public override int ReadSample(byte[] buffer, int start, int count)
{
MultiplexedFrame fr = new MultiplexedFrame();
fr.BitsInSample = streamInfo.BitsPerSample;
fr.NumChannels = streamInfo.NumberOfChannels;
fr.SampleCount = 0;
fr.BitOffset = 0;
fr.BufferUsed = 0;
fr.Buffer = new byte[fr.NumChannels,count * (fr.BitsInSample / 8 + 1)];
int sampleCount = 0;
int samplesLeft = count;
try
{
for (; ; )
{
if(!frameDecoded)
{
currentFrame.Decode(physicalStream,flacStreamInfo);
frameDecoded = true;
}
int samplesToRead = 0;
if((ulong)samplesLeft > currentFrame.LastSampleNumber - currentSample + 1)
{
samplesToRead = (int) (currentFrame.LastSampleNumber - currentSample + 1);
}
else
{
samplesToRead = samplesLeft;
}
MultiplexFrame(currentFrame,fr,samplesToRead,currentSample);
samplesLeft -= samplesToRead;
currentSample += (ulong)samplesToRead;
sampleCount += samplesToRead;
if (samplesLeft > 0)
{
currentFrame.Decode(physicalStream, flacStreamInfo);
frameDecoded = true;
}
if (sampleCount == count)
{
break;
}
}
}
catch (LostSynchronizationException)
{
if (AutoSyncronize)
{
SynchronizeRight();
}
}
catch (MalformedFileException)
{
if (AutoSyncronize)
{
SynchronizeRight();
}
}
catch (UnexpectedEndOfStreamException)
{
if (sampleCount == 0)
{
sampleCount = -1;
}
}
if (sampleCount != -1)
{
fr.ToByteArray(buffer, start);
}
return sampleCount;
}
private void MultiplexFrame(Frame fr, MultiplexedFrame mfr, int numSamples, ulong fromSample)
{
long startBuffer = mfr.BufferUsed;
for (int chan = 0; chan < mfr.NumChannels; chan++)
{
mfr.BufferUsed = startBuffer;
for (int sampleNum = 0; sampleNum < numSamples; sampleNum++)
{
int sampleToMultiplex = fr.output[chan, sampleNum+(int)(fromSample-fr.FirstSampleNumber)];
int bitsLeft = streamInfo.BitsPerSample;
int bitsRead = 0;
while (bitsLeft > 0)
{
int bitsToAdd = 0;
if (bitsLeft > 8 - mfr.BitOffset)
{
bitsToAdd = 8 - mfr.BitOffset;
}
else
{
bitsToAdd = bitsLeft;
}
mfr.Buffer[chan, mfr.BufferUsed] |= //(byte)(((byte)(sampleToMultiplex << bitsRead)) >> (8 - bitsToAdd));
(byte)(sampleToMultiplex >> streamInfo.BitsPerSample - bitsRead - bitsToAdd);
bitsRead += bitsToAdd;
mfr.BitOffset += bitsToAdd;
bitsLeft -= bitsToAdd;
if (mfr.BitOffset == 8)
{
mfr.BufferUsed++;
mfr.BitOffset = 0;
}
}
}
}
mfr.SampleCount += (ulong)numSamples;
}