feat: 查重率百分比计算+跨项目查重 #1660 (#1675 )

Co-authored-by: xiaoxia <dev@xiaoxiajianji.com> Co-committed-by: xiaoxia <dev@xiaoxiajianji.com>
Merge pull request 'feat(dedup): 动态抽帧 + 滑动窗口时序匹配 (#1659 )' (#1673 ) from feature/1659-dynamic-keyframe-sliding-window into develop
2026-09-04 00:11:51 +08:00 · 2026-09-03 23:16:50 +08:00 · 2026-09-03 23:09:19 +08:00 · 2026-09-03 15:04:14 +00:00 · 2026-09-03 23:00:21 +08:00 · 2026-09-03 22:42:03 +08:00
23 changed files with 2826 additions and 374 deletions
@@ -0,0 +1,46 @@
+"""add video_fingerprint_chunks table for per-chunk fingerprint storage
+
+Revision ID: 063_fingerprint_chunks
+Revises: 062_edit_plan_id
+Create Date: 2026-09-03
+"""
+
+import sqlalchemy as sa
+
+from alembic import op
+
+revision = "063_fingerprint_chunks"
+down_revision = "062_edit_plan_id"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "video_fingerprint_chunks",
+        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("video_id", sa.String(36), nullable=False),
+        sa.Column("project_id", sa.String(36), nullable=False),
+        sa.Column("user_id", sa.String(36), nullable=False, server_default=""),
+        sa.Column("start_time_ms", sa.Integer, nullable=False),
+        sa.Column("end_time_ms", sa.Integer, nullable=False),
+        sa.Column("phash_binary", sa.String(16), nullable=False),
+        sa.Column("color_histogram", sa.JSON, nullable=False),
+        sa.Column("frame_count", sa.Integer, nullable=False, server_default="1"),
+        sa.Column(
+            "created_at",
+            sa.DateTime,
+            nullable=False,
+            server_default=sa.func.now(),
+        ),
+    )
+    op.create_index("ix_vfc_video_id", "video_fingerprint_chunks", ["video_id"])
+    op.create_index("ix_vfc_project_id", "video_fingerprint_chunks", ["project_id"])
+    op.create_index("ix_vfc_user_id", "video_fingerprint_chunks", ["user_id"])
+
+
+def downgrade() -> None:
+    op.drop_index("ix_vfc_user_id", table_name="video_fingerprint_chunks")
+    op.drop_index("ix_vfc_project_id", table_name="video_fingerprint_chunks")
+    op.drop_index("ix_vfc_video_id", table_name="video_fingerprint_chunks")
+    op.drop_table("video_fingerprint_chunks")
@@ -0,0 +1,25 @@
+"""add match_count and visual_similarity to generated_videos
+
+Revision ID: 064_match_count_visual_sim
+Revises: 063_fingerprint_chunks
+Create Date: 2026-09-03
+"""
+
+import sqlalchemy as sa
+
+from alembic import op
+
+revision = "064_match_count_visual_sim"
+down_revision = "063_fingerprint_chunks"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column("generated_videos", sa.Column("match_count", sa.Integer(), nullable=True, server_default="0"))
+    op.add_column("generated_videos", sa.Column("visual_similarity", sa.Float(), nullable=True, server_default="0.0"))
+
+
+def downgrade() -> None:
+    op.drop_column("generated_videos", "visual_similarity")
+    op.drop_column("generated_videos", "match_count")
@@ -687,13 +687,13 @@ def extract_voice_from_video(
        raise HTTPException(
            status_code=status.HTTP_504_GATEWAY_TIMEOUT,
            detail="视频处理超时，请尝试较短的视频",
-        )
+        ) from None
    except Exception as e:
        logger.exception("提取视频配音失败: %s", e)
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="提取配音失败，请稍后重试",
-        )
+        ) from e
    finally:
        # 清理临时文件
        if tmp_dir and Path(tmp_dir).exists():
@@ -740,7 +740,7 @@ def _find_or_create_voice_library_for_extract(*, user_id, project_repository, as
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="配音素材库创建失败",
-        )
+        ) from None


 def _get_audio_duration(audio_path: Path) -> float:
@@ -131,6 +131,7 @@ class PlanGeneratorService:
                editing_mode,
                random_selection=random_preview,
                asset_durations=asset_durations,
+                user_id=created_by_user_id,
            )

        # 5. 持久化所有 clips 并计算总时长
@@ -218,6 +219,7 @@ class PlanGeneratorService:
        *,
        random_selection: bool = False,
        asset_durations: dict[str, float] | None = None,
+        user_id: str = "",
    ) -> None:
        """按 editing_mode 将素材分配到 clips（就地修改，未持久化）.

@@ -239,6 +241,14 @@ class PlanGeneratorService:
                asset_ids = list(asset_ids)  # 复制避免修改调用方原列表
                random.shuffle(asset_ids)

+        # 查询已有视频的已用区间（跨视频避让）
+        external_used_segments = None
+        if user_id and self._clip_repo:
+            try:
+                external_used_segments = self._clip_repo.list_used_segments_by_user(user_id, limit_recent=50)
+            except Exception:
+                logger.warning("跨视频避让查询失败，回退到纯随机", exc_info=True)
+
        distribute_assets(
            clips,
            asset_ids,
@@ -246,6 +256,7 @@ class PlanGeneratorService:
            random_selection=random_selection,
            asset_durations=asset_durations,
            asset_scene_points=asset_scene_points,
+            external_used_segments=external_used_segments,
        )

    def _fetch_asset_scene_points(self, asset_ids: List[str]) -> dict[str, list[float]]:
@@ -0,0 +1,174 @@
+#!/usr/bin/env python3
+"""存量指纹重建脚本 — 为已有视频生成 video_fingerprint_chunks 分片数据。
+
+功能：
+- 查询 generated_videos 中 video_fingerprint IS NOT NULL 但尚无分片数据的视频
+- 从 OSS 下载视频 → 用新的分片算法重新计算指纹 → 写入分片表
+- 支持 --dry-run（只打印不写入）和 --batch-size（默认 50）
+- 幂等：已存在分片数据的视频跳过
+
+用法：
+    # 预览（不写入）
+    python rebuild_fingerprint_chunks.py --dry-run
+
+    # 执行重建
+    python rebuild_fingerprint_chunks.py --batch-size 50
+"""
+
+from __future__ import annotations
+
+import argparse
+import logging
+import os
+import sys
+import tempfile
+
+# 确保可以 import worker_app 和 packages
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "..", "worker"))
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", ".."))
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
+)
+logger = logging.getLogger("rebuild_fingerprint_chunks")
+
+
+def find_videos_needing_rebuild(session, batch_size: int) -> list[dict]:
+    """查询需要重建分片指纹的视频。"""
+    from sqlalchemy import and_
+
+    from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel, VideoFingerprintChunkModel
+
+    # 有 video_fingerprint 的视频
+    has_fingerprint = GeneratedVideoModel.video_fingerprint.isnot(None)
+    has_fingerprint = and_(has_fingerprint, GeneratedVideoModel.video_fingerprint != "")
+
+    # 排除已有分片数据的视频
+    subq = session.query(VideoFingerprintChunkModel.video_id).distinct().subquery()
+    no_chunks = ~GeneratedVideoModel.id.in_(subq)
+
+    videos = (
+        session.query(GeneratedVideoModel)
+        .filter(and_(has_fingerprint, no_chunks))
+        .order_by(GeneratedVideoModel.generated_at.desc())
+        .limit(batch_size)
+        .all()
+    )
+
+    return [
+        {
+            "id": v.id,
+            "project_id": v.project_id,
+            "user_id": v.user_id or "",
+            "duration": v.duration,
+        }
+        for v in videos
+    ]
+
+
+def rebuild_one(video_info: dict, dry_run: bool = False) -> int:
+    """重建单个视频的分片数据。返回写入的 chunk 数量。"""
+    from video_processing.dedup import VideoDeduplicator, _save_fingerprint_chunks
+    from worker_app.db import SessionLocal
+
+    from packages.adapters.sqlalchemy_impl.models import VideoFingerprintChunkModel
+    from packages.shared.storage import get_storage_service
+
+    video_id = video_info["id"]
+    project_id = video_info["project_id"]
+    user_id = video_info["user_id"]
+
+    if dry_run:
+        logger.info("[DRY-RUN] Would rebuild video %s (project=%s)", video_id, project_id)
+        return 0
+
+    session = SessionLocal()
+    temp_dir = tempfile.mkdtemp()
+
+    try:
+        # 再次检查幂等性
+        existing_count = (
+            session.query(VideoFingerprintChunkModel).filter(VideoFingerprintChunkModel.video_id == video_id).count()
+        )
+        if existing_count > 0:
+            logger.info("Video %s already has %d chunks, skipping", video_id, existing_count)
+            return 0
+
+        # 下载视频
+        storage_service = get_storage_service()
+        local_path = os.path.join(temp_dir, f"{video_id}.mp4")
+        storage_key = f"projects/{project_id}/generated/{video_id}/{video_id}.mp4"
+        storage_service.download_file(storage_key, local_path)
+
+        # 重新计算指纹
+        deduplicator = VideoDeduplicator()
+        fingerprint = deduplicator.compute_fingerprint(local_path)
+
+        # 写入分片表
+        _save_fingerprint_chunks(fingerprint, video_id, project_id, user_id, session)
+        session.commit()
+
+        chunk_count = len(fingerprint.chunks)
+        logger.info("Rebuilt %d chunks for video %s", chunk_count, video_id)
+        return chunk_count
+
+    except Exception as e:
+        logger.error("Failed to rebuild video %s: %s", video_id, e)
+        session.rollback()
+        return -1
+    finally:
+        session.close()
+        import shutil
+
+        shutil.rmtree(temp_dir, ignore_errors=True)
+
+
+def main():
+    parser = argparse.ArgumentParser(description="存量指纹重建脚本")
+    parser.add_argument("--dry-run", action="store_true", help="只打印不写入")
+    parser.add_argument("--batch-size", type=int, default=50, help="每批处理数量（默认 50）")
+    parser.add_argument("--total-limit", type=int, default=0, help="总处理数量限制（0=不限制）")
+    args = parser.parse_args()
+
+    from worker_app.db import SessionLocal
+
+    session = SessionLocal()
+
+    try:
+        videos = find_videos_needing_rebuild(session, args.batch_size)
+        logger.info("Found %d videos needing rebuild", len(videos))
+
+        if args.dry_run:
+            for v in videos:
+                logger.info("[DRY-RUN] Video %s | project=%s | duration=%.1fs", v["id"], v["project_id"], v["duration"])
+            return
+
+        total_chunks = 0
+        processed = 0
+        failed = 0
+
+        for v in videos:
+            if args.total_limit > 0 and processed >= args.total_limit:
+                break
+
+            result = rebuild_one(v, dry_run=False)
+            if result < 0:
+                failed += 1
+            else:
+                total_chunks += result
+                processed += 1
+
+        logger.info(
+            "Rebuild complete: processed=%d, chunks=%d, failed=%d",
+            processed,
+            total_chunks,
+            failed,
+        )
+
+    finally:
+        session.close()
+
+
+if __name__ == "__main__":
+    main()
@@ -84,7 +84,7 @@ export const extractVideoVoice = async (

  return new Promise((resolve, reject) => {
    const xhr = new XMLHttpRequest()
-    xhr.open("POST", "/api/v1/tts/extract-video-voice")
+    xhr.open("POST", "/api/v1/voices/extract-voice")

    // 携带认证 token（从 localStorage 获取，与 apiClient 拦截器一致）
    const token = localStorage.getItem("access_token")
@@ -136,8 +136,9 @@ export const MaterialVoiceTab: React.FC<MaterialVoiceTabProps> = ({
            const material = mapAssetToMaterial(asset)
            // duration 优先取顶层（后端从 metadata 提取），兜底 metadata
            const cardDuration = asset.duration || material.duration || 0
-            // AI 生成素材标识（metadata.source === "tts_job"）
-            const isAiMaterial = (asset.metadata as Record<string, unknown>)?.source === "tts_job"
+            // AI 生成素材标识：兼容旧素材（无 source 字段但有 tts_job_id）
+            const meta = asset.metadata as Record<string, unknown>
+            const isAiMaterial = meta?.source === "tts_job" || !!meta?.tts_job_id
            const isPlaying = playingId === asset.id
            const isSelected = selectedIds.has(asset.id)
            // 播放中以 audio 真实时长为准，未播放显示卡片时长
@@ -184,8 +185,10 @@ export const MaterialVoiceTab: React.FC<MaterialVoiceTabProps> = ({
                </div>

                <div className="xx-voice-info vmat-info">
-                  <div className="xx-voice-name" title={asset.name}>
-                    {asset.name}
+                  <div className="xx-voice-name-row">
+                    <div className="xx-voice-name" title={asset.name}>
+                      {asset.name}
+                    </div>
                    {isAiMaterial && <span className="vmat-ai-badge">AI</span>}
                  </div>
                  <div className="xx-voice-subtitle">
@@ -100,8 +100,24 @@ def create_video_record_and_dedup(

        generated_video.video_fingerprint = fingerprint.to_dict()

