在媒体会话中应用 MFT（灰度样本）

Question

我正在使用以下 MSDN 示例代码（媒体基础）

1. 音频/视频播放
   • https://msdn.microsoft.com/en-us/library/windows/desktop/dd317914(v=vs.85).aspx
2. 创建变换节点
   • https://msdn.microsoft.com/en-us/library/windows/desktop/bb250384(v=vs.85).aspx
3. 将解码器添加到拓扑
   • https://msdn.microsoft.com/en-us/library/windows/desktop/bb250371(v=vs.85).aspx

我想将 MFT 应用于基于媒体会话的播放 MFT_灰度样本 - https://msdn.microsoft.com/en-us/library/windows/desktop/bb970487(v=vs.85).aspx

.dll 已注册并与 TopoEdit 配合良好。

基于上面的示例，我只添加了拓扑链接。 但它不起作用。

这是我添加的内容。

HRESULT AddBranchToPartialTopology(
IMFTopology *pTopology,         // Topology.
IMFMediaSource *pSource,        // Media source.
IMFPresentationDescriptor *pPD, // Presentation descriptor.
DWORD iStream,                  // Stream index.
HWND hVideoWnd)                 // 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;
    }

    if (fSelected)
    {
        // Create the media sink activation object.
        hr = CreateMediaSinkActivate(pSD, hVideoWnd, &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, 0, &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_GrayscaleMFT, &pMFTNode);

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

                // Connect the decoder node to the output node.
                if (SUCCEEDED(hr))
                {
                    hr = pDecoderNode->ConnectOutput(0, pMFTNode, 0);
                }

                if (SUCCEEDED(hr))
                {
                    hr = pMFTNode->ConnectOutput(0, pOutputNode, 0);
                }
            }
        }
        // Mark this branch as not requiring a decoder.
        if (SUCCEEDED(hr))
        {
            hr = pOutputNode->SetUINT32(
                MF_TOPONODE_CONNECT_METHOD,
                MF_CONNECT_ALLOW_CONVERTER
                );
        }

        if (SUCCEEDED(hr))
        {
            hr = pDecoderNode->SetUINT32(
                MF_TOPONODE_CONNECT_METHOD,
                MF_CONNECT_ALLOW_CONVERTER
                );
        }

        if (SUCCEEDED(hr))
        {
            hr = pMFTNode->SetUINT32(
                MF_TOPONODE_CONNECT_METHOD,
                MF_CONNECT_ALLOW_CONVERTER
                );
        }
    }
    // else: If not selected, don't add the branch. 
done:
    SafeRelease(&pSD);
    SafeRelease(&pSinkActivate);
    SafeRelease(&pSourceNode);
    SafeRelease(&pOutputNode);
    SafeRelease(&pDecoderNode);
    SafeRelease(&pMFTNode);
    return hr;
}    

Answer 1

我觉得自己像个傻瓜。

MFT_Grayscale 是仅转换视频流。

不应连接音频流。

如下……

if (MFMediaType_Audio == guidMajorType)
{
    pSourceNode->ConnectOutput(0, pDecoderNode, 0);
    pDecoderNode->ConnectOutput(0, pOutputNode, 0);
}
else if (MFMediaType_Video == guidMajorType)
{
    pSourceNode->ConnectOutput(0, pDecoderNode, 0);
    pDecoderNode->ConnectOutput(0, pMFTNode, 0);
    pMFTNode->ConnectOutput(0, pOutputNode, 0);
}