I use the applicationloopbackaudio-sample to record system audio, it works fine. However, the capture format is hard coded:
// The app can also call m_AudioClient->GetMixFormat instead to get the capture format.
// 16 - bit PCM format.
m_CaptureFormat.wFormatTag = WAVE_FORMAT_PCM;
m_CaptureFormat.nChannels = 2;
m_CaptureFormat.nSamplesPerSec = 44100;
m_CaptureFormat.wBitsPerSample = 16;
m_CaptureFormat.nBlockAlign = m_CaptureFormat.nChannels * m_CaptureFormat.wBitsPerSample / 8;
m_CaptureFormat.nAvgBytesPerSec = m_CaptureFormat.nSamplesPerSec * m_CaptureFormat.nBlockAlign;
according to the comment, I can use m_AudioClient->GetMixFormat to get the capture format, but it failed with error code: E_NOTIMPL
WAVEFORMATEX* pWfxOut = NULL;
HRESULT hr = m_AudioClient->GetMixFormat(&pWfxOut);
// hr is E_NOTIMPL, failed to GetMixFormat
I'd like to know:
- why does this happen?
- how should I get the valid capture format supported by System? Many thanks.
Environment: Visual Studio 2019, Windows SDK20348
