SINT SoundSourceMediaFoundation::readSampleFrames(
SINT numberOfFrames, CSAMPLE* sampleBuffer) {
SINT numberOfFramesRemaining = numberOfFrames;
CSAMPLE* pSampleBuffer = sampleBuffer;
while (numberOfFramesRemaining > 0) {
SampleBuffer::ReadableChunk readableChunk(
m_sampleBuffer.readFromHead(
frames2samples(numberOfFramesRemaining)));
DEBUG_ASSERT(readableChunk.size()
<= frames2samples(numberOfFramesRemaining));
if (readableChunk.size() > 0) {
DEBUG_ASSERT(m_currentFrameIndex < getMaxFrameIndex());
if (sampleBuffer != nullptr) {
SampleUtil::copy(
pSampleBuffer,
readableChunk.data(),
readableChunk.size());
pSampleBuffer += readableChunk.size();
}
m_currentFrameIndex += samples2frames(readableChunk.size());
numberOfFramesRemaining -= samples2frames(readableChunk.size());
}
if (numberOfFramesRemaining == 0) {
break; // finished reading
}
// No more decoded sample frames available
DEBUG_ASSERT(m_sampleBuffer.isEmpty());
if (m_pSourceReader == nullptr) {
break; // abort if reader is dead
}
DWORD dwFlags = 0;
LONGLONG streamPos = 0;
IMFSample* pSample = nullptr;
HRESULT hrReadSample =
m_pSourceReader->ReadSample(
kStreamIndex, // [in] DWORD dwStreamIndex,
0, // [in] DWORD dwControlFlags,
nullptr, // [out] DWORD *pdwActualStreamIndex,
&dwFlags, // [out] DWORD *pdwStreamFlags,
&streamPos, // [out] LONGLONG *pllTimestamp,
&pSample); // [out] IMFSample **ppSample
if (FAILED(hrReadSample)) {
qWarning() << kLogPreamble
<< "IMFSourceReader::ReadSample() failed"
<< hrReadSample
<< "-> abort decoding";
DEBUG_ASSERT(pSample == nullptr);
break; // abort
}
if (dwFlags & MF_SOURCE_READERF_ERROR) {
qWarning() << kLogPreamble
<< "IMFSourceReader::ReadSample()"
<< "detected stream errors"
<< "(MF_SOURCE_READERF_ERROR)"
<< "-> abort and stop decoding";
DEBUG_ASSERT(pSample == nullptr);
safeRelease(&m_pSourceReader); // kill the reader
break; // abort
} else if (dwFlags & MF_SOURCE_READERF_ENDOFSTREAM) {
DEBUG_ASSERT(pSample == nullptr);
break; // finished reading
} else if (dwFlags & MF_SOURCE_READERF_CURRENTMEDIATYPECHANGED) {
qWarning() << kLogPreamble
<< "IMFSourceReader::ReadSample()"
<< "detected that the media type has changed"
<< "(MF_SOURCE_READERF_CURRENTMEDIATYPECHANGED)"
<< "-> abort decoding";
DEBUG_ASSERT(pSample == nullptr);
break; // abort
}
DEBUG_ASSERT(pSample != nullptr);
SINT readerFrameIndex = m_streamUnitConverter.toFrameIndex(streamPos);
DEBUG_ASSERT(
(m_currentFrameIndex == getMaxFrameIndex()) || // unknown position after seeking
(m_currentFrameIndex == readerFrameIndex));
m_currentFrameIndex = readerFrameIndex;
DWORD dwSampleBufferCount = 0;
HRESULT hrGetBufferCount =
pSample->GetBufferCount(&dwSampleBufferCount);
if (FAILED(hrGetBufferCount)) {
qWarning() << kLogPreamble
<< "IMFSample::GetBufferCount() failed"
<< hrGetBufferCount
<< "-> abort decoding";
safeRelease(&pSample);
break; // abort
}
DWORD dwSampleTotalLengthInBytes = 0;
HRESULT hrGetTotalLength = pSample->GetTotalLength(&dwSampleTotalLengthInBytes);
if (FAILED(hrGetTotalLength)) {
qWarning() << kLogPreamble
<< "IMFSample::GetTotalLength() failed"
<< hrGetTotalLength
<< "-> abort decoding";
safeRelease(&pSample);
