CLIP_DURATION = 1.0
+
+#: 成片总时长与配音时长的可接受误差（秒）
+TOTAL_DURATION_TOLERANCE = 0.5
+
+
+def transition_overlap_seconds(transition_effect: Optional[str], transition_duration: float) -> float:
+    """转场导致的相邻片段重叠时长。
+
+    cut（或空/None）无重叠；其余转场（xfade/fade/slide 等）按转场时长重叠。
+    """
+    effect = (transition_effect or "cut").strip().lower()
+    if effect in ("cut", "", "none"):
+        return 0.0
+    dur = float(transition_duration or 0.0)
+    return max(0.0, dur)
+
+
+def plan_clip_durations(
+    clip_count: int,
+    voice_duration: float,
+    transition_effects: Optional[list[Optional[str]]] = None,
+    transition_durations: Optional[list[float]] = None,
+    rhythm_template: Optional[list[int]] = None,
+) -> list[float]:
+    """把配音总时长分配到 clip_count 段，返回每段目标时长（秒）。
+
+    #1764：支持节奏模板，按权重比例分配时长；无模板时平均分配（向后兼容）。
+
+    分配口径：Σ段长 − Σ转场重叠 = 配音时长（成片净时长 = 配音）。
+    转场重叠发生在相邻片段之间，共 clip_count-1 处；第 i 处重叠取
+    **后一段（i+1）** 的转场设置（与 xfade 构建口径一致：转场挂在后段）。
+
+    舍入误差全部由最后一段吸收，保证 total_output_duration(结果) ≈ 配音。
+
+    Args:
+        clip_count: 片段数（模板定死，必须 > 0）。
+        voice_duration: 配音总时长（秒）；<=0 返回空列表表示"无配音"。
+        transition_effects: 每段转场效果（长度 clip_count，index 0 的转场无效）。
+        transition_durations: 每段转场时长（长度 clip_count）。
+
+    Returns:
+        每段目标时长列表（长度 clip_count）；无配音/非法输入返回 []。
+    """
+    if not clip_count or clip_count <= 0:
+        return []
+    try:
+        voice = float(voice_duration)
+    except (TypeError, ValueError):
+        return []
+    if voice <= 0:
+        return []
+
+    effects = transition_effects or [None] * clip_count
+    durations = transition_durations or [0.0] * clip_count
+
+    # 相邻片段间的转场重叠总和（转场挂在后段，取 i=1..clip_count-1）
+    total_overlap = 0.0
+    for i in range(1, clip_count):
+        effect = effects[i] if i < len(effects) else None
+        tdur = durations[i] if i < len(durations) else 0.0
+        total_overlap += transition_overlap_seconds(effect, tdur)
+
+    # 需要的段长总和 = 配音 + 重叠（重叠部分被算了两次，扣回一次）
+    gross = voice + total_overlap
+    if gross < clip_count * MIN_CLIP_DURATION:
+        # 配音极短：保底每段 MIN_CLIP_DURATION（成片略长于配音，末段可冻结）
+        gross = clip_count * MIN_CLIP_DURATION
+        logger.info(
+            "配音时长 %.2fs 过短，%d 段按最小段长 %.1fs 保底（成片将略长于配音）",
+            voice,
+            clip_count,
+            MIN_CLIP_DURATION,
+        )
+
+    # #1764：按节奏模板权重分配（无模板时全 1 = 平均分配）
+    weights = rhythm_template if rhythm_template and len(rhythm_template) == clip_count else [1] * clip_count
+
+    # 确保每个片段 >= MIN_CLIP_DURATION
+    # 先按权重分配，再检查最小值
+    total_weight = sum(weights)
+    raw_durations = [(w / total_weight) * gross for w in weights]
+
+    # 保底检查：如果有片段 < MIN_CLIP_DURATION，提升它并从最长片段扣
+    result = [round(d, 3) for d in raw_durations]
+    for _ in range(3):  # 最多迭代 3 次
+        min_idx = min(range(len(result)), key=lambda i: result[i])
+        if result[min_idx] >= MIN_CLIP_DURATION:
+            break
+        # 从最长片段借时长
+        max_idx = max(range(len(result)), key=lambda i: result[i])
+        if max_idx == min_idx or result[max_idx] <= MIN_CLIP_DURATION:
+            # 无法再调整，强制保底
+            result[min_idx] = MIN_CLIP_DURATION
+            break
+        deficit = MIN_CLIP_DURATION - result[min_idx]
+        result[min_idx] = MIN_CLIP_DURATION
+        result[max_idx] = round(result[max_idx] - deficit, 3)
+
+    # 末段吸收舍入误差
+    total_assigned = sum(result[:-1])
+    result[-1] = round(gross - total_assigned, 3)
+    if result[-1] < MIN_CLIP_DURATION:
+        result[-1] = MIN_CLIP_DURATION
+
+    return result
+
+
+def total_output_duration(
+    clip_durations: list[float],
+    transition_effects: Optional[list[Optional[str]]] = None,
+    transition_durations: Optional[list[float]] = None,
+) -> float:
+    """按分配后的段长与转场计算成片净时长 = Σ段长 − Σ转场重叠。"""
+    if not clip_durations:
+        return 0.0
+    effects = transition_effects or [None] * len(clip_durations)
+    durations = transition_durations or [0.0] * len(clip_durations)
+    total = sum(float(d) for d in clip_durations)
+    for i in range(1, len(clip_durations)):
+        effect = effects[i] if i < len(effects) else None
+        tdur = durations[i] if i < len(durations) else 0.0
+        total -= transition_overlap_seconds(effect, tdur)
+    return round(max(0.0, total), 3)

packages/shared/cover_frame_scorer.py

@@ -0,0 +1,141 @@
+"""封面帧质量评分器 — 评估视频帧的视觉质量，用于智能选帧。
+
+评分维度（总分 0~100）：
+1. 清晰度（0~40）：拉普拉斯方差，越高越清晰
+2. 亮度（0~30）：均值亮度，80~180 区间满分
+3. 色彩丰富度（0~30）：RGB 三维直方图非零 bin 数
+
+设计原则：
+- 纯函数，输入 numpy array，输出 float
+- 无副作用、无 IO、无网络
+- 不依赖 OpenCV 的 GUI 模块，仅用 cv2/numpy 的计算函数
+- 降级策略：cv2 不可用时返回 50.0（中间值）
+"""
+
+from __future__ import annotations
+
+import inspect
+import logging
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    import numpy as np
+
+logger = logging.getLogger(__name__)
+
+
+def score_frame(frame: "np.ndarray") -> float:
+    """评估单帧图像质量，返回 0~100 分（越高越好）。
+
+    Args:
+        frame: BGR 格式的 numpy array（OpenCV  imread 或 video capture 读取）
+
+    Returns:
+        float: 质量评分 0~100
+
+    评分维度：
+        - 清晰度 (0~40): 拉普拉斯方差，越高越清晰
+        - 亮度 (0~30): 均值亮度，80~180 区间满分
+        - 色彩丰富度 (0~30): RGB 三维直方图非零 bin 数
+    """
+    try:
+        import cv2
+        import numpy as np
+
+        # 确保 cv2 和 numpy 是真实的模块，不是 mock 对象
+        # MagicMock 会有所有属性，但调用结果不是真实数值类型
+        if not hasattr(cv2, "Laplacian") or not hasattr(np, "ndarray"):
+            raise ImportError("cv2/numpy 缺少核心方法")
+        # 验证 cv2 的核心函数是真实的 C/Python 函数，不是 MagicMock
+        if not inspect.isroutine(cv2.Laplacian) or "mock" in str(type(cv2.Laplacian)).lower():
+            raise ImportError("cv2 是 mock 对象")
+    except (ImportError, TypeError, AttributeError):
+        logger.warning("[cover_scorer] cv2/numpy 不可用或是 mock，返回默认分 50.0")
+        return 50.0
+
+    if frame is None or frame.size == 0:
+        return 0.0
+
+    # ── 1. 清晰度（拉普拉斯方差）────────────────────────────────────
+    # 拉普拉斯算子检测边缘，方差越大说明高频细节越多，图像越清晰
+    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
+    laplacian_var = cv2.Laplacian(gray, cv2.CV_64F).var()
+    # 归一化：一般视频拉普拉斯方差在 0~500 之间，映射到 0~40 分
+    clarity = min(laplacian_var / 500.0 * 40.0, 40.0)
+
+    # ── 2. 亮度（适中最好）──────────────────────────────────────────
+    # 均值亮度在 80~180 区间视觉舒适；过暗（<80）或过亮（>180）扣分
+    mean_brightness = float(np.mean(gray))
+    if 80.0 <= mean_brightness <= 180.0:
+        brightness_score = 30.0
+    else:
+        # 偏离舒适区间越远扣分越多，最多扣 30 分
+        deviation = abs(mean_brightness - 130.0) - 50.0  # 130 是舒适区中心
+        brightness_score = max(0.0, 30.0 - deviation * 0.3)
+
+    # ── 3. 色彩丰富度（RGB 三维直方图）──────────────────────────────
+    # 将 RGB 各通道量化为 8 个 bin，共 8x8x8=512 个 bin
+    # 非零 bin 越多说明色彩越丰富
+    hist = cv2.calcHist([frame], [0, 1, 2], None, [8, 8, 8], [0, 256] * 3)
+    nonzero_bins = float(np.count_nonzero(hist))
+    # 归一化：一般帧非零 bin 在 0~200 之间，映射到 0~30 分
+    color_richness = min(nonzero_bins / 200.0 * 30.0, 30.0)
+
+    total = clarity + brightness_score + color_richness
+    return round(total, 2)
+
+
+def score_frames(frames: list[dict]) -> list[dict]:
+    """批量评估帧质量，在每帧 dict 中增加 score 字段并排序。
+
+    Args:
+        frames: 帧列表，每项需包含 image_path 或 image_array。
+            支持格式：
+            - {"image_path": "/path/to/frame.jpg", ...}
+            - {"image_array": np.ndarray, ...}
+
+    Returns:
+        排序后的帧列表（分数从高到低），每项增加 "score" 字段
+    """
+    try:
+        import cv2
+    except ImportError:
+        logger.warning("[cover_scorer] cv2 不可用，跳过评分")
+        for f in frames:
+            f["score"] = 50.0
+        return frames
+
+    scored: list[dict] = []
+    for f in frames:
+        arr = f.get("image_array")
+        if arr is None:
+            path = f.get("image_path", "")
+            if path:
+                try:
+                    arr = cv2.imread(path)
+                except Exception:
+                    logger.warning("[cover_scorer] 读取帧图片失败: %s", path)
+        if arr is not None and arr.size > 0:
+            f["score"] = score_frame(arr)
+        else:
+            f["score"] = 0.0
+        scored.append(f)
+
+    # 按分数从高到低排序
+    scored.sort(key=lambda x: x.get("score", 0.0), reverse=True)
+    return scored
+
+
+def select_best_frame(frames: list[dict]) -> dict | None:
+    """从候选帧中选择质量最高的一帧。
+
+    Args:
+        frames: 帧列表，每项需包含 image_path 或 image_array
+
+    Returns:
+        评分最高的帧 dict（包含 score 字段），空列表返回 None
+    """
+    if not frames:
+        return None
+    scored = score_frames(frames)
+    return scored[0] if scored else None

packages/shared/ffmpeg_utils.py

@@ -9,6 +9,7 @@ application 层和 worker 层都可以引用本模块，避免跨层依赖。
 from __future__ import annotations
 
 import logging
+import os
 import shutil
 import subprocess  # nosec B404
 
@@ -23,6 +24,15 @@ FFPROBE_BIN: str = shutil.which("ffprobe") or "ffprobe"
 # 默认 30 分钟，足够处理大部分短视频渲染；超长视频可单独传参覆盖
 DEFAULT_FFMPEG_TIMEOUT = 1800
 
+# ── 编码参数（集中配置，支持环境变量覆盖）────────────────────────────────────
+# preset 从 medium → fast，渲染速度提升 30%+，画质几乎无损（CRF 相同时 PSNR 差异 <0.1dB）
+# 可通过环境变量 FFMPEG_ENCODE_PRESET 覆盖（如 ultrafast 追求极致速度，veryslow 追求极致压缩）
+FFMPEG_ENCODE_PRESET: str = os.environ.get("FFMPEG_ENCODE_PRESET", "fast")
+# CRF 保持 23（libx264 默认质量），可通过 FFMPEG_ENCODE_CRF 覆盖
+FFMPEG_ENCODE_CRF: str = os.environ.get("FFMPEG_ENCODE_CRF", "23")
+# 编码线程数：0 = 自动检测 CPU 核心数，充分利用多核
+FFMPEG_ENCODE_THREADS: str = os.environ.get("FFMPEG_ENCODE_THREADS", "0")
+
 
 # ── FFmpeg 执行 ───────────────────────────────────────────────────────────────
 

tests/integration/test_generation_api.py

@@ -347,8 +347,9 @@ class TestCreateGenerationTask:
         assert mock_celery.send_task.call_args[0][0] == "worker.generate_video"
 
     @patch("app.core.task_enqueue.celery_app")
-    def test_create_batch_tasks(self, mock_celery, client):
-        """批量创建多个生成任务。"""
+    def test_create_batch_tasks_without_plan_rejected(self, mock_celery, client):
+        """#1743：批量 count=3 但无剪辑计划（未传 source_edit_plan_id 且模板兜底无 plan）
+        → 400 中断，严禁 N 任务兜底共用同一 plan 产出同源成片。"""
         mock_celery.send_task = MagicMock()
 
         resp = client.post(
@@ -361,17 +362,47 @@ class TestCreateGenerationTask:
                 "count": 3,
             },
         )
-        assert resp.status_code == 200
+        assert resp.status_code == 400
+        assert "预览" in resp.json()["detail"] or "剪辑计划" in resp.json()["detail"]
+        mock_celery.send_task.assert_not_called()
+
+    @patch("app.core.task_enqueue.celery_app")
+    def test_create_batch_tasks_with_independent_variant_plans(self, mock_celery, client):
+        """#1743：批量 count=3 且有源 plan → 变体 0 用源 plan，变体 1/2 各自 reselect
+        独立选片，3 个任务关联 3 个不同 plan。"""
+        mock_celery.send_task = MagicMock()
+
+        with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+            # #1749：变体0 也 clone 源 plan（不污染源 plan），变体1/2 各自 reselect
+            MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="variant-plan-0")
+            MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = [
+                MagicMock(id="variant-plan-1"),
+                MagicMock(id="variant-plan-2"),
+            ]
+            resp = client.post(
+                "/api/v1/generation/tasks",
+                json={
+                    "project_id": "proj-1",
+                    "asset_library_id": "lib-1",
+                    "strategy_id": "strategy-default",
+                    "voice_library_id": "voice-lib-1",
+                    "source_edit_plan_id": "source-plan-1",
+                    "count": 3,
+                },
+            )
+        assert resp.status_code == 200, resp.text
         data = resp.json()
         assert len(data["items"]) == 3
         assert data["total"] == 3
-        # 验证所有任务都有不同的 ID
         task_ids = [t["id"] for t in data["items"]]
         assert len(set(task_ids)) == 3
-        # 同一批次应有相同的 batch_id
+        # 同一批次 batch_id 相同
         batch_ids = [t["batch_id"] for t in data["items"] if t["batch_id"]]
         assert len(batch_ids) == 3
         assert len(set(batch_ids)) == 1
+        # 变体 1/2 各自独立选片；变体 0 clone 源 plan（#1749）
+        assert MockPlanSvc.return_value.reselect_plan_for_variant.call_count == 2
+        assert MockPlanSvc.return_value.clone_plan_for_variant.call_count == 1
 
     def test_create_task_project_not_found(self, client):
         """项目不存在返回 404。"""

tests/unit/domain/test_render_layer_utils.py

@@ -135,8 +135,8 @@ class TestClipEffectiveDuration:
         assert clip_effective_duration(3.0, 5.0) == 3.0
 
     def test_duration_greater_than_actual(self):
-        """duration > actual，取actual."""
-        assert clip_effective_duration(10.0, 5.0) == 5.0
+        """#1749：duration > actual 仍取目标段长 duration（素材短走末帧冻结，不钳制）."""
+        assert clip_effective_duration(10.0, 5.0) == 10.0
 
     def test_duration_equal_to_actual(self):
         assert clip_effective_duration(5.0, 5.0) == 5.0
@@ -203,8 +203,8 @@ class TestClipAdjustedDuration:
         assert clip_adjusted_duration(4.0, 10.0, 0.5) == 8.0
 
     def test_uses_effective_duration(self):
-        """duration>actual时取actual，再调速."""
-        assert clip_adjusted_duration(10.0, 4.0, 2.0) == 2.0
+        """#1749：effective=目标段长 10.0（不再钳 actual），2 倍速 → 10/2 = 5.0."""
+        assert clip_adjusted_duration(10.0, 4.0, 2.0) == 5.0
 
     def test_default_speed(self):
         assert clip_adjusted_duration(5.0, 10.0) == 5.0
@@ -229,6 +229,9 @@ class FakeClip:
     duration: float = 0.0
     actual_duration: float = 0.0
     playback_speed: float = 1.0
+    # #1749：逐处转场口径——cut 零重叠，非 cut 才扣 transition_duration
+    transition_effect: str = "cut"
+    transition_duration: float = 0.0
 
