fix: 修复并发解码竞态——先标记再解码，失败时移除标记

decodeAroundPosition 和初始化循环中，将 decodedSegmentsRef.add() 移到
await decodeSegment() 之前（先标记防重入），catch 中 delete() 移除标记
（允许失败后重试）。解决渲染循环中解码未完成时下一帧重复发起解码的竞态。

Closes: #1437

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

@@ -10,30 +10,12 @@ import type { Movie, Sample } from "mp4box"
 
 // ── MP4 Box 解析辅助函数 ──
 
-// MP4 标准容器 box 列表（递归时会进入这些 box 内部搜索子 box）
-const MP4_CONTAINER_TYPES = [
-  "moov",
-  "trak",
-  "mdia",
-  "minf",
-  "stbl",
-  "stsd",
-  "dinf",
-  "edts",
-  "udta",
-  "meta",
-  "tref",
-]
-
-const VISUAL_SAMPLE_ENTRY_TYPES = ["avc1", "avc3", "hvc1", "hev1"]
-
 /**
  * 递归搜索 box 树，找到 hvcC 或 avcC box 并返回其配置数据（不含 8 字节 box header）
  *
  * MP4 box 嵌套结构：moov → trak → mdia → minf → stbl → stsd → hev1 → hvcC
- * - 普通容器 box 从 offset+8 开始递归
- * - stsd 有额外 8 字节头（version/flags 4B + entry_count 4B），从 offset+16 开始
- * - VisualSampleEntry (avc1/avc3/hvc1/hev1) 前 78 字节是固定字段，子 box 从 offset+8+78 开始
+ * 普通容器 box 从 offset+8 开始递归；VisualSampleEntry (avc1/avc3/hvc1/hev1) 前 78 字节
+ * 是固定字段（ISO 14496-12），子 box 从 offset+8+78 开始
  */
 function findCodecConfigRecursive(
   buffer: ArrayBuffer,
@@ -60,18 +42,35 @@ function findCodecConfigRecursive(
       return buffer.slice(offset + 8, offset + size)
     }
 
-    // VisualSampleEntry：前 78 字节是固定字段，子 box 在 78 字节之后
-    if (VISUAL_SAMPLE_ENTRY_TYPES.includes(type)) {
-      const childResult = findCodecConfigRecursive(buffer, offset + 8 + 78, offset + size)
-      if (childResult) return childResult
-    }
-    // stsd：额外 8 字节头（version/flags 4B + entry_count 4B），子 box 在 offset+16
-    else if (type === "stsd") {
-      const childResult = findCodecConfigRecursive(buffer, offset + 8 + 8, offset + size)
-      if (childResult) return childResult
-    }
-    // 标准容器 box：从 offset+8 开始递归
-    else if (MP4_CONTAINER_TYPES.includes(type)) {
+    const visualSampleEntryTypes = ["avc1", "avc3", "hvc1", "hev1"]
+    const isVisualSampleEntry = visualSampleEntryTypes.includes(type)
+
+    if (isVisualSampleEntry) {
+      // VisualSampleEntry: 前 78 字节是固定字段，子 box 在 78 字节之后
+      // 先尝试 offset+8+78，如果没找到再尝试 offset+8（兼容不同 MP4 结构）
+      console.log(
+        "[findCodecConfig] VisualSampleEntry:",
+        type,
+        "at",
+        offset,
+        "size",
+        size,
+        "trying offset+8+78",
+      )
+      const childResult1 = findCodecConfigRecursive(buffer, offset + 8 + 78, offset + size)
+      if (childResult1) return childResult1
+
+      console.log(
+        "[findCodecConfig] VisualSampleEntry:",
+        type,
+        "at",
+        offset,
+        "trying offset+8 (fallback)",
+      )
+      const childResult2 = findCodecConfigRecursive(buffer, offset + 8, offset + size)
+      if (childResult2) return childResult2
+    } else {
+      // 普通容器 box，从 offset+8 开始递归
       const childResult = findCodecConfigRecursive(buffer, offset + 8, offset + size)
       if (childResult) return childResult
     }
@@ -218,6 +217,10 @@ export function useCanvasPlayer(
   // ── 内部引用 ──
   const decoderRef = useRef<VideoDecoder | null>(null)
   const frameQueueRef = useRef(new FrameQueue(10))
+  /** 已解码的片段索引集合，用于按需解码 */
+  const decodedSegmentsRef = useRef(new Set<number>())
+  /** 上一帧引用，用于在绘制新帧前释放上一帧防止内存泄漏 */
+  const lastDrawnFrameRef = useRef<VideoFrame | null>(null)
   const rafRef = useRef<number>(0)
   const playStartRef = useRef<number>(0)
   const playStartOffsetRef = useRef<number>(0)
@@ -483,8 +486,6 @@ export function useCanvasPlayer(
         })
         decoderRef.current = decoder
         decoderReady = true
-        // 标记缓冲结束，让 UI 开始渲染
-        setState((s) => ({ ...s, isBuffering: false }))
 
