使用FFMpeg iOS解码摄像头视频帧时出现错误

Question

我有一个应用程序，在其中解码来自IP摄像机的视频帧，但是avcodec.h中的方法avcodec_decode_video2(m_pCodecCtx, m_pFrame, &consumed_bytes, &avpkt);会生成bad_access错误，我无法弄清楚出了什么问题。

这个应用程序在旧版本的FFMpeg库中运行良好，但由于苹果政策要求支持arm64才能发布应用程序，因此我更新了库以支持arm64，之后出现了这个问题。

以下是屏幕截图：

当bad_access应用程序生成以下日志时：

[h264 @ 0x1071400] sps_id 12 out of range
[h264 @ 0x1071400] pps_id 417 out of range
[h264 @ 0x1071400] sps_id 3 out of range
[h264 @ 0x1071400] sps_id 32 out of range
[h264 @ 0x1071400] sps_id 6 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 32 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 3 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 32 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 32 out of range
[h264 @ 0x1071400] sps_id 3 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] pps_id 418 out of range
[h264 @ 0x1071400] Partitioned H.264 support is incomplete
[h264 @ 0x1071400] sps_id 6 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 1 out of range
[h264 @ 0x1071400] non-existing PPS 3 referenced
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] slice type 10 too large at 0 0
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] non-existing PPS 2 referenced
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] slice type 29 too large at 0 0
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] sps_id 2 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] sps_id 0 out of range
[h264 @ 0x1071400] slice type 32 too large at 0 0
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] slice type 32 too large at 0 0
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] slice type 32 too large at 0 0
[h264 @ 0x1071400] decode_slice_header error
[h264 @ 0x1071400] slice type 32 too large at 0 0

完整的错误日志: https://drive.google.com/file/d/0B-Nh7ci6wLX0OVlxaXV4aGpJems/view?usp=sharing

崩溃日志: http://crashes.to/s/6765d63b540

注：如果您需要其他任何东西，请在评论中提出。

- Irfan Gul

---

那个截图似乎与崩溃日志不符。崩溃日志看起来像是解除空指针引用的问题。另外，了解参数值将会很有用。 - trojanfoe

你想看哪些参数？告诉我你需要什么。 - Irfan Gul

传递给该方法的参数 - trojanfoe

请等一下，让我更新崩溃日志和参数。 - Irfan Gul

@trojanfoe 更新了我的问题。 - Irfan Gul

Answer 1

我解决了我的问题，问题出在已弃用的方法avcodec_alloc_frame()上。

我在构造函数中使用了以下代码：

    m_pCodecCtx = avcodec_alloc_context3(m_pCodec);
    if(m_pCodecCtx == NULL)
    {
        NSLog(@"if(pCodecCtx == NULL)\n");
        return ;
    }  
   [g_Lock lock];
    //¥Úø™codec°£»Áπ˚¥Úø™≥…𶵃ª∞£¨∑÷≈‰AVFrame£     
    if(avcodec_open2(m_pCodecCtx, m_pCodec, NULL) >= 0)     
    {     
        m_pFrame = avcodec_alloc_frame();   /* Allocate video frame   */

    }
    [g_Lock unlock];

最终我更新了头文件，然后收到了关于方法 avcodec_alloc_frame() 废弃的警告，所以我将其更新为 av_frame_alloc()，结果完美无缺！

- Irfan Gul