internal static VorbisMode Init(VorbisStreamDecoder vorbis, DataPacket packet)
{
var mode = new VorbisMode(vorbis);
mode.BlockFlag = packet.ReadBit();
mode.WindowType = (int)packet.ReadBits(16);
mode.TransformType = (int)packet.ReadBits(16);
var mapping = (int)packet.ReadBits(8);
if (mode.WindowType != 0 || mode.TransformType != 0 || mapping >= vorbis.Maps.Length)
{
throw new InvalidDataException();
}
mode.Mapping = vorbis.Maps[mapping];
mode.BlockSize = mode.BlockFlag ? vorbis.Block1Size : vorbis.Block0Size;
// now pre-calc the window(s)...
if (mode.BlockFlag)
{
// long block
mode._windows = new float[4][];
mode._windows[0] = new float[vorbis.Block1Size];
mode._windows[1] = new float[vorbis.Block1Size];
mode._windows[2] = new float[vorbis.Block1Size];
mode._windows[3] = new float[vorbis.Block1Size];
}
else
{
// short block
mode._windows = new float[1][];
mode._windows[0] = new float[vorbis.Block0Size];
}
mode.CalcWindows();
return(mode);
}