break; // abort
}
// Enlarge temporary buffer (if necessary)
DEBUG_ASSERT((dwSampleTotalLengthInBytes % kBytesPerSample) == 0);
SINT numberOfSamplesToBuffer =
dwSampleTotalLengthInBytes / kBytesPerSample;
SINT sampleBufferCapacity = m_sampleBuffer.getCapacity();
DEBUG_ASSERT(sampleBufferCapacity > 0);
while (sampleBufferCapacity < numberOfSamplesToBuffer) {
sampleBufferCapacity *= 2;
}
if (m_sampleBuffer.getCapacity() < sampleBufferCapacity) {
qDebug() << kLogPreamble
<< "Enlarging sample buffer capacity"
<< m_sampleBuffer.getCapacity()
<< "->"
<< sampleBufferCapacity;
m_sampleBuffer.resetCapacity(sampleBufferCapacity);
}
DWORD dwSampleBufferIndex = 0;
while (dwSampleBufferIndex < dwSampleBufferCount) {
IMFMediaBuffer* pMediaBuffer = nullptr;
HRESULT hrGetBufferByIndex = pSample->GetBufferByIndex(dwSampleBufferIndex, &pMediaBuffer);
if (FAILED(hrGetBufferByIndex)) {
qWarning() << kLogPreamble
<< "IMFSample::GetBufferByIndex() failed"
<< hrGetBufferByIndex
<< "-> abort decoding";
DEBUG_ASSERT(pMediaBuffer == nullptr);
break; // prematurely exit buffer loop
}
CSAMPLE* pLockedSampleBuffer = nullptr;
DWORD lockedSampleBufferLengthInBytes = 0;
HRESULT hrLock = pMediaBuffer->Lock(
reinterpret_cast<quint8**>(&pLockedSampleBuffer),
nullptr,
&lockedSampleBufferLengthInBytes);
if (FAILED(hrLock)) {
qWarning() << kLogPreamble
<< "IMFMediaBuffer::Lock() failed"
<< hrLock
<< "-> abort decoding";
safeRelease(&pMediaBuffer);
break; // prematurely exit buffer loop
}
DEBUG_ASSERT((lockedSampleBufferLengthInBytes % sizeof(pLockedSampleBuffer[0])) == 0);
SINT lockedSampleBufferCount =
lockedSampleBufferLengthInBytes / sizeof(pLockedSampleBuffer[0]);
SINT copySamplesCount = std::min(
frames2samples(numberOfFramesRemaining),
lockedSampleBufferCount);
if (copySamplesCount > 0) {
// Copy samples directly into output buffer if possible
if (pSampleBuffer != nullptr) {
SampleUtil::copy(
pSampleBuffer,
pLockedSampleBuffer,
copySamplesCount);
pSampleBuffer += copySamplesCount;
}
pLockedSampleBuffer += copySamplesCount;
lockedSampleBufferCount -= copySamplesCount;
m_currentFrameIndex += samples2frames(copySamplesCount);
numberOfFramesRemaining -= samples2frames(copySamplesCount);
}
// Buffer the remaining samples
SampleBuffer::WritableChunk writableChunk(
m_sampleBuffer.writeToTail(lockedSampleBufferCount));
// The required capacity has been calculated in advance (see above)
DEBUG_ASSERT(writableChunk.size() == lockedSampleBufferCount);
SampleUtil::copy(
writableChunk.data(),
pLockedSampleBuffer,
writableChunk.size());
HRESULT hrUnlock = pMediaBuffer->Unlock();
VERIFY_OR_DEBUG_ASSERT(SUCCEEDED(hrUnlock)) {
qWarning() << kLogPreamble
<< "IMFMediaBuffer::Unlock() failed"
<< hrUnlock;
// ignore and continue
}
safeRelease(&pMediaBuffer);
++dwSampleBufferIndex;
}
safeRelease(&pSample);
if (dwSampleBufferIndex < dwSampleBufferCount) {
// Failed to read data from all buffers -> kill the reader
qWarning() << kLogPreamble
<< "Failed to read all buffered samples"
<< "-> abort and stop decoding";
safeRelease(&m_pSourceReader);
break; // abort
}
}
return numberOfFrames - numberOfFramesRemaining;
}