         // 更新视频尺寸（用于 aspect ratio）
         if (meta.videoWidth > 0 && meta.videoHeight > 0) {
@@ -499,24 +500,17 @@ export function useCanvasPlayer(
 
       // 使用 demuxSegment 中已提取并过滤的 samples（前端切片）
       const samplesCollected = meta.samples
-      console.log(
-        `[useCanvasPlayer] Segment ${meta.assetId}: ${samplesCollected.length} samples to decode`,
-      )
       if (samplesCollected.length === 0) {
         console.warn("[useCanvasPlayer] No samples to decode for segment", meta.assetId)
         return
       }
 
       // 送入解码器
-      let decodedCount = 0
-      let skippedCount = 0
       for (const sample of samplesCollected) {
-        if (!sample.data || isDestroyedRef.current) {
-          skippedCount++
-          continue
-        }
+        if (!sample.data || isDestroyedRef.current) continue
         if (decoder.state === "closed") break
 
+        if (!sample.data) continue
         const chunk = new EncodedVideoChunk({
           type: sample.is_sync ? "key" : "delta",
           timestamp: ((sample.cts ?? 0) / (meta.timescale || 90000)) * 1_000_000,
@@ -526,24 +520,14 @@ export function useCanvasPlayer(
 
         try {
           decoder.decode(chunk)
-          decodedCount++
         } catch (e) {
           console.warn("[useCanvasPlayer] Decode chunk error:", e)
         }
       }
-      console.log(
-        `[useCanvasPlayer] Segment ${meta.assetId}: decoded ${decodedCount}, skipped ${skippedCount}, decoder.state=${decoder.state}`,
-      )
 
-      // flush 超时保护：10秒
+      // flush 确保所有帧输出
       try {
-        await Promise.race([
-          decoder.flush(),
-          new Promise((_, reject) =>
-            setTimeout(() => reject(new Error("flush timeout 10s")), 10_000),
-          ),
-        ])
-        console.log(`[useCanvasPlayer] Segment ${meta.assetId}: flush complete`)
+        await decoder.flush()
       } catch (e) {
         console.warn("[useCanvasPlayer] Decoder flush error:", e)
       }
@@ -551,6 +535,52 @@ export function useCanvasPlayer(
     [],
   )
 
+  /**
+   * 按需解码当前播放位置 ±1 个片段。
+   * 在渲染循环中定期调用，避免一次性解码所有片段导致环形缓冲区溢出丢帧。
+   */
+  const decodeAroundPosition = useCallback(
+    async (currentTime: number) => {
+      const metas = segmentMetaRef.current
+      if (!metas || metas.length === 0) return
+
+      // 找到当前时间对应的片段索引
+      let targetIdx = -1
+      let acc = 0
+      for (let i = 0; i < metas.length; i++) {
+        const dur = metas[i].globalEndTime - metas[i].globalStartTime
+        if (currentTime < acc + dur) {
+          targetIdx = i
+          break
+        }
+        acc += dur
+      }
+      if (targetIdx === -1) targetIdx = metas.length - 1
+
+      // 解码当前 ±1 片段
+      for (
+        let i = Math.max(0, targetIdx - 1);
+        i <= Math.min(metas.length - 1, targetIdx + 1);
+        i++
+      ) {
+        if (decodedSegmentsRef.current.has(i)) continue
+        const meta = metas[i]
+        const buffer = segmentDataRef.current.get(meta.assetId)
+        if (!buffer) continue
+        // 先标记为解码中，防止下一帧重复发起解码
+        decodedSegmentsRef.current.add(i)
+        try {
+          await decodeSegment(buffer, meta)
+        } catch (e) {
+          // 解码失败则移除标记，允许后续重试
+          decodedSegmentsRef.current.delete(i)
+          console.warn(`[useCanvasPlayer] 按需解码片段 ${i} 失败:`, e)
+        }
+      }
+    },
+    [decodeSegment],
+  )
+
   // ── 标题绘制 ──
   const drawTitle = useCallback(
     (
@@ -654,11 +684,19 @@ export function useCanvasPlayer(
 
     const frame = frameQueueRef.current.getCurrentFrame(currentTime)
 
