C++ (Cpp) IMFMediaType::GetItem Examples

Example #1

File: capture.cpp Project: goussepi/lab

HRESULT SetMaxFrameRate(IMFMediaSource *pSource, DWORD dwTypeIndex)
{
  IMFPresentationDescriptor *pPD = NULL;
  IMFStreamDescriptor *pSD = NULL;
  IMFMediaTypeHandler *pHandler = NULL;
  IMFMediaType *pType = NULL;

  HRESULT hr = pSource->CreatePresentationDescriptor(&pPD);
  if (FAILED(hr))
  {
    goto done;
  }

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

  hr = pSD->GetMediaTypeHandler(&pHandler);
  if (FAILED(hr))
  {
    goto done;
  }

  hr = pHandler->GetCurrentMediaType(&pType);
  if (FAILED(hr))
  {
    goto done;
  }

  // Get the maximum frame rate for the selected capture format.

  // Note: To get the minimum frame rate, use the 
  // MF_MT_FRAME_RATE_RANGE_MIN attribute instead.

  PROPVARIANT var;
  if (SUCCEEDED(pType->GetItem(MF_MT_FRAME_RATE_RANGE_MAX, &var)))
  {
    hr = pType->SetItem(MF_MT_FRAME_RATE, var);

    PropVariantClear(&var);

    if (FAILED(hr))
    {
      goto done;
    }

    hr = pHandler->SetCurrentMediaType(pType);
  }

done:
  SafeRelease(&pPD);
  SafeRelease(&pSD);
  SafeRelease(&pHandler);
  SafeRelease(&pType);
  return hr;
}