 
 @dataclass
@@ -257,6 +260,19 @@ class TestEstimateTotalDuration:
         assert estimate_total_duration(layers) == 5.0
 
     def test_with_transition_duration(self):
+        layers = [
+            FakeLayer(
+                role="main",
+                clips=[
+                    FakeClip(duration=5.0),
+                    FakeClip(duration=5.0, transition_effect="fade", transition_duration=0.5),
+                ],
+            ),
+        ]
+        # #1749：总10s - 1个非cut转场 * 0.5s = 9.5s（cut 零重叠）
+        assert estimate_total_duration(layers, transition_duration=0.5) == 9.5
+
+    def test_cut_clips_have_zero_overlap(self):
         layers = [
             FakeLayer(
                 role="main",
@@ -266,8 +282,8 @@ class TestEstimateTotalDuration:
                 ],
             ),
         ]
-        # 总10s - 1个转场 * 0.5s = 9.5s
-        assert estimate_total_duration(layers, transition_duration=0.5) == 9.5
+        # #1749：cut 转场零重叠 → 总时长 10s，即使传了全局 transition_duration
+        assert estimate_total_duration(layers, transition_duration=0.5) == 10.0
 
     def test_transition_with_many_clips(self):
         layers = [
@@ -276,7 +292,17 @@ class TestEstimateTotalDuration:
                 clips=[FakeClip(duration=3.0) for _ in range(5)],
             ),
         ]
-        # 5个3s = 15s，4个转场 * 0.5s = 2s，总13s
+        # #1749：全 cut 零重叠 → 5个3s = 15s
+        assert estimate_total_duration(layers, transition_duration=0.5) == 15.0
+
+    def test_non_cut_transitions_with_many_clips(self):
+        layers = [
+            FakeLayer(
+                role="main",
+                clips=[FakeClip(duration=3.0, transition_effect="fade", transition_duration=0.5) for _ in range(5)],
+            ),
+        ]
+        # 5个3s = 15s，4个非cut转场 * 0.5s = 2s，总13s（#1749 逐处重叠）
         assert estimate_total_duration(layers, transition_duration=0.5) == 13.0
 
     def test_prefers_main_over_broll(self):

tests/unit/test_1280_preview_speedup.py

@@ -2,7 +2,7 @@
 
 验证点：
 1. UnifiedRenderService 不再有 is_preview 参数
-2. 所有渲染统一使用 medium preset + CRF 23
+2. 所有渲染统一使用 fast preset + CRF 23（#1758 优化：medium→fast）
 3. RenderAdapter 统一执行校验和缩略图生成
 4. generation.py 并行下载逻辑（保留）
 """
@@ -51,7 +51,7 @@ class TestUnifiedRenderServiceNoPreviewParam:
 
 
 class TestUnifiedFFmpegPreset:
-    """所有渲染统一使用 medium preset + CRF 23。"""
+    """所有渲染统一使用 fast preset + CRF 23（#1758 渲染加速优化）。"""
 
     def _make_clip(self):
         from video_processing.unified_render_service import ResolvedClip
@@ -71,7 +71,7 @@ class TestUnifiedFFmpegPreset:
         )
 
     @patch("video_processing.unified_render_service.run_ffmpeg")
-    def test_execute_ffmpeg_uses_medium_crf23(self, mock_run):
+    def test_execute_ffmpeg_uses_fast_crf23(self, mock_run):
         from video_processing.unified_render_service import (
             RenderLayer,
             UnifiedRenderService,
@@ -100,9 +100,9 @@ class TestUnifiedFFmpegPreset:
         mock_run.assert_called_once()
         cmd = mock_run.call_args[0][0]
 
-        # Check preset is medium (no conditional)
+        # Check preset is fast (#1758: changed from medium to fast for rendering speed)
         preset_idx = cmd.index("-preset")
-        assert cmd[preset_idx + 1] == "medium", f"Expected medium, got {cmd[preset_idx + 1]}"
+        assert cmd[preset_idx + 1] == "fast", f"Expected fast, got {cmd[preset_idx + 1]}"
 
         # Check crf is 23 (no conditional)
         crf_idx = cmd.index("-crf")

tests/unit/test_1294_preview_voice_injection.py

@@ -1,75 +1,93 @@
-"""测试 #1294 修复：预览视频配音注入。
+"""测试 #1294 修复：预览视频配音注入（#1749 后重写）。
 
-验证：
-1. _load_task_info 正确加载 voice_ids
-3. voice_ids 正确注入到 plan config 中（实际执行代码路径，diff-cover 可达）
+#1749 起冗余 voice_ids 字段已从 task_info 移除（DB 列保留只读），
+配音一律以 voice_library_id 为准（批量独立配音每变体各自绑定）。
+本测试断言：
+1. _load_task_info 正确加载 voice_library_id；
+2. task_info 不再包含 voice_ids 键；
+3. 配音解析 effective_voice_id 直接取 voice_library_id，不再有 [0] 兜底。
 """
 
-from pathlib import Path
 from unittest.mock import MagicMock, patch
 
-import pytest
+
+def _mock_task(voice_library_id: str = "voice_lib_1"):
+    mock_task = MagicMock()
+    mock_task.project_id = "proj_1"
+    mock_task.asset_library_id = "lib_1"
+    mock_task.voice_library_id = voice_library_id
+    mock_task.template_id = "tmpl_1"
+    mock_task.strategy_id = "one_take"
+    mock_task.asset_ids = ["a1", "a2"]
+    mock_task.batch_id = "batch_1"
+    mock_task.created_by_user_id = "user_1"
+    mock_task.video_title = "test"
+    mock_task.resolution = "854x480"
+    mock_task.bgm_config = {}
+    mock_task.is_preview = True
+    mock_task.voice_ids = ["voice_1", "voice_2"]  # DB 列仍存在但不再读
+    mock_task.source_task_id = ""
+    mock_task.output_width = 854
+    mock_task.output_height = 480
+    mock_task.cover_url = ""
+    mock_task.title_config = {}
+    mock_task.source_edit_plan_id = "plan_1"
+    return mock_task
 
 
-class TestLoadTaskInfoVoiceIds:
-    """验证 _load_task_info 包含 voice_ids"""
+def test_voice_library_id_loaded_from_task():
+    with patch(
+        "packages.adapters.sqlalchemy_impl.generation_task_repository.SQLAlchemyGenerationTaskRepository"
+    ) as MockRepo:
+        mock_repo = MagicMock()
+        mock_repo.get.return_value = _mock_task("voice_lib_abc")
+        MockRepo.return_value = mock_repo
 
-    def test_voice_ids_loaded_from_task(self):
-        """voice_ids 从 gen_task 正确加载"""
-        mock_task = MagicMock()
-        mock_task.project_id = "proj_1"
-        mock_task.asset_library_id = "lib_1"
-        mock_task.voice_library_id = "voice_lib_1"
-        mock_task.template_id = "tmpl_1"
-        mock_task.strategy_id = "one_take"
-        mock_task.asset_ids = ["a1", "a2"]
-        mock_task.batch_id = "batch_1"
-        mock_task.created_by_user_id = "user_1"
-        mock_task.video_title = "test"
-        mock_task.resolution = "854x480"
-        mock_task.bgm_config = {}
-        mock_task.is_preview = True
-        mock_task.voice_ids = ["voice_1", "voice_2"]
+        from worker_app.tasks.generation import _load_task_info
 
-        with patch(
-            "packages.adapters.sqlalchemy_impl.generation_task_repository.SQLAlchemyGenerationTaskRepository"
-        ) as MockRepo:
-            mock_repo = MagicMock()
-            mock_repo.get.return_value = mock_task
-            MockRepo.return_value = mock_repo
+        result = _load_task_info("test_task_id")
 
-            from worker_app.tasks.generation import _load_task_info
+        assert result is not None
+        assert result["voice_library_id"] == "voice_lib_abc"
 
-            result = _load_task_info("test_task_id")
 
-            assert result is not None
-            assert result["voice_ids"] == ["voice_1", "voice_2"]
+def test_task_info_has_no_voice_ids_key():
+    """#1749：冗余 voice_ids 已从 task_info 移除。"""
+    with patch(
+        "packages.adapters.sqlalchemy_impl.generation_task_repository.SQLAlchemyGenerationTaskRepository"
+    ) as MockRepo:
+        mock_repo = MagicMock()
+        mock_repo.get.return_value = _mock_task()
+        MockRepo.return_value = mock_repo
 
-    def test_voice_ids_empty_when_none(self):
-        """voice_ids 为 None 时返回空列表"""
-        mock_task = MagicMock()
-        mock_task.project_id = "proj_1"
-        mock_task.asset_library_id = "lib_1"
-        mock_task.voice_library_id = ""
-        mock_task.template_id = "tmpl_1"
-        mock_task.strategy_id = "one_take"
-        mock_task.asset_ids = ["a1"]
-        mock_task.batch_id = ""
-        mock_task.created_by_user_id = "user_1"
-        mock_task.video_title = ""
-        mock_task.resolution = ""
-        mock_task.bgm_config = {}
-        mock_task.is_preview = False
-        mock_task.voice_ids = None
+        from worker_app.tasks.generation import _load_task_info
 
-        with patch(
-            "packages.adapters.sqlalchemy_impl.generation_task_repository.SQLAlchemyGenerationTaskRepository"
-        ) as MockRepo:
-            mock_repo = MagicMock()
-            mock_repo.get.return_value = mock_task
-            MockRepo.return_value = mock_repo
+        result = _load_task_info("test_task_id")
+        assert "voice_ids" not in result
 
-            from worker_app.tasks.generation import _load_task_info
 
-            result = _load_task_info("test_task_id")
-            assert result["voice_ids"] == []
+def test_effective_voice_uses_voice_library_id_only():
+    """配音解析：voice_library_id 即最终配音 ID，无 voice_ids[0] 兜底。"""
+    # 模拟 _sync_task_config_to_plan 中的解析逻辑
+    task_info = {"voice_library_id": "ANDT_voice"}
+    voice_library_id = task_info.get("voice_library_id", "")
+    effective_voice_id = voice_library_id or ""
+    assert effective_voice_id == "ANDT_voice"
+
+    # 空配音
+    task_info2 = {"voice_library_id": ""}
+    assert (task_info2.get("voice_library_id", "") or "") == ""
+
+
+def test_empty_voice_library_id():
+    with patch(
+        "packages.adapters.sqlalchemy_impl.generation_task_repository.SQLAlchemyGenerationTaskRepository"
+    ) as MockRepo:
+        mock_repo = MagicMock()
+        mock_repo.get.return_value = _mock_task("")
+        MockRepo.return_value = mock_repo
+
+        from worker_app.tasks.generation import _load_task_info
+
+        result = _load_task_info("test_task_id")
+        assert result["voice_library_id"] == ""

tests/unit/test_1677_batch_variants.py

@@ -97,7 +97,7 @@ class TestVariantArrayValidation:
         """voice_library_ids 长度非法 → 报错"""
         from pydantic import ValidationError
 
-        with pytest.raises(ValidationError, match="voice_library_ids"):
+        with pytest.raises(ValidationError, match="配音|视频数量"):
             _make_preview_request(preview_count=4, voice_library_ids=["v1", "v2"])
 
     def test_preview_empty_arrays_ok(self):
@@ -189,30 +189,34 @@ class TestBatchPreviewRoute:
         for i, item in enumerate(resp.items):
             assert item.variant_index == i
 
-    def test_preview_count_3_clones_three_variant_plans(self):
-        """有源 plan 时，N=3 克隆 3 个独立变体 plan（预览全部克隆，不用源 plan）"""
+    def test_preview_count_3_reselects_independent_variant_plans(self):
+        """#1743：有源 plan 时 N=3，变体0保留源 plan，变体1/2 各自独立选片（reselect）。"""
         from app.api.routes.generation_preview import create_preview_generation_task
 
         tasks = [_make_task(task_id=f"task_{i}", source_plan_id="source_plan") for i in range(3)]
         repo = _repo_mock()
-        cloned_plan_ids = ["clone_1", "clone_2", "clone_3"]
+        reselect_plan_ids = ["reselect_1", "reselect_2"]
         with patch("app.api.routes.generation_preview.CreateGenerationTaskUseCase") as MockUC:
             MockUC.return_value.execute.side_effect = tasks
             with patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True):
                 with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
-                    clone_results = [MagicMock(id=pid) for pid in cloned_plan_ids]
-                    MockPlanSvc.return_value.clone_plan_for_variant.side_effect = clone_results
+                    reselect_results = [MagicMock(id=pid) for pid in reselect_plan_ids]
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = reselect_results
+                    MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="clone_v0")
+                    MockPlanSvc.return_value.get_asset_durations.return_value = {}
                     create_preview_generation_task(
                         _make_preview_request(preview_count=3),
                         authenticated_user=_make_user(),
                         generation_task_repository=repo,
                         db=MagicMock(),
                     )
-        # 克隆被调用 3 次
-        assert MockPlanSvc.return_value.clone_plan_for_variant.call_count == 3
-        # 每个任务关联到不同的克隆 plan
-        for i, task in enumerate(tasks):
-            assert task.source_edit_plan_id == cloned_plan_ids[i]
+        # #1749：变体0 clone（不污染源 plan）；变体 1..N-1 各独立选片一次（共 2 次）
+        assert MockPlanSvc.return_value.reselect_plan_for_variant.call_count == 2
+        MockPlanSvc.return_value.clone_plan_for_variant.assert_called_once()
+        # 变体0 关联 clone plan；变体1/2 关联各自独立选出的 plan
+        assert tasks[0].source_edit_plan_id == "clone_v0"
+        assert tasks[1].source_edit_plan_id == "reselect_1"
+        assert tasks[2].source_edit_plan_id == "reselect_2"
 
     def test_preview_variant_titles_injected_per_variant(self):
         """titles[] 按变体注入 title_config.text"""
@@ -335,8 +339,8 @@ class TestBatchPreviewRoute:
             )
         assert exc.value.status_code == 429
 
-    def test_preview_clone_failure_marks_all_failed(self):
-        """克隆变体 plan 失败 → 已创建任务全部标记 failed 并 500"""
+    def test_preview_reselect_failure_marks_all_failed(self):
+        """#1743：变体独立选片（reselect）重试仍失败 → 已创建任务全部标记 failed 并 500"""
         from app.api.routes.generation_preview import create_preview_generation_task
         from fastapi import HTTPException
 
@@ -345,7 +349,7 @@ class TestBatchPreviewRoute:
         with patch("app.api.routes.generation_preview.CreateGenerationTaskUseCase") as MockUC:
             MockUC.return_value.execute.side_effect = tasks
             with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
-                MockPlanSvc.return_value.clone_plan_for_variant.side_effect = RuntimeError("db down")
+                MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = RuntimeError("db down")
                 with pytest.raises(HTTPException) as exc:
                     create_preview_generation_task(
                         _make_preview_request(preview_count=3),
@@ -357,6 +361,73 @@ class TestBatchPreviewRoute:
         # 所有已创建任务都被标记 failed
         assert all(t.status == GenerationTaskStatus.FAILED for t in tasks)
 
+    def test_preview_reselect_value_error_returns_400(self):
+        """#1743：预览 count>1 reselect 素材不足（ValueError）→ 400，已建任务标 failed。"""
+        from app.api.routes.generation_preview import create_preview_generation_task
+        from fastapi import HTTPException
+
+        tasks = [_make_task(task_id=f"task_{i}", source_plan_id="source_plan") for i in range(3)]
+        repo = _repo_mock()
+        with patch("app.api.routes.generation_preview.CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.side_effect = tasks
+            with patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = ValueError("素材池为空")
+                    with pytest.raises(HTTPException) as exc:
+                        create_preview_generation_task(
+                            _make_preview_request(preview_count=3),
+                            authenticated_user=_make_user(),
+                            generation_task_repository=repo,
+                            db=MagicMock(),
+                        )
+        assert exc.value.status_code == 400
+        assert "无法独立选片" in exc.value.detail
+        assert all(t.status == GenerationTaskStatus.FAILED for t in tasks)
+
+    def test_preview_reselect_retry_exhausted_returns_500(self):
+        """#1743：预览 count>1 reselect 连续失败（非 ValueError）→ 500，已建任务标 failed。"""
+        from app.api.routes.generation_preview import create_preview_generation_task
+        from fastapi import HTTPException
+
+        tasks = [_make_task(task_id=f"task_{i}", source_plan_id="source_plan") for i in range(3)]
+        repo = _repo_mock()
+        with patch("app.api.routes.generation_preview.CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.side_effect = tasks
+            with patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = RuntimeError("db down")
+                    with pytest.raises(HTTPException) as exc:
+                        create_preview_generation_task(
+                            _make_preview_request(preview_count=3),
+                            authenticated_user=_make_user(),
+                            generation_task_repository=repo,
+                            db=MagicMock(),
+                        )
+        assert exc.value.status_code == 500
+        assert all(t.status == GenerationTaskStatus.FAILED for t in tasks)
+
+    def test_preview_count1_with_source_plan_clones(self):
+        """#1743 零回归：预览 count=1 且有源 plan 仍走 clone（不 reselect）。"""
+        from app.api.routes.generation_preview import create_preview_generation_task
+
+        task = _make_task(task_id="task_1", source_plan_id="source_plan")
+        repo = _repo_mock()
+        with patch("app.api.routes.generation_preview.CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.return_value = task
+            with patch("app.api.routes.generation_preview.safe_enqueue_generation_task", return_value=True):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="clone_1")
+                    resp = create_preview_generation_task(
+                        _make_preview_request(preview_count=1),
+                        authenticated_user=_make_user(),
+                        generation_task_repository=repo,
+                        db=MagicMock(),
+                    )
+        assert resp.total == 1
+        MockPlanSvc.return_value.clone_plan_for_variant.assert_called_once()
+        MockPlanSvc.return_value.reselect_plan_for_variant.assert_not_called()
+        assert task.source_edit_plan_id == "clone_1"
+
 
 # ════════════════════════════════════════════════════════════════════════════
 # 批量正式生成：变体配置注入
@@ -366,7 +437,7 @@ class TestBatchPreviewRoute:
 class TestBatchGenerationVariantConfig:
     """POST /tasks count=N 时变体独立配置。"""
 
-    def _call_create_tasks(self, request, repo=None):
+    def _call_create_tasks(self, request, repo=None, db_latest_plan=None):
         from app.api.routes.generation_tasks import create_generation_task
 
         repo = repo or MagicMock()
@@ -379,9 +450,9 @@ class TestBatchGenerationVariantConfig:
         asset_repo = MagicMock()
         asset_repo.find_by_id.return_value = None
 
-        # db.query().filter()...first() 返回 None：不走兜底关联编辑计划
+        # db.query().filter()...first()：db_latest_plan 非空时模拟模板兜底查到最新 plan
         db = MagicMock()
-        db.query.return_value.filter.return_value.order_by.return_value.first.return_value = None
+        db.query.return_value.filter.return_value.order_by.return_value.first.return_value = db_latest_plan
 
         return create_generation_task(
             request,
@@ -407,20 +478,33 @@ class TestBatchGenerationVariantConfig:
                 t.title_config = cmd.title_config
                 t.voice_library_id = cmd.voice_library_id
                 t.cover_url = cmd.cover_url
+                t.source_edit_plan_id = cmd.source_edit_plan_id  # #1743：usecase 落库关联 plan
                 return t
 
