bool SoundSourceMediaFoundation::readProperties()
{
PROPVARIANT prop;
HRESULT hr = S_OK;
//Get the duration, provided as a 64-bit integer of 100-nanosecond units
hr = m_pReader->GetPresentationAttribute(MF_SOURCE_READER_MEDIASOURCE,
MF_PD_DURATION, &prop);
if (FAILED(hr)) {
qWarning() << "SSMF: error getting duration";
return false;
}
// QuadPart isn't available on compilers that don't support _int64. Visual
// Studio 6.0 introduced the type in 1998, so I think we're safe here
// -bkgood
m_iDuration = secondsFromMF(prop.hVal.QuadPart);
m_mfDuration = prop.hVal.QuadPart;
qDebug() << "SSMF: Duration:" << m_iDuration;
PropVariantClear(&prop);
// presentation attribute MF_PD_AUDIO_ENCODING_BITRATE only exists for
// presentation descriptors, one of which MFSourceReader is not.
// Therefore, we calculate it ourselves.
m_iBitrate = kBitsPerSample * kSampleRate * kNumChannels;
return true;
}
inline unsigned long SoundSourceMediaFoundation::length()
{
unsigned long len(secondsFromMF(m_mfDuration) * kSampleRate * kNumChannels);
return len % kNumChannels == 0 ? len : len + 1;
}
inline int AudioDecoderMediaFoundation::numSamples()
{
int len(secondsFromMF(m_mfDuration) * m_iSampleRate * m_iChannels);
return len % m_iChannels == 0 ? len : len + 1;
}
