From c3373de4f39d8d6dade99150bd8aee750aaaec75 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=BC=A0=E5=AE=8F=E6=9D=B0?=
 <zhanghongjie@xiaoxiajianji.com>
Date: Wed, 19 Aug 2026 20:29:46 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20findCodecConfig=20=E5=8A=A8=E6=80=81?=
 =?UTF-8?q?=E6=A3=80=E6=B5=8B=20fullbox=EF=BC=8C=E4=BF=AE=E5=A4=8D=20conta?=
 =?UTF-8?q?iner=20box=20=E5=81=8F=E7=A7=BB=E8=AE=A1=E7=AE=97=E9=94=99?=
 =?UTF-8?q?=E8=AF=AF?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

问题根因：
- 代码假设所有 container box (trak/mdia/minf/stbl) 都是 fullbox
- 但实际 MP4 文件中这些 box 可能不是 fullbox，content 从 offset+8 开始而非 offset+12
- 导致递归查找时偏移错误，永远找不到 stsd → hvcC/avcC

修复方案：
- 动态检测 fullbox：检查 offset+8 处的 version/flags 字节是否为 0
- 如果是 fullbox，content 从 offset+12 开始；否则从 offset+8 开始
- 在 containerBoxes 列表中添加 'moov'
---
 apps/web/src/pages/generate/hooks/useCanvasPlayer.ts | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts b/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
index 12933fc01..902f9d5c2 100644
--- a/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
+++ b/apps/web/src/pages/generate/hooks/useCanvasPlayer.ts
@@ -25,11 +25,15 @@ function findCodecConfig(buffer: ArrayBuffer, start: number, end: number): Array
       view.getUint8(offset + 7),
     )
 
-    // 容器 box（fullbox 多 4 字节）
-    const containerBoxes = ["trak", "mdia", "minf", "stbl"]
+    const containerBoxes = ["moov", "trak", "mdia", "minf", "stbl"]
     if (containerBoxes.includes(type)) {
-      // fullbox: size(4) + type(4) + version(1) + flags(3) = 12 bytes header
-      const contentStart = offset + 12
+      // 动态检测 fullbox：检查 offset+8 处的 version/flags 是否为 0
+      // 如果不是 fullbox，content 从 offset+8 开始；如果是 fullbox，content 从 offset+12 开始
+      const v1 = view.getUint8(offset + 8)
+      const v2 = view.getUint8(offset + 9)
+      const v3 = view.getUint8(offset + 10)
+      const isFullBox = v1 === 0 && v2 === 0 && v3 === 0
+      const contentStart = isFullBox ? offset + 12 : offset + 8
       const result = findCodecConfig(buffer, contentStart, offset + size)
       if (result) return result
     } else if (type === "stsd") {