-        # (a) 历史成片查重
-        duplicate_result = deduplicator.check_duplicate(fingerprint, project_id, session)
+        # 写入分片指纹表
+        from video_processing.dedup import _save_fingerprint_chunks
+
+        try:
+            _save_fingerprint_chunks(fingerprint, video_id, project_id, user_id, session)
+        except Exception as chunk_err:
+            logger.warning("Failed to save fingerprint chunks for %s: %s", video_id, chunk_err)
+
+        # (a) 历史成片查重（跨项目全局 + 时长预过滤）
+        duration_sec = fingerprint.duration / 1000 if fingerprint.duration else 0
+        duplicate_result = deduplicator.check_duplicate(
+            fingerprint,
+            project_id,
+            session,
+            scope="user",
+            user_id=user_id,
+            duration_sec=duration_sec,
+        )

        # (b) 批次内查重（仅当有 batch_id 时）
        if not duplicate_result and batch_id:
@@ -121,17 +137,26 @@ def create_video_record_and_dedup(
            generated_video.is_duplicate = False
            generated_video.duplicate_of = None

-        # 计算重复率百分比（与项目内所有已有视频对比取最高相似度）
+        # 计算重复率百分比（跨项目全局）
        try:
-            dup_rate = deduplicator.compute_duplicate_rate(
+            rate_result = deduplicator.compute_duplicate_rate(
                fingerprint,
                project_id,
                video_id,
                session,
+                scope="user",
                user_id=user_id,
            )
-            generated_video.duplicate_rate = dup_rate
-            logger.info("Duplicate rate for %s: %.2f%%", video_id, dup_rate)
+            generated_video.duplicate_rate = rate_result["duplicate_rate"]
+            generated_video.match_count = rate_result["match_count"]
+            generated_video.visual_similarity = rate_result["visual_similarity"]
+            logger.info(
+                "Duplicate rate for %s: %.2f%% (visual_sim=%.3f, matches=%d)",
+                video_id,
+                rate_result["duplicate_rate"],
+                rate_result["visual_similarity"],
+                rate_result["match_count"],
+            )
        except Exception as rate_err:
            logger.warning("Failed to compute duplicate_rate for %s: %s", video_id, rate_err)
            generated_video.duplicate_rate = None
@@ -131,3 +131,65 @@ class SQLAlchemyEditPlanClipRepository:
            created_at=model.created_at,
            updated_at=model.updated_at,
        )
+
+    def list_used_segments_by_user(
+        self,
+        user_id: str,
+        *,
+        limit_recent: int = 50,
+    ) -> dict[str, list[tuple[float, float]]]:
+        """查询用户已有视频中已使用的素材区间（跨视频避让）.
+
+        JOIN edit_plans 表，按 created_by_user_id 过滤，只查 status='completed'
+        的 plan 下 status='rendered' 且 asset_id 非空的 clips。按 plan 的
+        created_at DESC 取最近 limit_recent 个 plan。
+
+        Returns:
+            {asset_id: [(start_time, start_time + duration), ...]}
+            空结果返回空 dict。
+        """
+        from packages.adapters.sqlalchemy_impl.models import EditPlanModel
+
+        if not user_id:
+            return {}
+
+        # 1. 查出最近 limit_recent 个已完成 plan 的 ID
+        recent_plan_ids = [
+            row[0]
+            for row in self.session.query(EditPlanModel.id)
+            .filter(
+                EditPlanModel.created_by_user_id == user_id,
+                EditPlanModel.status == "completed",
+            )
+            .order_by(EditPlanModel.created_at.desc())
+            .limit(limit_recent)
+            .all()
+        ]
+
+        if not recent_plan_ids:
+            return {}
+
+        # 2. 查这些 plan 下已渲染、有素材的 clips
+        clips = (
+            self.session.query(
+                EditPlanClipModel.asset_id,
+                EditPlanClipModel.start_time,
+                EditPlanClipModel.duration,
+            )
+            .filter(
+                EditPlanClipModel.plan_id.in_(recent_plan_ids),
+                EditPlanClipModel.status == "rendered",
+                EditPlanClipModel.asset_id != "",
+                EditPlanClipModel.asset_id.isnot(None),
+            )
+            .all()
+        )
+
+        # 3. 聚合为 {asset_id: [(start, start+duration), ...]}
+        result: dict[str, list[tuple[float, float]]] = {}
+        for asset_id, start_time, duration in clips:
+            if asset_id not in result:
+                result[asset_id] = []
+            result[asset_id].append((start_time or 0.0, (start_time or 0.0) + (duration or 0.0)))
+
+        return result
@@ -31,6 +31,8 @@ class SQLAlchemyGeneratedVideoRepository:
            is_duplicate=video.is_duplicate,
            duplicate_of=video.duplicate_of,
            duplicate_rate=video.duplicate_rate,
+            match_count=getattr(video, "match_count", 0),
+            visual_similarity=getattr(video, "visual_similarity", 0.0),
            generated_at=video.generated_at,
            created_at=video.created_at,
        )
@@ -62,6 +64,8 @@ class SQLAlchemyGeneratedVideoRepository:
            is_duplicate=getattr(model, "is_duplicate", False),
            duplicate_of=getattr(model, "duplicate_of", None),
            duplicate_rate=getattr(model, "duplicate_rate", None),
+            match_count=getattr(model, "match_count", 0) or 0,
+            visual_similarity=getattr(model, "visual_similarity", 0.0) or 0.0,
            generated_at=model.generated_at,
            created_at=model.created_at,
        )
@@ -77,6 +81,8 @@ class SQLAlchemyGeneratedVideoRepository:
        model.is_duplicate = video.is_duplicate
        model.duplicate_of = video.duplicate_of
        model.duplicate_rate = video.duplicate_rate
+        model.match_count = getattr(video, "match_count", 0)
+        model.visual_similarity = getattr(video, "visual_similarity", 0.0)
        self.session.add(model)
        self.session.commit()
        return video
@@ -85,6 +91,24 @@ class SQLAlchemyGeneratedVideoRepository:
        models = self.session.query(GeneratedVideoModel).filter(GeneratedVideoModel.project_id == project_id).all()
        return [self._to_domain(model) for model in models]

+    def list_by_user(self, user_id: str, *, duration_min: float = 0, duration_max: float = 0) -> list[GeneratedVideo]:
+        """按 user_id 查询用户所有项目的视频（跨项目查重）。
+
+        Args:
+            user_id: 用户 ID
+            duration_min: 时长下限（秒），0 表示不限
+            duration_max: 时长上限（秒），0 表示不限
+        """
+        query = self.session.query(GeneratedVideoModel).filter(
+            GeneratedVideoModel.user_id == user_id,
+        )
+        if duration_min > 0:
+            query = query.filter(GeneratedVideoModel.duration >= duration_min)
+        if duration_max > 0:
+            query = query.filter(GeneratedVideoModel.duration <= duration_max)
+        models = query.all()
+        return [self._to_domain(model) for model in models]
+
    def list_by_generation_task(self, generation_task_id: str) -> list[GeneratedVideo]:
        models = (
            self.session.query(GeneratedVideoModel)
@@ -208,6 +232,8 @@ class SQLAlchemyGeneratedVideoRepository:
            is_duplicate=getattr(model, "is_duplicate", False),
            duplicate_of=getattr(model, "duplicate_of", None),
            duplicate_rate=getattr(model, "duplicate_rate", None),
+            match_count=getattr(model, "match_count", 0) or 0,
+            visual_similarity=getattr(model, "visual_similarity", 0.0) or 0.0,
            generated_at=model.generated_at,
            created_at=model.created_at,
        )
@@ -340,6 +340,8 @@ class GeneratedVideoModel(Base):
    is_duplicate = Column(Boolean, nullable=False, default=False)
    duplicate_of = Column(String(36), nullable=True)
    duplicate_rate = Column(Float, nullable=True)
+    match_count = Column(Integer, nullable=True, default=0)
+    visual_similarity = Column(Float, nullable=True, default=0.0)


 class TitleLibraryModel(Base):
@@ -620,3 +622,20 @@ class CoverTemplateModel(Base):
    config = Column(JSON, nullable=False, default=dict)
    created_at = Column(DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc))
    updated_at = Column(DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc))
+
+
+class VideoFingerprintChunkModel(Base):
+    """分片视频指纹 — 每个视频按时间分片存储 pHash + color_histogram."""
+
+    __tablename__ = "video_fingerprint_chunks"
+
+    id = Column(String(36), primary_key=True)
+    video_id = Column(String(36), nullable=False, index=True)
+    project_id = Column(String(36), nullable=False, index=True)
+    user_id = Column(String(36), nullable=False, index=True, default="")
+    start_time_ms = Column(Integer, nullable=False)
+    end_time_ms = Column(Integer, nullable=False)
+    phash_binary = Column(String(16), nullable=False)
+    color_histogram = Column(JSON, nullable=False)
+    frame_count = Column(Integer, nullable=False, default=1)
+    created_at = Column(DateTime, nullable=False, default=lambda: datetime.now(timezone.utc))
@@ -27,6 +27,8 @@ class GeneratedVideo:
    is_duplicate: bool = False
    duplicate_of: str | None = None
    duplicate_rate: float | None = None
+    match_count: int = 0
+    visual_similarity: float = 0.0
    generated_at: datetime = field(default_factory=lambda: datetime.now(timezone.utc))
    created_at: datetime = field(default_factory=lambda: datetime.now(timezone.utc))

@@ -169,6 +169,7 @@ def distribute_assets(
    random_selection: bool = False,
    asset_durations: dict[str, float] | None = None,
    asset_scene_points: dict[str, list[float]] | None = None,
+    external_used_segments: dict[str, list[tuple[float, float]]] | None = None,
 ) -> None:
    """按 editing_mode 将素材分配到 clips（就地修改）.

@@ -188,6 +189,7 @@ def distribute_assets(
        random_selection: 是否随机选择素材（用于预览生成）
        asset_durations: 素材 ID -> 时长（秒）映射，用于设置 start_time
        asset_scene_points: 素材 ID -> 场景切换点列表（metadata 缓存）
+        external_used_segments: 跨视频已用区间（来自其他视频的 clips），注入到分配逻辑中避让
    """
    if not asset_ids or not clips:
        return
@@ -198,16 +200,16 @@ def distribute_assets(
        random.shuffle(asset_ids)

    if editing_mode == EditingMode.ONE_TAKE.value:
-        _distribute_one_take(clips, asset_ids, asset_durations, asset_scene_points)
+        _distribute_one_take(clips, asset_ids, asset_durations, asset_scene_points, external_used_segments)
    elif editing_mode == EditingMode.PIP.value:
-        _distribute_pip(clips, asset_ids, asset_durations, asset_scene_points)
+        _distribute_pip(clips, asset_ids, asset_durations, asset_scene_points, external_used_segments)
    elif editing_mode == EditingMode.VOICE_OVER.value:
-        _distribute_voice_over(clips, asset_ids, asset_durations, asset_scene_points)
+        _distribute_voice_over(clips, asset_ids, asset_durations, asset_scene_points, external_used_segments)
    elif editing_mode == EditingMode.VOICE_PIP.value:
-        _distribute_voice_pip(clips, asset_ids, asset_durations, asset_scene_points)
+        _distribute_voice_pip(clips, asset_ids, asset_durations, asset_scene_points, external_used_segments)
    else:
        # 未知模式，退化为 one_take
-        _distribute_one_take(clips, asset_ids, asset_durations, asset_scene_points)
+        _distribute_one_take(clips, asset_ids, asset_durations, asset_scene_points, external_used_segments)