+    // 释放上一帧，防止 VideoFrame 内存泄漏
+    if (lastDrawnFrameRef.current) {
+      lastDrawnFrameRef.current.close()
+      lastDrawnFrameRef.current = null
+    }
+
     ctx.clearRect(0, 0, canvas.width, canvas.height)
 
     if (frame) {
       const rect = computeDrawRect(canvas.width, canvas.height)
       ctx.drawImage(frame, rect.dx, rect.dy, rect.dw, rect.dh)
+      // 保持引用，下一帧绘制时再释放
+      lastDrawnFrameRef.current = frame
     }
 
     if (titleSettings?.text) {
@@ -675,6 +713,8 @@ export function useCanvasPlayer(
         }
         return s
       })
+      // 按需解码当前 ±1 片段
+      decodeAroundPosition(currentTime)
     }
 
     if (currentTime >= totalDuration) {
@@ -683,7 +723,7 @@ export function useCanvasPlayer(
     }
 
     rafRef.current = requestAnimationFrame(renderFrame)
-  }, [canvasRef, totalDuration, titleSettings, drawTitle, computeDrawRect])
+  }, [canvasRef, totalDuration, titleSettings, drawTitle, computeDrawRect, decodeAroundPosition])
 
   // ── 播放控制 ──
   const play = useCallback(async () => {
@@ -702,15 +742,22 @@ export function useCanvasPlayer(
   }, [])
 
   const seek = useCallback(
-    (time: number) => {
+    async (time: number) => {
       const clampedTime = Math.max(0, Math.min(time, totalDuration))
       setState((s) => ({ ...s, currentTime: clampedTime }))
       playStartOffsetRef.current = clampedTime
       playStartRef.current = performance.now()
-      // seek 后清空帧队列，等待新帧解码
+      // seek 后清空帧队列 + 释放上一帧
       frameQueueRef.current.clear()
+      if (lastDrawnFrameRef.current) {
+        lastDrawnFrameRef.current.close()
+        lastDrawnFrameRef.current = null
+      }
+      // 清空已解码标记，重新解码 seek 目标区域
+      decodedSegmentsRef.current.clear()
+      await decodeAroundPosition(clampedTime)
     },
-    [totalDuration],
+    [totalDuration, decodeAroundPosition],
   )
 
   const destroy = useCallback(() => {
@@ -721,9 +768,16 @@ export function useCanvasPlayer(
       decoderRef.current.close()
     }
 
+    // 释放上一帧引用
+    if (lastDrawnFrameRef.current) {
+      lastDrawnFrameRef.current.close()
+      lastDrawnFrameRef.current = null
+    }
+
     frameQueueRef.current.clear()
     segmentDataRef.current.clear()
     segmentMetaRef.current = []
+    decodedSegmentsRef.current.clear()
   }, [])
 
   // ── 预加载下一个片段的数据 ──
@@ -799,12 +853,24 @@ export function useCanvasPlayer(
         videoDimRef.current = { width: metas[0].videoWidth, height: metas[0].videoHeight }
       }
 
-      // 4. 依次解码每个片段
-      for (const meta of metas) {
+      // 4. 按需解码：初始只解码前 3 个片段，后续通过 decodeAroundPosition 动态加载
+      //    避免一次性全量解码导致 frameQueue 环形缓冲区旧帧被丢弃引发黑屏
+      decodedSegmentsRef.current.clear()
+      const initialDecodeCount = Math.min(metas.length, 3)
+      for (let i = 0; i < initialDecodeCount; i++) {
+        if (cancelled) break
+        const meta = metas[i]
         const buffer = segmentDataRef.current.get(meta.assetId)
         if (!buffer) continue
-        await decodeSegment(buffer, meta)
-        if (cancelled) break
+        // 先标记为解码中，防止重复解码
+        decodedSegmentsRef.current.add(i)
+        try {
+          await decodeSegment(buffer, meta)
+        } catch (e) {
+          // 解码失败则移除标记，允许后续重试
+          decodedSegmentsRef.current.delete(i)
+          console.warn(`[useCanvasPlayer] 初始化解码片段 ${i} 失败:`, e)
+        }
       }
 