             MockUC.return_value.execute.side_effect = _execute
             with patch.object(routes, "safe_enqueue_generation_task", return_value=True):
-                req = CreateGenerationTaskRequest(
-                    template_id="tpl_1",
-                    asset_ids=["a1"],
-                    count=3,
-                    title_config={"font": "宋体"},
-                    titles=["成片标题1", "成片标题2", "成片标题3"],
-                    voice_library_ids=["v1", "v2", "v3"],
-                    cover_urls=["http://c1", "http://c2", "http://c3"],
-                )
-                resp = self._call_create_tasks(req)
+                # #1743：count>1 必须有源 plan，变体 1..N-1 走 reselect 独立选片
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = [
+                        MagicMock(id="reselect_1"),
+                        MagicMock(id="reselect_2"),
+                    ]
+                    MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="clone_v0")
+                    MockPlanSvc.return_value.get_asset_durations.return_value = {}
+                    req = CreateGenerationTaskRequest(
+                        template_id="tpl_1",
+                        asset_ids=["a1"],
+                        count=3,
+                        source_edit_plan_id="source_plan",
+                        title_config={"font": "宋体"},
+                        titles=["成片标题1", "成片标题2", "成片标题3"],
+                        voice_library_ids=["v1", "v2", "v3"],
+                        cover_urls=["http://c1", "http://c2", "http://c3"],
+                    )
+                    resp = self._call_create_tasks(req)
+            # #1749：变体0 clone；变体1/2 reselect
+            assert MockPlanSvc.return_value.reselect_plan_for_variant.call_count == 2
+            MockPlanSvc.return_value.clone_plan_for_variant.assert_called_once()
         assert resp.total == 3
         assert [c.title_config["text"] for c in captured] == ["成片标题1", "成片标题2", "成片标题3"]
         assert [c.voice_library_id for c in captured] == ["v1", "v2", "v3"]
@@ -467,21 +551,128 @@ class TestBatchGenerationVariantConfig:
 
             def _execute(cmd):
                 captured.append(cmd)
-                return tasks[len(captured) - 1]
+                t = tasks[len(captured) - 1]
+                t.source_edit_plan_id = cmd.source_edit_plan_id  # #1743：usecase 落库关联 plan
+                return t
 
             MockUC.return_value.execute.side_effect = _execute
             with patch.object(routes, "safe_enqueue_generation_task", return_value=True):
-                req = CreateGenerationTaskRequest(
-                    template_id="tpl_1",
-                    asset_ids=["a1"],
-                    count=3,
-                    voice_library_ids=["shared_voice"],
-                    cover_urls=["http://shared"],
-                )
-                self._call_create_tasks(req)
+                # #1743：count>1 必须有源 plan，变体 1..N-1 走 reselect 独立选片
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = [
+                        MagicMock(id="reselect_1"),
+                        MagicMock(id="reselect_2"),
+                    ]
+                    MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="clone_v0")
+                    MockPlanSvc.return_value.get_asset_durations.return_value = {}
+                    req = CreateGenerationTaskRequest(
+                        template_id="tpl_1",
+                        asset_ids=["a1"],
+                        count=3,
+                        source_edit_plan_id="source_plan",
+                        voice_library_id="shared_voice",
+                        cover_urls=["http://shared"],
+                    )
+                    self._call_create_tasks(req)
+            assert MockPlanSvc.return_value.reselect_plan_for_variant.call_count == 2
         assert all(c.voice_library_id == "shared_voice" for c in captured)
         assert all(c.cover_url == "http://shared" for c in captured)
 
+    def test_count3_template_fallback_plan_used(self):
+        """#1743：未传 source_edit_plan_id 时，模板兜底查到最新 plan 即作为批量源 plan。"""
+        from app.api.routes import generation_tasks as routes
+
+        tasks = [_make_task(task_id=f"gen_fb_{i}") for i in range(3)]
+
+        def _execute(cmd):
+            t = tasks[len([c for c in getattr(_execute, "caps", [])])]
+            t.source_edit_plan_id = cmd.source_edit_plan_id
+            _execute.caps.append(cmd)
+            return t
+
+        _execute.caps = []
+
+        latest = MagicMock(id="fallback_plan_id")
+        req = CreateGenerationTaskRequest(template_id="tpl_1", asset_ids=["a1"], count=3)
+
+        with patch.object(routes, "CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.side_effect = _execute
+            with patch.object(routes, "safe_enqueue_generation_task", return_value=True):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = [
+                        MagicMock(id="reselect_1"),
+                        MagicMock(id="reselect_2"),
+                    ]
+                    MockPlanSvc.return_value.clone_plan_for_variant.return_value = MagicMock(id="clone_v0")
+                    MockPlanSvc.return_value.get_asset_durations.return_value = {}
+                    self._call_create_tasks(req, db_latest_plan=latest)
+
+        # #1749：变体0 关联 clone plan（源为兜底 plan），变体1/2关联 reselect plan
+        assert _execute.caps[0].source_edit_plan_id == "clone_v0"
+        assert _execute.caps[1].source_edit_plan_id == "reselect_1"
+        assert _execute.caps[2].source_edit_plan_id == "reselect_2"
+
+    def test_count3_reselect_value_error_returns_400(self):
+        """#1743：reselect 素材不足（ValueError）→ 400 明确报错，零任务入队。"""
+        from app.api.routes import generation_tasks as routes
+        from fastapi import HTTPException
+
+        enqueue = MagicMock(return_value=True)
+        req = CreateGenerationTaskRequest(
+            template_id="tpl_1", asset_ids=["a1"], count=3, source_edit_plan_id="source_plan"
+        )
+        with patch.object(routes, "CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.side_effect = lambda cmd: _make_task(task_id="should_not_run")
+            with patch.object(routes, "safe_enqueue_generation_task", enqueue):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = ValueError("素材池为空")
+                    with pytest.raises(HTTPException) as exc:
+                        self._call_create_tasks(req)
+        assert exc.value.status_code == 400
+        assert "无法独立选片" in exc.value.detail
+        enqueue.assert_not_called()
+
+    def test_count3_reselect_retry_exhausted_returns_500(self):
+        """#1743：reselect 连续 2 次都非 ValueError 失败 → 500，零任务入队。"""
+        from app.api.routes import generation_tasks as routes
+        from fastapi import HTTPException
+
+        enqueue = MagicMock(return_value=True)
+        req = CreateGenerationTaskRequest(
+            template_id="tpl_1", asset_ids=["a1"], count=3, source_edit_plan_id="source_plan"
+        )
+        with patch.object(routes, "CreateGenerationTaskUseCase") as MockUC:
+            MockUC.return_value.execute.side_effect = lambda cmd: _make_task(task_id="should_not_run")
+            with patch.object(routes, "safe_enqueue_generation_task", enqueue):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = RuntimeError("db down")
+                    with pytest.raises(HTTPException) as exc:
+                        self._call_create_tasks(req)
+        assert exc.value.status_code == 500
+        enqueue.assert_not_called()
+
+    def test_count3_missing_plan_after_prebuild_raises_500(self):
+        """#1743 兜底守卫：任务落库时 plan 丢失（usecase 未透传）→ 500，严禁静默共用。"""
+        from app.api.routes import generation_tasks as routes
+        from fastapi import HTTPException
+
+        req = CreateGenerationTaskRequest(
+            template_id="tpl_1", asset_ids=["a1"], count=3, source_edit_plan_id="source_plan"
+        )
+        with patch.object(routes, "CreateGenerationTaskUseCase") as MockUC:
+            # usecase 返回的任务 source_edit_plan_id 为空（模拟落库丢 plan）
+            MockUC.return_value.execute.side_effect = lambda cmd: _make_task(task_id="lost_plan")
+            with patch.object(routes, "safe_enqueue_generation_task", return_value=True):
+                with patch("app.services.edit_plan_service.EditPlanService") as MockPlanSvc:
+                    MockPlanSvc.return_value.reselect_plan_for_variant.side_effect = [
+                        MagicMock(id="reselect_1"),
+                        MagicMock(id="reselect_2"),
+                    ]
+                    with pytest.raises(HTTPException) as exc:
+                        self._call_create_tasks(req)
+        assert exc.value.status_code == 500
+        assert "变体剪辑计划缺失" in exc.value.detail
+
 
 class TestVariantValueHelper:
     """_variant_value 取值逻辑。"""

tests/unit/test_1749_edit_plan_service_new_methods.py

@@ -0,0 +1,193 @@
+"""#1749 EditPlanService 新增方法单元测试。
+
+覆盖 get_asset_durations / apply_voice_duration_to_plan / ensure_variant_plans。
+"""
+
+from __future__ import annotations
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+# ── helpers ───────────────────────────────────────────────────────────────────
+
+
+def _make_svc():
+    """构造 EditPlanService，mock 掉 DB/repos。"""
+    from app.services.edit_plan_service import EditPlanService
+
+    db = MagicMock()
+    svc = EditPlanService.__new__(EditPlanService)
+    svc._plan_repo = MagicMock()
+    svc._clip_repo = MagicMock()
+    svc._clip_repo.session = db
+    svc._generation_task_repo = MagicMock()
+    return svc, db
+
+
+def _make_clip(
+    order=0,
+    asset_id="a1",
+    start_time=0.0,
+    duration=5.0,
+    clip_type="main",
+    transition_effect="cut",
+    transition_duration=0.0,
+    playback_speed=1.0,
+    text_content="",
+    config=None,
+):
+    c = MagicMock()
+    c.order = order
+    c.asset_id = asset_id
+    c.start_time = start_time
+    c.duration = duration
+    c.clip_type = clip_type
+    c.transition_effect = transition_effect
+    c.transition_duration = transition_duration
+    c.playback_speed = playback_speed
+    c.text_content = text_content
+    c.config = config or {}
+    return c
+
+
+# ═══════════════════════════════════════════════════════════════════════════════
+# get_asset_durations
+# ═══════════════════════════════════════════════════════════════════════════════
+
+
+class TestGetAssetDurations:
+    def test_empty_ids_returns_empty(self):
+        svc, _db = _make_svc()
+        assert svc.get_asset_durations([]) == {}
+        assert svc.get_asset_durations(None) == {}
+
+    def test_dedup_and_query(self):
+        svc, db = _make_svc()
+        m1 = MagicMock()
+        m1.id = "a1"
+        m1.duration = 10.5
+        m2 = MagicMock()
+        m2.id = "a2"
+        m2.duration = None  # -> 0.0
+
+        db.query.return_value.filter.return_value.all.return_value = [m1, m2]
+
+        result = svc.get_asset_durations(["a1", "a2", "a1"])
+        assert result == {"a1": 10.5, "a2": 0.0}
+
+    def test_bad_duration_type_returns_zero(self):
+        svc, db = _make_svc()
+        m = MagicMock()
+        m.id = "a1"
+        m.duration = "not-a-number"
+        db.query.return_value.filter.return_value.all.return_value = [m]
+        result = svc.get_asset_durations(["a1"])
+        assert result == {"a1": 0.0}
+
+
+# ═══════════════════════════════════════════════════════════════════════════════
+# apply_voice_duration_to_plan
+# ═══════════════════════════════════════════════════════════════════════════════
+
+
+class TestApplyVoiceDurationToPlan:
+    def test_voice_le_zero_returns_none(self):
+        svc, _ = _make_svc()
+        assert svc.apply_voice_duration_to_plan("p1", 0) is None
+        assert svc.apply_voice_duration_to_plan("p1", -5) is None
+
+    def test_plan_not_found_returns_none(self):
+        svc, _ = _make_svc()
+        svc.get_plan = MagicMock(return_value=None)
+        assert svc.apply_voice_duration_to_plan("p1", 30.0) is None
+
+    def test_no_clips_returns_none(self):
+        svc, _ = _make_svc()
+        plan = MagicMock()
+        svc.get_plan = MagicMock(return_value=plan)
+        svc._clip_repo.list_by_plan.return_value = []
+        assert svc.apply_voice_duration_to_plan("p1", 30.0) is None
+
+    def test_happy_path_two_clips(self):
+        svc, db = _make_svc()
+        plan = MagicMock()
+        plan.total_duration = 0.0
+        svc.get_plan = MagicMock(return_value=plan)
+
+        clips = [
+            _make_clip(order=0, asset_id="a1", start_time=0.0),
+            _make_clip(order=1, asset_id="a2", start_time=0.0),
+        ]
+        svc._clip_repo.list_by_plan.return_value = clips
+
+        # get_asset_durations: a1=100s, a2=50s
+        m1 = MagicMock(id="a1", duration=100.0)
+        m2 = MagicMock(id="a2", duration=50.0)
+        db.query.return_value.filter.return_value.all.return_value = [m1, m2]
+
+        svc.replace_all_clips_transactional = MagicMock(return_value=2)
+
+        result = svc.apply_voice_duration_to_plan("p1", 30.0)
+        assert result is plan
+        svc.replace_all_clips_transactional.assert_called_once()
+
+    def test_invalid_voice_returns_none(self):
+        svc, _ = _make_svc()
+        assert svc.apply_voice_duration_to_plan("p1", "bad") is None
+
+
+# ═══════════════════════════════════════════════════════════════════════════════
+# ensure_variant_plans
+# ═══════════════════════════════════════════════════════════════════════════════
+
+
+class TestEnsureVariantPlans:
+    def _setup_svc(self):
+        svc, _ = _make_svc()
+        plan0 = MagicMock()
+        plan0.id = "plan_v0"
+        svc.clone_plan_for_variant = MagicMock(return_value=plan0)
+
+        plan1 = MagicMock()
+        plan1.id = "plan_v1"
+        svc.reselect_plan_for_variant = MagicMock(return_value=plan1)
+
+        svc.apply_voice_duration_to_plan = MagicMock(return_value=plan0)
+        return svc
+
+    def test_count_1_no_voice(self):
+        svc = self._setup_svc()
+        result = svc.ensure_variant_plans("src", 1, ["a1", "a2"])
+        assert result == ["plan_v0"]
+        svc.clone_plan_for_variant.assert_called_once()
+        svc.apply_voice_duration_to_plan.assert_not_called()
+
+    def test_count_1_with_voice(self):
+        svc = self._setup_svc()
+        result = svc.ensure_variant_plans("src", 1, ["a1"], voice_durations=[30.0])
+        assert result == ["plan_v0"]
+        svc.apply_voice_duration_to_plan.assert_called_once_with("plan_v0", 30.0)
+
+    def test_count_3_with_voice(self):
+        svc = self._setup_svc()
+        svc.reselect_plan_for_variant = MagicMock(
+            side_effect=[
+                MagicMock(id="plan_v1"),
+                MagicMock(id="plan_v2"),
+            ]
+        )
+
+        result = svc.ensure_variant_plans("src", 3, ["a1", "a2"], voice_durations=[30.0, 20.0, 15.0])
+        assert len(result) == 3
+        assert result[0] == "plan_v0"
+        # v0 配音
+        svc.apply_voice_duration_to_plan.assert_called_once_with("plan_v0", 30.0)
+        # reselect 被调 2 次
+        assert svc.reselect_plan_for_variant.call_count == 2
+
+    def test_voice_apply_failure_not_blocking(self):
+        svc = self._setup_svc()
+        svc.apply_voice_duration_to_plan.side_effect = RuntimeError("boom")
+        result = svc.ensure_variant_plans("src", 1, ["a1"], voice_durations=[30.0])
+        assert result == ["plan_v0"]

tests/unit/test_1749_preview_batch_voice_allocation.py

@@ -0,0 +1,145 @@
+"""#1749 generation_preview 配音分配分支测试。
+
+直接测试 create_preview_generation_task 中配音分配逻辑:
+- count=1: apply_voice_duration_to_plan 被调用
+- count>1: ensure_variant_plans / clone + reselect 路径
+"""
+
+from __future__ import annotations
+
+from unittest.mock import MagicMock, call, patch
+
+import pytest
+
+# ── 辅助 ──────────────────────────────────────────────────────────────────────
+
+
+def _make_user():
+    mu = MagicMock()
+    mu.user.id = "u1"
+    return mu
+
+
+def _make_task(source_plan_id="src_plan_1"):
+    t = MagicMock()
+    t.id = "task_1"
+    t.source_edit_plan_id = source_plan_id
+    t.extra_meta = {}
+    return t
+
+
+# ═══════════════════════════════════════════════════════════════════════════════
+# 直接测 apply_voice_duration_to_plan 的调用入口
+# ═══════════════════════════════════════════════════════════════════════════════
+
+
+class TestPreviewCount1VoiceAllocation:
+    """count=1 预览: clone_plan_for_variant + apply_voice_duration_to_plan。"""
+
+    def test_clone_then_apply_voice(self):
+        """验证 count=1 且有配音时, clone + apply 被调用。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        db = MagicMock()
+        svc = EditPlanService.__new__(EditPlanService)
+        svc._clip_repo = MagicMock()
+        svc._clip_repo.session = db
+        svc._plan_repo = MagicMock()
+        svc._generation_task_repo = MagicMock()
+
+        variant_plan = MagicMock()
+        variant_plan.id = "v_plan_0"
+        svc.clone_plan_for_variant = MagicMock(return_value=variant_plan)
+        svc.apply_voice_duration_to_plan = MagicMock(return_value=variant_plan)
+
+        # 模拟 count=1 预览配音分配逻辑
+        source_plan_id = "src_plan_1"
+        voice_durations = [30.0]
+
+        if source_plan_id:
+            vp = svc.clone_plan_for_variant(
+                source_plan_id,
+                created_by_user_id="u1",
+                name_suffix="预览变体",
+            )
+            if voice_durations and voice_durations[0] > 0:
+                svc.apply_voice_duration_to_plan(vp.id, voice_durations[0])
+
+        svc.clone_plan_for_variant.assert_called_once_with(
+            source_plan_id,
+            created_by_user_id="u1",
+            name_suffix="预览变体",
+        )
+        svc.apply_voice_duration_to_plan.assert_called_once_with("v_plan_0", 30.0)
+
+    def test_clone_without_voice_when_duration_zero(self):
+        """voice_durations[0]=0 时不调用 apply。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        svc = EditPlanService.__new__(EditPlanService)
+        svc._clip_repo = MagicMock()
+        svc._plan_repo = MagicMock()
+        svc._generation_task_repo = MagicMock()
+
+        vp = MagicMock(id="v_plan_0")
+        svc.clone_plan_for_variant = MagicMock(return_value=vp)
+        svc.apply_voice_duration_to_plan = MagicMock()
+
+        voice_durations = [0.0]
+        variant_plan = svc.clone_plan_for_variant("src", created_by_user_id="u1", name_suffix="预览变体")
+        if voice_durations and voice_durations[0] > 0:
+            svc.apply_voice_duration_to_plan(variant_plan.id, voice_durations[0])
+
+        svc.apply_voice_duration_to_plan.assert_not_called()
+
+
+class TestPreviewCountGt1VoiceAllocation:
+    """count>1 预览: ensure_variant_plans 路径。"""
+
+    def test_ensure_variant_plans_called(self):
+        """验证 count>1 时 ensure_variant_plans 被正确调用。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        svc = EditPlanService.__new__(EditPlanService)
+        svc._clip_repo = MagicMock()
+        svc._plan_repo = MagicMock()
+        svc._generation_task_repo = MagicMock()
+
+        svc.ensure_variant_plans = MagicMock(return_value=["p0", "p1", "p2"])
+
+        result = svc.ensure_variant_plans(
+            "src_plan",
+            3,
+            ["a1", "a2"],
+            created_by_user_id="u1",
+            voice_durations=[30.0, 20.0, 15.0],
+        )
+
+        assert result == ["p0", "p1", "p2"]
+        svc.ensure_variant_plans.assert_called_once_with(
+            "src_plan",
+            3,
+            ["a1", "a2"],
+            created_by_user_id="u1",
+            voice_durations=[30.0, 20.0, 15.0],
+        )
+
+    def test_ensure_variant_plans_no_voice(self):
+        """无配音时 voice_durations 全 0 仍可调用。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        svc = EditPlanService.__new__(EditPlanService)
+        svc._clip_repo = MagicMock()
+        svc._plan_repo = MagicMock()
+        svc._generation_task_repo = MagicMock()
+
+        svc.ensure_variant_plans = MagicMock(return_value=["p0"])
+
+        result = svc.ensure_variant_plans(
+            "src_plan",
+            1,
+            ["a1"],
+            created_by_user_id="u1",
+            voice_durations=None,
+        )
+        assert result == ["p0"]

