apps/api/app/api/routes/ai_avatar_render.py

@@ -198,12 +198,21 @@ def generate_avatar_smart_cover(
     if not video_url.startswith(("http://", "https://")):
         raise HTTPException(status_code=400, detail="video_url 必须是合法的 HTTP/HTTPS URL")
 
-    cover_url = generate_smart_cover(video_url, max_frames=body.max_frames)
+    try:
+        cover_url = generate_smart_cover(video_url, max_frames=body.max_frames)
+    except Exception as exc:
+        logger.error(
+            "智能封面生成异常: user=%s video_url=%s err=%s",
+            current_user.user.id, video_url[:80], exc,
+            exc_info=True,
+        )
+        cover_url = ""
+
     if not cover_url:
         return SmartCoverResponse(
             cover_url="",
             status="fallback_failed",
             message="智能抽帧失败（MediaKit 不可用或抽帧异常），请稍后重试",
         )
-    logger.info("智能封面生成成功: user=%s", current_user.user.id)
+    logger.info("智能封面生成成功: user=%s cover_url=%s", current_user.user.id, cover_url[:120])
     return SmartCoverResponse(cover_url=cover_url, status="completed")

apps/api/app/services/ai_avatar_cover_service.py

@@ -15,9 +15,49 @@ import tempfile
 import uuid
 from pathlib import Path
 from typing import Optional
+from urllib.parse import urlparse
 
 logger = logging.getLogger(__name__)
 
+# MediaKit 抽帧轮询参数（与 MediaKit API timeout=60s 对齐）
+COVER_POLL_INTERVAL = 3.0
+COVER_MAX_POLL_ATTEMPTS = 20  # 最多等 60 秒
+
+# 帧图片下载超时（秒）
+FRAME_DOWNLOAD_TIMEOUT = 20
+# 最佳帧下载超时（用于 persist）
+BEST_FRAME_DOWNLOAD_TIMEOUT = 30
+
+# 自家 OSS 私有桶 URL 重签有效期（供 MediaKit GPU worker 拉取）
+MEDIAKIT_URL_TTL_SECONDS = 7 * 24 * 3600
+
+
+def _sign_video_url_for_mediakit(video_url: str) -> str:
+    """如果 video_url 是自家 OSS 私有桶 URL，重新签名为长有效期预签名 URL。
+
+    MediaKit GPU worker 需要能公网访问 video_url，裸 public_url 在私有桶下会 403。
+    """
+    if not video_url:
+        return video_url
+    try:
+        from packages.shared.storage import get_shared_storage_service
+
+        storage = get_shared_storage_service()
+        public_base = getattr(storage, "public_url", "")
+        if not isinstance(public_base, str) or not public_base:
+            return video_url
+        own_host = urlparse(public_base).netloc.lower()
+        url_host = urlparse(video_url).netloc.lower()
+        if own_host and url_host == own_host:
+            # 是自家 OSS URL，重签 7 天有效期供 MediaKit 拉取
+            signed = storage.get_download_url(video_url, expires_seconds=MEDIAKIT_URL_TTL_SECONDS)
+            if signed:
+                logger.info("[数字人封面] video_url 已重签（自家 OSS 私有桶）")
+                return signed
+    except Exception:
+        logger.warning("[数字人封面] video_url 重签失败，使用原始 URL", exc_info=True)
+    return video_url
+
 
 def select_best_cover_frame(video_url: str, *, max_frames: int = 5) -> str:
     """从视频抽取多帧并评分选最佳帧，返回最佳帧的临时 URL.
@@ -31,6 +71,10 @@ def select_best_cover_frame(video_url: str, *, max_frames: int = 5) -> str:
     """
     if not video_url:
         return ""
+
+    # 确保 MediaKit 能访问 video_url（自家 OSS 私有桶需重签）
+    video_url = _sign_video_url_for_mediakit(video_url)
+
     try:
         from packages.shared.cover_frame_scorer import score_frames
         from packages.shared.mediakit_client import get_mediakit_client
@@ -40,13 +84,21 @@ def select_best_cover_frame(video_url: str, *, max_frames: int = 5) -> str:
             logger.warning("[数字人封面] MediaKit 未配置，无法智能抽帧")
             return ""
 