 def _resolve_start_time(
@@ -248,9 +250,12 @@ def _distribute_one_take(
    asset_ids: List[str],
    asset_durations: dict[str, float] | None = None,
    asset_scene_points: dict[str, list[float]] | None = None,
+    external_used_segments: dict[str, list[tuple[float, float]]] | None = None,
 ) -> None:
    """ONE_TAKE: 素材按顺序依次分配给 main 类型 clips."""
-    used_segments: dict[str, list[tuple[float, float]]] = {}
+    used_segments: dict[str, list[tuple[float, float]]] = (
+        {k: list(v) for k, v in external_used_segments.items()} if external_used_segments else {}
+    )
    main_clips = [c for c in clips if c.clip_type == ClipType.MAIN.value]
    for i, clip in enumerate(main_clips):
        if i < len(asset_ids):
@@ -271,9 +276,12 @@ def _distribute_pip(
    asset_ids: List[str],
    asset_durations: dict[str, float] | None = None,
    asset_scene_points: dict[str, list[float]] | None = None,
+    external_used_segments: dict[str, list[tuple[float, float]]] | None = None,
 ) -> None:
    """PIP: 第1个素材→main(全屏背景)，其余→overlay clips."""
-    used_segments: dict[str, list[tuple[float, float]]] = {}
+    used_segments: dict[str, list[tuple[float, float]]] = (
+        {k: list(v) for k, v in external_used_segments.items()} if external_used_segments else {}
+    )
    # 第1个素材 → main clip
    main_clips = [c for c in clips if c.clip_type == ClipType.MAIN.value]
    if main_clips and asset_ids:
@@ -310,9 +318,12 @@ def _distribute_voice_over(
    asset_ids: List[str],
    asset_durations: dict[str, float] | None = None,
    asset_scene_points: dict[str, list[float]] | None = None,
+    external_used_segments: dict[str, list[tuple[float, float]]] | None = None,
 ) -> None:
    """VOICE_OVER: 素材→main clips (B-roll)."""
-    used_segments: dict[str, list[tuple[float, float]]] = {}
+    used_segments: dict[str, list[tuple[float, float]]] = (
+        {k: list(v) for k, v in external_used_segments.items()} if external_used_segments else {}
+    )
    main_clips = [c for c in clips if c.clip_type == ClipType.MAIN.value]
    for i, clip in enumerate(main_clips):
        if i < len(asset_ids):
@@ -333,9 +344,12 @@ def _distribute_voice_pip(
    asset_ids: List[str],
    asset_durations: dict[str, float] | None = None,
    asset_scene_points: dict[str, list[float]] | None = None,
+    external_used_segments: dict[str, list[tuple[float, float]]] | None = None,
 ) -> None:
    """VOICE_PIP: 第1个→background, 第2个→corner_voice, 其余→b_roll."""
-    used_segments: dict[str, list[tuple[float, float]]] = {}
+    used_segments: dict[str, list[tuple[float, float]]] = (
+        {k: list(v) for k, v in external_used_segments.items()} if external_used_segments else {}
+    )
    bg_clips = [c for c in clips if c.clip_type == "background"]
    voice_clips = [c for c in clips if c.clip_type == "corner_voice"]
    broll_clips = [c for c in clips if c.clip_type == "b_roll"]
@@ -0,0 +1,334 @@
+"""Tests for Issue #1670 — 跨视频片段避让（生成前注入已用区间）."""
+
+from __future__ import annotations
+
+from datetime import datetime, timezone
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from packages.adapters.sqlalchemy_impl.edit_plan_clip_repository import (
+    SQLAlchemyEditPlanClipRepository,
+)
+from packages.domain.edit_plan_clip import EditPlanClip, EditPlanClipStatus
+from packages.domain.plan_generator_utils import (
+    _distribute_one_take,
+    distribute_assets,
+)
+
+# ── Repository 层测试 ─────────────────────────────────────────────────────────
+
+
+class TestListUsedSegmentsByUser:
+    """测试 list_used_segments_by_user 方法."""
+
+    def _make_repo(self, session_mock):
+        return SQLAlchemyEditPlanClipRepository(session_mock)
+
+    def test_empty_user_id_returns_empty_dict(self):
+        """空 user_id 直接返回空 dict，不查 DB."""
+        session = MagicMock()
+        repo = self._make_repo(session)
+        result = repo.list_used_segments_by_user("")
+        assert result == {}
+        session.query.assert_not_called()
+
+    def test_no_completed_plans_returns_empty_dict(self):
+        """用户没有已完成的 plan 时返回空 dict."""
+        session = MagicMock()
+        # Mock plan query returns empty
+        plan_query = MagicMock()
+        plan_query.filter.return_value = plan_query
+        plan_query.order_by.return_value = plan_query
+        plan_query.limit.return_value = plan_query
+        plan_query.all.return_value = []
+        session.query.return_value = plan_query
+
+        repo = self._make_repo(session)
+        result = repo.list_used_segments_by_user("user_123")
+        assert result == {}
+
+    def test_aggregates_clips_from_multiple_plans(self):
+        """从多个已完成 plan 的 clips 聚合已用区间."""
+        session = MagicMock()
+
+        # Mock plan query: 2 completed plans
+        plan_query = MagicMock()
+        plan_query.filter.return_value = plan_query
+        plan_query.order_by.return_value = plan_query
+        plan_query.limit.return_value = plan_query
+        plan_query.all.return_value = [("plan_1",), ("plan_2",)]
+        session.query.return_value = plan_query
+
+        # Mock clip query: clips from both plans
+        clip_query = MagicMock()
+        clip_query.filter.return_value = clip_query
+        clip_query.all.return_value = [
+            ("asset_A", 0.0, 5.0),  # plan_1, asset A: 0~5s
+            ("asset_A", 10.0, 3.0),  # plan_1, asset A: 10~13s
+            ("asset_B", 2.0, 4.0),  # plan_2, asset B: 2~6s
+        ]
+        # Second session.query call is for clips
+        session.query.side_effect = [plan_query, clip_query]
+
+        repo = self._make_repo(session)
+        result = repo.list_used_segments_by_user("user_123")
+
+        assert "asset_A" in result
+        assert len(result["asset_A"]) == 2
+        assert result["asset_A"][0] == (0.0, 5.0)
+        assert result["asset_A"][1] == (10.0, 13.0)
+        assert "asset_B" in result
+        assert result["asset_B"][0] == (2.0, 6.0)
+
+    def test_respects_limit_recent_parameter(self):
+        """limit_recent 参数限制查询的 plan 数量."""
+        session = MagicMock()
+
+        plan_query = MagicMock()
+        plan_query.filter.return_value = plan_query
+        plan_query.order_by.return_value = plan_query
+        plan_query.limit.return_value = plan_query
+        plan_query.all.return_value = [("plan_1",)]
+        session.query.return_value = plan_query
+
+        clip_query = MagicMock()
+        clip_query.filter.return_value = clip_query
+        clip_query.all.return_value = [("asset_X", 1.0, 2.0)]
+        session.query.side_effect = [plan_query, clip_query]
+
+        repo = self._make_repo(session)
+        result = repo.list_used_segments_by_user("user_123", limit_recent=10)
+
+        # Verify limit was called with the parameter
+        plan_query.limit.assert_called_once_with(10)
+        assert "asset_X" in result
+
+
+# ── Domain 层测试 ─────────────────────────────────────────────────────────────
+
+
+class TestDistributeAssetsWithExternalSegments:
+    """测试 distribute_assets 传入 external_used_segments 的行为."""
+
+    def _make_clips(self, count: int, duration: float = 3.0) -> list[EditPlanClip]:
+        """创建指定数量的 MAIN 类型 clips."""
+        return [
+            EditPlanClip(
+                id=f"clip_{i}",
+                plan_id="plan_1",
+                clip_type="main",
+                order=i,
+                template_clip_config_id="",
+                asset_id="",
+                text_content="",
+                start_time=0.0,
+                duration=duration,
+                status=EditPlanClipStatus.PENDING,
+            )
+            for i in range(count)
+        ]
+
+    def test_external_used_segments_none_backward_compatible(self):
+        """external_used_segments=None 时行为不变（向后兼容）."""
+        clips = self._make_clips(3)
+        asset_ids = ["asset_1", "asset_2", "asset_3"]
+        asset_durations = {aid: 30.0 for aid in asset_ids}
+
+        # Should not raise
+        distribute_assets(
+            clips,
+            asset_ids,
+            "one_take",
+            asset_durations=asset_durations,
+            external_used_segments=None,
+        )
+
+        # All clips should have assets assigned
+        for clip in clips:
+            assert clip.asset_id != ""
+
+    def test_external_used_segments_avoids_existing_ranges(self):
+        """传入 external_used_segments 后，新分配的 start_time 避开已有区间."""
+        clips = self._make_clips(2, duration=3.0)
+        asset_ids = ["asset_1"]
+        asset_durations = {"asset_1": 30.0}
+
+        # Pretend asset_1 0~10s is already used by another video
+        external = {"asset_1": [(0.0, 10.0)]}
+
+        # Run multiple times to check that start_time always avoids 0~10s
+        # (with some randomness, but the avoidance should be consistent)
+        for _ in range(10):
+            test_clips = self._make_clips(1, duration=3.0)
+            distribute_assets(
+                test_clips,
+                asset_ids,
+                "one_take",
+                asset_durations=asset_durations,
+                external_used_segments=external,
+            )
+            start = test_clips[0].start_time
+            # Start time + duration (3s) should not overlap with 0~10
+            # i.e., start >= 10.0 or start + 3 <= 0.0 (impossible since start >= 0)
+            assert (
+                start >= 10.0 or start + 3.0 <= 0.0 or start >= 10.0
+            ), f"start_time {start} overlaps with existing segment 0~10"
+
+    def test_external_used_segments_deep_copy(self):
+        """external_used_segments 会被深拷贝，不会修改外部数据."""
+        external = {"asset_1": [(0.0, 5.0)]}
+        original = {"asset_1": [(0.0, 5.0)]}
+
+        clips = self._make_clips(1, duration=2.0)
+        asset_ids = ["asset_1"]
+        asset_durations = {"asset_1": 20.0}
+
+        distribute_assets(
+            clips,
+            asset_ids,
+            "one_take",
+            asset_durations=asset_durations,
+            external_used_segments=external,
+        )
+
+        # External dict should be unchanged
+        assert external == original
+
+    def test_empty_external_used_segments_same_as_none(self):
+        """空 dict 的 external_used_segments 行为与 None 相同."""
+        clips = self._make_clips(2, duration=3.0)
+        asset_ids = ["asset_1", "asset_2"]
+        asset_durations = {aid: 30.0 for aid in asset_ids}
+
+        # Should not raise and should assign assets normally
+        distribute_assets(
+            clips,
+            asset_ids,
+            "one_take",
+            asset_durations=asset_durations,
+            external_used_segments={},
+        )
+        for clip in clips:
+            assert clip.asset_id != ""
+
+
+# ── Service 层测试 ────────────────────────────────────────────────────────────
+
+
+class TestServiceLayerIntegration:
+    """测试 _distribute_assets 在 service 层的查询逻辑."""
+
+    def _make_service(self, clip_repo_mock, asset_repo_mock=None):
+        """创建 PlanGeneratorService 并注入 mock repos."""
+
+        from apps.api.app.services.plan_generator_service import PlanGeneratorService
+
+        with (
+            patch("apps.api.app.services.plan_generator_service.SQLAlchemyEditPlanRepository"),
+            patch(
+                "apps.api.app.services.plan_generator_service.SQLAlchemyEditPlanClipRepository",
+                return_value=clip_repo_mock,
+            ),
+        ):
+            db = MagicMock()
+            svc = PlanGeneratorService(db, asset_repo=asset_repo_mock)
+            svc._clip_repo = clip_repo_mock
+        return svc
+
+    def _make_clip(self):
+        return EditPlanClip(
+            id="clip_1",
+            plan_id="plan_1",
+            clip_type="main",
+            order=0,
+            template_clip_config_id="",
+            asset_id="",
+            text_content="",
+            start_time=0.0,
+            duration=3.0,
+            status=EditPlanClipStatus.PENDING,
+        )
+
+    def test_query_called_with_user_id(self):
+        """有 user_id 时调用 list_used_segments_by_user."""
+        clip_repo = MagicMock()
+        clip_repo.list_used_segments_by_user.return_value = {"asset_A": [(0.0, 5.0)]}
+        asset_repo = MagicMock()
+        asset_repo.get.return_value = None  # smart_match fallback
+
+        svc = self._make_service(clip_repo, asset_repo)
+        clips = [self._make_clip()]
+
+        svc._distribute_assets(
+            clips,
+            ["asset_A"],
+            "one_take",
+            asset_durations={"asset_A": 30.0},
+            user_id="user_123",
+        )
+
+        clip_repo.list_used_segments_by_user.assert_called_once_with("user_123", limit_recent=50)
+
+    def test_query_not_called_without_user_id(self):
+        """无 user_id 时不调用查询."""
+        clip_repo = MagicMock()
+        asset_repo = MagicMock()
+        asset_repo.get.return_value = None
+
+        svc = self._make_service(clip_repo, asset_repo)
+        clips = [self._make_clip()]
+
+        svc._distribute_assets(
+            clips,
+            ["asset_A"],
+            "one_take",
+            asset_durations={"asset_A": 30.0},
+            user_id="",
+        )
+
+        clip_repo.list_used_segments_by_user.assert_not_called()
+
+    def test_query_failure_does_not_block_generation(self):
+        """查询失败时不阻塞生成，回退到纯随机."""
+        clip_repo = MagicMock()
+        clip_repo.list_used_segments_by_user.side_effect = Exception("DB error")
+        asset_repo = MagicMock()
+        asset_repo.get.return_value = None
+
+        svc = self._make_service(clip_repo, asset_repo)
+        clips = [self._make_clip()]
+
+        # Should not raise
+        svc._distribute_assets(
+            clips,
+            ["asset_A"],
+            "one_take",
+            asset_durations={"asset_A": 30.0},
+            user_id="user_123",
+        )
+
+        # Clip should still get an asset assigned (fallback to random)
+        assert clips[0].asset_id == "asset_A"
+
+    def test_preview_and_final_both_query(self):
+        """预览和正式生成都触发查询."""
+        for random_selection in [True, False]:
+            clip_repo = MagicMock()
+            clip_repo.list_used_segments_by_user.return_value = {}
+            asset_repo = MagicMock()
+            asset_repo.get.return_value = None
+
+            svc = self._make_service(clip_repo, asset_repo)
+            clips = [self._make_clip()]
+
+            svc._distribute_assets(
+                clips,
+                ["asset_A"],
+                "one_take",
+                random_selection=random_selection,
+                asset_durations={"asset_A": 30.0},
+                user_id="user_123",
+            )
+
+            clip_repo.list_used_segments_by_user.assert_called_once()
@@ -285,8 +285,10 @@ class TestVideoDeduplicatorCheckDuplicate:
            result = deduplicator.check_duplicate(fingerprint, "proj-1", mock_session)
            assert result is not None
            assert result["duplicate"] is True
-            assert result["similarity"] == 1.0  # distance=0 → 1.0
-            assert result["reason"] == "phash_similar"
+            assert result["similarity"] == pytest.approx(
+                0.85, abs=0.01
+            )  # combined: 0.7*1.0 + 0.3*0.5 (no hist fallback)
+            assert result["reason"] == "phash_histogram_fusion"
        finally:
            self._restore_repo(mod, orig)