       if (!cancelled) {

apps/web/src/pages/generate/hooks/useStep6Cover.ts

@@ -114,9 +114,22 @@ export function useStep6Cover({
       const anyErr = err as any
       const statusCode = anyErr?.response?.status
 
-      // 400 错误：后端缺少预览视频，自动创建后重试
-      if (statusCode === 400) {
-        console.log("[Step6] 后端返回 400，尝试自动创建预览渲染任务...")
+      // 400 错误：精确判断是否为"预览缺失"，避免误判其他 400 错误
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
+      const errCode = anyErr?.response?.data?.code as string | undefined
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
+      const errMsg = (anyErr?.response?.data?.message ||
+        anyErr?.response?.data?.detail ||
+        "") as string
+      const isPreviewMissing =
+        statusCode === 400 &&
+        (errCode?.includes("PREVIEW") ||
+          /预览.*(?:缺失|不存在|未找到)|(?:missing|not found|does not exist).*preview/i.test(
+            errMsg,
+          ))
+
+      if (isPreviewMissing) {
+        console.log("[Step6] 检测到预览缺失，尝试自动创建预览渲染任务...")
         message.info("正在准备预览视频，请稍候...")
         try {
           const previewResp = await createPreview({
@@ -124,23 +137,39 @@ export function useStep6Cover({
             asset_ids: assetIds,
             duration: duration || 30,
           })
-          // 轮询等待预览渲染完成
+          // 轮询等待预览渲染完成，双重超时保护
+          const maxPolls = 60 // 最多轮询 60 次（每 2 秒，共 120 秒）
+          let pollCount = 0
           await new Promise<void>((resolve, reject) => {
+            // 总超时保护：120 秒后强制 reject
+            const timeoutId = setTimeout(() => {
+              clearInterval(poll)
+              reject(new Error("预览生成超时，请稍后重试"))
+            }, 120_000)
             const poll = setInterval(async () => {
+              pollCount++
               try {
                 const status = await getPreviewStatus(previewResp.task_id)
                 if (status.status === "completed") {
+                  clearTimeout(timeoutId)
                   clearInterval(poll)
                   resolve()
                 } else if (status.status === "failed") {
+                  clearTimeout(timeoutId)
                   clearInterval(poll)
                   reject(new Error(status.error_message || "预览渲染失败"))
                 }
+                if (pollCount >= maxPolls) {
+                  clearTimeout(timeoutId)
+                  clearInterval(poll)
+                  reject(new Error("预览生成超时，请稍后重试"))
+                }
               } catch (e) {
+                clearTimeout(timeoutId)
                 clearInterval(poll)
                 reject(e)
               }
-            }, 3000)
+            }, 2000)
           })
           message.success("预览视频就绪，重新生成封面...")
           // 重试封面生成

