diff --git a/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts b/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
index cb9593659..884c76633 100644
--- a/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
+++ b/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
@@ -567,11 +567,13 @@ export function useCanvasPlayer(
         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)
-          // 解码成功后才标记，失败时下次重试
-          decodedSegmentsRef.current.add(i)
         } 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)
         }
       }
@@ -860,11 +862,13 @@ export function useCanvasPlayer(
         const meta = metas[i]
         const buffer = segmentDataRef.current.get(meta.assetId)
         if (!buffer) continue
+        // 先标记为解码中，防止重复解码
+        decodedSegmentsRef.current.add(i)
         try {
           await decodeSegment(buffer, meta)
-          // 解码成功后才标记，失败时不标记以便后续重试
-          decodedSegmentsRef.current.add(i)
         } 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)
         }
       }