Implement the following class:
class CGetSamples WrlSealed
: public RuntimeClass<
RuntimeClassFlags< Microsoft::WRL::RuntimeClassType::WinRtClassicComMix >,
ABI::Windows::Media::IMediaExtension,
IMFMediaSink,
IMFClockStateSink>
{
...
};
Sample data will be delivered to the custom IMFStreamSink you write which is part of the IMFMediaSink. The IMFSample data will be passed to IMFStreamSink::ProcessSample method.
Then create an instance of this to pass to the StartRecordToCustomSinkAsync method:
IInspectable* pInstpectable = nullptr;
HRESULT hr = MakeAndInitialize<CGetSamples>(&pInstpectable);
IMediaExtension^ me = reinterpret_cast<IMediaExtension^>(pInstpectable);
MediaEncodingProfile^ mep = MediaEncodingProfile::CreateMp4(VideoEncodingQuality::Vga);
// m_MC is an instance of MediaCapture
m_MC->StartRecordToCustomSinkAsync(mep, me);
The samples will not come out as RGB, they will likely be YUY2 or some similar format. Since you can't set the IMFMediaType on the capture device or the source reader in order to get MF to do the conversion automatically, you are left to do it
yourself. To get RGB data you will have to create an ID3D11VideoProcessor with input views matching the YUY2 format and an output view that is RBG. Then call the ID3D11VideoContext::VideoProcessorBlt
method.
Get the ID3D11Resource interface by QIing for it off of the IMFMediaBuffer on each sample. From this you can get the ID3D11Device. QI for the ID3D11VideoDevice, then create the ID3D11VideoProcessorEnumerator, then the ID3D11VideoProcessor.
An ID3D11Texture2D with the RGB will have to be created as the destination and the ID3D11VideoProcessorOutputView wrapping it. Create a ID3D11VideoProcessorInputView on the sample buffer. Then Blit the sample to the surface using the video context
and video processor.