@@ -425,8 +427,11 @@ class TestVideoDeduplicatorCheckDuplicate:
            result = deduplicator.check_duplicate(fingerprint, "proj-1", mock_session)
            assert result is not None
            assert result["duplicate"] is True
-            # similarity = 1.0 - (1 / 64) = 0.984375
-            assert abs(result["similarity"] - (1.0 - 1.0 / 64)) < 1e-6
+            # 新算法: median_distance=1, phash_sim=1-1/64=0.984375
+            # 无直方图 → hist_sim=0.5(fallback)
+            # combined = 0.7*0.984375 + 0.3*0.5 = 0.839062
+            expected_sim = 0.7 * (1.0 - 1.0 / 64) + 0.3 * 0.5
+            assert abs(result["similarity"] - expected_sim) < 1e-6
        finally:
            self._restore_repo(mod, orig)

@@ -456,7 +461,9 @@ class TestVideoDeduplicatorCheckDuplicate:
            result = deduplicator.check_duplicate(fingerprint, "proj-1", mock_session)
            assert result is not None
            assert result["duplicate"] is True
-            assert result["similarity"] == 1.0  # avg_distance = 0
+            # 新算法: median_distance=0, phash_sim=1.0, hist_sim=0.5(fallback)
+            # combined = 0.7*1.0 + 0.3*0.5 = 0.85
+            assert result["similarity"] == pytest.approx(0.85, abs=0.01)
        finally:
            self._restore_repo(mod, orig)

@@ -539,7 +546,7 @@ class TestVideoDeduplicatorCheckBatchDuplicate:
            result = deduplicator.check_batch_duplicate(fingerprint, "batch-1", "vid-self", mock_session)
            assert result is not None
            assert result["duplicate"] is True
-            assert result["reason"] == "batch_phash_similar"
+            assert result["reason"] == "batch_phash_histogram_fusion"
        finally:
            self._restore_repo(mod, orig)

@@ -43,7 +43,11 @@ class TestDedupHelpersUserIdPassthrough:
        mock_deduplicator = MagicMock()
        mock_deduplicator.compute_fingerprint.return_value = mock_fingerprint
        mock_deduplicator.check_duplicate.return_value = None
-        mock_deduplicator.compute_duplicate_rate.return_value = 42.5
+        mock_deduplicator.compute_duplicate_rate.return_value = {
+            "duplicate_rate": 42.5,
+            "visual_similarity": 0.7,
+            "match_count": 2,
+        }

        with (
            patch(
@@ -85,7 +89,11 @@ class TestDedupHelpersUserIdPassthrough:
        mock_deduplicator = MagicMock()
        mock_deduplicator.compute_fingerprint.return_value = mock_fingerprint
        mock_deduplicator.check_duplicate.return_value = None
-        mock_deduplicator.compute_duplicate_rate.return_value = 0.0
+        mock_deduplicator.compute_duplicate_rate.return_value = {
+            "duplicate_rate": 0.0,
+            "visual_similarity": 0.0,
+            "match_count": 0,
+        }

        with (
            patch(
@@ -124,7 +132,11 @@ class TestDedupHelpersUserIdPassthrough:
        mock_deduplicator = MagicMock()
        mock_deduplicator.compute_fingerprint.return_value = mock_fingerprint
        mock_deduplicator.check_duplicate.return_value = None
-        mock_deduplicator.compute_duplicate_rate.return_value = 78.5
+        mock_deduplicator.compute_duplicate_rate.return_value = {
+            "duplicate_rate": 78.5,
+            "visual_similarity": 0.85,
+            "match_count": 3,
+        }

        with (
            patch(
@@ -181,70 +181,68 @@ class TestVideoFingerprint:
        assert d["color_histograms"] == []


-class TestAverageHistogramSimilarity:
-    """_average_histogram_similarity 直方图相似度测试."""
+class TestBhattacharyyaCoefficient:
+    """_bhattacharyya_coefficient Bhattacharyya 系数测试."""

    def test_identical_histograms(self):
-        """完全相同的直方图相似度为1.0."""
-        hist = [[0.5, 0.5, 0.0], [0.3, 0.4, 0.3]]
-        sim = VideoDeduplicator._average_histogram_similarity(hist, hist)
-        assert sim == pytest.approx(1.0)
+        """完全相同的直方图系数为1.0."""
+        hist = [0.5, 0.5, 0.0, 0.3]
+        bc = VideoDeduplicator._bhattacharyya_coefficient(hist, hist)
+        # Σ √(a[i]*a[i]) = Σ a[i] = 1.0 (normalized)
+        assert bc == pytest.approx(sum(h for h in hist))

-    def test_empty_first_list(self):
+    def test_zero_histograms(self):
+        """全零直方图系数为0."""
+        bc = VideoDeduplicator._bhattacharyya_coefficient([0.0, 0.0], [0.0, 0.0])
+        assert bc == 0.0
+
+    def test_orthogonal_histograms(self):
+        """正交直方图（无重叠）系数为0."""
+        bc = VideoDeduplicator._bhattacharyya_coefficient([1.0, 0.0], [0.0, 1.0])
+        assert bc == pytest.approx(0.0)
+
+    def test_different_lengths(self):
+        """不同长度直方图取最小长度对齐."""
+        bc = VideoDeduplicator._bhattacharyya_coefficient([1.0, 1.0, 0.0, 0.0], [1.0, 1.0])
+        # 对齐到前2维: √(1*1) + √(1*1) = 2.0
+        assert bc == pytest.approx(2.0)
+
+    def test_known_value(self):
+        """已知值验证."""
+        # [0.25, 0.25, 0.25, 0.25] vs [0.25, 0.25, 0.25, 0.25]
+        # BC = 4 * √(0.25 * 0.25) = 4 * 0.25 = 1.0
+        hist = [0.25, 0.25, 0.25, 0.25]
+        bc = VideoDeduplicator._bhattacharyya_coefficient(hist, hist)
+        assert bc == pytest.approx(1.0)
+
+
+class TestComputeHistogramSimilarity:
+    """_compute_histogram_similarity 多帧直方图相似度测试."""
+
+    def test_identical_histogram_groups(self):
+        """完全相同的两组直方图."""
+        hist = [[0.5, 0.5], [0.3, 0.4]]
+        sim = VideoDeduplicator._compute_histogram_similarity(hist, hist)
+        # Each hist finds best match = itself
+        assert sim > 0.0
+
+    def test_empty_first(self):
        """第一组为空返回0."""
-        sim = VideoDeduplicator._average_histogram_similarity([], [[0.5, 0.5]])
-        assert sim == 0.0
+        assert VideoDeduplicator._compute_histogram_similarity([], [[0.5]]) == 0.0

-    def test_empty_second_list(self):
+    def test_empty_second(self):
        """第二组为空返回0."""
-        sim = VideoDeduplicator._average_histogram_similarity([[0.5, 0.5]], [])
-        assert sim == 0.0
+        assert VideoDeduplicator._compute_histogram_similarity([[0.5]], []) == 0.0

    def test_both_empty(self):
        """两组都为空返回0."""
-        sim = VideoDeduplicator._average_histogram_similarity([], [])
-        assert sim == 0.0
+        assert VideoDeduplicator._compute_histogram_similarity([], []) == 0.0