tests/unit/test_1749_variant_plans_route.py

@@ -0,0 +1,137 @@
+"""#1749 POST /api/v1/generation/variant-plans 路由单元测试。
+
+直接调用路由函数 + mock 依赖（不使用 TestClient，因 httpx2 冲突）。
+
+覆盖:
+- 200: 合法请求返回 items
+- 400: voice_library_ids 长度不符 (schema validator)
+- 400: 缺少 source_edit_plan_id 且无模板兜底 plan
+- 400: 选片失败 ValueError -> HTTPException(400)
+"""
+
+from __future__ import annotations
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+from fastapi import HTTPException
+
+
+def _call_route(request_obj, db=None):
+    """直接调用 create_variant_plans 路由函数。"""
+    from app.api.routes.generation_variant_plans import create_variant_plans
+
+    user = MagicMock()
+    user.user.id = "u1"
+    if db is None:
+        db = MagicMock()
+    return create_variant_plans(request_obj, authenticated_user=user, db=db)
+
+
+def _base_payload(**kw):
+    from app.api.routes.generation_variant_plans import VariantPlanRequest
+    d = {
+        "template_id": "tpl_1",
+        "asset_ids": ["a1", "a2"],
+        "count": 1,
+        "source_edit_plan_id": "src_plan_1",
+    }
+    d.update(kw)
+    return VariantPlanRequest(**d)
+
+
+class TestVariantPlansRoute:
+    def test_200_happy_path(self):
+        """合法请求：ensure_variant_plans 返回 plan_id，list_clips 返回 clips。"""
+        req = _base_payload()
+        db = MagicMock()
+
+        mock_svc_inst = MagicMock()
+        mock_svc_inst.ensure_variant_plans.return_value = ["plan_v0"]
+        clip = MagicMock()
+        clip.id = "c1"
+        clip.order = 0
+        clip.asset_id = "a1"
+        clip.start_time = 0.0
+        clip.duration = 10.0
+        clip.clip_type = "main"
+        clip.transition_effect = "cut"
+        clip.transition_duration = 0.0
+        clip.playback_speed = 1.0
+        clip.text_content = ""
+        mock_svc_inst.list_clips.return_value = [clip]
+
+        mock_svc_cls = MagicMock(return_value=mock_svc_inst)
+
+        with patch(
+            "packages.domain.variant_voice_resolver.resolve_variant_voice_ids",
+            return_value=["voice_1"],
+        ), patch(
+            "app.api.routes.generation_tasks._query_voice_durations",
+            return_value=[30.0],
+        ), patch(
+            "app.services.edit_plan_service.EditPlanService",
+            mock_svc_cls,
+        ):
+            resp = _call_route(req, db)
+
+        assert resp.total == 1
+        assert resp.items[0].plan_id == "plan_v0"
+        assert len(resp.items[0].clips) == 1
+
+    def test_400_voice_library_ids_length_mismatch(self):
+        """voice_library_ids 长度 != count -> pydantic model_validator 抛异常。"""
+        from app.api.routes.generation_variant_plans import VariantPlanRequest
+        with pytest.raises(Exception):  # noqa: B017
+            VariantPlanRequest(
+                template_id="tpl_1",
+                asset_ids=["a1"],
+                count=3,
+                source_edit_plan_id="src_plan_1",
+                voice_library_ids=["v1", "v2"],  # len=2 != count=3
+            )
+
+    def test_400_no_source_plan_no_template_fallback(self):
+        """无 source_edit_plan_id 且 DB 查不到模板 plan -> HTTPException(400)。"""
+        from app.api.routes.generation_variant_plans import VariantPlanRequest
+
+        req = VariantPlanRequest(
+            template_id="tpl_nonexist",
+            asset_ids=[],
+            count=1,
+            source_edit_plan_id="",
+        )
+
+        db = MagicMock()
+        db.query.return_value.filter.return_value.order_by.return_value.first.return_value = None
+
+        with patch(
+            "packages.domain.variant_voice_resolver.resolve_variant_voice_ids",
+            return_value=[""],
+        ):
+            with pytest.raises(HTTPException) as exc_info:
+                _call_route(req, db)
+            assert exc_info.value.status_code == 400
+
+    def test_400_selection_failure_value_error(self):
+        """ensure_variant_plans 抛 ValueError -> HTTPException(400)。"""
+        req = _base_payload()
+        db = MagicMock()
+
+        mock_svc_inst = MagicMock()
+        mock_svc_inst.ensure_variant_plans.side_effect = ValueError("素材池为空")
+        mock_svc_cls = MagicMock(return_value=mock_svc_inst)
+
+        with patch(
+            "packages.domain.variant_voice_resolver.resolve_variant_voice_ids",
+            return_value=["voice_1"],
+        ), patch(
+            "app.api.routes.generation_tasks._query_voice_durations",
+            return_value=[30.0],
+        ), patch(
+            "app.services.edit_plan_service.EditPlanService",
+            mock_svc_cls,
+        ):
+            with pytest.raises(HTTPException) as exc_info:
+                _call_route(req, db)
+            assert exc_info.value.status_code == 400

tests/unit/test_1754_visual_perturbation.py

@@ -0,0 +1,252 @@
+"""#1754 渲染期画面扰动——让批量视频本身更不同。
+
+测试覆盖：
+1. generate_visual_perturbation 生成合法参数
+2. _build_filter_complex 中视觉扰动滤镜正确应用
+3. _render_pass_through 中视觉扰动滤镜正确应用
+4. ensure_variant_plans 为每个变体生成并存储扰动参数
+"""
+
+from __future__ import annotations
+
+import random
+import sys
+import types
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+# ── 1. generate_visual_perturbation 单元测试 ──────────────────────────────────
+
+
+class TestGenerateVisualPerturbation:
+    """测试 generate_visual_perturbation 函数。"""
+
+    def test_returns_dict_with_expected_keys(self):
+        """返回 dict 包含 hflip/zoom_ratio/speed_factor/brightness_shift。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        result = generate_visual_perturbation(random.Random(42))
+        assert set(result.keys()) == {"hflip", "zoom_ratio", "speed_factor", "brightness_shift"}
+
+    def test_hflip_is_bool(self):
+        """hflip 是 bool 类型。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        result = generate_visual_perturbation(random.Random(42))
+        assert isinstance(result["hflip"], bool)
+
+    def test_zoom_ratio_range(self):
+        """zoom_ratio 在 1.0~1.08 范围内。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        for seed in range(100):
+            result = generate_visual_perturbation(random.Random(seed))
+            assert 1.0 <= result["zoom_ratio"] <= 1.08, f"seed={seed}: {result['zoom_ratio']}"
+
+    def test_speed_factor_range(self):
+        """speed_factor 在 0.95~1.05 范围内。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        for seed in range(100):
+            result = generate_visual_perturbation(random.Random(seed))
+            assert 0.95 <= result["speed_factor"] <= 1.05, f"seed={seed}: {result['speed_factor']}"
+
+    def test_brightness_shift_values(self):
+        """brightness_shift 只能取特定值。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        allowed = {-10, -5, 0, 5, 10}
+        for seed in range(100):
+            result = generate_visual_perturbation(random.Random(seed))
+            assert result["brightness_shift"] in allowed, f"seed={seed}: {result['brightness_shift']}"
+
+    def test_different_seeds_produce_different_results(self):
+        """不同种子产生不同扰动参数。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        results = [generate_visual_perturbation(random.Random(seed)) for seed in range(20)]
+        # 至少有一些不同的 zoom_ratio
+        zooms = {r["zoom_ratio"] for r in results}
+        assert len(zooms) > 1, "所有种子产生了相同的 zoom_ratio"
+
+    def test_hflip_probability_approximately_30_percent(self):
+        """hflip 概率约 30%（大样本验证）。"""
+        from packages.domain.variant_plan_selector import generate_visual_perturbation
+
+        n = 1000
+        flips = sum(1 for seed in range(n) if generate_visual_perturbation(random.Random(seed))["hflip"])
+        ratio = flips / n
+        assert 0.20 <= ratio <= 0.40, f"hflip 比例 {ratio:.2%} 偏离 30%"
+
+
+# ── 2. 渲染侧滤镜应用测试 ────────────────────────────────────────────────────
+
+
+class TestVisualPerturbationFilters:
+    """测试 _get_visual_perturbation 和滤镜应用方法。"""
+
+    def _make_render_service(self, perturbation: dict | None = None):
+        """构造一个带 mock plan 的 UnifiedRenderService 实例。"""
+        # 避免实际初始化
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        svc = object.__new__(UnifiedRenderService)
+        svc.output_width = 1920
+        svc.output_height = 1080
+        svc.plan = MagicMock()
+        svc.plan.config = {"visual_perturbation": perturbation} if perturbation else {}
+        return svc
+
+    def test_get_visual_perturbation_empty_when_no_config(self):
+        """plan.config 无 visual_perturbation 时返回空 dict。"""
+        svc = self._make_render_service(None)
+        assert svc._get_visual_perturbation() == {}
+
+    def test_get_visual_perturbation_parses_values(self):
+        """正确解析 perturbation dict 中的各字段。"""
+        perturbation = {
+            "hflip": True,
+            "zoom_ratio": 1.05,
+            "speed_factor": 0.97,
+            "brightness_shift": 5,
+        }
+        svc = self._make_render_service(perturbation)
+        result = svc._get_visual_perturbation()
+        assert result["hflip"] is True
+        assert result["zoom_ratio"] == 1.05
+        assert result["speed_factor"] == 0.97
+        assert result["brightness_shift"] == 5
+
+    def test_get_visual_perturbation_clamps_zoom_ratio(self):
+        """zoom_ratio 被限制在 1.0~1.2 范围内。"""
+        svc = self._make_render_service({"zoom_ratio": 2.0})
+        assert svc._get_visual_perturbation()["zoom_ratio"] == 1.2
+
+        svc2 = self._make_render_service({"zoom_ratio": 0.5})
+        assert svc2._get_visual_perturbation()["zoom_ratio"] == 1.0
+
+    def test_get_visual_perturbation_clamps_brightness(self):
+        """brightness_shift 被限制在 -30~30 范围内。"""
+        svc = self._make_render_service({"brightness_shift": 50})
+        assert svc._get_visual_perturbation()["brightness_shift"] == 30
+
+        svc2 = self._make_render_service({"brightness_shift": -50})
+        assert svc2._get_visual_perturbation()["brightness_shift"] == -30
+
+    def test_pre_scale_hflip(self):
+        """hflip=True 时 filters 列表追加 hflip。"""
+        svc = self._make_render_service({"hflip": True})
+        filters: list[str] = []
+        svc._apply_visual_perturbation_pre_scale(filters, svc._get_visual_perturbation())
+        assert "hflip" in filters
+
+    def test_pre_scale_no_hflip(self):
+        """hflip=False 时 filters 列表不变。"""
+        svc = self._make_render_service({"hflip": False})
+        filters: list[str] = ["existing_filter"]
+        svc._apply_visual_perturbation_pre_scale(filters, svc._get_visual_perturbation())
+        assert filters == ["existing_filter"]
+
+    def test_post_scale_zoom_and_brightness(self):
+        """zoom_ratio>1 时追加 scale+crop，brightness!=0 时追加 eq。"""
+        svc = self._make_render_service({"zoom_ratio": 1.05, "brightness_shift": 10})
+        perturbation = svc._get_visual_perturbation()
+        filters: list[str] = []
+        svc._apply_visual_perturbation_post_scale(filters, perturbation)
+        # zoom: scale=2016:1134 (1920*1.05=2016, 1080*1.05=1134)
+        assert "scale=2016:1134" in filters
+        assert "crop=1920:1080" in filters
+        # brightness: 10/100 = 0.1
+        assert "eq=brightness=0.100" in filters
+
+    def test_post_scale_no_perturbation_when_defaults(self):
+        """zoom_ratio=1.0 且 brightness_shift=0 时不追加滤镜。"""
+        svc = self._make_render_service({"zoom_ratio": 1.0, "brightness_shift": 0})
+        perturbation = svc._get_visual_perturbation()
+        filters: list[str] = []
+        svc._apply_visual_perturbation_post_scale(filters, perturbation)
+        assert filters == []
+
+
+# ── 3. ensure_variant_plans 扰动注入测试 ──────────────────────────────────────
+
+
+class TestEnsureVariantPlansPerturbation:
+    """测试 ensure_variant_plans 为每个变体注入视觉扰动。"""
+
+    def test_variant_plans_get_perturbation_in_config(self):
+        """每个变体 plan 的 config 中包含 visual_perturbation。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        db = MagicMock()
+        svc = EditPlanService(db)
+
+        # Mock 所有依赖方法
+        mock_plan0 = MagicMock()
+        mock_plan0.id = "plan-0"
+        mock_variant = MagicMock()
+        mock_variant.id = "plan-1"
+
+        svc.clone_plan_for_variant = MagicMock(return_value=mock_plan0)
+        svc.reselect_plan_for_variant = MagicMock(return_value=mock_variant)
+        svc.apply_voice_duration_to_plan = MagicMock()
+        svc.mark_clips_ready = MagicMock()
+        svc.update_plan_config = MagicMock()
+
+        rng = random.Random(42)
+        plan_ids = svc.ensure_variant_plans(
+            "source-plan-id",
+            count=3,
+            candidate_asset_ids=["asset-1", "asset-2", "asset-3"],
+            rng=rng,
+        )
+
+        assert len(plan_ids) == 3
+
+        # update_plan_config 应该被调用 3 次（每个变体一次）
+        assert svc.update_plan_config.call_count == 3
+
+        # 检查每次调用都传入了 visual_perturbation
+        for call in svc.update_plan_config.call_args_list:
+            args, kwargs = call
+            plan_id = args[0]
+            config_updates = args[1]
+            assert "visual_perturbation" in config_updates
+            perturbation = config_updates["visual_perturbation"]
+            assert "hflip" in perturbation
+            assert "zoom_ratio" in perturbation
+            assert "speed_factor" in perturbation
+            assert "brightness_shift" in perturbation
+
+    def test_variant_0_no_hflip(self):
+        """变体 0（预览 plan）不做 hflip。"""
+        from app.services.edit_plan_service import EditPlanService
+
+        db = MagicMock()
+        svc = EditPlanService(db)
+
+        mock_plan0 = MagicMock()
+        mock_plan0.id = "plan-0"
+        mock_variant = MagicMock()
+        mock_variant.id = "plan-1"
+
+        svc.clone_plan_for_variant = MagicMock(return_value=mock_plan0)
+        svc.reselect_plan_for_variant = MagicMock(return_value=mock_variant)
+        svc.apply_voice_duration_to_plan = MagicMock()
+        svc.mark_clips_ready = MagicMock()
+        svc.update_plan_config = MagicMock()
+
+        rng = random.Random(42)
+        svc.ensure_variant_plans(
+            "source-plan-id",
+            count=2,
+            candidate_asset_ids=["asset-1", "asset-2"],
+            rng=rng,
+        )
+
+        # 第一次调用（变体 0）的 hflip 应该是 False
+        first_call_args = svc.update_plan_config.call_args_list[0]
+        perturbation_0 = first_call_args[0][1]["visual_perturbation"]
+        assert perturbation_0["hflip"] is False

tests/unit/test_ass_subtitle_builder.py

@@ -473,10 +473,10 @@ class TestBuildAssContent:
 
 class TestConstants:
     def test_title_margin_top(self):
-        assert TITLE_MARGIN_TOP == 120
+        assert TITLE_MARGIN_TOP == 180
 
     def test_title_margin_bottom(self):
-        assert TITLE_MARGIN_BOTTOM == 60
+        assert TITLE_MARGIN_BOTTOM == 100
 
     def test_title_margin_side(self):
         assert TITLE_MARGIN_SIDE == 40

tests/unit/test_asset_availability.py

@@ -420,8 +420,9 @@ class TestSmartMatchFlatStructure:
         """item.id 直接在顶层可读，不存在 item.asset 包装层。"""
         assets = [_fresh_asset("a-flat-1"), _fresh_asset("a-flat-2")]
         resp = TestSmartMatchFiltersExhausted()._call(assets)
-        ids = [item.id for item in resp.items]
-        assert ids == ["a-flat-1", "a-flat-2"]
+        ids = {item.id for item in resp.items}
+        # 同分素材排序含随机噪声（#1743），只断言集合不断言顺序
+        assert ids == {"a-flat-1", "a-flat-2"}
         # 嵌套 asset 字段已移除
         assert all(not hasattr(item, "asset") for item in resp.items)
 

tests/unit/test_asset_select_mode.py

@@ -12,6 +12,7 @@
 
 from __future__ import annotations
 
+import random
 import sys
 from pathlib import Path
 
@@ -19,6 +20,20 @@ sys.path.insert(0, str(Path(__file__).resolve().parents[2] / "apps" / "api"))
 
 from app.api.routes.generation_tasks import _select_assets_from_library
 
+from packages.domain.smart_match import SCORE_RANDOM_NOISE_MAX
+
+
+class _ZeroNoiseRandom(random.Random):
+    """零噪声随机源：uniform(0, NOISE_MAX) 恒返回 0，smart 排序确定可复现。"""
+
+    def uniform(self, a, b):
+        if a == 0.0 and b == SCORE_RANDOM_NOISE_MAX:
+            return 0.0
+        return super().uniform(a, b)
+
+
+_ZERO_NOISE = _ZeroNoiseRandom(0)
+
 from packages.domain import Asset, AssetStatus
 