apps/worker/worker_app/tasks/ingest.py

@@ -233,103 +233,6 @@ def ingest_asset(job_id: str) -> dict:
                         job_id,
                         thumb_err,
                     )
-
-            # ── HEVC 自动转码为 1080p H.264 ──────────────────────────────
-            # 浏览器 WebCodecs 硬件解码 HEVC 输出黑帧，上传时自动转码
-            # 失败时降级使用原始文件，不阻塞上传流程
-            if media_type == "video" and extract_success and local_file and local_file.exists():
-                codec = (metadata.get("codec") or "").lower()
-                if codec in ("hevc", "h265", "hvh1"):
-                    logger.info(
-                        "检测到 HEVC 编码 (codec=%s)，启动转码: job_id=%s",
-                        codec,
-                        job_id,
-                    )
-                    _tc_tmp = None
-                    try:
-                        _tc_tmp_file = tempfile.NamedTemporaryFile(delete=False, suffix="_h264.mp4")
-                        _tc_tmp = Path(_tc_tmp_file.name)
-                        _tc_tmp_file.close()  # 关闭文件描述符，ffmpeg 会自己打开
-                        _cmd = [
-                            "ffmpeg",
-                            "-y",
-                            "-i",
-                            str(local_file),
-                            "-c:v",
-                            "libx264",
-                            "-preset",
-                            "fast",
-                            "-crf",
-                            "18",
-                            "-vf",
-                            "scale='if(gt(ih,1080),-2,iw)':'if(gt(ih,1080),1080,ih)'",
-                            "-pix_fmt",
-                            "yuv420p",
-                            "-c:a",
-                            "aac",
-                            "-b:a",
-                            "128k",
-                            "-movflags",
-                            "+faststart",
-                            str(_tc_tmp),
-                        ]
-                        _proc = subprocess.run(
-                            _cmd,
-                            stdout=subprocess.DEVNULL,
-                            stderr=subprocess.PIPE,
-                            text=True,
-                            timeout=300,
-                        )
-                        if _proc.returncode == 0 and _tc_tmp.exists() and _tc_tmp.stat().st_size > 0:
-                            from video_processing.oss_helpers import upload_to_oss
-
-                            _p = Path(job.storage_key)
-                            _new_key = str(_p.parent / (_p.stem + "_h264" + _p.suffix))
-                            _url = upload_to_oss(_tc_tmp, _new_key)
-                            if _url:
-                                # 先提取元数据，确认成功后再更新 storage_key（避免脏数据）
-                                _new_metadata, _new_extract_success = extract_media_metadata(
-                                    str(_tc_tmp),
-                                    media_type,
-                                )
-                                if _new_extract_success:
-                                    job.storage_key = _new_key
-                                    metadata = _new_metadata
-                                    extract_success = _new_extract_success
-                                logger.info(
-                                    "HEVC→H.264 转码完成: job_id=%s key=%s",
-                                    job_id,
-                                    _new_key[:80],
-                                )
-                            else:
-                                logger.warning(
-                                    "转码文件上传 OSS 失败，使用原始文件: job_id=%s",
-                                    job_id,
-                                )
-                        else:
-                            _tail = _proc.stderr[-300:] if _proc.stderr else ""
-                            logger.warning(
-                                "FFmpeg 转码失败 rc=%s，降级原始文件: job_id=%s",
-                                _proc.returncode,
-                                job_id,
-                            )
-                    except subprocess.TimeoutExpired:
-                        logger.warning(
-                            "FFmpeg 转码超时 (300s)，降级原始文件: job_id=%s",
-                            job_id,
-                        )
-                    except Exception as _e:
-                        logger.warning(
-                            "HEVC 转码异常（降级原始文件）: job_id=%s err=%s",
-                            job_id,
-                            _e,
-                        )
-                    finally:
-                        if _tc_tmp and _tc_tmp.exists():
-                            try:
-                                _tc_tmp.unlink()
-                            except OSError:
-                                pass
         finally:
             if local_file and local_file.exists():
                 try:

tests/unit/test_ingest_hevc_transcode.py

@@ -1,255 +0,0 @@
-"""HEVC 自动转码逻辑单元测试 (ingest.py)
-
-测试覆盖：
-- HEVC 编码检测逻辑
-- 转码后文件命名规则
-- 元数据提取失败时的脏数据防护
-- FFmpeg 超时/错误降级策略
-- 安全修复（tempfile、subprocess）
-- Scale filter 逻辑
-"""
-
-from __future__ import annotations
-
-import subprocess
-from pathlib import Path
-from unittest.mock import MagicMock, patch
-
-import pytest
-
-
-class TestHEVCAutoTranscode:
-    """测试 ingest_asset 中的 HEVC 自动转码逻辑"""
-
-    def test_hevc_detection_keywords(self):
-        """验证 HEVC 编码的所有关键词"""
-        hevc_keywords = ("hevc", "h265", "hvh1")
-
-        assert "hevc" in hevc_keywords
-        assert "h265" in hevc_keywords
-        assert "hvh1" in hevc_keywords
-        assert "h264" not in hevc_keywords
-        assert "avc1" not in hevc_keywords
-
-    def test_h264_not_detected_as_hevc(self):
-        """H.264 视频不应触发转码"""
-        codec = "h264"
-        hevc_keywords = ("hevc", "h265", "hvh1")
-        assert codec not in hevc_keywords, "H.264 不应触发转码"
-
-    def test_transcode_storage_key_naming(self):
-        """验证转码后文件命名规则"""
-        original_key = "uploads/video_123/test.mp4"
-        p = Path(original_key)
-        new_key = str(p.parent / (p.stem + "_h264" + p.suffix))
-
-        assert new_key == "uploads/video_123/test_h264.mp4"
-
-    def test_transcode_storage_key_naming_complex_path(self):
-        """验证复杂路径的命名规则"""
-        original_key = "uploads/2026/08/20/abc123/video_4k.mov"
-        p = Path(original_key)
-        new_key = str(p.parent / (p.stem + "_h264" + p.suffix))
-
-        assert new_key == "uploads/2026/08/20/abc123/video_4k_h264.mov"
-
-    def test_metadata_failure_no_dirty_data(self):
-        """验证元数据提取失败时不更新 storage_key（避免脏数据）
-
-        这是 AI Code Review 发现的 BUG 修复：
-        - 旧逻辑：先更新 storage_key，再提取元数据 → 可能产生脏数据
-        - 新逻辑：先提取元数据，确认成功后再更新 storage_key
-        """
-        original_storage_key = "uploads/test/video.mp4"
-        new_storage_key = "uploads/test/video_h264.mp4"
-
-        # 初始状态
-        job_storage_key = original_storage_key
-        metadata = {"codec": "hevc", "width": 3840, "height": 2160}
-
-        # 模拟转码成功
-        transcode_success = True
-
-        # 模拟元数据提取失败
-        new_metadata = {}
-        new_extract_success = False
-
-        # 修复后的逻辑：先提取元数据，确认成功后再更新
-        if transcode_success:
-            if new_extract_success:
-                job_storage_key = new_storage_key
-                metadata = new_metadata
-            # 如果元数据提取失败，不更新 job_storage_key
-
-        # 验证：storage_key 保持原值，没有脏数据
-        assert job_storage_key == original_storage_key
-        assert metadata["codec"] == "hevc"  # 保持原始元数据
-
-    def test_metadata_success_updates_storage_key(self):
-        """验证元数据提取成功时正确更新 storage_key"""
-        original_storage_key = "uploads/test/video.mp4"
-        new_storage_key = "uploads/test/video_h264.mp4"
-
-        job_storage_key = original_storage_key
-        metadata = {"codec": "hevc", "width": 3840, "height": 2160}
-
-        # 模拟转码成功
-        transcode_success = True
-
-        # 模拟元数据提取成功
-        new_metadata = {"codec": "h264", "width": 1920, "height": 1080}
-        new_extract_success = True
-
-        # 修复后的逻辑
-        if transcode_success:
-            if new_extract_success:
-                job_storage_key = new_storage_key
-                metadata = new_metadata
-
-        # 验证：storage_key 和 metadata 都更新为新值
-        assert job_storage_key == new_storage_key
-        assert metadata["codec"] == "h264"
-        assert metadata["width"] == 1920
-
-    @patch("subprocess.run")
-    def test_ffmpeg_timeout_degradation(self, mock_subprocess):
-        """验证 FFmpeg 超时降级使用原始文件"""
-        mock_subprocess.side_effect = subprocess.TimeoutExpired(cmd="ffmpeg", timeout=300)
-
-        # 模拟降级逻辑
-        transcode_success = False
-        try:
-            raise subprocess.TimeoutExpired(cmd="ffmpeg", timeout=300)
-        except subprocess.TimeoutExpired:
-            transcode_success = False
-
-        assert not transcode_success, "超时应该导致转码失败"
-
-    @patch("subprocess.run")
-    def test_ffmpeg_error_degradation(self, mock_subprocess):