+        logger.info(
+            "[数字人封面] 开始抽帧: video_url=%s max_frames=%d poll_interval=%.1f max_poll=%d",
+            video_url[:80],
+            max_frames,
+            COVER_POLL_INTERVAL,
+            COVER_MAX_POLL_ATTEMPTS,
+        )
+
         snapshots = mk.extract_frames(
             video_url=video_url,
             strategy="SpecifiedFrames",
             max_frames=max_frames,
-            poll_interval=2.0,
-            max_poll_attempts=5,
-            max_retries=0,
+            poll_interval=COVER_POLL_INTERVAL,
+            max_poll_attempts=COVER_MAX_POLL_ATTEMPTS,
+            max_retries=1,
         )
         if not snapshots:
             logger.warning("[数字人封面] MediaKit 未返回帧: %s", video_url[:80])
@@ -55,24 +107,26 @@ def select_best_cover_frame(video_url: str, *, max_frames: int = 5) -> str:
         if len(snapshots) == 1:
             return snapshots[0].get("image_url") or snapshots[0].get("url") or ""
 
-        # 下载各帧评分
+        # 使用连接池下载各帧（复用 TCP 连接，减少延迟）
         import httpx
 
         candidates = []
-        for snap in snapshots:
-            url = snap.get("image_url") or snap.get("url") or ""
-            if not url:
-                continue
-            tmp_path: Optional[str] = None
-            try:
-                resp = httpx.get(url, timeout=15, follow_redirects=True)
-                resp.raise_for_status()
-                with tempfile.NamedTemporaryFile(suffix=".jpg", delete=False) as tmp:
-                    tmp.write(resp.content)
-                    tmp_path = tmp.name
-                candidates.append({"image_path": tmp_path, "url": url})
-            except Exception:
-                candidates.append({"image_path": None, "url": url, "score": 0.0})
+        with httpx.Client(timeout=FRAME_DOWNLOAD_TIMEOUT, follow_redirects=True) as client:
+            for snap in snapshots:
+                url = snap.get("image_url") or snap.get("url") or ""
+                if not url:
+                    continue
+                tmp_path: Optional[str] = None
+                try:
+                    resp = client.get(url)
+                    resp.raise_for_status()
+                    with tempfile.NamedTemporaryFile(suffix=".jpg", delete=False) as tmp:
+                        tmp.write(resp.content)
+                        tmp_path = tmp.name
+                    candidates.append({"image_path": tmp_path, "url": url})
+                except Exception as e:
+                    logger.warning("[数字人封面] 帧下载失败，跳过: url=%s err=%s", url[:80], e)
+                    candidates.append({"image_path": None, "url": url, "score": 0.0})
 
         if not candidates:
             return snapshots[0].get("image_url") or snapshots[0].get("url") or ""
@@ -119,14 +173,16 @@ def persist_cover_to_oss(frame_url: str, *, job_id: str = "", prefix: str = "ai-
     try:
         import httpx
 
-        resp = httpx.get(frame_url, timeout=30, follow_redirects=True)
-        resp.raise_for_status()
-        if not resp.content:
-            return frame_url
+        with httpx.Client(timeout=BEST_FRAME_DOWNLOAD_TIMEOUT, follow_redirects=True) as client:
+            resp = client.get(frame_url)
+            resp.raise_for_status()
+            if not resp.content:
+                logger.warning("[数字人封面] 帧图内容为空: %s", frame_url[:80])
+                return frame_url
 
-        with tempfile.NamedTemporaryFile(suffix=".jpg", delete=False) as tmp:
-            tmp.write(resp.content)
-            tmp_path = tmp.name
+            with tempfile.NamedTemporaryFile(suffix=".jpg", delete=False) as tmp:
+                tmp.write(resp.content)
+                tmp_path = tmp.name
 
         from packages.shared.storage import get_shared_storage_service
 

tests/unit/test_ai_avatar_emotion_tts_lipsync.py

@@ -233,7 +233,7 @@ def test_smart_cover_selects_best_frame_and_persists():
     with (
         patch("packages.shared.mediakit_client.get_mediakit_client") as mk_patch,
         patch("packages.shared.cover_frame_scorer.score_frames") as score_patch,
-        patch("httpx.get") as http_get,
+        patch("httpx.Client") as http_client_cls,
         patch("packages.shared.storage.get_shared_storage_service") as storage_patch,
     ):
         mk = MagicMock()
@@ -245,32 +245,107 @@ def test_smart_cover_selects_best_frame_and_persists():
             {"url": "https://mk/f1.jpg", "score": 90.0, "image_path": cands[1]["image_path"]},
             {"url": "https://mk/f0.jpg", "score": 60.0, "image_path": cands[0]["image_path"]},
         ]
+        # httpx.Client 连接池 mock
+        client_instance = MagicMock()
         resp = MagicMock()
         resp.content = b"IMGDATA"
         resp.raise_for_status = MagicMock()
-        http_get.return_value = resp
+        client_instance.get.return_value = resp
+        client_instance.__enter__ = MagicMock(return_value=client_instance)
+        client_instance.__exit__ = MagicMock(return_value=False)
+        http_client_cls.return_value = client_instance
+
         storage = MagicMock()
-        storage.upload_file.return_value = "https://oss/cover.jpg"
+        storage.public_url = "https://oss.example.com"
+        # video_url 不是自家 OSS，不重签
+        storage.get_download_url.side_effect = lambda url, **kw: f"{url}?signed=1"
+        storage.upload_file.return_value = "https://oss.example.com/cover.jpg"
         storage_patch.return_value = storage
 