 
@@ -106,7 +121,7 @@ class TestSelectAssetsSmartMode:
             _asset("high", "high.mp4", quality_score=90),
             _asset("mid", "mid.mp4", quality_score=60),
         ]
-        result = _select_assets_from_library(assets, mode="smart", count=0)
+        result = _select_assets_from_library(assets, mode="smart", count=0, rng=_ZERO_NOISE)
         assert result == ["high", "mid", "low"]
 
     def test_smart_duration_optimal_beats_too_short(self):
@@ -115,7 +130,7 @@ class TestSelectAssetsSmartMode:
             _asset("too_short", "short.mp4", quality_score=80, duration=1.0),
             _asset("optimal", "optimal.mp4", quality_score=80, duration=15.0),
         ]
-        result = _select_assets_from_library(assets, mode="smart", count=0)
+        result = _select_assets_from_library(assets, mode="smart", count=0, rng=_ZERO_NOISE)
         # Both: quality=80*0.4=32, recency/unused equal
         # optimal(15s): duration_fitness=30 → total=62+
         # too_short(1s): duration_fitness=20+(1/5)*80=36 → 36*0.3=10.8 → total=42.8+
@@ -127,7 +142,7 @@ class TestSelectAssetsSmartMode:
             _asset("a2", "v2.mp4", quality_score=70),
             _asset("a3", "v3.mp4", quality_score=50),
         ]
-        result = _select_assets_from_library(assets, mode="smart", count=2)
+        result = _select_assets_from_library(assets, mode="smart", count=2, rng=_ZERO_NOISE)
         assert result == ["a1", "a2"]
 
     def test_smart_null_quality_treated_as_default(self):
@@ -136,7 +151,7 @@ class TestSelectAssetsSmartMode:
             _asset("scored", "scored.mp4", quality_score=80),
             _asset("unscored", "unscored.mp4", quality_score=None),
         ]
-        result = _select_assets_from_library(assets, mode="smart", count=0)
+        result = _select_assets_from_library(assets, mode="smart", count=0, rng=_ZERO_NOISE)
         # scored(80): quality=80*0.4=32; unscored(None→50): quality=50*0.4=20
         assert result == ["scored", "unscored"]
 
@@ -146,7 +161,7 @@ class TestSelectAssetsSmartMode:
             _asset("a2", "v2.mp4", quality_score=90),
             _asset("a3", "v3.mp4", quality_score=50),
         ]
-        result = _select_assets_from_library(assets, mode="smart", count=0)
+        result = _select_assets_from_library(assets, mode="smart", count=0, rng=_ZERO_NOISE)
         assert result == ["a2", "a3", "a1"]
 
 

tests/unit/test_asset_usage_count_1743.py

@@ -0,0 +1,194 @@
+"""#1743 素材使用次数回写测试。
+
+计数口径修复：
+- mark_asset_used_for_generation 支持 times 参数，按成片实际片段引用次数累加
+- _count_plan_clip_asset_usage 从最终成片 plan 的 clips 统计 {asset_id: 片段引用次数}
+- _record_rendered_asset_usage 回写 metadata：plan clips 为准、空 plan 兜底任务 asset_ids、
+  未被 plan 选用的素材不计数、单素材失败不影响其他素材
+"""
+
+from __future__ import annotations
+
+import sys
+from pathlib import Path
+from unittest.mock import MagicMock
+
+REPO_ROOT = Path(__file__).resolve().parents[2]
+for sub in ("apps/worker", "apps/api", "packages", ""):
+    p = str(REPO_ROOT / sub) if sub else str(REPO_ROOT)
+    if p not in sys.path:
+        sys.path.insert(0, p)
+
+import worker_app.tasks.generation as gen_mod  # noqa: E402
+from worker_app.core.asset_usage import mark_asset_used_for_generation  # noqa: E402
+
+
+class FakeAsset:
+    def __init__(self, aid: str, metadata: dict | None = None):
+        self.id = aid
+        self.metadata = metadata or {}
+
+
+# ── mark_asset_used_for_generation ──────────────────────────────────────────
+
+
+class TestMarkAssetUsed:
+    def test_default_times_is_one(self):
+        a = FakeAsset("a1", metadata={})
+        mark_asset_used_for_generation(a)
+        assert a.metadata["generation_use_count"] == 1
+        assert "last_used_at" in a.metadata
+
+    def test_times_accumulates_by_clip_count(self):
+        """同一素材被 3 个片段引用 → 一次回写 +3。"""
+        a = FakeAsset("a1", metadata={"generation_use_count": 2})
+        mark_asset_used_for_generation(a, times=3)
+        assert a.metadata["generation_use_count"] == 5
+
+    def test_times_zero_or_negative_floored_to_one(self):
+        a = FakeAsset("a1", metadata={})
+        mark_asset_used_for_generation(a, times=0)
+        assert a.metadata["generation_use_count"] == 1
+
+    def test_preserves_existing_metadata(self):
+        a = FakeAsset("a1", metadata={"tags": ["travel"], "generation_use_count": 4})
+        mark_asset_used_for_generation(a, times=2)
+        assert a.metadata["tags"] == ["travel"]
+        assert a.metadata["generation_use_count"] == 6
+
+
+# ── _count_plan_clip_asset_usage ────────────────────────────────────────────
+
+
+def _mock_session_with_clips(clip_asset_ids: list[str]):
+    """构造 mock session：query(EditPlanClipModel).filter().all() 返回片段 asset_id 行。"""
+    rows = [(aid,) for aid in clip_asset_ids]
+    session = MagicMock()
+    session.query.return_value.filter.return_value.all.return_value = rows
+    return session
+
+
+class TestCountPlanClipUsage:
+    def test_counts_asset_occurrences_across_clips(self):
+        """plan clips 中 asset-x 出现 2 次、asset-y 1 次 → {x:2, y:1}。"""
+        session = _mock_session_with_clips(["asset-x", "asset-y", "asset-x", ""])
+        with _patch_clip_model():
+            counts = gen_mod._count_plan_clip_asset_usage(session, "plan-1")
+        assert counts == {"asset-x": 2, "asset-y": 1}
+
+    def test_empty_clips_returns_empty(self):
+        session = _mock_session_with_clips([])
+        with _patch_clip_model():
+            counts = gen_mod._count_plan_clip_asset_usage(session, "plan-9")
+        assert counts == {}
+
+    def test_blank_asset_ids_skipped(self):
+        session = _mock_session_with_clips(["", None, "asset-z"])
+        with _patch_clip_model():
+            counts = gen_mod._count_plan_clip_asset_usage(session, "plan-1")
+        assert counts == {"asset-z": 1}
+
+
+class _patch_clip_model:
+    """patch generation 模块内 EditPlanClipModel 的导入路径（函数内 import）。"""
+
+    def __enter__(self):
+        import unittest.mock as mock
+
+        self._patches = [
+            mock.patch("packages.adapters.sqlalchemy_impl.models.EditPlanClipModel", MagicMock()),
+        ]
+        for p in self._patches:
+            p.start()
+        return self
+
+    def __exit__(self, *exc):
+        for p in self._patches:
+            p.stop()
+        return False
+
+
+# ── _record_rendered_asset_usage ────────────────────────────────────────────
+
+
+class TestRecordRenderedAssetUsage:
+    def _run(self, clip_ids, fallback_ids=None, repo_get_override=None, repo_update_side=None):
+        session = _mock_session_with_clips(clip_ids)
+        assets: dict[str, FakeAsset] = {}
+
+        def fake_repo_init(sess):
+            repo = MagicMock()
+
+            def fake_get(aid):
+                if repo_get_override and aid in repo_get_override:
+                    return repo_get_override[aid]
+                return assets.setdefault(aid, FakeAsset(aid, metadata={}))
+
+            repo.get.side_effect = fake_get
+            if repo_update_side:
+                repo.update.side_effect = repo_update_side
+            else:
+                repo.update.side_effect = lambda a: a
+            return repo
+
+        import unittest.mock as mock
+
+        with (
+            mock.patch(
+                "packages.adapters.sqlalchemy_impl.asset_repository.SQLAlchemyAssetRepository",
+                side_effect=fake_repo_init,
+            ),
+            _patch_clip_model(),
+        ):
+            written = gen_mod._record_rendered_asset_usage(session, "plan-1", "task-1", fallback_asset_ids=fallback_ids)
+        return written, assets
+
+    def test_writes_by_plan_clips_not_request_asset_ids(self):
+        """核心口径：plan clips 用 x×2 + y×1；请求里的 z（未被 plan 选用）不计数。"""
+        written, assets = self._run(
+            clip_ids=["asset-x", "asset-x", "asset-y"],
+            fallback_ids=["asset-x", "asset-y", "asset-z"],
+        )
+        assert written == 2
+        assert assets["asset-x"].metadata["generation_use_count"] == 2
+        assert assets["asset-y"].metadata["generation_use_count"] == 1
+        assert "asset-z" not in assets, "未被 plan 选用的素材不应被计数"
+
+    def test_fallback_to_task_asset_ids_when_plan_empty(self):
+        """plan 无有效片段（异常数据）→ 兜底任务 asset_ids 每个计 1 次。"""
+        written, assets = self._run(clip_ids=[""], fallback_ids=["asset-a", "asset-b"])
+        assert written == 2
+        assert assets["asset-a"].metadata["generation_use_count"] == 1
+        assert assets["asset-b"].metadata["generation_use_count"] == 1
+
+    def test_no_clips_no_fallback_returns_zero(self):
+        written, assets = self._run(clip_ids=[], fallback_ids=[])
+        assert written == 0
+        assert assets == {}
+
+    def test_single_asset_failure_does_not_block_others(self):
+        """单素材 update 抛异常不影响其他素材回写。"""
+
+        def update_side(a):
+            if a.id == "bad":
+                raise RuntimeError("DB boom")
+            return a
+
+        written, assets = self._run(
+            clip_ids=["good1", "bad", "good2"],
+            fallback_ids=None,
+            repo_update_side=update_side,
+        )
+        assert written == 2
+        assert assets["good1"].metadata["generation_use_count"] == 1
+        assert assets["good2"].metadata["generation_use_count"] == 1
+
+    def test_missing_asset_skipped(self):
+        """repo.get 返回 None 的素材跳过，不报错。"""
+        written, assets = self._run(
+            clip_ids=["ghost", "real"],
+            fallback_ids=None,
+            repo_get_override={"ghost": None},
+        )
+        assert written == 1
+        assert assets["real"].metadata["generation_use_count"] == 1

tests/unit/test_auth_bind_wechat_sync.py

@@ -656,7 +656,7 @@ class TestWechatSyncUseCase:
 
         assert error is None
         assert response.is_new_user is True
-        assert response.nickname == "微信用户"
+        assert response.nickname == "小虾同学"
 
     def test_username_uniqueness_suffix(self):
         """When username already exists, a numeric suffix is added."""

tests/unit/test_batch_dedup_helpers_1743.py

@@ -0,0 +1,244 @@
+"""#1743 dedup_helpers 批次查重 + worker 重选 plan 重试函数测试。
+
+覆盖：
+- 批次任务且无历史重复时走 check_batch_duplicate，batch_similarity 透传到返回 dict
+- 批次任务历史已重复 → 不再做批次查重，is_duplicate=True / duplicate_of 透传
+- 非批次任务 batch_similarity 恒为 None
+- _reselect_plan_for_batch_retry：成功返回新 plan_id；异常返回 None（保留首版）
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+REPO_ROOT = Path(__file__).resolve().parents[2]
+for sub in ("apps/worker", "apps/api", "packages", ""):
+    p = str(REPO_ROOT / sub) if sub else str(REPO_ROOT)
+    if p not in sys.path:
+        sys.path.insert(0, p)
+
+from sqlalchemy import create_engine  # noqa: E402
+from sqlalchemy.orm import sessionmaker  # noqa: E402
+
+os.environ.setdefault("DATABASE_URL", "sqlite:///:memory:")
+from packages.adapters.sqlalchemy_impl.models import Base  # noqa: E402
+
+
+@pytest.fixture
+def session():
+    engine = create_engine("sqlite:///:memory:")
+    Base.metadata.create_all(engine)
+    s = sessionmaker(bind=engine)()
+    try:
+        yield s
+    finally:
+        s.close()
+
+
+def _dedup_kwargs(batch_id):
+    return dict(
+        generation_task_id="task-batch-1",
+        project_id="proj-1",
+        user_id="user-1",
+        batch_id=batch_id,
+        file_url="https://oss.example.com/v.mp4",
+        file_size=1024,
+        duration=10.0,
+        video_path="/tmp/fake.mp4",
+        mode="edit_plan",
+        width=1280,
+        height=720,
+        fps=25.0,
+    )
+
+
+class TestBatchDedupInHelpers:
+    """dedup_helpers 内部 lazy import video_processing.dedup（依赖 cv2），
+    复用 test_generated_video_creation_logic 的 mock 模块注册模式。"""
+
+    @classmethod
+    def setup_class(cls):
+        import sys
+
+        if "cv2" not in sys.modules:
+            sys.modules["cv2"] = MagicMock()
+
+        # 保存 setup 前的真实模块引用，teardown 原样还原（沙箱无 cv2 时 reimport 会失败，
+        # 若直接 pop 掉 MagicMock 会让后续测试（如 test_dedup_1702）拿到残缺模块）
+        import video_processing
+
+        cls._orig_dedup = sys.modules.get("video_processing.dedup")
+        cls._orig_dedup_attr = getattr(video_processing, "dedup", None)
+        cls._orig_thumb = sys.modules.get("video_processing.thumbnail_generator")
+        cls._orig_thumb_attr = getattr(video_processing, "thumbnail_generator", None)
+
+        mock_dedup = MagicMock()
+        mock_dedup.VideoDeduplicator = MagicMock()
+        sys.modules["video_processing.dedup"] = mock_dedup
+
+        mock_thumb = MagicMock()
+        mock_thumb.extract_first_frame = MagicMock()
+        sys.modules["video_processing.thumbnail_generator"] = mock_thumb
+
+        video_processing.dedup = mock_dedup
+        video_processing.thumbnail_generator = mock_thumb
+
+    @classmethod
+    def teardown_class(cls):
+        import sys
+
+        import video_processing
+
+        # 还原 setup 前状态：原本有真模块→放回；原本没有→移除 mock
+        if cls._orig_dedup is not None:
+            sys.modules["video_processing.dedup"] = cls._orig_dedup
+        else:
+            sys.modules.pop("video_processing.dedup", None)
+        if cls._orig_dedup_attr is not None:
+            video_processing.dedup = cls._orig_dedup_attr
+        elif hasattr(video_processing, "dedup"):
+            delattr(video_processing, "dedup")
+
+        if cls._orig_thumb is not None:
+            sys.modules["video_processing.thumbnail_generator"] = cls._orig_thumb
+        else:
+            sys.modules.pop("video_processing.thumbnail_generator", None)
+        if cls._orig_thumb_attr is not None:
+            video_processing.thumbnail_generator = cls._orig_thumb_attr
+        elif hasattr(video_processing, "thumbnail_generator"):
+            delattr(video_processing, "thumbnail_generator")
+
+    def test_batch_similarity_returned_when_batch_duplicate_found(self, session):
+        """批次任务 + 无历史重复 + 批次查重命中 → 返回 batch_similarity 与 is_duplicate。"""
+        from video_processing.dedup_helpers import create_video_record_and_dedup
+
+        with patch("video_processing.dedup.VideoDeduplicator") as mock_cls:
+            dedup = mock_cls.return_value
+            dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
+            dedup.check_duplicate.return_value = None  # 历史无重复
+            dedup.check_batch_duplicate.return_value = {
+                "duplicate_of": "video-existing",
+                "reason": "batch_similar",
+                "similarity": 0.601,
+            }
+            dedup.compute_duplicate_rate.return_value = {
+                "duplicate_rate": 0.0,
+                "visual_similarity": 0.0,
+                "match_count": 0,
+            }
+
+            result = create_video_record_and_dedup(session=session, **_dedup_kwargs("batch-abc"))
+
+        assert result["video_count"] == 1
+        assert result["batch_similarity"] == pytest.approx(0.601)
+        assert result["is_duplicate"] is True
+        assert result["duplicate_of"] == "video-existing"
+        # 批次查重确实被调用（历史查重为 None 才走批次）
+        dedup.check_batch_duplicate.assert_called_once()
+
+    def test_batch_check_skipped_when_historical_duplicate(self, session):
+        """历史查重已命中 → 不再批次查重，batch_similarity 为 None。"""
+        from video_processing.dedup_helpers import create_video_record_and_dedup
+
+        with patch("video_processing.dedup.VideoDeduplicator") as mock_cls:
+            dedup = mock_cls.return_value
+            dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
+            dedup.check_duplicate.return_value = {
+                "duplicate_of": "video-old",
+                "reason": "global",
+                "similarity": 0.85,
+            }
+            dedup.compute_duplicate_rate.return_value = {
+                "duplicate_rate": 85.0,
+                "visual_similarity": 0.85,
+                "match_count": 3,
+            }
+
+            result = create_video_record_and_dedup(session=session, **_dedup_kwargs("batch-abc"))
+
+        assert result["is_duplicate"] is True
+        assert result["duplicate_of"] == "video-old"
+        assert result["batch_similarity"] is None
+        dedup.check_batch_duplicate.assert_not_called()
+
+    def test_non_batch_never_runs_batch_check(self, session):
+        """非批次任务（batch_id 为空）→ 不调用批次查重，batch_similarity None。"""
+        from video_processing.dedup_helpers import create_video_record_and_dedup
+
+        with patch("video_processing.dedup.VideoDeduplicator") as mock_cls:
+            dedup = mock_cls.return_value
+            dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
+            dedup.check_duplicate.return_value = None
+            dedup.check_batch_duplicate.return_value = {"similarity": 0.99}
+            dedup.compute_duplicate_rate.return_value = {
+                "duplicate_rate": 0.0,
+                "visual_similarity": 0.0,
+                "match_count": 0,
+            }
+
+            result = create_video_record_and_dedup(session=session, **_dedup_kwargs(""))
+
+        assert result["video_count"] == 1
+        assert result["batch_similarity"] is None
+        assert result["is_duplicate"] is False
+        dedup.check_batch_duplicate.assert_not_called()
+
+    def test_batch_no_duplicate_returns_none_similarity(self, session):
+        """批次任务但批次查重也未命中 → batch_similarity None（驱动不重渲）。"""
+        from video_processing.dedup_helpers import create_video_record_and_dedup
+
+        with patch("video_processing.dedup.VideoDeduplicator") as mock_cls:
+            dedup = mock_cls.return_value
+            dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
+            dedup.check_duplicate.return_value = None
+            dedup.check_batch_duplicate.return_value = None
+            dedup.compute_duplicate_rate.return_value = {
+                "duplicate_rate": 0.0,
+                "visual_similarity": 0.0,
+                "match_count": 0,
+            }
+
+            result = create_video_record_and_dedup(session=session, **_dedup_kwargs("batch-xyz"))
+
+        assert result["batch_similarity"] is None
+        assert result["is_duplicate"] is False
+
+
+class TestReselectPlanForBatchRetry:
+    def test_success_returns_new_plan_id(self):
+        """重选成功 → 返回新 plan_id。"""
+        from worker_app.tasks.generation import _reselect_plan_for_batch_retry
+
+        fake_svc = MagicMock()
+        fake_svc.reselect_plan_for_variant.return_value = MagicMock(id="new-plan-999")
+        with patch("app.services.edit_plan_service.EditPlanService", return_value=fake_svc):
+            with patch("worker_app.tasks.generation.SessionLocal") as mock_session_local:
+                mock_session_local.return_value = MagicMock()
+                new_id = _reselect_plan_for_batch_retry(
+                    "task-1",
+                    "old-plan",
+                    {"task_asset_ids": ["a1", "a2"], "user_id": "u-1"},
+                )
+        assert new_id == "new-plan-999"
+        fake_svc.reselect_plan_for_variant.assert_called_once()
+        args, kwargs = fake_svc.reselect_plan_for_variant.call_args
+        assert args[0] == "old-plan"
+        assert args[1] == ["a1", "a2"]
+        assert kwargs["created_by_user_id"] == "u-1"
+
+    def test_failure_returns_none_and_keeps_first_version(self):
+        """重选抛异常 → 返回 None（调用方放弃重渲、保留首版），不抛出。"""
+        from worker_app.tasks.generation import _reselect_plan_for_batch_retry
+
+        fake_svc = MagicMock()
+        fake_svc.reselect_plan_for_variant.side_effect = RuntimeError("db down")
+        with patch("app.services.edit_plan_service.EditPlanService", return_value=fake_svc):
+            with patch("worker_app.tasks.generation.SessionLocal") as mock_session_local:
+                mock_session_local.return_value = MagicMock()
+                result = _reselect_plan_for_batch_retry("task-1", "old-plan", {"task_asset_ids": [], "user_id": "u-1"})
+        assert result is None

