Rendering Audio Samples with Media Foundation

Hello,

I am wanting to render out audio from a micraphone via an IMFSample in Media Foundation, I have spent days on trying to figure out how to do this, I have looked at the MSDN docs for media foundation and they are not that helpful.

Currently I am capturing the audio device with MF_DEVSOURCE_ATTRIBUTE_SOURCE_TYPE_AUDCAP_ENDPOINT_ID then I am creating an IMFSourceReader via the IMFActivate of the capture object, I am reading the samples asynchronously in OnReadSample via the IMFSourceReaderCallback.

I then enumerate an audio output device via:

hr = pEnum->EnumAudioEndpoints(eRender, eMultimedia, &pDevices);

and create an audio renderer with the following:

hr = MFCreateAudioRenderer(pAttributes, &m_pAudioSink);

I never hear anything at the endpoint even though OnReadSample is generating data.

I also tried the following:

IMFActivate* pActivate = MadNull;
    hr = MFCreateAudioRendererActivate( &pActivate );

    hr = MFCreateTopology( &m_pTopology );

    IMFPresentationDescriptor* pPresDesc = MadNull;
    hr = m_pMediaSource->CreatePresentationDescriptor( &pPresDesc );
    
    BOOL bSelected = FALSE;
    IMFStreamDescriptor* pStreamDesc = MadNull;
    hr = pPresDesc->GetStreamDescriptorByIndex( 0, &bSelected, &pStreamDesc );

    IMFTopologyNode* pSourceNode = MadNull;
    IMFTopologyNode* pOutputNode = MadNull;

    hr = MFCreateTopologyNode( MF_TOPOLOGY_SOURCESTREAM_NODE, &pSourceNode );

    hr = pSourceNode->SetUnknown( MF_TOPONODE_SOURCE, m_pMediaSource );

    hr = pSourceNode->SetUnknown( MF_TOPONODE_PRESENTATION_DESCRIPTOR, pPresDesc );
    hr = pSourceNode->SetUnknown( MF_TOPONODE_STREAM_DESCRIPTOR, pStreamDesc );

    DWORD stream_id;
    GUID major_type = GUID_NULL;
    IMFMediaTypeHandler* pHdlr = MadNull;
    hr = pStreamDesc->GetStreamIdentifier( &stream_id );
    hr = pStreamDesc->GetMediaTypeHandler( &pHdlr );
    hr = pHdlr->GetMajorType( &major_type );

    hr = MFCreateTopologyNode( MF_TOPOLOGY_OUTPUT_NODE, &pOutputNode );
    

    hr = pOutputNode->SetObject( pActivate );

    hr = m_pTopology->AddNode( pSourceNode );
    hr = m_pTopology->AddNode( pOutputNode );

    hr = pSourceNode->ConnectOutput( 0, pOutputNode, 0 );

    hr = pActivate->SetString( MF_AUDIO_RENDERER_ATTRIBUTE_ENDPOINT_ID, wstrID );

    if( SUCCEEDED( hr ) )
    {
        hr = MFCreateMediaSession( MadNull, &m_pSession );

        hr = m_pSession->SetTopology( 0, m_pTopology );
        hr = m_pSession->Start(&GUID_NULL, MadNull);
    }

I still got nothing from that......

All I want to do is send the samples generated from the sourcereader to the audio output device.

Cheers