-    def test_orthogonal_histograms(self):
-        """正交直方图相似度为0."""
-        # [1, 0] 和 [0, 1] 正交
-        sim = VideoDeduplicator._average_histogram_similarity([[1.0, 0.0]], [[0.0, 1.0]])
-        assert sim == pytest.approx(0.0)
-
-    def test_partial_similarity(self):
-        """部分相似."""
-        # [1, 1] 和 [1, 0] 的余弦相似度 = 1/√2 ≈ 0.707
-        sim = VideoDeduplicator._average_histogram_similarity([[1.0, 1.0]], [[1.0, 0.0]])
-        assert sim == pytest.approx(1.0 / (2**0.5), rel=0.01)
-
-    def test_multiple_frames_best_match(self):
+    def test_best_match_selection(self):
        """多帧时取最佳匹配."""
-        # 第一帧完全不同，第二帧完全相同 → 平均 best = (0 + 1) / 2 = 0.5
-        sim = VideoDeduplicator._average_histogram_similarity(
-            [[1.0, 0.0], [0.0, 1.0]],
-            [[0.0, 1.0]],  # 只有一帧，和第一帧0相似，和第二帧1相似
-        )
-        # 第一帧最佳匹配=0，第二帧最佳匹配=1，平均=0.5
-        assert sim == pytest.approx(0.5)
-
-    def test_zero_norm_histogram_skipped(self):
-        """零范数直方图被跳过."""
-        sim = VideoDeduplicator._average_histogram_similarity([[0.0, 0.0]], [[1.0, 1.0]])
-        # 第一组的零范数被跳过，similarities为空，返回0
-        assert sim == 0.0
-
-    def test_different_length_histograms(self):
-        """不同长度的直方图取最小长度对齐."""
-        sim = VideoDeduplicator._average_histogram_similarity(
-            [[1.0, 1.0, 0.0, 0.0]],  # 4维
-            [[1.0, 1.0]],  # 2维
-        )
-        # 对齐到前2维，都是[1,1]，相似度1.0
+        # ha[0] 与 hb[0] 正交，与 hb[1] 完全相同
+        a = [[1.0, 0.0]]
+        b = [[0.0, 1.0], [1.0, 0.0]]
+        sim = VideoDeduplicator._compute_histogram_similarity(a, b)
+        # Best match for [1,0]: max(BC([1,0],[0,1]), BC([1,0],[1,0])) = max(0, 1) = 1
        assert sim == pytest.approx(1.0)
-
-    def test_similarity_in_zero_one_range(self):
-        """相似度在[0, 1]范围内."""
-        hist_a = [np.random.rand(96).tolist() for _ in range(5)]
-        hist_b = [np.random.rand(96).tolist() for _ in range(5)]
-        sim = VideoDeduplicator._average_histogram_similarity(hist_a, hist_b)
-        assert 0.0 <= sim <= 1.0
@@ -0,0 +1,532 @@
+"""Issue #1659: 动态抽帧 + 滑动窗口时序匹配 单元测试.
+
+覆盖：
+- detect_keyframe_timestamps: 关键帧检测（mock cv2）
+- find_duplicate_segments: 滑动窗口时序匹配
+- DuplicateSegment 数据类
+- _bhattacharyya_coefficient / _compute_histogram_similarity
+- 帧匹配比例条件 (match_ratio < 0.7 → 跳过)
+- 中位数 vs 均值（抵抗异常值）
+- 向后兼容（无分片数据时不崩溃）
+"""
+
+from __future__ import annotations
+
+import sys
+from unittest.mock import MagicMock, patch
+
+
+def _mock_module(**attrs):
+    """Create a mock module with __spec__ to avoid AttributeError."""
+    m = MagicMock()
+    m.__spec__ = None
+    for k, v in attrs.items():
+        setattr(m, k, v)
+    return m
+
+
+# ── Module-level setup: mock deps, import dedup, then restore sys.modules ──
+_SAVED_MODULES_KEYS = set(sys.modules.keys())
+_SAVED_MODULES_VALUES = {
+    k: sys.modules.get(k)
+    for k in [
+        "cv2",
+        "celery",
+        "sqlalchemy",
+        "sqlalchemy.orm",
+        "sqlalchemy.engine",
+        "sqlalchemy.ext",
+        "sqlalchemy.ext.declarative",
+        "worker_app.db",
+        "worker_app.celery_app",
+        "worker_app.core.config",
+        "packages.adapters.sqlalchemy_impl.session",
+        "packages.adapters.sqlalchemy_impl.generated_video_repository",
+        "packages.adapters.sqlalchemy_impl.models",
+        "packages.shared.config",
+        "packages.shared.storage",
+    ]
+}
+
+sys.modules["cv2"] = _mock_module()
+
+_mock_celery = MagicMock()
+_mock_celery.Task = MagicMock
+_mock_celery.Celery = MagicMock
+_mock_celery.__spec__ = None
+sys.modules["celery"] = _mock_celery
+
+_mock_sqla = MagicMock()
+_mock_sqla.__path__ = []
+_mock_sqla.__spec__ = None
+sys.modules["sqlalchemy"] = _mock_sqla
+
+_mock_sqla_orm = MagicMock()
+_mock_sqla_orm.__path__ = []
+_mock_sqla_orm.__spec__ = None
+_mock_sqla_orm.Session = MagicMock
+sys.modules["sqlalchemy.orm"] = _mock_sqla_orm
+sys.modules["sqlalchemy.engine"] = _mock_module()
+sys.modules["sqlalchemy.ext"] = _mock_module()
+sys.modules["sqlalchemy.ext.declarative"] = _mock_module()
+
+sys.modules["worker_app.db"] = _mock_module(SessionLocal=MagicMock())
+sys.modules["worker_app.celery_app"] = _mock_module(celery_app=MagicMock())
+sys.modules["worker_app.core.config"] = _mock_module(get_settings=MagicMock(return_value=MagicMock()))
+
+sys.modules["packages.adapters.sqlalchemy_impl.session"] = _mock_module(
+    Base=MagicMock(),
+    build_engine=MagicMock(),
+    build_session_factory=MagicMock(),
+    ensure_database_exists=MagicMock(),
+    initialize_database=MagicMock(),
+)
+sys.modules["packages.adapters.sqlalchemy_impl.generated_video_repository"] = _mock_module(
+    SQLAlchemyGeneratedVideoRepository=MagicMock
+)
+sys.modules["packages.adapters.sqlalchemy_impl.models"] = _mock_module(
+    VideoFingerprintChunkModel=MagicMock,
+    GeneratedVideoModel=MagicMock,
+)
+sys.modules["packages.shared.config"] = _mock_module(get_shared_settings=MagicMock(return_value=MagicMock()))
+sys.modules["packages.shared.storage"] = _mock_module()
+
+# Save a reference to the dedup module for use in tests (after sys.modules restore)
+import video_processing.dedup as _dedup_mod
+from video_processing.dedup import (  # noqa: E402
+    DUPLICATE_THRESHOLD,
+    HISTOGRAM_WEIGHT,
+    LONG_VIDEO_DURATION_THRESHOLD_SEC,
+    MATCH_RATIO_THRESHOLD,
+    MAX_GAP,
+    MAX_KEYFRAMES,
+    MIN_CONSECUTIVE_MATCHES,
+    MIN_KEYFRAME_INTERVAL_SEC,
+    MIN_KEYFRAMES,
+    PHASH_WEIGHT,
+    SCENE_CHANGE_THRESHOLD,
+    SEGMENT_MATCH_THRESHOLD,
+    DuplicateSegment,
+    FingerprintChunk,
+    VideoDeduplicator,
+    VideoFingerprint,
+    detect_keyframe_timestamps,
+    find_duplicate_segments,
+    hamming_distance,
+)
+
+# ── Restore sys.modules immediately after import ──
+for _key in list(sys.modules.keys()):
+    if _key not in _SAVED_MODULES_KEYS:
+        del sys.modules[_key]
+for _key, _value in _SAVED_MODULES_VALUES.items():
+    if _value is not None:
+        sys.modules[_key] = _value
+    elif _key in sys.modules:
+        del sys.modules[_key]
+del _SAVED_MODULES_KEYS, _SAVED_MODULES_VALUES, _key, _value
+
+
+# ── Helper ──────────────────────────────────────────────────────
+
+
+def _make_chunk(start_ms: int, end_ms: int, phash: str, hist: list[float] | None = None) -> FingerprintChunk:
+    """创建测试用 FingerprintChunk."""
+    return FingerprintChunk(
+        start_time_ms=start_ms,
+        end_time_ms=end_ms,
+        phash_binary=phash,
+        color_histogram=hist or [0.1] * 96,
+        frame_count=1,
+    )
+
+
+# ── TestDuplicateSegment ────────────────────────────────────────
+
+
+class TestDuplicateSegment:
+    """DuplicateSegment 数据类测试."""
+
+    def test_creation(self):
+        """正常创建."""
+        seg = DuplicateSegment(
+            query_start_ms=1000,
+            query_end_ms=5000,
+            target_start_ms=2000,
+            target_end_ms=6000,
+            avg_distance=3.5,
+        )
+        assert seg.query_start_ms == 1000
+        assert seg.avg_distance == 3.5
+
+    def test_fields(self):
+        """所有字段可访问."""
+        seg = DuplicateSegment(0, 1000, 500, 1500, 2.0)
+        assert seg.query_end_ms == 1000
+        assert seg.target_start_ms == 500
+        assert seg.target_end_ms == 1500
+
+
+# ── TestDetectKeyframeTimestamps ────────────────────────────────
+
+
+class TestDetectKeyframeTimestamps:
+    """detect_keyframe_timestamps 关键帧检测测试.
+
+    由于 cv2 在单元测试环境中是 mock，这里只测试边界条件。
+    完整的视频处理测试在集成测试中进行。
+    """
+
+    def test_cannot_open_video_raises(self):
+        """无法打开视频时抛出 RuntimeError."""
+        cv2_mock = _dedup_mod.cv2
+        mock_cap = MagicMock()
+        mock_cap.isOpened.return_value = False
+        cv2_mock.VideoCapture.return_value = mock_cap
+
+        import pytest
+
+        with pytest.raises(RuntimeError, match="Cannot open video"):
+            detect_keyframe_timestamps("/fake/path.mp4")
+
+    def test_zero_duration_returns_empty(self):
+        """视频时长为 0 时返回空列表."""
+        cv2_mock = _dedup_mod.cv2
+        mock_cap = MagicMock()
+        mock_cap.isOpened.return_value = True
+        # cv2.CAP_PROP_FPS etc. are Mock objects; configure get() to return 0 for frame_count
+        mock_cap.get.return_value = 0
+        mock_cap.read.return_value = (False, None)
+        cv2_mock.VideoCapture.return_value = mock_cap
+
+        result = detect_keyframe_timestamps("/fake/zero.mp4")
+        assert result == []
+
+    def test_function_signature(self):
+        """验证函数签名和默认参数."""
+        import inspect
+
+        sig = inspect.signature(detect_keyframe_timestamps)
+        params = sig.parameters
+        assert "video_path" in params
+        assert "min_interval_sec" in params
+        assert "max_frames" in params
+        assert "min_frames" in params
+        # 默认值
+        assert params["min_interval_sec"].default == 1.0
+        assert params["max_frames"].default == 30
+        assert params["min_frames"].default == 5
+
+
+# ── TestFindDuplicateSegments ───────────────────────────────────
+
+
+class TestFindDuplicateSegments:
+    """find_duplicate_segments 滑动窗口时序匹配测试."""
+
+    def test_identical_chunks_full_match(self):
+        """两组完全相同的 chunks → 整段匹配."""
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, "aaaaaaaaaaaaaaaa") for i in range(10)]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, "aaaaaaaaaaaaaaaa") for i in range(10)]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        assert len(segments) >= 1
+        # 应该覆盖大部分范围
+        total_query_range = segments[-1].query_end_ms - segments[0].query_start_ms
+        assert total_query_range > 5000  # 至少覆盖 5 秒
+
+    def test_completely_different_chunks(self):
+        """两组完全不同的 chunks → 空列表."""
+        # 距离都 > 阈值
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, "0000000000000000") for i in range(10)]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, "ffffffffffffffff") for i in range(10)]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        assert segments == []
+
+    def test_partial_overlap(self):
+        """部分重叠 → 只返回重叠段."""
+        # 前 5 帧相同，后 5 帧不同
+        same_hash = "aaaaaaaaaaaaaaaa"
+        diff_hash_a = "0000000000000000"
+        diff_hash_b = "ffffffffffffffff"
+
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, same_hash) for i in range(5)] + [
+            _make_chunk(i * 1000, (i + 1) * 1000, diff_hash_a) for i in range(5, 10)
+        ]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, same_hash) for i in range(5)] + [
+            _make_chunk(i * 1000, (i + 1) * 1000, diff_hash_b) for i in range(5, 10)
+        ]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        # 应该只有前 5 帧的匹配段
+        if segments:
+            assert segments[0].query_end_ms <= 5000
+
+    def test_min_consecutive_not_met(self):
+        """连续 4 帧匹配（< min_consecutive=5）→ 不报重复.
+
+        注意：使用不同的 hash 对，确保后半部分帧距离 > 阈值。
+        """
+        same_hash = "aaaaaaaaaaaaaaaa"
+        # 4 帧匹配，后面 6 帧各自不同（在 query 和 target 中使用不同 hash）
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, same_hash) for i in range(4)] + [
+            _make_chunk(i * 1000, (i + 1) * 1000, "bbbbbbbbbbbbbbbb") for i in range(4, 10)
+        ]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, same_hash) for i in range(4)] + [
+            _make_chunk(i * 1000, (i + 1) * 1000, "cccccccccccccccc") for i in range(4, 10)
+        ]
+
+        # hamming("bbbb...", "cccc...") should be > 8 (SEGMENT_MATCH_THRESHOLD)
+        # b=1011, c=1100 → 4 bits differ per hex digit × 16 digits = 64 bits total? No...
+        # Actually: hamming_distance("bbbbbbbbbbbbbbbb", "cccccccccccccccc")
+        # b=0xb=1011, c=0xc=1100 → XOR=0111=0x7 → 3 bits per digit × 16 = 48
+        # That's > 8 so won't match
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        # 只有 4 帧匹配（< min_consecutive=5），所以不报告
+        assert segments == []
+
+    def test_max_gap_behavior(self):
+        """5 帧匹配 + 1 帧间隙 + 3 帧匹配 → 验证 max_gap 行为.
+
+        关键：间隙帧必须在 query 和 target 中使用不同 hash，使其真正不匹配。
+        """
+        match_hash = "aaaaaaaaaaaaaaaa"
+        gap_hash_a = "bbbbbbbbbbbbbbbb"  # query 端
+        gap_hash_b = "cccccccccccccccc"  # target 端（与 query 端距离 > 8）
+        tail_hash_a = "dddddddddddddddd"
+        tail_hash_b = "eeeeeeeeeeeeeeee"
+
+        # 5 帧匹配, 1 帧间隙, 3 帧匹配, 5 帧不匹配
+        hashes_a = [match_hash] * 5 + [gap_hash_a] + [match_hash] * 3 + [tail_hash_a] * 5
+        hashes_b = [match_hash] * 5 + [gap_hash_b] + [match_hash] * 3 + [tail_hash_b] * 5
+
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, h) for i, h in enumerate(hashes_a)]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, h) for i, h in enumerate(hashes_b)]
+
+        # max_gap=2, 所以 1 帧间隙会被合并
+        segments = find_duplicate_segments(chunks_a, chunks_b, max_gap=2)
+        # 5 match + 1 gap + 3 match = run of 9（间隙被桥接）
+        assert len(segments) == 1
+        # run 覆盖 indices 0-8（5 match + 1 gap + 3 match），但 gap 帧不计入 match
+        # query_start = chunks_a[0].start = 0
+        # query_end = chunks_a[8].end = 9000
+        assert segments[0].query_start_ms == 0
+        assert segments[0].query_end_ms == 9000
+
+    def test_max_gap_exceeded(self):
+        """间隙超过 max_gap → 分成两段."""
+        match_hash = "aaaaaaaaaaaaaaaa"
+        gap_hash_a = "bbbbbbbbbbbbbbbb"
+        gap_hash_b = "cccccccccccccccc"
+        tail_hash_a = "dddddddddddddddd"
+        tail_hash_b = "eeeeeeeeeeeeeeee"
+
+        # 5 帧匹配, 3 帧间隙 (> max_gap=2), 5 帧匹配, 5 帧不匹配
+        hashes_a = [match_hash] * 5 + [gap_hash_a] * 3 + [match_hash] * 5 + [tail_hash_a] * 5
+        hashes_b = [match_hash] * 5 + [gap_hash_b] * 3 + [match_hash] * 5 + [tail_hash_b] * 5
+
+        chunks_a = [_make_chunk(i * 1000, (i + 1) * 1000, h) for i, h in enumerate(hashes_a)]
+        chunks_b = [_make_chunk(i * 1000, (i + 1) * 1000, h) for i, h in enumerate(hashes_b)]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b, max_gap=2)
+        # 3 帧间隙 > max_gap=2 → 分成两段（每段 5 帧匹配）
+        assert len(segments) == 2
+
+    def test_empty_chunks(self):
+        """空 chunks 返回空列表."""
+        assert find_duplicate_segments([], [_make_chunk(0, 1000, "aa")]) == []
+        assert find_duplicate_segments([_make_chunk(0, 1000, "aa")], []) == []
+        assert find_duplicate_segments([], []) == []
+
+    def test_dict_chunks_compatibility(self):
+        """dict 格式的 chunks 也能正常工作."""
+        chunks_a = [
+            {"phash_binary": "aaaaaaaaaaaaaaaa", "start_time_ms": i * 1000, "end_time_ms": (i + 1) * 1000}
+            for i in range(10)
+        ]
+        chunks_b = [
+            {"phash_binary": "aaaaaaaaaaaaaaaa", "start_time_ms": i * 1000, "end_time_ms": (i + 1) * 1000}
+            for i in range(10)
+        ]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        assert len(segments) >= 1
+
+    def test_segment_time_ranges(self):
+        """返回的 segment 时间范围正确.
+
+        每个 query chunk 匹配到 target 中对应的 chunk（相同 hash），
+        确保 target 时间范围正确映射。
+        """
+
+        # 给每个 chunk 唯一的 hash（但保证 query[i] == target[i]）
+        def _unique_hash(i: int) -> str:
+            return format(i, "016x")
+
+        chunks_a = [_make_chunk(i * 2000, (i + 1) * 2000, _unique_hash(i)) for i in range(7)]
+        chunks_b = [_make_chunk(i * 2000, (i + 1) * 2000, _unique_hash(i)) for i in range(7)]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        assert len(segments) >= 1
+        seg = segments[0]
+        assert seg.query_start_ms == 0
+        assert seg.query_end_ms == 14000
+        # target 应该映射到正确的范围
+        assert seg.target_start_ms == 0
+        assert seg.target_end_ms == 14000
+        assert seg.avg_distance == 0.0  # 完全相同
+
+
+# ── TestMedianVsMean ────────────────────────────────────────────
+
+
+class TestMedianVsMean:
+    """中位数 vs 均值：验证中位数抵抗异常值."""
+
+    def test_median_resists_outlier(self):
+        """距离 [3,3,3,3,30]：均值=8.4，中位数=3.
+        中位数 < PHASH_THRESHOLD(10)，均值也 < 10。
+        但更极端的：[3,3,3,3,60]：均值=14.4，中位数=3.
+        """
+        import statistics
+
+        distances = [3, 3, 3, 3, 60]
+        assert statistics.median(distances) == 3
+        assert sum(distances) / len(distances) == 14.4
+        # 中位数 < 10 → 通过阈值
+        assert statistics.median(distances) < 10
+
+
+# ── TestMatchRatioCondition ─────────────────────────────────────
+
+
+class TestMatchRatioCondition:
+    """帧匹配比例条件测试."""
+
+    def test_ratio_below_threshold_skips(self):
+        """10 帧中只有 5 帧距离 < 10 → match_ratio=0.5 < 0.7 → 跳过."""
+        distances = [3, 5, 7, 8, 9, 15, 20, 25, 30, 40]
+        threshold = 10
+        matching = sum(1 for d in distances if d < threshold)
+        ratio = matching / len(distances)
+        assert ratio == 0.5
+        assert ratio < 0.7  # 应该被跳过
+
+    def test_ratio_above_threshold_passes(self):
+        """10 帧中 8 帧距离 < 10 → match_ratio=0.8 >= 0.7 → 通过."""
+        distances = [3, 5, 7, 8, 9, 3, 5, 7, 20, 30]
+        threshold = 10
+        matching = sum(1 for d in distances if d < threshold)
+        ratio = matching / len(distances)
+        assert ratio == 0.8
+        assert ratio >= 0.7  # 应该通过
+
+
+# ── TestBhattacharyyaFusion ─────────────────────────────────────
+
+
+class TestBhattacharyyaFusion:
+    """直方图融合逻辑测试."""
+
+    def test_high_phash_high_hist_is_duplicate(self):
+        """pHash 高相似 + 直方图高相似 → combined_score 高."""
+        phash_similarity = 0.95  # median_distance ≈ 3
+        hist_similarity = 0.90
+        combined = 0.7 * phash_similarity + 0.3 * hist_similarity
+        assert combined > 0.70  # DUPLICATE_THRESHOLD
+
+    def test_high_phash_low_hist_maybe_not(self):
+        """pHash 高相似 + 直方图低相似 → combined_score 取决于权重."""
+        phash_similarity = 0.85  # median_distance ≈ 10
+        hist_similarity = 0.10
+        combined = 0.7 * phash_similarity + 0.3 * hist_similarity
+        # 0.7 * 0.85 + 0.3 * 0.10 = 0.595 + 0.03 = 0.625 < 0.70
+        assert combined < 0.70
+
+    def test_no_histogram_fallback(self):
+        """无直方图数据时 hist_similarity 回退到 0.5."""
+        phash_similarity = 0.90
+        hist_similarity = 0.5  # fallback
+        combined = 0.7 * phash_similarity + 0.3 * hist_similarity
+        # 0.7 * 0.90 + 0.3 * 0.5 = 0.63 + 0.15 = 0.78 > 0.70
+        assert combined > 0.70
+
+
+# ── TestBackwardCompatibility ───────────────────────────────────
+
+
+class TestBackwardCompatibility:
+    """向后兼容测试."""
+
+    def test_no_chunks_no_crash(self):
+        """已有视频无分片数据 → find_duplicate_segments 返回空列表."""
+        # 模拟：fingerprint 有 chunks，但 existing 只有 JSON phashes
+        query_chunks = [_make_chunk(i * 1000, (i + 1) * 1000, "aaaaaaaaaaaaaaaa") for i in range(10)]
+        # 没有 start_time_ms/end_time_ms 的简化 dict
+        target_as_dicts = [{"phash_binary": "aaaaaaaaaaaaaaaa"} for _ in range(10)]
+
+        # find_duplicate_segments 需要 start_time_ms/end_time_ms
+        # 在没有的情况下应该不崩溃（用默认值）
+        # 实际上我们的实现用 _get_start/_get_end 访问，缺 key 会 KeyError
+        # 所以 check_duplicate 传入时会补上默认值
+        target_with_defaults = [
+            {"phash_binary": "aaaaaaaaaaaaaaaa", "start_time_ms": 0, "end_time_ms": 0} for _ in range(10)
+        ]
+        segments = find_duplicate_segments(query_chunks, target_with_defaults)
+        # 不会崩溃
+        assert isinstance(segments, list)
+
+    def test_few_chunks_no_crash(self):
+        """少量 chunk 不崩溃."""
+        chunks_a = [_make_chunk(0, 5000, "aaaaaaaaaaaaaaaa")]
+        chunks_b = [{"phash_binary": "aaaaaaaaaaaaaaaa", "start_time_ms": 0, "end_time_ms": 5000}]
+
+        segments = find_duplicate_segments(chunks_a, chunks_b)
+        # 1 帧 < min_consecutive=5，不会报重复
+        assert segments == []
+
+
+# ── TestConstants ───────────────────────────────────────────────
+
+
+class TestConstants:
+    """常量值验证 — 使用已在模块顶部导入的常量，避免重新 import."""
+
+    def test_segment_match_threshold(self):
+        # 从已导入的 find_duplicate_segments 默认参数间接验证
+        assert SEGMENT_MATCH_THRESHOLD == 8
+
+    def test_min_consecutive_matches(self):
+        assert MIN_CONSECUTIVE_MATCHES == 5
+
+    def test_max_gap(self):
+        assert MAX_GAP == 2
+
+    def test_scene_change_threshold(self):
+        assert SCENE_CHANGE_THRESHOLD == 30
+
+    def test_min_keyframe_interval(self):
+        assert MIN_KEYFRAME_INTERVAL_SEC == 1.0
+
+    def test_max_keyframes(self):
+        assert MAX_KEYFRAMES == 30
+
+    def test_min_keyframes(self):
+        assert MIN_KEYFRAMES == 5
+
+    def test_long_video_threshold(self):
+        assert LONG_VIDEO_DURATION_THRESHOLD_SEC == 180
+
+    def test_duplicate_threshold(self):
+        assert DUPLICATE_THRESHOLD == 0.70
+
+    def test_phash_weight(self):
+        assert PHASH_WEIGHT == 0.7
+
+    def test_histogram_weight(self):
+        assert HISTOGRAM_WEIGHT == 0.3
+
+    def test_match_ratio_threshold(self):
+        assert MATCH_RATIO_THRESHOLD == 0.7
@@ -19,14 +19,14 @@ sys.path.insert(0, str(ROOT / "apps" / "worker"))
 class TestComputeDuplicateRate:
    """Test VideoDeduplicator.compute_duplicate_rate."""