-        url = cov.generate_smart_cover("https://oss/avatar.mp4", job_id="job-1")
+        url = cov.generate_smart_cover("https://other-host/avatar.mp4", job_id="job-1")
 
-    assert url == "https://oss/cover.jpg"
+    assert "signed=1" in url or url == "https://oss.example.com/cover.jpg"
     mk.extract_frames.assert_called_once()
     score_patch.assert_called_once()
+    # 验证使用了增大的轮询参数
+    call_kwargs = mk.extract_frames.call_args
+    assert call_kwargs.kwargs.get("poll_interval") == 3.0 or call_kwargs[1].get("poll_interval") == 3.0
+    assert call_kwargs.kwargs.get("max_poll_attempts") == 20 or call_kwargs[1].get("max_poll_attempts") == 20
 
 
 def test_smart_cover_returns_empty_when_mediakit_unavailable():
     from app.services import ai_avatar_cover_service as cov
 
-    with patch("packages.shared.mediakit_client.get_mediakit_client") as mk_patch:
+    with (
+        patch("packages.shared.mediakit_client.get_mediakit_client") as mk_patch,
+        patch("packages.shared.storage.get_shared_storage_service") as storage_patch,
+    ):
         mk = MagicMock()
         mk.is_available = False
         mk_patch.return_value = mk
-        url = cov.generate_smart_cover("https://oss/avatar.mp4")
+        storage = MagicMock()
+        storage.public_url = "https://oss.example.com"
+        storage_patch.return_value = storage
+        url = cov.generate_smart_cover("https://oss.example.com/avatar.mp4")
     assert url == ""
 
 
+def test_sign_video_url_resigns_own_oss_url():
+    """自家 OSS 私有桶 URL 应被重签为长有效期预签名 URL"""
+    from app.services.ai_avatar_cover_service import _sign_video_url_for_mediakit
+
+    with patch("packages.shared.storage.get_shared_storage_service") as storage_patch:
+        storage = MagicMock()
+        storage.public_url = "https://oss.example.com"
+        storage.get_download_url.return_value = "https://oss.example.com/file.mp4?Expires=xxx&Signature=yyy"
+        storage_patch.return_value = storage
+
+        result = _sign_video_url_for_mediakit("https://oss.example.com/file.mp4")
+
+    assert "Signature=yyy" in result
+    storage.get_download_url.assert_called_once()
+
+
+def test_sign_video_url_skips_external_url():
+    """外部 URL（非自家 OSS）应原样返回，不做重签"""
+    from app.services.ai_avatar_cover_service import _sign_video_url_for_mediakit
+
+    with patch("packages.shared.storage.get_shared_storage_service") as storage_patch:
+        storage = MagicMock()
+        storage.public_url = "https://oss.example.com"
+        storage_patch.return_value = storage
+
+        result = _sign_video_url_for_mediakit("https://external-cdn.com/video.mp4")
+
+    assert result == "https://external-cdn.com/video.mp4"
+    storage.get_download_url.assert_not_called()
+
+
+def test_extract_frames_uses_extended_poll_params():
+    """验证 select_best_cover_frame 使用增大后的轮询参数"""
+    from app.services import ai_avatar_cover_service as cov
+
+    with (
+        patch("packages.shared.mediakit_client.get_mediakit_client") as mk_patch,
+        patch("packages.shared.storage.get_shared_storage_service") as storage_patch,
+    ):
+        mk = MagicMock()
+        mk.is_available = True
+        mk.extract_frames.return_value = [{"image_url": "https://mk/f0.jpg"}]
+        mk_patch.return_value = mk
+
+        storage = MagicMock()
+        storage.public_url = "https://oss.example.com"
+        storage_patch.return_value = storage
+
+        cov.select_best_cover_frame("https://other/avatar.mp4", max_frames=3)
+
+    call_kwargs = mk.extract_frames.call_args
+    assert call_kwargs.kwargs.get("poll_interval") == 3.0 or call_kwargs[1].get("poll_interval") == 3.0
+    assert call_kwargs.kwargs.get("max_poll_attempts") == 20 or call_kwargs[1].get("max_poll_attempts") == 20
+    assert call_kwargs.kwargs.get("max_retries") == 1 or call_kwargs[1].get("max_retries") == 1
+
+
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