void SoundSourceFLAC::flacMetadata(const FLAC__StreamMetadata* metadata) {
// https://xiph.org/flac/api/group__flac__stream__decoder.html#ga43e2329c15731c002ac4182a47990f85
// "...one STREAMINFO block, followed by zero or more other metadata blocks."
// "...by default the decoder only calls the metadata callback for the STREAMINFO block..."
// "...always before the first audio frame (i.e. write callback)."
switch (metadata->type) {
case FLAC__METADATA_TYPE_STREAMINFO:
{
const SINT channelCount = metadata->data.stream_info.channels;
if (isValidChannelCount(channelCount)) {
if (hasChannelCount()) {
// already set before -> check for consistency
if (getChannelCount() != channelCount) {
qWarning() << "Unexpected channel count:"
<< channelCount << " <> " << getChannelCount();
}
} else {
// not set before
setChannelCount(channelCount);
}
} else {
qWarning() << "Invalid channel count:"
<< channelCount;
}
const SINT samplingRate = metadata->data.stream_info.sample_rate;
if (isValidSamplingRate(samplingRate)) {
if (hasSamplingRate()) {
// already set before -> check for consistency
if (getSamplingRate() != samplingRate) {
qWarning() << "Unexpected sampling rate:"
<< samplingRate << " <> " << getSamplingRate();
}
} else {
// not set before
setSamplingRate(samplingRate);
}
} else {
qWarning() << "Invalid sampling rate:"
<< samplingRate;
}
const SINT frameCount = metadata->data.stream_info.total_samples;
DEBUG_ASSERT(isValidFrameCount(frameCount));
if (isEmpty()) {
// not set before
setFrameCount(frameCount);
} else {
// already set before -> check for consistency
if (getFrameCount() != frameCount) {
qWarning() << "Unexpected frame count:"
<< frameCount << " <> " << getFrameCount();
}
}
const unsigned bitsPerSample = metadata->data.stream_info.bits_per_sample;
DEBUG_ASSERT(kBitsPerSampleDefault != bitsPerSample);
if (kBitsPerSampleDefault == m_bitsPerSample) {
// not set before
m_bitsPerSample = bitsPerSample;
m_sampleScaleFactor = CSAMPLE_PEAK
/ CSAMPLE(FLAC__int32(1) << bitsPerSample);
} else {
// already set before -> check for consistency
if (bitsPerSample != m_bitsPerSample) {
qWarning() << "Unexpected bits per sample:"
<< bitsPerSample << " <> " << m_bitsPerSample;
}
}
m_maxBlocksize = metadata->data.stream_info.max_blocksize;
if (0 >= m_maxBlocksize) {
qWarning() << "Invalid max. blocksize" << m_maxBlocksize;
}
const SINT sampleBufferCapacity =
m_maxBlocksize * getChannelCount();
m_sampleBuffer.resetCapacity(sampleBufferCapacity);
break;
}
default:
// Ignore all other metadata types
break;
}
}
void AudioSource::setFrameCount(SINT frameCount) {
DEBUG_ASSERT(isValidFrameCount(frameCount));
m_frameCount = frameCount;
}