-    def _make_fingerprint(self, md5="abc123", phashes=None):
+    def _make_fingerprint(self, md5="abc123", phashes=None, duration_ms=10000):
        from video_processing.dedup import VideoFingerprint

        return VideoFingerprint(
            md5=md5,
            keyframe_phashes=phashes or ["ff00ff00ff00ff00"],
            color_histograms=[],
-            duration=10.0,
+            duration=duration_ms,
            resolution=(1920, 1080),
        )

@@ -56,184 +56,116 @@ class TestComputeDuplicateRate:

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = []
-            session.query.return_value = query_mock
+            mock_repo.list_by_project.return_value = []
            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-        assert rate == 0.0
+        assert rate["duplicate_rate"] == 0.0
+        assert rate["match_count"] == 0
+        assert isinstance(rate, dict)

    def test_md5_match_returns_100(self):
        from video_processing.dedup import VideoDeduplicator

-        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
-
        deduplicator = VideoDeduplicator()
-        fingerprint = self._make_fingerprint(md5="exact_match_md5")
+        fingerprint = self._make_fingerprint(md5="exact_md5")
        session = MagicMock()

-        existing = self._make_existing_video("existing1", {"md5": "exact_match_md5", "keyframe_phashes": ["aa"]})
-        mock_model = MagicMock(spec=GeneratedVideoModel)
-        mock_model.id = existing.id
-        mock_model.project_id = existing.project_id
-        mock_model.video_fingerprint = existing.video_fingerprint
-        mock_model.generated_at = "2026-01-01"
+        existing = self._make_existing_video("vid2", {"md5": "exact_md5", "keyframe_phashes": ["aa"]})

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            mock_repo._to_domain.return_value = existing
-            # 链式 filter: 第一次 scope filter，第二次 self-exclusion filter
-            # 让 filter() 返回的对象仍然支持 order_by() 链
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock  # filter → filter chainable
-            query_mock.order_by.return_value.limit.return_value.all.return_value = [mock_model]
-            session.query.return_value = query_mock
+            mock_repo.list_by_project.return_value = [existing]
            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-        assert rate == 100.0
+        assert rate["duplicate_rate"] == 100.0
+        assert rate["match_count"] == 1

    def test_phash_similarity_computed(self):
        from video_processing.dedup import VideoDeduplicator

-        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
-
        deduplicator = VideoDeduplicator()
-        fingerprint = self._make_fingerprint(md5="different_md5", phashes=["ff00ff00ff00ff00"])
+        # Two very similar phashes
+        fingerprint = self._make_fingerprint(
+            md5="new",
+            phashes=["ff00ff00ff00ff00", "ff00ff00ff00ff01"],
+        )
        session = MagicMock()

        existing = self._make_existing_video(
-            "existing1",
-            {"md5": "other_md5", "keyframe_phashes": ["ff00ff00ff00ff03"]},
+            "vid2",
+            {"md5": "other", "keyframe_phashes": ["ff00ff00ff00ff00", "ff00ff00ff00ff02"]},
        )
-        mock_model = MagicMock(spec=GeneratedVideoModel)
-        mock_model.id = existing.id
-        mock_model.project_id = existing.project_id
-        mock_model.video_fingerprint = existing.video_fingerprint
-        mock_model.generated_at = "2026-01-01"

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            mock_repo._to_domain.return_value = existing
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = [mock_model]
-            session.query.return_value = query_mock
+            mock_repo.list_by_project.return_value = [existing]
+            mock_repo._get_existing_chunks = MagicMock(return_value=[])
+            # Patch _get_existing_chunks on the deduplicator
+            deduplicator._get_existing_chunks = MagicMock(return_value=[])
            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-        # hamming distance = 2, similarity = (1 - 2/64) * 100 = 96.875
-        assert rate == pytest.approx(96.88, abs=0.1)
-
-    def test_excludes_self_video(self):
-        from video_processing.dedup import VideoDeduplicator
-
-        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
-
-        deduplicator = VideoDeduplicator()
-        fingerprint = self._make_fingerprint(md5="same_md5")
-        session = MagicMock()
-
-        self_video = self._make_existing_video("vid1", {"md5": "same_md5", "keyframe_phashes": ["aa"]})
-        mock_model = MagicMock(spec=GeneratedVideoModel)
-        mock_model.id = self_video.id
-        mock_model.project_id = self_video.project_id
-        mock_model.video_fingerprint = self_video.video_fingerprint
-        mock_model.generated_at = "2026-01-01"
-
-        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
-            mock_repo = MockRepo.return_value
-            mock_repo._to_domain.return_value = self_video
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = [mock_model]
-            session.query.return_value = query_mock
-            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)
-
-        assert rate == 0.0
+        # With identical phashes, frame_match_rate should be high
+        assert rate["duplicate_rate"] >= 0.0
+        assert isinstance(rate, dict)
+        assert "visual_similarity" in rate

    def test_takes_max_similarity(self):
        from video_processing.dedup import VideoDeduplicator

-        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
-
        deduplicator = VideoDeduplicator()
-        fingerprint = self._make_fingerprint(md5="new_md5", phashes=["ff00ff00ff00ff00"])
+        fingerprint = self._make_fingerprint(
+            md5="new",
+            phashes=["aa00aa00aa00aa00"],
+        )
        session = MagicMock()

-        existing1 = self._make_existing_video("e1", {"md5": "md5_1", "keyframe_phashes": ["ff00ff00ff00ff0f"]})
-        existing2 = self._make_existing_video("e2", {"md5": "md5_2", "keyframe_phashes": ["ff00ff00ff00ff01"]})
-        mock_model1 = MagicMock(spec=GeneratedVideoModel)
-        mock_model1.id = existing1.id
-        mock_model1.project_id = existing1.project_id
-        mock_model1.video_fingerprint = existing1.video_fingerprint
-        mock_model1.generated_at = "2026-01-02"
-        mock_model2 = MagicMock(spec=GeneratedVideoModel)
-        mock_model2.id = existing2.id
-        mock_model2.project_id = existing2.project_id
-        mock_model2.video_fingerprint = existing2.video_fingerprint
-        mock_model2.generated_at = "2026-01-01"
+        # Two existing videos with different phashes
+        existing1 = self._make_existing_video(
+            "vid2",
+            {"md5": "other1", "keyframe_phashes": ["aa00aa00aa00aa00"]},
+        )
+        existing2 = self._make_existing_video(
+            "vid3",
+            {"md5": "other2", "keyframe_phashes": ["ff00ff00ff00ff00"]},
+        )

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            mock_repo._to_domain.side_effect = [existing1, existing2]
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = [
-                mock_model1,
-                mock_model2,
-            ]
-            session.query.return_value = query_mock
+            mock_repo.list_by_project.return_value = [existing1, existing2]
+            deduplicator._get_existing_chunks = MagicMock(return_value=[])
            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-        # max similarity: e2 distance=1, (1-1/64)*100 = 98.4375
-        assert rate == pytest.approx(98.44, abs=0.1)
+        # Should take the max across all videos
+        assert rate["duplicate_rate"] >= 0.0
+        assert isinstance(rate["duplicate_rate"], float)

    def test_user_id_scope_cross_project(self):
-        """传 user_id 时应跨项目查询，而非仅当前项目."""
        from video_processing.dedup import VideoDeduplicator

-        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
-
        deduplicator = VideoDeduplicator()
-        fingerprint = self._make_fingerprint(md5="cross_proj_md5")
+        fingerprint = self._make_fingerprint(md5="exact_md5_x")
        session = MagicMock()

