public EnvelopeLookup(PsyGlobal psyGlobal, VorbisInfo info)
{
_psyGlobal = psyGlobal;
var codecSetup = info.CodecSetup;
_minEnergy = codecSetup.PsyGlobalParam.PreEchoMinEnergy;
_cursor = codecSetup.BlockSizes[1] / 2;
_mdctWindow = new float[WindowLength];
_mdctLookup = new MdctLookup(WindowLength);
for (var i = 0; i < _mdctWindow.Length; i++)
{
_mdctWindow[i] = (float)Math.Sin(i / (WindowLength - 1.0) * Math.PI);
_mdctWindow[i] *= _mdctWindow[i];
}
_bands = new EnvelopeBand[PsyGlobal.EnvelopeBands];
// Magic follows
_bands[0] = new EnvelopeBand(2, 4);
_bands[1] = new EnvelopeBand(4, 5);
_bands[2] = new EnvelopeBand(6, 6);
_bands[3] = new EnvelopeBand(9, 8);
_bands[4] = new EnvelopeBand(13, 8);
_bands[5] = new EnvelopeBand(17, 8);
_bands[6] = new EnvelopeBand(22, 8);
_filters = Enumerable
.Range(0, PsyGlobal.EnvelopeBands * info.Channels)
.Select(s => new EnvelopeFilterState())
.ToArray();
_mark = new int[WindowLength];
}
public static LookupCollection Create(VorbisInfo info)
{
var codecSetup = info.CodecSetup;
var psyGlobal = new PsyGlobalLookup(codecSetup.PsyGlobalParam);
var envelope = new EnvelopeLookup(codecSetup.PsyGlobalParam, info);
// MDCT is tranform 0
var transform = new MdctLookup[2];
transform[0] = new MdctLookup(codecSetup.BlockSizes[0]);
transform[1] = new MdctLookup(codecSetup.BlockSizes[1]);
// analysis always needs an fft
var fftLookup = new DrftLookup[2];
fftLookup[0] = new DrftLookup(codecSetup.BlockSizes[0]);
fftLookup[1] = new DrftLookup(codecSetup.BlockSizes[1]);
// finish the codebooks
if (codecSetup.FullBooks == null)
{
codecSetup.FullBooks = new CodeBook[codecSetup.BookParams.Count];
for (var i = 0; i < codecSetup.BookParams.Count; i++)
{
codecSetup.FullBooks[i] = CodeBook.InitEncode(codecSetup.BookParams[i]);
}
}
var psyLookup = new PsyLookup[codecSetup.PsyParams.Count];
for (var i = 0; i < psyLookup.Length; i++)
{
psyLookup[i] = new PsyLookup(
codecSetup.PsyParams[i],
codecSetup.PsyGlobalParam,
codecSetup.BlockSizes[codecSetup.PsyParams[i].BlockFlag] / 2,
info.SampleRate);
}
// initialize all the backend lookups
var floor = new FloorLookup[codecSetup.FloorParams.Count];
for (var i = 0; i < floor.Length; i++)
{
floor[i] = new FloorLookup(codecSetup.FloorParams[i]);
}
var residue = new ResidueLookup[codecSetup.ResidueParams.Count];
for (var i = 0; i < residue.Length; i++)
{
residue[i] = new ResidueLookup(codecSetup.ResidueParams[i], new List <CodeBook>(codecSetup.FullBooks));
}
return(new LookupCollection(
envelope,
new List <MdctLookup>(transform),
psyGlobal,
new List <PsyLookup>(psyLookup),
new List <DrftLookup>(fftLookup),
new List <FloorLookup>(floor),
new List <ResidueLookup>(residue)));
}