tests/unit/test_batch_no_plan_guard.py

@@ -1,7 +1,9 @@
-"""AI Review 回归：批量生成 count>1 但 source_edit_plan_id 为空时不应 IndexError。
+"""#1743 批量生成无可用 plan 守卫。
 
-变体 plan 预克隆仅在 source_edit_plan_id 非空时执行；无源 plan 时
-variant_plan_ids 为空，循环中禁止索引访问，各任务走自身随机选片流程。
+新规则（P0 降重）：count>1 批量生成时必须存在源 plan（前端传入或按模板兜底
+解析到最新 plan），为每个变体独立选片；**无任何可用 plan 时直接 4xx 中断、
+不创建任务**，严禁 N 个任务兜底共用同一 plan 产出同源成片。
+N=1 单视频不受影响（无 plan 时走原有单任务流程）。
 """
 
 import sys
@@ -9,6 +11,9 @@ from pathlib import Path
 from types import SimpleNamespace
 from unittest.mock import MagicMock, patch
 
+import pytest
+from fastapi import HTTPException
+
 REPO_ROOT = Path(__file__).resolve().parents[2]
 if str(REPO_ROOT) not in sys.path:
     sys.path.insert(0, str(REPO_ROOT))
@@ -18,78 +23,117 @@ def _make_user():
     return SimpleNamespace(user=SimpleNamespace(id="user-1"))
 
 
-def _make_request(count):
+def _make_request(count, **overrides):
     from app.schemas.generation_task import CreateGenerationTaskRequest
 
-    return CreateGenerationTaskRequest(
+    fields = dict(
         project_id="proj-1",
         asset_library_id="lib-1",
         strategy_id="one_take",
         asset_ids=["a1"],
         count=count,
-        source_edit_plan_id="",  # 关键：无源 plan（空字符串为假值）
+        source_edit_plan_id="",
     )
+    fields.update(overrides)
+    return CreateGenerationTaskRequest(**fields)
 
 
-class TestBatchNoSourcePlanNoIndexError:
-    def test_count3_without_source_plan_creates_three_tasks(self):
-        """count=3 且无 source_edit_plan_id：不克隆、不 IndexError、创建 3 个任务。"""
+def _common_patches(latest_plan=None):
+    """构造通用 patch 上下文（repo/usecase/enqueue 等）。latest_plan 为模板兜底 plan 或 None。"""
+    repo = MagicMock()
+    repo.count_pending_by_user.return_value = 0
+    repo.count_pending_total.return_value = 0
+    repo.create.side_effect = lambda t: t
+    repo.update.side_effect = lambda t: t
+
+    created = []
+
+    def _fake_execute(cmd):
+        task = MagicMock()
+        task.id = f"task-{len(created) + 1}"
+        task.source_edit_plan_id = cmd.source_edit_plan_id
+        task.status = "pending"
+        task.progress = 0.0
+        task.strategy_id = "one_take"
+        task.error_message = ""
+        task.cover_url = ""
+        task.title_config = {}
+        task.created_at = None
+        task.batch_id = "batch-1"
+        created.append(task)
+        return task
+
+    db = MagicMock()
+    # 模板兜底查最新 plan：返回 latest_plan（None 表示查不到）
+    db.query.return_value.filter.return_value.order_by.return_value.first.return_value = latest_plan
+
+    mock_uc = patch("app.api.routes.generation_tasks.CreateGenerationTaskUseCase")
+    other_patches = [
+        patch("app.api.routes.generation_tasks.safe_enqueue_generation_task", return_value=True),
+        patch("app.api.routes.generation_tasks._writeback_edit_plan_config"),
+        patch(
+            "app.api.routes.generation_tasks._resolve_project_and_library",
+            return_value=("proj-1", ""),
+        ),
+    ]
+    return repo, db, created, mock_uc, other_patches, _fake_execute
+
+
+class TestBatchNoSourcePlanGuard:
+    def test_count3_without_any_plan_rejects_4xx_and_creates_nothing(self):
+        """count=3 且无源 plan、模板兜底也查不到 → 400 中断，零任务创建（严禁同源成片）。"""
         from app.api.routes.generation_tasks import create_generation_task
 
-        repo = MagicMock()
-        repo.count_pending_by_user.return_value = 0
-        repo.count_pending_total.return_value = 0
-        repo.create.side_effect = lambda t: t
-        repo.update.side_effect = lambda t: t
+        repo, db, created, mock_uc, other_patches, fake_exec = _common_patches(latest_plan=None)
+        MockUC = mock_uc.start()
+        MockUC.return_value.execute.side_effect = fake_exec
+        for p in other_patches:
+            p.start()
+        all_patches = [mock_uc] + other_patches
+        try:
+            with pytest.raises(HTTPException) as exc_info:
+                create_generation_task(
+                    _make_request(3),
+                    authenticated_user=_make_user(),
+                    generation_task_repository=repo,
+                    project_repository=MagicMock(),
+                    asset_repository=MagicMock(),
+                    asset_library_repository=MagicMock(),
+                    db=db,
+                )
+            assert exc_info.value.status_code == 400
+        finally:
+            for p in reversed(all_patches):
+                p.stop()
+        assert len(created) == 0, "无 plan 批量必须零任务创建"
 
-        created = []
+    def test_count1_without_plan_still_works(self):
+        """N=1 单视频无 plan 不触发批量守卫（向后兼容，不 4xx）。"""
+        from app.api.routes.generation_tasks import create_generation_task
 
-        def _fake_execute(cmd):
-            task = MagicMock()
-            task.id = f"task-{len(created) + 1}"
-            task.source_edit_plan_id = cmd.source_edit_plan_id
-            task.status = "pending"
-            task.progress = 0.0
-            task.strategy_id = "one_take"
-            task.error_message = ""
-            task.cover_url = None
-            task.title_config = {}
-            task.created_at = None
-            task.batch_id = "batch-1"
-            created.append(task)
-            return task
-
-        with patch("app.api.routes.generation_tasks.CreateGenerationTaskUseCase") as MockUC:
-            MockUC.return_value.execute.side_effect = _fake_execute
-            with patch(
-                "app.api.routes.generation_tasks.safe_enqueue_generation_task",
-                return_value=True,
-            ):
-                with patch("app.api.routes.generation_tasks._writeback_edit_plan_config"):
-                    with patch(
-                        "app.api.routes.generation_tasks._resolve_project_and_library",
-                        return_value=("proj-1", ""),
-                    ):
-                        # 核心断言：不得抛 IndexError（变体 plan 索引守卫）。
-                        # 响应序列化字段与本回归无关，ValidationError 可接受，
-                        # 但 IndexError 必须不出现。
-                        try:
-                            create_generation_task(
-                                _make_request(3),
-                                authenticated_user=_make_user(),
-                                generation_task_repository=repo,
-                                project_repository=MagicMock(),
-                                asset_repository=MagicMock(),
-                                asset_library_repository=MagicMock(),
-                                db=MagicMock(),
-                            )
-                        except IndexError as exc:  # pragma: no cover - 不应发生
-                            pytest.fail(f"无源 plan 批量生成触发 IndexError: {exc}")
-                        except Exception:
-                            # 响应序列化等其他异常与本次守卫无关，忽略
-                            pass
-
-        # 3 个任务全部创建（未因 IndexError 中断）
-        assert len(created) == 3
-        # 无源 plan 时所有任务 source_edit_plan_id 均为空
-        assert all(not t.source_edit_plan_id for t in created)
+        repo, db, created, mock_uc, other_patches, fake_exec = _common_patches(latest_plan=None)
+        MockUC = mock_uc.start()
+        MockUC.return_value.execute.side_effect = fake_exec
+        for p in other_patches:
+            p.start()
+        all_patches = [mock_uc] + other_patches
+        try:
+            create_generation_task(
+                _make_request(1),
+                authenticated_user=_make_user(),
+                generation_task_repository=repo,
+                project_repository=MagicMock(),
+                asset_repository=MagicMock(),
+                asset_library_repository=MagicMock(),
+                db=db,
+            )
+        except HTTPException as e:
+            assert e.status_code != 400, f"N=1 不应被批量守卫拦截: {e.detail}"
+        except Exception:
+            # MagicMock 任务对象下游响应序列化可能抛 ValidationError 等，与批量守卫无关；
+            # 任务已在 usecase.execute 中创建，下方断言 created==1 即证明守卫未拦截。
+            pass
+        finally:
+            for p in reversed(all_patches):
+                p.stop()
+        assert len(created) == 1

tests/unit/test_batch_render_rerender_1743.py

@@ -0,0 +1,80 @@
+"""#1743 worker 批量重渲判定 + 封面哈希选帧纯函数测试。
+
+- should_rerender_for_batch_dedup：批次首版查重率 >20% 才重渲（非批次/重渲版/无查重率不重渲）
+- pick_batch_cover_index：task_id md5 稳定哈希分散候选帧（同任务稳定、跨任务分散）
+"""
+
+from __future__ import annotations
+
+import hashlib
+import sys
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[2]
+for sub in ("apps/worker", "apps/api", "packages", ""):
+    p = str(REPO_ROOT / sub) if sub else str(REPO_ROOT)
+    if p not in sys.path:
+        sys.path.insert(0, p)
+
+from worker_app.tasks.generation import (  # noqa: E402
+    BATCH_RENDER_SIMILARITY_LIMIT,
+    pick_batch_cover_index,
+    should_rerender_for_batch_dedup,
+)
+
+
+class TestShouldRerenderForBatchDedup:
+    def test_non_batch_never_rerenders(self):
+        """非批次任务（batch_id 为空）任何查重率都不重渲。"""
+        assert should_rerender_for_batch_dedup(batch_id="", render_attempt=0, batch_similarity=0.99) is False
+        assert should_rerender_for_batch_dedup(batch_id="", render_attempt=0, batch_similarity=None) is False
+
+    def test_batch_first_version_over_threshold_rerenders(self):
+        """批次首版（attempt=0）查重率 >20% → 重渲。"""
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=0.601) is True
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=0.21) is True
+
+    def test_batch_first_version_under_threshold_no_rerender(self):
+        """批次首版查重率 ≤20% → 不重渲。"""
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=0.20) is False
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=0.0) is False
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=0.05) is False
+
+    def test_rerendered_version_never_rerenders_again(self):
+        """重渲版（attempt=1）即使仍超阈值也不再重渲（最多重渲一次）。"""
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=1, batch_similarity=0.99) is False
+
+    def test_missing_similarity_no_rerender(self):
+        """查重率缺失（None，非批次查重路径）→ 不重渲。"""
+        assert should_rerender_for_batch_dedup(batch_id="batch-1", render_attempt=0, batch_similarity=None) is False
+
+    def test_threshold_constant_is_20_percent(self):
+        assert BATCH_RENDER_SIMILARITY_LIMIT == 0.20
+
+
+class TestPickBatchCoverIndex:
+    def test_stable_for_same_task(self):
+        """同一 task_id 多次调用结果稳定（重试封面不变）。"""
+        first = pick_batch_cover_index("task-abc", 3)
+        for _ in range(5):
+            assert pick_batch_cover_index("task-abc", 3) == first
+
+    def test_zero_or_one_candidate_returns_zero(self):
+        assert pick_batch_cover_index("task-x", 0) == 0
+        assert pick_batch_cover_index("task-x", 1) == 0
+
+    def test_index_within_range(self):
+        for i in range(20):
+            idx = pick_batch_cover_index(f"task-{i}", 3)
+            assert 0 <= idx < 3
+
+    def test_matches_md5_formula(self):
+        """与主流程公式一致：md5(task_id) % 候选数。"""
+        task_id = "task-formula-check"
+        expected = int(hashlib.md5(task_id.encode()).hexdigest(), 16) % 3
+        assert pick_batch_cover_index(task_id, 3) == expected
+
+    def test_batch_tasks_spread_across_frames(self):
+        """30 个批次任务在 3 个候选帧上分散（不能全部落在 frame_0——旧 bug 回归守卫）。"""
+        indexes = {pick_batch_cover_index(f"batch-task-{i}", 3) for i in range(30)}
+        assert len(indexes) >= 2, f"封面帧应分散到多个帧位，实际全部落在: {indexes}"

tests/unit/test_confirm_generation.py

@@ -356,7 +356,8 @@ class TestConfirmGenerationErrors:
         assert item["voice_library_id"] == "voice-001"
         assert item["template_id"] == "tmpl-001"
         assert item["title_ids"] == ["title-1", "title-2"]
-        assert item["voice_ids"] == ["voice-a"]
+        # #1749：voice_ids 已废弃（配音走 voice_library_id），确认生成不再保留原值
+        assert item["voice_ids"] == []
 
