使用媒体基础从h.264字节流创建MP4容器(附录B)？

Question

基本上，我有一个整洁的H.264字节流，它以I和P样本的形式存在。我可以使用MediaStreamSource和MediaElement播放这些示例，它们播放得很好。我还需要将它们保存为MP4文件，以便稍后可以使用媒体元素或VLC播放相同的内容。这就是我尝试的方法，使用Media Foundation；我从MFCreateMPEG4MediaSink创建一个IMFMediaSink；这是我的代码：

IMFMediaType *pMediaType = NULL;
IMFByteStream *pByteStream = NULL;
HRESULT hr = S_OK;
if (SUCCEEDED(hr))
{
    hr = MFCreateMediaType(&pMediaType);
}

pSeqHdr = reinterpret_cast<UINT8 *>(mSamplesQueue.SequenceHeader());
if (SUCCEEDED(hr))
{
    hr = pMediaType->SetBlob(MF_MT_MPEG_SEQUENCE_HEADER, pSeqHdr, 35);
}
UINT32 pcbBlobSize = {0};
hr = pMediaType->GetBlobSize(MF_MT_MPEG_SEQUENCE_HEADER, &pcbBlobSize);

/*if (SUCCEEDED(hr))
{
    hr = pMediaType->SetUINT32(MF_MPEG4SINK_SPSPPS_PASSTHROUGH, TRUE);
}*/
if (SUCCEEDED(hr))
{
    hr = pMediaType->SetGUID(MF_MT_MAJOR_TYPE, MFMediaType_Video);
}
if (SUCCEEDED(hr))
{
    hr = pMediaType->SetGUID(MF_MT_SUBTYPE, VIDEO_INPUT_FORMAT);
}
if (SUCCEEDED(hr))
{
    hr = MFSetAttributeRatio(pMediaType, MF_MT_FRAME_RATE, VIDEO_FPS, 1);
}
if (SUCCEEDED(hr))
{
    hr = pMediaType->SetUINT32(MF_MT_AVG_BITRATE, VIDEO_BIT_RATE);
}
if (SUCCEEDED(hr))
{
    hr = pMediaType->SetUINT32(MF_MT_INTERLACE_MODE, MFVideoInterlace_Progressive);
}
if (SUCCEEDED(hr))
{
    hr = MFSetAttributeSize(pMediaType, MF_MT_FRAME_SIZE, VIDEO_WIDTH, VIDEO_HEIGHT);
}
if (SUCCEEDED(hr))
{
    // Pixel aspect ratio
    hr = MFSetAttributeRatio(pMediaType, MF_MT_PIXEL_ASPECT_RATIO, 1, 1);
}
if (SUCCEEDED(hr))
{
    hr = MFCreateFile(
        MF_ACCESSMODE_READWRITE,
        MF_OPENMODE_DELETE_IF_EXIST,
        MF_FILEFLAGS_NONE,
        L"output1.mp4",
        &pByteStream);
}
if (SUCCEEDED(hr))
{
    hr = MFCreateMPEG4MediaSink(
        pByteStream,
        pMediaType,
        NULL,
        &pMediaSink);
}

然后我使用MFCreateSinkWriterFromMediaSink从这个媒体接收器创建一个IMFSinkWriter；这是我的代码：

if (SUCCEEDED(hr))
{
    hr = MFCreateSinkWriterFromMediaSink(pMediaSink, NULL, &pSinkWriter);
}
// Tell the sink writer to start accepting data.
if (SUCCEEDED(hr))
{
    hr = pSinkWriter->BeginWriting();
}

if (SUCCEEDED(hr))
{
    pSinkWriter->AddRef();
}

然后我用IMFSinkWriter::WriteSample(0，IMFSample )将每个样本写到接收器写入器；这是我的代码:IMFSample *pSample = NULL；IMFMediaBuffer *pBuffer = NULL；

const DWORD cbBuffer = mSamplesQueue.GetNextSampleSize();
UINT32 isIDR = mSamplesQueue.GetNextSampleIsIDR();
BYTE *pData = NULL;

// Create a new memory buffer.
HRESULT hr = MFCreateMemoryBuffer(cbBuffer, &pBuffer);

// Lock the buffer and copy the video frame to the buffer.
if (SUCCEEDED(hr))
{
    DWORD buffLen = cbBuffer;
    hr = pBuffer->Lock(&pData, &buffLen, 0);
}
if (SUCCEEDED(hr))
{
    hr = mSamplesQueue.Dequeu(&pData);
}
if (pBuffer)
{
    pBuffer->Unlock();
}

// Set the data length of the buffer.
if (SUCCEEDED(hr))
{
    hr = pBuffer->SetCurrentLength(cbBuffer);
}

// Create a media sample and add the buffer to the sample.
if (SUCCEEDED(hr))
{
    hr = MFCreateSample(&pSample);
}
if (SUCCEEDED(hr))
{
    hr = pSample->AddBuffer(pBuffer);
}

// Set the time stamp and the duration.
if (SUCCEEDED(hr))
{
    hr = pSample->SetSampleTime(rtStart);
}
if (SUCCEEDED(hr))
{
    hr = pSample->SetSampleDuration(rtDuration);
}
if (SUCCEEDED(hr))
{
    hr = pSample->SetUINT32(MFSampleExtension_CleanPoint, isIDR);
}
//pSample->
// Send the sample to the Sink Writer.
if (SUCCEEDED(hr))
{
    hr = pSinkWriter->WriteSample(0, pSample);
}

SafeRelease(&pSample);
SafeRelease(&pBuffer);

样本的编写是从我拥有的每个样本中调用的迭代代码(我正在用1k的I和P样本进行测试)。现在，当我调用IMFSinkWriter::Finalize()时，它告诉我"0xc00d4a45 : Sink无法创建有效的输出文件，因为所需的头没有提供给sink“。它确实创建了一个大小非常有效的MP4文件(对于我的1k示例，大小为4.6MB)。如果它要求MF_MT_MPEG_SEQUENCE_HEADER，那么我用IMFMediaType::SetBlob(MF_MT_MPEG_SEQUENCE_HEADER，This is the link to the trace from MFTrace.，UINT32设置它们)我用Elecard视频格式分析器检查了文件，但标题似乎不完整。我是否可以得到一些帮助，找出我遗漏了什么，或者是否有更好的/其他方法来实现我想要实现的目标？谢谢!

Answer 1

对我来说，问题在于MF_MT_MPEG_SEQUENCE_HEADER blob的格式。

与dwSequenceHeader和H.264上的MSDN文档相反，SPS和PPS应该预先加上起始码(0x00,0x00,0x01)，而不是2字节长度字段。

http://msdn.microsoft.com/en-us/library/dd757808%28VS.85%29.aspx

Answer 2

不确定，但是，不应该是：

hr = pMediaType->SetGUID(MF_MT_SUBTYPE, VIDEO_ENCODING_FORMAT);

而不是：

hr = pMediaType->SetGUID(MF_MT_SUBTYPE, VIDEO_INPUT_FORMAT);