private void ProcessParameterChange(DataPacket packet)
{
_parameterChangePacket = null;
// try to do a stream header...
var wasPeek = false;
var doFullReset = false;
if (ProcessStreamHeader(packet))
{
packet.Done();
wasPeek = true;
doFullReset = true;
packet = _packetProvider.PeekNextPacket();
if (packet == null)
{
throw new InvalidDataException("Couldn't get next packet!");
}
}
// try to do a comment header...
if (LoadComments(packet))
{
if (wasPeek)
{
_packetProvider.GetNextPacket().Done();
}
else
{
packet.Done();
}
wasPeek = true;
packet = _packetProvider.PeekNextPacket();
if (packet == null)
{
throw new InvalidDataException("Couldn't get next packet!");
}
}
// try to do a book header...
if (LoadBooks(packet))
{
if (wasPeek)
{
_packetProvider.GetNextPacket().Done();
}
else
{
packet.Done();
}
}
ResetDecoder(doFullReset);
}
private void DecodeNextPacket()
{
_sw.Start();
DataPacket packet = null;
try
{
// get the next packet
var packetProvider = _packetProvider;
if (packetProvider != null)
{
packet = packetProvider.GetNextPacket();
}
// if the packet is null, we've hit the end or the packet reader has been disposed...
if (packet == null)
{
_eosFound = true;
return;
}
// keep our page count in sync
if (!_pagesSeen.Contains((_lastPageSeen = packet.PageSequenceNumber)))
{
_pagesSeen.Add(_lastPageSeen);
}
// check for resync
if (packet.IsResync)
{
ResetDecoder(false); // if we're a resync, our current decoder state is invalid...
}
// check for parameter change
if (packet == _parameterChangePacket)
{
_isParameterChange = true;
ProcessParameterChange(packet);
return;
}
if (!UnpackPacket(packet))
{
packet.Done();
_wasteBits += 8 * packet.Length;
return;
}
packet.Done();
// we can now safely decode all the data without having to worry about a corrupt or partial packet
DecodePacket();
var samplesDecoded = OverlapSamples();
// we can do something cool here... mark down how many samples were decoded in this packet
if (packet.GranuleCount.HasValue == false)
{
packet.GranuleCount = samplesDecoded;
}
// update our position
UpdatePosition(samplesDecoded, packet);
// a little statistical housekeeping...
var sc = Utils.Sum(_sampleCountHistory) + samplesDecoded;
_bitsPerPacketHistory.Enqueue((int)packet.BitsRead);
_sampleCountHistory.Enqueue(samplesDecoded);
while (sc > _sampleRate)
{
_bitsPerPacketHistory.Dequeue();
sc -= _sampleCountHistory.Dequeue();
}
}
catch
{
if (packet != null)
{
packet.Done();
}
throw;
}
finally
{
_sw.Stop();
}
}