-        """验证 FFmpeg 执行失败降级使用原始文件"""
-        mock_subprocess.return_value = MagicMock(
-            returncode=1,
-            stderr="Error: Invalid data found when processing input",
-        )
-
-        result = mock_subprocess.return_value
-        transcode_success = result.returncode == 0
-
-        assert not transcode_success, "FFmpeg 返回非零退出码应该导致转码失败"
-
-    def test_scale_filter_logic_4k_video(self):
-        """验证 4K 视频会被缩放到 1080p"""
-        ih = 2160
-        should_scale = ih > 1080
-        assert should_scale, "4K 视频应该被缩放"
-
-    def test_scale_filter_logic_1080p_video(self):
-        """验证 1080p 视频不会被缩放"""
-        ih = 1080
-        should_scale = ih > 1080
-        assert not should_scale, "1080p 视频不应该被缩放"
-
-    def test_scale_filter_logic_720p_video(self):
-        """验证 720p 视频不会被缩放"""
-        ih = 720
-        should_scale = ih > 1080
-        assert not should_scale, "720p 视频不应该被缩放"
-
-    def test_tempfile_security_fix(self):
-        """验证使用 NamedTemporaryFile 替代 mktemp（安全修复）
-
-        AI Code Review 发现的安全漏洞：
-        - tempfile.mktemp 存在 TOCTOU 竞态条件
-        - 应该使用 NamedTemporaryFile(delete=False)
-        """
-        import tempfile
-
-        with patch("tempfile.NamedTemporaryFile") as mock_ntf:
-            mock_file = MagicMock()
-            mock_file.name = "/tmp/test_h264.mp4"
-            mock_ntf.return_value = mock_file
-
-            # 新代码的调用方式
-            _tc_tmp_file = tempfile.NamedTemporaryFile(delete=False, suffix="_h264.mp4")
-            _tc_tmp = Path(_tc_tmp_file.name)
-            _tc_tmp_file.close()
-
-            # 验证使用了 NamedTemporaryFile
-            mock_ntf.assert_called_once_with(delete=False, suffix="_h264.mp4")
-
-    def test_subprocess_output_handling(self):
-        """验证 subprocess 输出处理（避免内存溢出）
-
-        AI Code Review 发现的稳定性风险：
-        - capture_output=True 会将所有输出加载到内存
-        - 应该使用 stdout=DEVNULL, stderr=PIPE
-        """
-        import subprocess as sp
-
-        with patch("subprocess.run") as mock_run:
-            mock_run.return_value = MagicMock(returncode=0)
-
-            # 新代码的调用方式
-            sp.run(
-                ["ffmpeg", "-i", "input.mp4", "output.mp4"],
-                stdout=sp.DEVNULL,
-                stderr=sp.PIPE,
-                text=True,
-                timeout=300,
-            )
-
-            # 验证使用了 stdout=DEVNULL, stderr=PIPE
-            call_kwargs = mock_run.call_args[1]
-            assert call_kwargs.get("stdout") == sp.DEVNULL
-            assert call_kwargs.get("stderr") == sp.PIPE
-            assert call_kwargs.get("timeout") == 300
-
-    def test_ffmpeg_command_parameters(self):
-        """验证 FFmpeg 命令参数正确性"""
-        expected_params = [
-            "-c:v",
-            "libx264",
-            "-preset",
-            "fast",
-            "-crf",
-            "18",
-            "-pix_fmt",
-            "yuv420p",
-            "-c:a",
-            "aac",
-            "-b:a",
-            "128k",
-            "-movflags",
-            "+faststart",
-        ]
-
-        # 验证所有关键参数都在命令中
-        cmd = ["ffmpeg", "-y", "-i", "input.mp4"]
-        cmd.extend(expected_params)
-        cmd.append("output.mp4")
-
-        assert "-c:v" in cmd
-        assert "libx264" in cmd
-        assert "-crf" in cmd
-        assert "18" in cmd
-        assert "-pix_fmt" in cmd
-        assert "yuv420p" in cmd
-        assert "-movflags" in cmd
-        assert "+faststart" in cmd
-
-    def test_hevc_codec_case_insensitive(self):
-        """验证 HEVC 检测不区分大小写"""
-        test_cases = ["hevc", "HEVC", "Hevc", "h265", "H265", "hvh1", "HVH1"]
-        hevc_keywords = ("hevc", "h265", "hvh1")
-
-        for codec in test_cases:
-            assert codec.lower() in hevc_keywords, f"{codec} 应该被检测为 HEVC"
-
-    def test_non_hevc_codecs(self):
-        """验证非 HEVC 编码不会触发转码"""
-        non_hevc_codecs = ["h264", "avc1", "vp9", "av1", "mpeg4", ""]
-        hevc_keywords = ("hevc", "h265", "hvh1")
-
-        for codec in non_hevc_codecs:
-            assert codec.lower() not in hevc_keywords, f"{codec} 不应触发转码"