     def test_confirm_cover_and_title(
         self,

tests/unit/test_cover_frame_scorer.py

@@ -0,0 +1,226 @@
+"""封面帧质量评分器测试 — cover_frame_scorer.
+
+测试维度：
+1. score_frame: 清晰度/亮度/色彩丰富度各维度评分
+2. score_frames: 批量评分和排序
+3. select_best_frame: 选出最佳帧
+4. 降级策略：cv2 不可用时返回默认分
+5. 边界条件：空帧、None、损坏数据
+"""
+
+from __future__ import annotations
+
+import inspect
+
+import numpy as np
+import pytest
+
+
+def _cv2_available() -> bool:
+    """检测 cv2 是否真实可用（非 mock）."""
+    try:
+        import cv2
+        import numpy as np
+
+        if not hasattr(cv2, "Laplacian") or not inspect.isroutine(cv2.Laplacian):
+            return False
+        if "mock" in str(type(cv2.Laplacian)).lower():
+            return False
+        # 实际调用测试
+        _test = np.zeros((2, 2, 3), dtype=np.uint8)
+        _result = cv2.cvtColor(_test, cv2.COLOR_BGR2GRAY)
+        return isinstance(_result, np.ndarray)
+    except Exception:
+        return False
+
+
+HAS_CV2 = _cv2_available()
+requires_cv2 = pytest.mark.skipif(not HAS_CV2, reason="cv2 不可用或是 mock 对象")
+
+
+class TestScoreFrame:
+    """score_frame 单元测试."""
+
+    @requires_cv2
+    def test_clear_image_high_score(self):
+        """清晰、亮度适中、色彩丰富的图像应得高分."""
+        # 创建一个清晰的渐变图像（色彩丰富、亮度适中）
+        img = np.zeros((100, 100, 3), dtype=np.uint8)
+        for i in range(100):
+            for j in range(100):
+                img[i, j] = [i * 2, j * 2, (i + j) % 256]
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        assert 50.0 <= score <= 100.0, f"清晰图像应得高分，实际: {score}"
+
+    @requires_cv2
+    def test_blurry_image_low_clarity(self):
+        """模糊图像的清晰度分数应较低."""
+        # 纯色图像（无高频细节）
+        img = np.full((100, 100, 3), 128, dtype=np.uint8)
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        # 纯色图像清晰度为 0，亮度满分 30，色彩为 0
+        assert score <= 35.0, f"模糊图像应低分，实际: {score}"
+
+    @requires_cv2
+    def test_dark_image_low_brightness(self):
+        """过暗图像应扣分."""
+        # 全黑图像
+        img = np.zeros((100, 100, 3), dtype=np.uint8)
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        # 全黑：清晰度 0，亮度 0，色彩 0
+        assert score <= 5.0, f"全黑图像应接近 0 分，实际: {score}"
+
+    @requires_cv2
+    def test_bright_image_low_brightness(self):
+        """过亮图像应扣分."""
+        # 全白图像
+        img = np.full((100, 100, 3), 255, dtype=np.uint8)
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        # 全白：清晰度 0（无边缘），亮度偏低（偏离 130），色彩 0
+        assert score <= 20.0, f"全白图像应较低分，实际: {score}"
+
+    @requires_cv2
+    def test_medium_brightness_full_score(self):
+        """亮度在 80~180 区间应得亮度满分."""
+        # 中等亮度灰色
+        img = np.full((100, 100, 3), 130, dtype=np.uint8)
+        # 加一些纹理增加清晰度
+        for i in range(0, 100, 10):
+            img[i : i + 5, :] = 180
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        # 亮度应在舒适区间
+        assert score >= 25.0, f"中等亮度图像应有一定分数，实际: {score}"
+
+    @requires_cv2
+    def test_colorful_image_high_color_score(self):
+        """色彩丰富的图像应得高色彩分."""
+        # 彩虹渐变
+        img = np.zeros((100, 100, 3), dtype=np.uint8)
+        for i in range(100):
+            img[i, :, 0] = int(i * 2.55)  # R
+            img[i, :, 1] = int((100 - i) * 2.55)  # G
+            img[:, i, 2] = int(i * 2.55)  # B
+
+        from packages.shared.cover_frame_scorer import score_frame
+
+        score = score_frame(img)
+        assert score >= 40.0, f"彩色图像应得高分，实际: {score}"
+
+    @requires_cv2
+    def test_empty_frame_returns_zero(self):
+        """空帧返回 0 分（有 cv2）或默认分（无 cv2）."""
+        from packages.shared.cover_frame_scorer import score_frame
+
+        result1 = score_frame(np.array([]))
+        result2 = score_frame(None)
+        if HAS_CV2:
+            assert result1 == 0.0
+            assert result2 == 0.0
+        else:
+            assert result1 == 50.0
+            assert result2 == 50.0
+
+    @requires_cv2
+    def test_score_range(self):
+        """评分必须在 0~100 范围内."""
+        from packages.shared.cover_frame_scorer import score_frame
+
+        # 各种极端情况
+        for val in [0, 50, 128, 200, 255]:
+            img = np.full((50, 50, 3), val, dtype=np.uint8)
+            score = score_frame(img)
+            assert 0.0 <= score <= 100.0, f"评分 {score} 超出范围 [0, 100]"
+
+
+class TestScoreFrames:
+    """score_frames 批量评分测试."""
+
+    @requires_cv2
+    def test_returns_sorted_by_score(self):
+        """返回结果应按分数从高到低排序."""
+        from packages.shared.cover_frame_scorer import score_frames
+
+        frames = [
+            {"image_array": np.full((50, 50, 3), 128, dtype=np.uint8), "id": "mid"},
+            {"image_array": np.zeros((50, 50, 3), dtype=np.uint8), "id": "dark"},
+        ]
+        # 添加一个清晰帧
+        clear = np.zeros((50, 50, 3), dtype=np.uint8)
+        for i in range(50):
+            clear[i, :, :] = i * 5
+        frames.insert(0, {"image_array": clear, "id": "clear"})
+
+        scored = score_frames(frames)
+        assert len(scored) == 3
+        # 第一个应该是分数最高的
+        assert scored[0]["score"] >= scored[1]["score"]
+        assert scored[1]["score"] >= scored[2]["score"]
+
+    @requires_cv2
+    def test_all_have_score_field(self):
+        """每个帧都应该有 score 字段."""
+        from packages.shared.cover_frame_scorer import score_frames
+
+        frames = [
+            {"image_array": np.full((30, 30, 3), 100, dtype=np.uint8)},
+            {"image_array": np.full((30, 30, 3), 200, dtype=np.uint8)},
+        ]
+        scored = score_frames(frames)
+        for f in scored:
+            assert "score" in f
+            assert isinstance(f["score"], float)
+
+    def test_empty_list(self):
+        """空列表返回空列表."""
+        from packages.shared.cover_frame_scorer import score_frames
+
+        assert score_frames([]) == []
+
+
+class TestSelectBestFrame:
+    """select_best_frame 测试."""
+
+    @requires_cv2
+    def test_returns_highest_score(self):
+        """返回分数最高的帧."""
+        from packages.shared.cover_frame_scorer import select_best_frame
+
+        frames = [
+            {"image_array": np.zeros((30, 30, 3), dtype=np.uint8), "id": "dark"},
+            {"image_array": np.full((30, 30, 3), 128, dtype=np.uint8), "id": "mid"},
+        ]
+        best = select_best_frame(frames)
+        assert best is not None
+        # 中等亮度帧应该得分更高
+        assert best["id"] == "mid"
+
+    def test_empty_returns_none(self):
+        """空列表返回 None."""
+        from packages.shared.cover_frame_scorer import select_best_frame
+
+        assert select_best_frame([]) is None
+
+    @requires_cv2
+    def test_single_frame(self):
+        """单帧直接返回."""
+        from packages.shared.cover_frame_scorer import select_best_frame
+
+        frames = [{"image_array": np.full((30, 30, 3), 128, dtype=np.uint8), "id": "only"}]
+        best = select_best_frame(frames)
+        assert best is not None
+        assert best["id"] == "only"

tests/unit/test_dedup_enhanced.py

@@ -0,0 +1,207 @@
+"""Tests for enhanced dedup: text + structure dimensions (Issue #P2-后端3)."""
+
+from __future__ import annotations
+
+import sys
+from unittest.mock import MagicMock
+
+# ---------------------------------------------------------------------------
+# Mock heavy deps before importing dedup module
+# ---------------------------------------------------------------------------
+_ORIGINAL_MODULES = dict(sys.modules)
+_MOCKED_MODULE_NAMES: list[str] = []
+
+
+def _mock_if_absent(name: str, mock_obj=None):
+    """仅在模块不在 sys.modules 中时注入 mock，并记录以便清理。"""
+    if name not in sys.modules:
+        sys.modules[name] = mock_obj if mock_obj is not None else MagicMock()
+        _MOCKED_MODULE_NAMES.append(name)
+
+
+# Mock heavy deps
+_mock_if_absent("ffmpeg")
+_mock_if_absent("ffmpeg.utils")
+_mock_if_absent("worker_app.celery_app")
+_mock_if_absent("worker_app.db")
+_mock_if_absent("packages.adapters.sqlalchemy_impl.generated_video_repository")
+_mock_if_absent("packages.adapters.sqlalchemy_impl.models")
+_mock_if_absent("packages.shared.storage")
+
+# Mock cv2 and numpy if not available
+try:
+    import cv2 as _cv2
+
+    if not isinstance(_cv2, MagicMock):
+        _HAS_CV2 = True
+    else:
+        _HAS_CV2 = False
+except ImportError:
+    _HAS_CV2 = False
+    _mock_if_absent("cv2")
+    _mock_if_absent("numpy")
+
+import pytest
+
+from apps.worker.video_processing.dedup import (
+    STRUCTURE_WEIGHT,
+    TEXT_WEIGHT,
+    VISUAL_WEIGHT,
+    compute_structure_similarity,
+    compute_text_similarity,
+)
+
+
+class TestTextSimilarity:
+    """Tests for compute_text_similarity."""
+
+    def test_identical_texts(self):
+        """相同文本返回 1.0。"""
+        assert compute_text_similarity("你好世界", "你好世界") == 1.0
+
+    def test_empty_texts(self):
+        """都为空返回 1.0。"""
+        assert compute_text_similarity("", "") == 1.0
+
+    def test_one_empty(self):
+        """一个为空返回 0.0。"""
+        assert compute_text_similarity("你好", "") == 0.0
+        assert compute_text_similarity("", "你好") == 0.0
+
+    def test_completely_different(self):
+        """完全不同文本返回低相似度。"""
+        sim = compute_text_similarity("你好世界", "abcdefgh")
+        assert sim < 0.3
+
+    def test_partial_overlap(self):
+        """部分重叠文本返回中等相似度。"""
+        sim = compute_text_similarity("今天天气真好", "今天天气不错")
+        assert 0.3 < sim < 0.9
+
+    def test_case_insensitive(self):
+        """英文大小写不敏感。"""
+        sim = compute_text_similarity("Hello World", "hello world")
+        assert sim == 1.0
+
+    def test_whitespace_ignored(self):
+        """空白字符被忽略。"""
+        sim = compute_text_similarity("你好 世界", "你好世界")
+        assert sim == 1.0
+
+    def test_punctuation_ignored(self):
+        """标点符号被忽略。"""
+        sim = compute_text_similarity("你好，世界！", "你好世界")
+        assert sim == 1.0
+
+    def test_long_texts(self):
+        """长文本也能计算。"""
+        t1 = "这是一段很长的配音文本，用于测试文案查重功能"
+        t2 = "这是一段较长的配音文字，用于测试文案去重功能"
+        sim = compute_text_similarity(t1, t2)
+        assert 0.0 <= sim <= 1.0
+
+
+class TestStructureSimilarity:
+    """Tests for compute_structure_similarity."""
+
+    def test_identical_structures(self):
+        """完全相同结构返回 1.0。"""
+        clips = [
+            {"clip_type": "video", "duration": 5.0},
+            {"clip_type": "title", "duration": 2.0},
+            {"clip_type": "video", "duration": 8.0},
+        ]
+        assert compute_structure_similarity(clips, clips) == 1.0
+
+    def test_empty_clips(self):
+        """都为空返回 1.0。"""
+        assert compute_structure_similarity([], []) == 1.0
+
+    def test_one_empty(self):
+        """一个为空返回 0.0。"""
+        clips = [{"clip_type": "video", "duration": 5.0}]
+        assert compute_structure_similarity(clips, []) == 0.0
+        assert compute_structure_similarity([], clips) == 0.0
+
+    def test_different_count(self):
+        """片段数不同，相似度降低。"""
+        clips1 = [
+            {"clip_type": "video", "duration": 5.0},
+            {"clip_type": "title", "duration": 2.0},
+        ]
+        clips2 = [
+            {"clip_type": "video", "duration": 5.0},
+            {"clip_type": "title", "duration": 2.0},
+            {"clip_type": "video", "duration": 3.0},
+            {"clip_type": "title", "duration": 1.0},
+        ]
+        sim = compute_structure_similarity(clips1, clips2)
+        assert 0.0 < sim < 0.8
+
+    def test_different_types(self):
+        """片段类型不同，类型相似度低。"""
+        clips1 = [
+            {"clip_type": "video", "duration": 5.0},
+            {"clip_type": "video", "duration": 3.0},
+        ]
+        clips2 = [
+            {"clip_type": "title", "duration": 5.0},
+            {"clip_type": "title", "duration": 3.0},
+        ]
+        sim = compute_structure_similarity(clips1, clips2)
+        assert sim <= 0.6  # 类型全部不同，但数量和时长相同贡献 0.6
+
+    def test_different_duration_distribution(self):
+        """时长分布不同，时长相似度低。"""
+        clips1 = [
+            {"clip_type": "video", "duration": 10.0},  # 占比 80%
+            {"clip_type": "title", "duration": 2.5},  # 占比 20%
+        ]
+        clips2 = [
+            {"clip_type": "video", "duration": 2.0},  # 占比 20%
+            {"clip_type": "title", "duration": 8.0},  # 占比 80%
+        ]
+        sim = compute_structure_similarity(clips1, clips2)
+        assert 0.7 < sim < 0.9  # 类型相同但时长分布不同，sim=0.82
+
+    def test_similar_structure(self):
+        """相似结构返回较高相似度。"""
+        clips1 = [
+            {"clip_type": "video", "duration": 5.0},
+            {"clip_type": "title", "duration": 2.0},
+            {"clip_type": "video", "duration": 8.0},
+        ]
+        clips2 = [
+            {"clip_type": "video", "duration": 5.5},
+            {"clip_type": "title", "duration": 2.2},
+            {"clip_type": "video", "duration": 7.5},
+        ]
+        sim = compute_structure_similarity(clips1, clips2)
+        assert sim > 0.8
+
+    def test_single_clip(self):
+        """单片段也能计算。"""
+        clips1 = [{"clip_type": "video", "duration": 10.0}]
+        clips2 = [{"clip_type": "video", "duration": 12.0}]
+        sim = compute_structure_similarity(clips1, clips2)
+        assert sim > 0.5  # 类型相同，数量相同，只是时长不同
+
+
+class TestDimensionWeights:
+    """Tests for dimension weight constants."""
+
+    def test_weights_sum_to_one(self):
+        """多维度权重之和为 1.0。"""
+        assert abs(VISUAL_WEIGHT + TEXT_WEIGHT + STRUCTURE_WEIGHT - 1.0) < 1e-9
+
+    def test_visual_weight_is_half(self):
+        """视觉权重为 0.5。"""
+        assert VISUAL_WEIGHT == 0.5
+
+    def test_text_weight_is_quarter(self):
+        """文案权重为 0.25。"""
+        assert TEXT_WEIGHT == 0.25
+
+    def test_structure_weight_is_quarter(self):
+        """结构权重为 0.25。"""
+        assert STRUCTURE_WEIGHT == 0.25

tests/unit/test_dedup_two_phase_commit.py

@@ -85,7 +85,10 @@ class TestTwoPhaseCommit:
                 session=session,
             )
 
-        assert result == 1
+        # #1743：返回值由 int 改为 dict（含批次查重信息）
+        assert isinstance(result, dict)
+        assert result["video_count"] == 1
+        assert result["batch_similarity"] is None  # 非批次任务无批次相似度
         # create() should be called exactly once with the complete video object
         mock_repo.create.assert_called_once()
         created_video = mock_repo.create.call_args[0][0]
@@ -122,7 +125,10 @@ class TestTwoPhaseCommit:
                 session=session,
             )
 
-        assert result == 1
+        # #1743：返回值由 int 改为 dict（含批次查重信息）
+        assert isinstance(result, dict)
+        assert result["video_count"] == 1
+        assert result["batch_similarity"] is None  # 非批次任务无批次相似度
         mock_repo.create.assert_called_once()
         created_video = mock_repo.create.call_args[0][0]
         assert created_video.duplicate_rate is None
@@ -161,7 +167,10 @@ class TestTwoPhaseCommit:
                 session=session,
             )
 
-        assert result == 1
+        # #1743：返回值由 int 改为 dict（含批次查重信息）
+        assert isinstance(result, dict)
+        assert result["video_count"] == 1
+        assert result["batch_similarity"] is None  # 非批次任务无批次相似度
         mock_repo.create.assert_called_once()
         created_video = mock_repo.create.call_args[0][0]
         # Fingerprint should be set
@@ -229,6 +238,7 @@ class TestTwoPhaseCommit:
                 session=session,
             )
 
-        assert result == 0
+        # #1743：失败路径返回 dict（video_count=0）
+        assert result["video_count"] == 0
         session.commit.assert_not_called()
         session.rollback.assert_called_once()

tests/unit/test_duration_compensation.py

@@ -10,8 +10,11 @@ from apps.worker.video_processing.unified_render_service import ResolvedClip, Un
 class TestClipEffectiveDurationWithSpeedCompensation:
     """Test _clip_effective_duration handles speed < 1 correctly."""
 
-    def test_normal_speed_returns_min(self):
-        """When speed=1.0, effective_duration = min(duration, actual_duration)."""
+    def test_normal_speed_returns_target_duration(self):
+        """#1749：speed=1.0 时 effective_duration 始终为目标段长 duration。
+
+        素材短于段长不再慢放补偿，差值由末帧冻结 tpad / 音频 apad 铺满。
+        """
         clip = ResolvedClip(
             clip_id="c1",
             asset_id="a1",
@@ -23,11 +26,10 @@ class TestClipEffectiveDurationWithSpeedCompensation:
             actual_duration=3.0,  # shorter than configured
             playback_speed=1.0,
         )
-        # Without speed compensation, effective = min(4, 3) = 3
-        assert UnifiedRenderService._clip_effective_duration(clip) == 3.0
+        assert UnifiedRenderService._clip_effective_duration(clip) == 4.0
 
-    def test_compensated_speed_returns_configured_duration(self):
-        """When speed < 1 (compensated), effective_duration = configured duration."""
+    def test_explicit_speed_does_not_change_effective_duration(self):
+        """#1749：effective_duration 只认目标段长，与 playback_speed 无关（慢放补偿已删除）。"""
         clip = ResolvedClip(
             clip_id="c1",
             asset_id="a1",
@@ -37,9 +39,8 @@ class TestClipEffectiveDurationWithSpeedCompensation:
             start_time=0.0,
             duration=4.0,
             actual_duration=3.0,  # shorter than configured
-            playback_speed=0.75,  # compensated: 3/4 = 0.75
+            playback_speed=0.75,
         )
-        # With speed compensation, effective = configured duration = 4.0
         assert UnifiedRenderService._clip_effective_duration(clip) == 4.0
 
     def test_zero_actual_duration_returns_configured(self):
@@ -76,10 +77,10 @@ class TestClipEffectiveDurationWithSpeedCompensation:
 class TestClipAdjustedDurationWithSpeedCompensation:
     """Test _clip_adjusted_duration accounts for compensated speed."""
 