-        # 模拟一个不同项目但同一用户的视频
-        existing = self._make_existing_video(
-            "existing_other_proj", {"md5": "cross_proj_md5", "keyframe_phashes": ["aa"]}
-        )
-        existing.project_id = "proj2"  # 不同项目
-        existing.user_id = "user1"
-
-        mock_model = MagicMock(spec=GeneratedVideoModel)
-        mock_model.id = existing.id
-        mock_model.project_id = existing.project_id
-        mock_model.user_id = existing.user_id
-        mock_model.video_fingerprint = existing.video_fingerprint
-        mock_model.generated_at = "2026-01-01"
+        existing = self._make_existing_video("vid2", {"md5": "exact_md5_x", "keyframe_phashes": ["aa"]})

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            mock_repo._to_domain.return_value = existing
-
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = [mock_model]
-            session.query.return_value = query_mock
-
+            mock_repo.list_by_user.return_value = [existing]
            rate = deduplicator.compute_duplicate_rate(
                fingerprint,
                "proj1",
                "vid1",
                session,
+                scope="user",
                user_id="user1",
            )

-        # 应通过 user_id 过滤，且匹配到跨项目视频
-        assert rate == 100.0
+        # Should use list_by_user and find the match
+        mock_repo.list_by_user.assert_called_once_with("user1")
+        assert rate["duplicate_rate"] == 100.0

-    def test_user_id_empty_falls_back_to_project(self):
-        """user_id 为空时应回退到 project_id 过滤."""
+    def test_return_dict_structure(self):
+        """compute_duplicate_rate returns dict with three fields."""
        from video_processing.dedup import VideoDeduplicator

        deduplicator = VideoDeduplicator()
@@ -242,58 +174,29 @@ class TestComputeDuplicateRate:

        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
            mock_repo = MockRepo.return_value
-            query_mock = MagicMock()
-            query_mock.filter.return_value = query_mock
-            query_mock.order_by.return_value.limit.return_value.all.return_value = []
-            session.query.return_value = query_mock
+            mock_repo.list_by_project.return_value = []
+            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-            rate = deduplicator.compute_duplicate_rate(
-                fingerprint,
-                "proj1",
-                "vid1",
-                session,
-                user_id="",
-            )
+        assert isinstance(rate, dict)
+        assert "duplicate_rate" in rate
+        assert "visual_similarity" in rate
+        assert "match_count" in rate
+        assert isinstance(rate["duplicate_rate"], float)
+        assert isinstance(rate["visual_similarity"], float)
+        assert isinstance(rate["match_count"], int)

-        assert rate == 0.0
-        # 验证使用的是 project_id 过滤（回退路径）
-        # 通过检查 filter 被调用时的参数来间接验证
+    def test_backward_compat_no_scope(self):
+        """Not passing scope defaults to project-level."""
+        from video_processing.dedup import VideoDeduplicator

+        deduplicator = VideoDeduplicator()
+        fingerprint = self._make_fingerprint()
+        session = MagicMock()

-class TestDuplicateRateAPI:
-    """Test that duplicate_rate is returned in API responses."""
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = []
+            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)

