SInt64 SFB::Audio::DSFDecoder::_SeekToFrame(SInt64 frame)
{
// Round down to nearest multiple of 8 frames
frame = (frame / 8) * 8;
// Seek to the start of the block containing frame
auto blockSizePerChannelInFrames = mFormat.ByteCountToFrameCount(mBlockByteSizePerChannel);
auto blockNumber = (size_t)frame / blockSizePerChannelInFrames;
auto blockOffset = blockNumber * mBlockByteSizePerChannel * mFormat.mChannelsPerFrame;
if(!GetInputSource().SeekToOffset(mAudioOffset + (SInt64)blockOffset)) {
LOGGER_WARNING("org.sbooth.AudioEngine.Decoder.DSF", "_SeekToFrame() failed for offset: " << mAudioOffset + (SInt64)blockOffset);
return -1;
}
if(!ReadAndDeinterleaveDSDBlock())
return -1;
// Skip to the specified frame
UInt32 framesToSkip = (UInt32)frame % blockSizePerChannelInFrames;
UInt32 framesInBuffer = (UInt32)mFormat.ByteCountToFrameCount(mBufferList->mBuffers[0].mDataByteSize);
// Copy data from the buffer to output
for(UInt32 i = 0; i < mBufferList->mNumberBuffers; ++i) {
uint8_t *dst = (uint8_t *)mBufferList->mBuffers[i].mData;
memmove(dst, dst + mFormat.FrameCountToByteCount(framesToSkip), mFormat.FrameCountToByteCount(framesInBuffer - framesToSkip));
mBufferList->mBuffers[i].mDataByteSize -= (UInt32)mFormat.FrameCountToByteCount(framesToSkip);
}
mCurrentFrame = frame;
return _GetCurrentFrame();
}
SInt64 SFB::Audio::Decoder::GetCurrentFrame() const
{
if(!IsOpen()) {
LOGGER_INFO("org.sbooth.AudioEngine.Decoder", "GetCurrentFrame() called on a Decoder that hasn't been opened");
return -1;
}
return _GetCurrentFrame();
}
SInt64 SFB::Audio::LoopableRegionDecoder::_SeekToFrame(SInt64 frame)
{
mCompletedPasses = (UInt32)(frame / mFrameCount);
mFramesReadInCurrentPass = (UInt32)(frame % mFrameCount);
mTotalFramesRead = frame;
mDecoder->SeekToFrame(mStartingFrame + mFramesReadInCurrentPass);
return _GetCurrentFrame();
}
SInt64 SFB::Audio::CoreAudioDecoder::_SeekToFrame(SInt64 frame)
{
OSStatus result = ExtAudioFileSeek(mExtAudioFile, frame);
if(noErr != result) {
LOGGER_ERR("org.sbooth.AudioEngine.Decoder.CoreAudio", "ExtAudioFileSeek failed: " << result);
return -1;
}
if(mUseM4AWorkarounds)
mCurrentFrame = frame;
return _GetCurrentFrame();
}