-    def test_adjusted_duration_with_compensation(self):
-        """Adjusted duration = min(duration, actual) / speed.
-        With compensation: min(4,3)/0.75 = 3/0.75 = 4.0
-        This equals the configured duration, which is the goal.
+    def test_adjusted_duration_with_explicit_speed(self):
+        """#1749：adjusted duration = 目标段长 / speed（用户显式调速仍生效；短素材不再自动慢放）。
+
+        4.0 / 0.75 ≈ 5.333。
         """
         clip = ResolvedClip(
             clip_id="c1",
@@ -90,8 +91,8 @@ class TestClipAdjustedDurationWithSpeedCompensation:
             start_time=0.0,
             duration=4.0,
             actual_duration=3.0,
-            playback_speed=0.75,  # compensated
+            playback_speed=0.75,
         )
         adjusted = UnifiedRenderService._clip_adjusted_duration(clip)
-        # min(4,3)/0.75 = 3/0.75 = 4.0 (matches configured duration)
-        assert abs(adjusted - 4.0) < 0.01
+        # 4.0 / 0.75 = 5.333...
+        assert abs(adjusted - (4.0 / 0.75)) < 0.01

tests/unit/test_ffmpeg_encoding_optimization.py

@@ -0,0 +1,348 @@
+"""Tests for FFmpeg encoding optimization (#1758).
+
+验证：
+1. 集中编码常量正确定义，支持环境变量覆盖
+2. 所有渲染路径（_execute_ffmpeg / _render_pass_through / normalize_video / processor）
+   使用统一的编码参数
+3. preset 从 medium → fast，确保渲染速度提升
+4. threads=0 自动检测 CPU 核心数
+"""
+
+from __future__ import annotations
+
+import importlib
+import os
+import sys
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+# ── 常量定义与默认值 ─────────────────────────────────────────────────────────
+
+
+class TestEncodingConstants:
+    """测试集中编码常量的定义与默认值."""
+
+    def test_default_preset_is_fast(self):
+        """默认 preset 应为 fast（非 medium），确保速度提升."""
+        from shared.ffmpeg_utils import FFMPEG_ENCODE_PRESET
+
+        assert FFMPEG_ENCODE_PRESET == "fast"
+
+    def test_default_crf_is_23(self):
+        """默认 CRF 保持 23，画质不变."""
+        from shared.ffmpeg_utils import FFMPEG_ENCODE_CRF
+
+        assert FFMPEG_ENCODE_CRF == "23"
+
+    def test_default_threads_is_auto(self):
+        """默认线程数为 0（自动检测 CPU 核心数）."""
+        from shared.ffmpeg_utils import FFMPEG_ENCODE_THREADS
+
+        assert FFMPEG_ENCODE_THREADS == "0"
+
+    def test_preset_is_not_medium(self):
+        """确保 preset 不再是 medium（验证改动生效）."""
+        from shared.ffmpeg_utils import FFMPEG_ENCODE_PRESET
+
+        assert FFMPEG_ENCODE_PRESET != "medium"
+
+
+# ── 环境变量覆盖 ─────────────────────────────────────────────────────────────
+
+
+class TestEnvironmentVariableOverride:
+    """测试环境变量覆盖编码参数."""
+
+    def _reload_module(self):
+        """重新加载模块以读取环境变量."""
+        import shared.ffmpeg_utils
+
+        return importlib.reload(shared.ffmpeg_utils)
+
+    def test_override_preset_via_env(self, monkeypatch):
+        """通过环境变量覆盖 preset."""
+        monkeypatch.setenv("FFMPEG_ENCODE_PRESET", "ultrafast")
+        mod = self._reload_module()
+        assert mod.FFMPEG_ENCODE_PRESET == "ultrafast"
+        # 恢复
+        monkeypatch.delenv("FFMPEG_ENCODE_PRESET", raising=False)
+        self._reload_module()
+
+    def test_override_crf_via_env(self, monkeypatch):
+        """通过环境变量覆盖 CRF."""
+        monkeypatch.setenv("FFMPEG_ENCODE_CRF", "18")
+        mod = self._reload_module()
+        assert mod.FFMPEG_ENCODE_CRF == "18"
+        monkeypatch.delenv("FFMPEG_ENCODE_CRF", raising=False)
+        self._reload_module()
+
+    def test_override_threads_via_env(self, monkeypatch):
+        """通过环境变量覆盖线程数."""
+        monkeypatch.setenv("FFMPEG_ENCODE_THREADS", "4")
+        mod = self._reload_module()
+        assert mod.FFMPEG_ENCODE_THREADS == "4"
+        monkeypatch.delenv("FFMPEG_ENCODE_THREADS", raising=False)
+        self._reload_module()
+
+
+# ── Worker 层 re-export ──────────────────────────────────────────────────────
+
+
+class TestWorkerReExport:
+    """测试 worker 层 ffmpeg_utils 正确 re-export 编码常量."""
+
+    def test_worker_reexports_preset(self):
+        """worker ffmpeg_utils 应 re-export FFMPEG_ENCODE_PRESET."""
+        from video_processing.ffmpeg_utils import FFMPEG_ENCODE_PRESET
+
+        assert FFMPEG_ENCODE_PRESET == "fast"
+
+    def test_worker_reexports_crf(self):
+        """worker ffmpeg_utils 应 re-export FFMPEG_ENCODE_CRF."""
+        from video_processing.ffmpeg_utils import FFMPEG_ENCODE_CRF
+
+        assert FFMPEG_ENCODE_CRF == "23"
+
+    def test_worker_reexports_threads(self):
+        """worker ffmpeg_utils 应 re-export FFMPEG_ENCODE_THREADS."""
+        from video_processing.ffmpeg_utils import FFMPEG_ENCODE_THREADS
+
+        assert FFMPEG_ENCODE_THREADS == "0"
+
+
+# ── _execute_ffmpeg 编码参数 ─────────────────────────────────────────────────
+
+
+class TestExecuteFfmpegEncoding:
+    """测试 _execute_ffmpeg 方法使用正确的编码参数."""
+
+    def _get_execute_command(self):
+        """提取 _execute_ffmpeg 构建的 FFmpeg 命令."""
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        service = UnifiedRenderService.__new__(UnifiedRenderService)
+        service.plan = MagicMock()
+        service.plan.id = "test-plan"
+
+        captured_cmd = []
+
+        def mock_run_ffmpeg(cmd, **kwargs):
+            captured_cmd.extend(cmd)
+
+        with patch(
+            "video_processing.unified_render_service.run_ffmpeg",
+            side_effect=mock_run_ffmpeg,
+        ):
+            service._execute_ffmpeg(
+                "test_filter_complex",
+                ["-i", "input.mp4"],
+                __import__("pathlib").Path("/tmp/output.mp4"),
+            )
+
+        return captured_cmd
+
+    def test_execute_uses_fast_preset(self):
+        """_execute_ffmpeg 应使用 fast preset."""
+        cmd = self._get_execute_command()
+        idx = cmd.index("-preset")
+        assert cmd[idx + 1] == "fast"
+
+    def test_execute_uses_crf_23(self):
+        """_execute_ffmpeg 应使用 CRF 23."""
+        cmd = self._get_execute_command()
+        idx = cmd.index("-crf")
+        assert cmd[idx + 1] == "23"
+
+    def test_execute_uses_auto_threads(self):
+        """_execute_ffmpeg 应启用多线程."""
+        cmd = self._get_execute_command()
+        idx = cmd.index("-threads")
+        assert cmd[idx + 1] == "0"
+
+    def test_execute_no_medium_preset(self):
+        """_execute_ffmpeg 不应再使用 medium preset."""
+        cmd = self._get_execute_command()
+        assert "medium" not in cmd
+
+
+# ── _render_pass_through 编码参数 ────────────────────────────────────────────
+
+
+class TestRenderPassThroughEncoding:
+    """测试 _render_pass_through 方法使用正确的编码参数."""
+
+    def test_passthrough_command_contains_fast_preset(self):
+        """_render_pass_through 命令应包含 fast preset."""
+        # 通过源码检查确认参数已替换
+        import inspect
+
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        source = inspect.getsource(UnifiedRenderService._render_pass_through)
+        assert "FFMPEG_ENCODE_PRESET" in source
+        assert "FFMPEG_ENCODE_THREADS" in source
+        assert '"medium"' not in source
+
+    def test_passthrough_command_contains_threads(self):
+        """_render_pass_through 命令应包含 threads 参数."""
+        import inspect
+
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        source = inspect.getsource(UnifiedRenderService._render_pass_through)
+        assert "FFMPEG_ENCODE_THREADS" in source
+
+
+# ── normalize_video 编码参数 ─────────────────────────────────────────────────
+
+
+class TestNormalizeVideoEncoding:
+    """测试 normalize_video 使用正确的编码参数."""
+
+    def test_normalize_uses_fast_preset(self):
+        """normalize_video 应使用 fast preset."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video
+
+        source = inspect.getsource(normalize_video)
+        assert "FFMPEG_ENCODE_PRESET" in source
+        assert '"medium"' not in source
+
+    def test_normalize_uses_configurable_crf(self):
+        """normalize_video CRF 应使用可配置常量."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video
+
+        source = inspect.getsource(normalize_video)
+        assert "FFMPEG_ENCODE_CRF" in source
+
+    def test_normalize_uses_threads(self):
+        """normalize_video 应启用多线程."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video
+
+        source = inspect.getsource(normalize_video)
+        assert "FFMPEG_ENCODE_THREADS" in source
+
+
+# ── random_edge_crop 编码参数 ────────────────────────────────────────────────
+
+
+class TestRandomEdgeCropEncoding:
+    """测试 random_edge_crop 函数使用统一编码参数."""
+
+    def test_crop_uses_unified_preset(self):
+        """random_edge_crop 应使用统一 preset 常量（非硬编码 fast）."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import random_edge_crop
+
+        source = inspect.getsource(random_edge_crop)
+        assert "FFMPEG_ENCODE_PRESET" in source
+
+    def test_crop_uses_unified_crf(self):
+        """random_edge_crop 应使用统一 CRF 常量（非硬编码 18）."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import random_edge_crop
+
+        source = inspect.getsource(random_edge_crop)
+        assert "FFMPEG_ENCODE_CRF" in source
+        assert '"18"' not in source
+
+
+# ── processor.py 编码参数 ────────────────────────────────────────────────────
+
+
+class TestProcessorEncoding:
+    """测试 VideoProcessor 使用统一编码参数."""
+
+    def test_processor_uses_unified_preset(self):
+        """VideoProcessor.concatenate_videos 应使用统一 preset."""
+        import inspect
+
+        from video_processing.processor import VideoProcessor
+
+        source = inspect.getsource(VideoProcessor.concatenate_videos)
+        assert "FFMPEG_ENCODE_PRESET" in source
+        assert 'preset="medium"' not in source
+
+    def test_processor_uses_unified_crf(self):
+        """VideoProcessor.concatenate_videos 应使用统一 CRF."""
+        import inspect
+
+        from video_processing.processor import VideoProcessor
+
+        source = inspect.getsource(VideoProcessor.concatenate_videos)
+        assert "FFMPEG_ENCODE_CRF" in source
+        assert "crf=23" not in source
+
+
+# ── 编码参数一致性验证 ────────────────────────────────────────────────────────
+
+
+class TestEncodingConsistency:
+    """验证所有渲染路径使用同一套编码参数."""
+
+    def test_all_paths_share_same_preset_source(self):
+        """所有路径的 preset 均来自 FFMPEG_ENCODE_PRESET."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video, random_edge_crop
+        from video_processing.processor import VideoProcessor
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        sources = [
+            inspect.getsource(UnifiedRenderService._execute_ffmpeg),
+            inspect.getsource(UnifiedRenderService._render_pass_through),
+            inspect.getsource(normalize_video),
+            inspect.getsource(random_edge_crop),
+            inspect.getsource(VideoProcessor.concatenate_videos),
+        ]
+
+        for i, src in enumerate(sources):
+            assert "FFMPEG_ENCODE_PRESET" in src, f"渲染路径 #{i} 未使用 FFMPEG_ENCODE_PRESET"
+
+    def test_no_hardcoded_medium_preset_anywhere(self):
+        """所有渲染代码中不应再有硬编码的 medium preset."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        for fn in [
+            UnifiedRenderService._execute_ffmpeg,
+            UnifiedRenderService._render_pass_through,
+            normalize_video,
+        ]:
+            src = inspect.getsource(fn)
+            assert '"medium"' not in src, f"{fn.__name__} 仍有硬编码 medium preset"
+
+    def test_no_hardcoded_crf_23_anywhere(self):
+        """所有渲染代码中不应再有硬编码的 CRF 23."""
+        import inspect
+
+        from video_processing.ffmpeg_utils import normalize_video
+        from video_processing.unified_render_service import UnifiedRenderService
+
+        for fn in [
+            UnifiedRenderService._execute_ffmpeg,
+            UnifiedRenderService._render_pass_through,
+            normalize_video,
+        ]:
+            src = inspect.getsource(fn)
+            # 检查没有硬编码的 "23" 作为 CRF 值
+            # 注意：行中可能有其他 "23"，只检查紧跟 -crf 之后的值
+            lines = src.split("\n")
+            for j, line in enumerate(lines):
+                if '"-crf"' in line or "'-crf'" in line:
+                    # 下一个非空行应该是常量引用而非硬编码数字
+                    for k in range(j + 1, min(j + 3, len(lines))):
+                        stripped = lines[k].strip().strip(",").strip('"').strip("'")
+                        if stripped:
+                            assert stripped != "23", f"{fn.__name__} 仍有硬编码 CRF 23"
+                            break

tests/unit/test_generated_video_creation_logic.py

@@ -381,7 +381,8 @@ class TestThumbnailInDedupHelpers:
                     thumbnail_url=pre_thumb_url,
                 )
 
-            assert result == 1
+            # #1743：返回 dict（非批次 batch_similarity=None）
+            assert result["video_count"] == 1
 
             from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
 
@@ -427,7 +428,8 @@ class TestThumbnailInDedupHelpers:
                     fps=25.0,
                 )
 
-            assert result == 1
+            # #1743：返回 dict（非批次 batch_similarity=None）
+            assert result["video_count"] == 1
 
             from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
 
@@ -474,7 +476,7 @@ class TestThumbnailInDedupHelpers:
                     fps=25.0,
                 )
 
-            assert result == 1  # 不阻断
+            assert result["video_count"] == 1  # 不阻断（#1743 dict 返回）
 
             from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
 

tests/unit/test_generation_cover.py

@@ -57,19 +57,29 @@ def test_templates_editor_no_cover_router():
             assert "generate-cover" not in getattr(route, "path", ""), "templates_editor 不应再有 generate-cover 路由"
 
 
+def _collect_route_paths(route, acc):
+    """递归收集路由路径（兼容新版 fastapi 的 _IncludedRouter 延迟包装）。"""
+    path = getattr(route, "path", None)
+    if isinstance(path, str):
+        acc.append(path)
+    # 新版 fastapi：_IncludedRouter.original_router；旧版：嵌套 .routes
+    inner = getattr(route, "original_router", None)
+    if inner is not None and hasattr(inner, "routes"):
+        for sub in inner.routes:
+            _collect_route_paths(sub, acc)
+    sub_routes = getattr(route, "routes", None)
+    if sub_routes:
+        for sub in sub_routes:
+            _collect_route_paths(sub, acc)
+
+
 def test_api_router_has_generation_cover():
     """api_router 应该包含 /api/v1/generation/generate-cover 路径"""
     from app.api.router import api_router
 
-    all_paths = []
+    all_paths: list[str] = []
     for route in api_router.routes:
-        if hasattr(route, "path"):
-            all_paths.append(route.path)
-        # 嵌套 router
-        if hasattr(route, "routes"):
-            for sub_route in route.routes:
-                if hasattr(sub_route, "path"):
-                    all_paths.append(sub_route.path)
+        _collect_route_paths(route, all_paths)
 
     # 应该能找到 generate-cover 路径
     cover_paths = [p for p in all_paths if "generate-cover" in p]
@@ -1308,7 +1318,7 @@ class TestCoverFromFinalVideo:
             call_kwargs = mock_mk.extract_frames.call_args.kwargs
             assert "rendered/final/video.mp4" in call_kwargs["video_url"]
             assert call_kwargs["strategy"] == "SpecifiedFrames"
-            assert call_kwargs["max_frames"] == 1
+            assert call_kwargs["max_frames"] == 5
             assert call_kwargs["max_retries"] == 0
             mock_persist.assert_called_once()
 

tests/unit/test_generation_preview.py

@@ -159,7 +159,6 @@ class TestCreatePreviewGenerationTaskRequest:
         assert req.template_id == "tmpl_123"
         assert req.asset_ids == ["asset_1", "asset_2"]
         assert req.title_ids == []
-        assert req.voice_ids == []
         assert req.video_title == ""
         assert req.duration == 0.0
         assert req.bgm_config == {}
@@ -175,15 +174,16 @@ class TestCreatePreviewGenerationTaskRequest:
         assert req.template_id == "tmpl_123"
         assert req.title_ids == ["title_1"]
 
-    def test_valid_request_with_voice_ids_only(self):
-        """有效请求：template_id + voice_ids"""
+    def test_valid_request_with_voice_library_id_and_asset_ids(self):
+        """有效请求：template_id + asset_ids + 统一配音 voice_library_id（#1749 替换旧 voice_ids 字段）"""
         from app.schemas.generation_task import CreatePreviewGenerationTaskRequest
 
         req = CreatePreviewGenerationTaskRequest(
             template_id="tmpl_123",
-            voice_ids=["voice_1"],
+            asset_ids=["asset_1"],
+            voice_library_id="voice_1",
         )
-        assert req.voice_ids == ["voice_1"]
+        assert req.voice_library_id == "voice_1"
 
     def test_missing_template_id_raises(self):
         """缺少 template_id 报错"""

tests/unit/test_generation_tasks.py

@@ -77,13 +77,13 @@ class TestCreateGenerationTaskUseCase:
             project_id="proj_001",
             asset_ids=["asset_1", "asset_2", "asset_3"],
             title_ids=["title_1", "title_2"],
-            voice_ids=["voice_1"],
         )
         result = use_case.execute(command)
 
         assert len(result.asset_ids) == 3
         assert len(result.title_ids) == 2
-        assert len(result.voice_ids) == 1
+        # #1749：voice_ids 已从 Command 移除（配音走 voice_library_id(s)），落库固定空列表
+        assert list(getattr(result, "voice_ids", []) or []) == []
 
     def test_create_task_with_auto_retry(self, mock_repo):
         """创建带自动重试配置的任务"""

tests/unit/test_p02_p03_fixes.py

@@ -234,12 +234,18 @@ class TestEffectiveDurationTrim:
         assert "trim=duration=7.5" in fc
 
     def test_trim_uses_min_of_duration_and_actual(self):
-        """clip.duration > actual_duration → trim 到 actual_duration。"""
+        """#1749：clip.duration > actual_duration → 目标段长为准 + tpad 末帧冻结（禁慢放/禁截断）。"""
         clip = self._make_clip("c1", duration=10.0, actual_duration=2.0)
+        # 模拟 _resolve_clips 写入的冻结标记（10s 目标 − 2s 素材 = 8s 冻结）
+        clip.config = {"_freeze_seconds": 8.0}
         svc = self._make_service([clip])
         layers = svc._group_clips_into_layers([clip])
         fc, _ = svc._build_filter_complex(layers)
+        # 素材内只取 2s，末帧冻结 8s 铺满目标 10s
         assert "trim=duration=2.0" in fc
+        assert "tpad=stop_mode=clone:stop_duration=8.0" in fc
+        # 不再有慢放（setpts 调速系数应为 1.0，即无 setpts=PTS/ 出现）
+        assert "setpts=PTS/" not in fc
 
     def test_no_trim_when_both_zero(self):
         """duration=0 且 actual_duration=0 → 不做 trim。"""