Question

目的是在一个屏幕上显示两个视频流。

我使用以下MSDN示例代码。和堆栈

音频/视频播放

https://msdn.microsoft.com/en-us/library/windows/desktop/dd317914(v=vs.85).aspx

创建转换节点

https://msdn.microsoft.com/en-us/library/windows/desktop/bb250384(v=vs.85).aspx

将解码器添加到拓扑

https://msdn.microsoft.com/en-us/library/windows/desktop/bb250371(v=vs.85).aspx

堆

Add two media sources in topology and display mix video - Windows Media Foundation

我的媒体资源在一个文件中有两个视频流。而且我没有通过MFCreateAggregateSource进行IMFCollection。但是没有输出。

我制作媒体两个媒体下沉。它的工作原理。但是交替显示没有索引值。

我认为这是一个问题，IMFTransForm :: AddInputStreams，getStreamLimits ......没有被调用。

我不知道该怎么做。

听到的是代码：

HRESULT CreatePlaybackTopology( .... )
{
    ....
    hr = MFCreateVideoRendererActivate(hVideoWnd, &pVideoRendererActivate);
    // For each stream, create the topology nodes and add them to the topology.
    for (DWORD i = 0; i < cSourceStreams; i++)
    {
        hr = AddBranchToPartialTopology(pTopology, pSource, pPD, i, pVideoRendererActivate);
        if (FAILED(hr))
        {
            goto done;
        }
    }
....
}

AddBranchPartialTopilogy方法。

HRESULT AddBranchToPartialTopology(
IMFTopology *pTopology,         // Topology.
IMFMediaSource *pSource,        // Media source.
IMFPresentationDescriptor *pPD, // Presentation descriptor.
DWORD iStream,                  // Stream index.
IMFActivate* pVideoRendererActivate)                 // Window for video playback.
{
    IMFStreamDescriptor *pSD = NULL;
    IMFActivate         *pSinkActivate = NULL;
    IMFTopologyNode     *pSourceNode = NULL;
    IMFTopologyNode     *pOutputNode = NULL;
    IMFTopologyNode     *pDecoderNode = NULL;
    IMFTopologyNode     *pMFTNode = NULL;

    BOOL fSelected = FALSE;
CLSID clsidDecoder = GUID_NULL;

HRESULT hr = pPD->GetStreamDescriptorByIndex(iStream, &fSelected, &pSD);
if (FAILED(hr))
{
    goto done;
}

DWORD iStreamID = 0;

if (fSelected)
{
    // Create the media sink activation object.
    hr = CreateMediaSinkActivate(pSD, iStreamID, pVideoRendererActivate, &pSinkActivate);
    if (FAILED(hr))
    {
        goto done;
    }

    // Add a source node for this stream.
    hr = AddSourceNode(pTopology, pSource, pPD, pSD, &pSourceNode);
    if (FAILED(hr))
    {
        goto done;
    }

    // Create the output node for the renderer.
    hr = AddOutputNode(pTopology, pSinkActivate, iStreamID, &pOutputNode);
    if (FAILED(hr))
    {
        goto done;
    }

    // Find a decoder.
    if (SUCCEEDED(hr))
    {
        hr = FindDecoderForStream(pSD, &clsidDecoder);
    }

    if (SUCCEEDED(hr))
    {
        if (clsidDecoder == GUID_NULL)
        {
            // No decoder is required. 
            // Connect the source node to the output node.
            hr = pSourceNode->ConnectOutput(0, pOutputNode, 0);
        }
        else
        {
            // Add a decoder node.
            hr = AddTransformNode(pTopology, clsidDecoder, &pDecoderNode);
            hr = AddTransformNode(pTopology, CLSID_TopviewMFT, &pMFTNode);
            // Connect the source node to the decoder node.
            if (SUCCEEDED(hr))
            {
                hr = pSourceNode->ConnectOutput(0, pDecoderNode, 0);
            }

            if (SUCCEEDED(hr))
            {
                hr = pDecoderNode->ConnectOutput(0, pMFTNode, 0);
            }

            if (SUCCEEDED(hr))
            {
                hr = pMFTNode->ConnectOutput(0, pOutputNode, 0);
            }
        }
    }
}
// else: If not selected, don't add the branch. 

done:
    SafeRelease(&pSD);
    SafeRelease(&pSinkActivate);
    SafeRelease(&pSourceNode);
    SafeRelease(&pOutputNode);
    SafeRelease(&pDecoderNode);
    SafeRelease(&pMFTNode);

    return hr;
}

CreateMediaSinkActivate方法。

DWORD globalVideoIndex = 0;
HRESULT CreateMediaSinkActivate(
    IMFStreamDescriptor *pSourceSD,     // Pointer to the stream descriptor.
    DWORD& iStreamID,
    IMFActivate* pVideoRendererActivate,                  // Handle to the video clipping window.
    IMFActivate **ppActivate
)
{
    IMFMediaTypeHandler *pHandler = NULL;
    IMFActivate *pActivate = NULL;

    // Get the media type handler for the stream.
    HRESULT hr = pSourceSD->GetMediaTypeHandler(&pHandler);
    if (FAILED(hr))
    {
        goto done;
    }

    // Get the major media type.
    GUID guidMajorType;
    hr = pHandler->GetMajorType(&guidMajorType);
    if (FAILED(hr))
    {
        goto done;
    }

    // Create an IMFActivate object for the renderer, based on the media type.
    if (MFMediaType_Audio == guidMajorType)
    {
        // Create the audio renderer.
        hr = MFCreateAudioRendererActivate(&pActivate);
    }
    else if (MFMediaType_Video == guidMajorType)
    {
        // Create the video renderer.
//        hr = MFCreateVideoRendererActivate(hVideoWindow, &pActivate);
    hr = pVideoRendererActivate->QueryInterface(IID_PPV_ARGS(&pActivate));
    iStreamID = globalVideoIndex++;
    }
    else
    {
        // Unknown stream type. 
        hr = E_FAIL;
        // Optionally, you could deselect this stream instead of failing.
    }
    if (FAILED(hr))
    {
        goto done;
    }

    // Return IMFActivate pointer to caller.
    *ppActivate = pActivate;
    (*ppActivate)->AddRef();

    done:
        SafeRelease(&pHandler);
        SafeRelease(&pActivate);

        return hr;
}

MFT .h

interface IMFVideoMixerControl;

class CTopview : BaseObject, 
    public IMFVideoDeviceID,
    public IMFGetService,
    public IMFTopologyServiceLookupClient,
    public IMFTransform,
//  public IMFVideoMixerControl,
    public IMFAttributes
{
public:
    static HRESULT CreateInstance(IUnknown *pUnkOuter, REFIID iid, void **ppSource);

    // IUnknown
    STDMETHODIMP QueryInterface(REFIID iid, void** ppv);
    STDMETHODIMP_(ULONG) AddRef();
    STDMETHODIMP_(ULONG) Release();
....

两个视频流到一个屏幕 - 媒体基金会

0 个答案: