public void PacketIn(OggPacket packet)
{
if (packet == null)
{
return;
}
ClearReturnedBody();
var bytes = packet.PacketData.Length;
var lacingValueCount = (int)(bytes / 255f + 1);
// make sure we have the buffer storage
ExpandBody(bytes);
ExpandLacing(lacingValueCount);
// Copy in the submitted packet.
Array.Copy(packet.PacketData, 0, _bodyData, _bodyFill, bytes);
_bodyFill += bytes;
// Store lacing vals for this packet
int i;
for (i = 0; i < lacingValueCount - 1; i++)
{
_lacingValues[_lacingFill + i] = 255;
_granuleValues[_lacingFill + i] = _granulePosition;
}
_lacingValues[_lacingFill + i] = (int)(bytes % 255f);
_granulePosition = _granuleValues[_lacingFill + i] = packet.GranulePosition;
// flag the first segment as the beginning of the packet
_lacingValues[_lacingFill] |= 0x100;
_lacingFill += lacingValueCount;
if (packet.EndOfStream)
{
Finished = true;
}
}
public bool PacketOut(out OggPacket packet)
{
packet = null;
// Have we started?
if (!_preExtrapolated)
{
return(false);
}
// Are we done?
if (_eofFlag == -1)
{
return(false);
}
var codecSetup = _vorbisInfo.CodecSetup;
// By our invariant, we have lW, W and centerW set. Search for
// the next boundary so we can determine nW (the next window size)
// which lets us compute the shape of the current block's window
// we do an envelope search even on a single blocksize; we may still
// be throwing more bits at impulses, and envelope search handles
// marking impulses too.
var testWindow =
_centerWindow +
codecSetup.BlockSizes[_currentWindow] / 4 +
codecSetup.BlockSizes[1] / 2 +
codecSetup.BlockSizes[0] / 4;
var bp = _lookups.EnvelopeLookup.Search(_pcm, _pcmCurrent, _centerWindow, testWindow);
if (bp == -1)
{
if (_eofFlag == 0)
{
return(false); // not enough data currently to search for a full int block
}
_nextWindow = 0;
}
else
{
_nextWindow = codecSetup.BlockSizes[0] == codecSetup.BlockSizes[1] ? 0 : bp;
}
var centerNext = _centerWindow
+ codecSetup.BlockSizes[_currentWindow] / 4
+ codecSetup.BlockSizes[_nextWindow] / 4;
// center of next block + next block maximum right side.
var blockbound = centerNext + codecSetup.BlockSizes[_nextWindow] / 2;
// Not enough data yet
if (_pcmCurrent < blockbound)
{
return(false);
}
// copy the vectors; ampPtr uses the local storage in vb
// ampPtr tracks 'strongest peak' for later psychoacoustics
var n = codecSetup.BlockSizes[_currentWindow] / 2;
_lookups.PsyGlobalLookup.DecayAmpMax(n, _vorbisInfo.SampleRate);
var pcmEnd = codecSetup.BlockSizes[_currentWindow];
var pcm = new float[_pcm.Length][];
var beginWindow = _centerWindow - codecSetup.BlockSizes[_currentWindow] / 2;
for (var channel = 0; channel < _pcm.Length; channel++)
{
pcm[channel] = new float[pcmEnd];
Array.Copy(_pcm[channel], beginWindow, pcm[channel], 0, pcm[channel].Length);
}
// handle eof detection: eof==0 means that we've not yet received EOF eof>0
// marks the last 'real' sample in pcm[] eof<0 'no more to do'; doesn't get here
var eofFlag = false;
if (_eofFlag != 0)
{
if (_centerWindow >= _eofFlag)
{
_eofFlag = -1;
eofFlag = true;
}
}
var data = PerformAnalysis(pcm, pcmEnd);
packet = new OggPacket(data, eofFlag, _granulePosition, _sequence++);
if (!eofFlag)
{
AdvanceStorageVectors(centerNext);
}
return(true);
}