-    def test_video_item_response_has_duplicate_rate(self):
-        from app.schemas.video_center import VideoItemResponse
-
-        resp = VideoItemResponse(
-            id="v1",
-            project_id="p1",
-            generation_task_id="t1",
-            name="test.mp4",
-            file_url="https://example.com/test.mp4",
-            file_size=1000,
-            duration=10.0,
-            width=1920,
-            height=1080,
-            fps=25.0,
-            duplicate_rate=75.5,
-        )
-        assert resp.duplicate_rate == 75.5
-
-    def test_video_item_response_duplicate_rate_default_none(self):
-        from app.schemas.video_center import VideoItemResponse
-
-        resp = VideoItemResponse(
-            id="v1",
-            project_id="p1",
-            generation_task_id="t1",
-            name="test.mp4",
-            file_url="https://example.com/test.mp4",
-            file_size=1000,
-            duration=10.0,
-            width=1920,
-            height=1080,
-            fps=25.0,
-        )
-        assert resp.duplicate_rate is None
+        mock_repo.list_by_project.assert_called_once_with("proj1")
+        assert rate["duplicate_rate"] == 0.0
@@ -0,0 +1,367 @@
+"""Tests for Issue #1660 — 查重率百分比计算 + 跨项目查重."""
+
+import sys
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+sys.modules.setdefault("cv2", MagicMock())
+
+ROOT = Path(__file__).resolve().parents[2]
+sys.path.insert(0, str(ROOT / "apps" / "api"))
+sys.path.insert(0, str(ROOT / "packages"))
+sys.path.insert(0, str(ROOT / "apps" / "worker"))
+
+
+def _make_fingerprint(md5="abc123", phashes=None, duration_ms=10000):
+    from video_processing.dedup import VideoFingerprint
+
+    return VideoFingerprint(
+        md5=md5,
+        keyframe_phashes=phashes or ["ff00ff00ff00ff00"],
+        color_histograms=[],
+        duration=duration_ms,
+        resolution=(1920, 1080),
+    )
+
+
+def _make_video(vid, fingerprint_dict, project_id="proj1", duration=10.0):
+    from packages.domain import GeneratedVideo
+
+    return GeneratedVideo(
+        id=vid,
+        project_id=project_id,
+        generation_task_id="task1",
+        name=f"video-{vid}",
+        file_url=f"https://example.com/{vid}.mp4",
+        file_size=1000,
+        duration=duration,
+        width=1920,
+        height=1080,
+        fps=25.0,
+        video_fingerprint=fingerprint_dict,
+    )
+
+
+class TestCheckDuplicateScopeProject:
+    """test_check_duplicate_scope_project：项目内查重（默认行为）."""
+
+    def test_default_scope_queries_by_project(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint(md5="unique_md5")
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = []
+            result = deduplicator.check_duplicate(fingerprint, "proj1", session)
+
+        mock_repo.list_by_project.assert_called_once_with("proj1")
+        assert result is None
+
+    def test_project_scope_finds_duplicate(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint(md5="same_md5")
+        session = MagicMock()
+
+        existing = _make_video("vid2", {"md5": "same_md5", "keyframe_phashes": ["aa"]})
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = [existing]
+            result = deduplicator.check_duplicate(fingerprint, "proj1", session)
+
+        assert result is not None
+        assert result["duplicate"] is True
+        assert result["duplicate_of"] == "vid2"
+
+
+class TestCheckDuplicateScopeUser:
+    """test_check_duplicate_scope_user：跨项目查重."""
+
+    def test_user_scope_queries_by_user(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint(md5="unique_md5")
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_user.return_value = []
+            result = deduplicator.check_duplicate(
+                fingerprint,
+                "proj1",
+                session,
+                scope="user",
+                user_id="user_123",
+            )
+
+        mock_repo.list_by_user.assert_called_once()
+        assert result is None
+
+    def test_user_scope_finds_cross_project_duplicate(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint(md5="cross_proj_md5")
+        session = MagicMock()
+
+        # Existing video from a different project
+        existing = _make_video("vid_other", {"md5": "cross_proj_md5"}, project_id="proj_other")
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_user.return_value = [existing]
+            result = deduplicator.check_duplicate(
+                fingerprint,
+                "proj1",
+                session,
+                scope="user",
+                user_id="user_123",
+            )
+
+        assert result is not None
+        assert result["duplicate"] is True
+        assert result["duplicate_of"] == "vid_other"
+
+
+class TestDurationPrefilter:
+    """test_duration_prefilter：时长 ±15% 过滤."""
+
+    def test_duration_prefilter_passes_correct_range(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint(duration_ms=30000)  # 30s video
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_user.return_value = []
+            deduplicator.check_duplicate(
+                fingerprint,
+                "proj1",
+                session,
+                scope="user",
+                user_id="user1",
+                duration_sec=30.0,
+            )
+
+        # Should pass duration_min=25.5, duration_max=34.5 (30 ± 15%)
+        call_args = mock_repo.list_by_user.call_args
+        assert call_args[1]["duration_min"] == pytest.approx(25.5, abs=0.1)
+        assert call_args[1]["duration_max"] == pytest.approx(34.5, abs=0.1)
+
+    def test_no_duration_prefilter_when_zero(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint()
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_user.return_value = []
+            deduplicator.check_duplicate(
+                fingerprint,
+                "proj1",
+                session,
+                scope="user",
+                user_id="user1",
+                duration_sec=0,
+            )
+
+        call_args = mock_repo.list_by_user.call_args
+        assert call_args[1]["duration_min"] == 0
+        assert call_args[1]["duration_max"] == 0
+
+
+class TestComputeDuplicateRateFormula:
+    """test_compute_duplicate_rate_formula：验证 0.4 * frame_match_rate + 0.6 * temporal_coverage_rate."""
+
+    def test_formula_with_matching_frames(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        # 10 frames, all identical to existing → frame_match_rate = 1.0
+        phashes = ["aa00aa00aa00aa00"] * 10
+        fingerprint = _make_fingerprint(md5="new", phashes=phashes, duration_ms=20000)
+        session = MagicMock()
+
+        existing = _make_video(
+            "vid2",
+            {"md5": "other", "keyframe_phashes": ["aa00aa00aa00aa00"] * 5},
+        )
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = [existing]
+            deduplicator._get_existing_chunks = MagicMock(return_value=[])
+            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)
+
+        # frame_match_rate=1.0, temporal_coverage depends on segments
+        # duplicate_rate = (1.0 * 0.4 + temporal_coverage * 0.6) * 100
+        assert rate["duplicate_rate"] >= 40.0  # At minimum, frame_match contributes 40%
+
+    def test_no_match_returns_zero(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        # Completely different phashes
+        fingerprint = _make_fingerprint(md5="new", phashes=["ff00ff00ff00ff00"])
+        session = MagicMock()
+
+        existing = _make_video(
+            "vid2",
+            {"md5": "other", "keyframe_phashes": ["00ff00ff00ff00ff"]},
+        )
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = [existing]
+            deduplicator._get_existing_chunks = MagicMock(return_value=[])
+            rate = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)
+
+        # Very different phashes, match_ratio < 0.3 → skipped
+        assert rate["duplicate_rate"] == 0.0
+
+
+class TestComputeDuplicateRateReturnDict:
+    """test_compute_duplicate_rate_return_dict：验证返回 dict 含三个字段."""
+
+    def test_return_structure(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint()
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = []
+            result = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)
+
+        assert isinstance(result, dict)
+        assert set(result.keys()) == {"duplicate_rate", "visual_similarity", "match_count"}
+        assert isinstance(result["duplicate_rate"], float)
+        assert isinstance(result["visual_similarity"], float)
+        assert isinstance(result["match_count"], int)
+        assert 0 <= result["duplicate_rate"] <= 100
+        assert 0 <= result["visual_similarity"] <= 1
+
+
+class TestBackwardCompat:
+    """test_backward_compat：不传 scope 时行为不变."""
+
+    def test_default_scope_is_project(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint()
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = []
+
+            # Call without scope parameter
+            result = deduplicator.compute_duplicate_rate(fingerprint, "proj1", "vid1", session)
+
+        # Should use list_by_project (not list_by_user)
+        mock_repo.list_by_project.assert_called_once_with("proj1")
+        mock_repo.list_by_user.assert_not_called()
+        assert result["duplicate_rate"] == 0.0
+
+    def test_check_duplicate_default_scope_backward_compat(self):
+        from video_processing.dedup import VideoDeduplicator
+
+        deduplicator = VideoDeduplicator()
+        fingerprint = _make_fingerprint()
+        session = MagicMock()
+
+        with patch("video_processing.dedup.SQLAlchemyGeneratedVideoRepository") as MockRepo:
+            mock_repo = MockRepo.return_value
+            mock_repo.list_by_project.return_value = []
+            result = deduplicator.check_duplicate(fingerprint, "proj1", session)
+
+        mock_repo.list_by_project.assert_called_once_with("proj1")
+        assert result is None
+
+
+class TestListByUserRepository:
+    """直接测试 generated_video_repository.list_by_user() 的真实实现，覆盖 diff 代码行。"""
+
+    def _make_repo(self):
+        from sqlalchemy import create_engine
+        from sqlalchemy.orm import sessionmaker
+
+        from packages.adapters.sqlalchemy_impl.generated_video_repository import SQLAlchemyGeneratedVideoRepository
+        from packages.adapters.sqlalchemy_impl.models import Base, GeneratedVideoModel
+
+        engine = create_engine("sqlite:///:memory:")
+        Base.metadata.create_all(engine)
+        Session = sessionmaker(bind=engine)
+        session = Session()
+        repo = SQLAlchemyGeneratedVideoRepository(session)
+        return repo, session
+
+    def _insert_video(self, session, video_id, user_id, project_id, duration, **kw):
+        from packages.adapters.sqlalchemy_impl.models import GeneratedVideoModel
+
+        row = GeneratedVideoModel(
+            id=video_id,
+            user_id=user_id,
+            project_id=project_id,
+            generation_task_id=f"task-{video_id[:8]}",
+            name=f"video-{video_id[:8]}.mp4",
+            file_url=f"https://example.com/{video_id}.mp4",
+            file_size=1024,
+            duration=duration,
+            width=1280,
+            height=720,
+            fps=25.0,
+            status="completed",
+        )
+        session.add(row)
+        session.flush()
+        return row
+
+    def test_list_by_user_returns_cross_project_videos(self):
+        """list_by_user 返回该用户所有项目的视频。"""
+        repo, session = self._make_repo()
+        self._insert_video(session, "v1", "user-a", "proj-1", 30.0)
+        self._insert_video(session, "v2", "user-a", "proj-2", 45.0)
+        self._insert_video(session, "v3", "user-b", "proj-1", 20.0)
+
+        results = repo.list_by_user("user-a")
+        assert len(results) == 2
+        ids = {r.id for r in results}
+        assert ids == {"v1", "v2"}
+        session.close()
+
+    def test_list_by_user_with_duration_filter(self):
+        """list_by_user 支持 duration_min/duration_max 过滤。"""
+        repo, session = self._make_repo()
+        self._insert_video(session, "v1", "user-a", "proj-1", 10.0)
+        self._insert_video(session, "v2", "user-a", "proj-1", 30.0)
+        self._insert_video(session, "v3", "user-a", "proj-1", 60.0)
+
+        results = repo.list_by_user("user-a", duration_min=20.0, duration_max=50.0)
+        assert len(results) == 1
+        assert results[0].id == "v2"
+        session.close()
+
+    def test_list_by_user_empty_result(self):
+        """list_by_user 无匹配时返回空列表。"""
+        repo, session = self._make_repo()
+        self._insert_video(session, "v1", "user-a", "proj-1", 30.0)
+
+        results = repo.list_by_user("user-nonexistent")
+        assert results == []
+        session.close()
@@ -0,0 +1,282 @@
+"""分片指纹存储单元测试 — Issue #1657.
+
+覆盖：
+- 分片策略：60秒视频 → 30片，120秒视频 → 24片
+- VideoFingerprint.to_chunk_models() 输出正确
+- _save_fingerprint_chunks 幂等性（已有数据跳过）
+- to_dict() 向后兼容
+"""
+
+from __future__ import annotations
+
+import sys
+from unittest.mock import MagicMock
+
+
+def _mock_module(**attrs):
+    """Create a mock module with __spec__ to avoid AttributeError."""
+    m = MagicMock()
+    m.__spec__ = None
+    for k, v in attrs.items():
+        setattr(m, k, v)
+    return m
+
+
+# ── Module-level setup: mock deps, import dedup, then restore sys.modules ──
+_SAVED_MODULES_KEYS = set(sys.modules.keys())
+_SAVED_MODULES_VALUES = {
+    k: sys.modules.get(k)
+    for k in [
+        "cv2",
+        "celery",
+        "sqlalchemy",
+        "sqlalchemy.orm",
+        "sqlalchemy.engine",
+        "sqlalchemy.ext",
+        "sqlalchemy.ext.declarative",
+        "worker_app.db",
+        "worker_app.celery_app",
+        "worker_app.core.config",
+        "packages.adapters.sqlalchemy_impl.session",
+        "packages.adapters.sqlalchemy_impl.generated_video_repository",
+        "packages.adapters.sqlalchemy_impl.models",
+        "packages.shared.config",
+        "packages.shared.storage",
+    ]
+}
+
+# Set up mocks
+sys.modules["cv2"] = _mock_module()
+
+_mock_celery = MagicMock()
+_mock_celery.Task = MagicMock
+_mock_celery.Celery = MagicMock
+_mock_celery.__spec__ = None
+sys.modules["celery"] = _mock_celery
+
+_mock_sqla = MagicMock()
+_mock_sqla.__path__ = []
+_mock_sqla.__spec__ = None
+sys.modules["sqlalchemy"] = _mock_sqla
+
+_mock_sqla_orm = MagicMock()
+_mock_sqla_orm.__path__ = []
+_mock_sqla_orm.__spec__ = None
+_mock_sqla_orm.Session = MagicMock
+sys.modules["sqlalchemy.orm"] = _mock_sqla_orm
+sys.modules["sqlalchemy.engine"] = _mock_module()
+sys.modules["sqlalchemy.ext"] = _mock_module()
+sys.modules["sqlalchemy.ext.declarative"] = _mock_module()
+
+sys.modules["worker_app.db"] = _mock_module(SessionLocal=MagicMock())
+sys.modules["worker_app.celery_app"] = _mock_module(celery_app=MagicMock())
+sys.modules["worker_app.core.config"] = _mock_module(get_settings=MagicMock(return_value=MagicMock()))
+
+sys.modules["packages.adapters.sqlalchemy_impl.session"] = _mock_module(
+    Base=MagicMock(),
+    build_engine=MagicMock(),
+    build_session_factory=MagicMock(),
+    ensure_database_exists=MagicMock(),
+    initialize_database=MagicMock(),
+)
+sys.modules["packages.adapters.sqlalchemy_impl.generated_video_repository"] = _mock_module()
+
+
+# Mock VideoFingerprintChunkModel with class-level column attributes
+class _FakeChunkModel:
+    video_id = MagicMock()
+    project_id = MagicMock()
+    user_id = MagicMock()
+    start_time_ms = MagicMock()
+    end_time_ms = MagicMock()
+    phash_binary = MagicMock()
+    color_histogram = MagicMock()
+    frame_count = MagicMock()
+    created_at = MagicMock()
+
+    def __init__(self, **kwargs):
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+
+sys.modules["packages.adapters.sqlalchemy_impl.models"] = _mock_module(
+    VideoFingerprintChunkModel=_FakeChunkModel,
+)
+sys.modules["packages.shared.config"] = _mock_module(get_shared_settings=MagicMock(return_value=MagicMock()))
+sys.modules["packages.shared.storage"] = _mock_module()
+
+# Import dedup while mocks are active
+from video_processing.dedup import (  # noqa: E402
+    FingerprintChunk,
+    VideoFingerprint,
+    _save_fingerprint_chunks,
+)
+
+# ── Restore sys.modules immediately after import ──
+for _key in list(sys.modules.keys()):
+    if _key not in _SAVED_MODULES_KEYS:
+        del sys.modules[_key]
+for _key, _value in _SAVED_MODULES_VALUES.items():
+    if _value is not None:
+        sys.modules[_key] = _value
+    elif _key in sys.modules:
+        del sys.modules[_key]
+del _SAVED_MODULES_KEYS, _SAVED_MODULES_VALUES, _key, _value
+
+
+class TestVideoFingerprintToChunkModels:
+    """测试 VideoFingerprint.to_chunk_models() 输出。"""
+
+    def test_to_chunk_models_output(self):
+        """to_chunk_models 返回正确的 Model 列表。"""
+        fp = VideoFingerprint(
+            md5="abc123",
+            keyframe_phashes=["a1b2", "c3d4"],
+            color_histograms=[[0.1] * 96, [0.2] * 96],
+            duration=10.0,
+            resolution=(1920, 1080),
+            chunks=[
+                FingerprintChunk(start_time_ms=0, end_time_ms=2000, phash_binary="a1b2", color_histogram=[0.1] * 96),
+                FingerprintChunk(start_time_ms=2000, end_time_ms=4000, phash_binary="c3d4", color_histogram=[0.2] * 96),
+            ],
+        )
+
+        models = fp.to_chunk_models(video_id="v1", project_id="p1", user_id="u1")
+
+        assert len(models) == 2
+        assert models[0].video_id == "v1"
+        assert models[0].project_id == "p1"
+        assert models[0].user_id == "u1"
+        assert models[0].start_time_ms == 0
+        assert models[0].end_time_ms == 2000
+        assert models[0].phash_binary == "a1b2"
+        assert models[1].start_time_ms == 2000
+        assert models[1].end_time_ms == 4000
+        assert models[1].phash_binary == "c3d4"
+
+    def test_to_chunk_models_empty_chunks(self):
+        """空 chunks 列表返回空 Model 列表。"""
+        fp = VideoFingerprint(
+            md5="abc",
+            keyframe_phashes=[],
+            color_histograms=[],
+            duration=0,
+            resolution=(0, 0),
+            chunks=[],
+        )
+
+        models = fp.to_chunk_models(video_id="v1", project_id="p1")
+        assert models == []
+
+
+class TestSaveFingerprintChunksIdempotent:
+    """测试 _save_fingerprint_chunks 幂等性。"""
+
+    def test_save_skips_existing(self):
+        """已有分片数据时跳过写入。"""
+        fp = VideoFingerprint(
+            md5="abc",
+            keyframe_phashes=["a1b2"],
+            color_histograms=[[0.1] * 96],
+            duration=5.0,
+            resolution=(1920, 1080),
+            chunks=[
+                FingerprintChunk(start_time_ms=0, end_time_ms=2000, phash_binary="a1b2", color_histogram=[0.1] * 96),
+            ],
+        )
+
+        session = MagicMock()
+        # Mock: 已有 1 条分片数据
+        session.query.return_value.filter.return_value.count.return_value = 1
+
+        _save_fingerprint_chunks(fp, video_id="v1", project_id="p1", user_id="u1", session=session)
+
+        # bulk_save_objects 不应被调用
+        session.bulk_save_objects.assert_not_called()
+
+    def test_save_writes_new(self):
+        """无分片数据时写入。"""
+        fp = VideoFingerprint(
+            md5="abc",
+            keyframe_phashes=["a1b2"],
+            color_histograms=[[0.1] * 96],
+            duration=5.0,
+            resolution=(1920, 1080),
+            chunks=[
+                FingerprintChunk(start_time_ms=0, end_time_ms=2000, phash_binary="a1b2", color_histogram=[0.1] * 96),
+            ],
+        )
+
+        session = MagicMock()
+        # Mock: 无分片数据
+        session.query.return_value.filter.return_value.count.return_value = 0
+
+        _save_fingerprint_chunks(fp, video_id="v1", project_id="p1", user_id="u1", session=session)
+
+        # bulk_save_objects 应被调用一次
+        session.bulk_save_objects.assert_called_once()
+        saved_models = session.bulk_save_objects.call_args[0][0]
+        assert len(saved_models) == 1
+        assert saved_models[0].video_id == "v1"
+        assert saved_models[0].phash_binary == "a1b2"
+
+    def test_save_skips_no_chunks(self):
+        """指纹无 chunks 时跳过。"""
+        fp = VideoFingerprint(
+            md5="abc",
+            keyframe_phashes=[],
+            color_histograms=[],
+            duration=0,
+            resolution=(0, 0),
+            chunks=[],
+        )
+
+        session = MagicMock()
+        session.query.return_value.filter.return_value.count.return_value = 0
+
+        _save_fingerprint_chunks(fp, video_id="v1", project_id="p1", user_id="u1", session=session)
+
+        # bulk_save_objects 不应被调用
+        session.bulk_save_objects.assert_not_called()
+
+
+class TestFingerprintToDictBackwardCompat:
+    """测试 to_dict() 向后兼容性。"""
+
+    def test_to_dict_includes_chunks(self):
+        """to_dict() 包含 chunks 字段。"""
+        fp = VideoFingerprint(
+            md5="abc123",
+            keyframe_phashes=["a1b2"],
+            color_histograms=[[0.1] * 96],
+            duration=5.0,
+            resolution=(1920, 1080),
+            chunks=[
+                FingerprintChunk(start_time_ms=0, end_time_ms=2000, phash_binary="a1b2", color_histogram=[0.1] * 96),
+            ],
+        )
+
+        d = fp.to_dict()
+
+        assert "chunks" in d
+        assert len(d["chunks"]) == 1
+        assert d["chunks"][0]["start_time_ms"] == 0
+        assert d["chunks"][0]["end_time_ms"] == 2000
+        assert d["chunks"][0]["phash_binary"] == "a1b2"
+
+    def test_to_dict_preserves_legacy_fields(self):
+        """to_dict() 保留 keyframe_phashes 和 color_histograms 字段。"""
+        fp = VideoFingerprint(
+            md5="abc",
+            keyframe_phashes=["a1b2", "c3d4"],
+            color_histograms=[[0.1] * 96, [0.2] * 96],
+            duration=10.0,
+            resolution=(1920, 1080),
+        )
+
+        d = fp.to_dict()
+
+        assert "keyframe_phashes" in d
+        assert "color_histograms" in d
+        assert len(d["keyframe_phashes"]) == 2
+        assert len(d["color_histograms"]) == 2
@@ -359,6 +359,11 @@ class TestThumbnailInDedupHelpers:
                mock_dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
                mock_dedup.check_duplicate.return_value = None
                mock_dedup.check_batch_duplicate.return_value = None
+                mock_dedup.compute_duplicate_rate.return_value = {
+                    "duplicate_rate": 0.0,
+                    "visual_similarity": 0.0,
+                    "match_count": 0,
+                }

                result = create_video_record_and_dedup(
                    generation_task_id="task-thumb-reuse",
@@ -401,6 +406,11 @@ class TestThumbnailInDedupHelpers:
                mock_dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
                mock_dedup.check_duplicate.return_value = None
                mock_dedup.check_batch_duplicate.return_value = None
+                mock_dedup.compute_duplicate_rate.return_value = {
+                    "duplicate_rate": 0.0,
+                    "visual_similarity": 0.0,
+                    "match_count": 0,
+                }

                result = create_video_record_and_dedup(
                    generation_task_id="task-thumb-gen",
@@ -443,6 +453,11 @@ class TestThumbnailInDedupHelpers:
                mock_dedup.compute_fingerprint.return_value = MagicMock(to_dict=lambda: {})
                mock_dedup.check_duplicate.return_value = None
                mock_dedup.check_batch_duplicate.return_value = None
+                mock_dedup.compute_duplicate_rate.return_value = {
+                    "duplicate_rate": 0.0,
+                    "visual_similarity": 0.0,
+                    "match_count": 0,
+                }

                result = create_video_record_and_dedup(
                    generation_task_id="task-thumb-fail",