/// <summary>
/// Constructs an optimized convolution.
/// </summary>
public FastConvolver(float[] impulse, int delay = 0)
{
int fftSize = 2 << QMath.Log2Ceil(impulse.Length); // Zero padding for the falloff to have space
cache = new FFTCache(fftSize);
filter = new Complex[fftSize];
for (int sample = 0; sample < impulse.Length; ++sample)
{
filter[sample].Real = impulse[sample];
}
filter.InPlaceFFT(cache);
present = new Complex[fftSize];
future = new float[fftSize + delay];
this.delay = delay;
}
/// <summary>
/// Constructs an optimized convolution.
/// </summary>
public DualConvolver(float[] impulse1, float[] impulse2, int delay1 = 0, int delay2 = 0)
{
int impulseLength = Math.Max(impulse1.Length, impulse2.Length);
int fftSize = 2 << QMath.Log2Ceil(impulseLength); // Zero padding for the falloff to have space
cache = new FFTCache(fftSize);
filter = new Complex[fftSize];
for (int sample = 0; sample < impulse1.Length; ++sample)
{
filter[sample].Real = impulse1[sample];
}
for (int sample = 0; sample < impulse2.Length; ++sample)
{
filter[sample].Imaginary = impulse2[sample];
}
filter.InPlaceFFT(cache);
present = new Complex[fftSize];
future = new Complex[fftSize + Math.Max(delay1, delay2)];
this.delay1 = delay1;
this.delay2 = delay2;
}
/// <summary>
/// For E-AC-3, data for multiple blocks is included in an audio frame header.
/// </summary>
void AudioFrame()
{
expstre = header.Blocks != 6 || extractor.ReadBit();
ahte = header.Blocks == 6 && extractor.ReadBit();
snroffststr = extractor.Read(2);
transproce = extractor.ReadBit();
blkswe = extractor.ReadBit();
dithflage = extractor.ReadBit();
bamode = extractor.ReadBit();
frmfgaincode = extractor.ReadBit();
dbaflde = extractor.ReadBit();
skipflde = extractor.ReadBit();
spxattene = extractor.ReadBit();
if (header.ChannelMode > 1) // Not mono
{
cplstre[0] = true;
cplinu[0] = extractor.ReadBit();
for (int block = 1; block < cplstre.Length; ++block)
{
if (cplstre[block] = extractor.ReadBit())
{
cplinu[block] = extractor.ReadBit();
}
else
{
cplinu[block] = cplinu[block - 1];
}
}
}
else
{
for (int block = 1; block < cplstre.Length; ++block)
{
cplinu[block] = false;
}
}
// Exponent strategy data init
if (expstre)
{
for (int block = 0; block < cplexpstr.Length; ++block)
{
if (cplinu[block])
{
cplexpstr[block] = (ExpStrat)extractor.Read(2);
}
for (int channel = 0; channel < channels.Length; ++channel)
{
chexpstr[block][channel] = (ExpStrat)extractor.Read(2);
}
}
}
else
{
int ncplblks = 0;
for (int block = 0; block < cplinu.Length; ++block)
{
if (cplinu[block])
{
++ncplblks;
}
}
if (header.ChannelMode > 1 && ncplblks > 0)
{
frmcplexpstr = extractor.Read(5);
}
for (int channel = 0; channel < channels.Length; ++channel)
{
frmchexpstr[channel] = extractor.Read(5);
}
for (int block = 0; block < cplexpstr.Length; ++block)
{
cplexpstr[block] = frmcplexpstr_tbl[frmcplexpstr][block];
for (int channel = 0; channel < channels.Length; ++channel)
{
chexpstr[block][channel] = frmcplexpstr_tbl[frmchexpstr[channel]][block];
}
}
}
if (header.LFE)
{
for (int block = 0; block < lfeexpstr.Length; ++block)
{
lfeexpstr[block] = extractor.ReadBit();
}
}
// Converter exponent strategy data
if (header.StreamType == StreamTypes.Independent &&
(convexpstre = header.Blocks == 6 || extractor.ReadBit()))
{
for (int channel = 0; channel < channels.Length; ++channel)
{
convexpstr[channel] = extractor.Read(5);
}
}
// AHT data
if (ahte)
{
throw new UnsupportedFeatureException("AHT");
}
// Audio frame SNR offset data
if (snroffststr == 0)
{
frmcsnroffst = extractor.Read(6);
frmfsnroffst = extractor.Read(4);
}
// Transient pre-noise processing data
if (transproce)
{
for (int channel = 0; channel < channels.Length; ++channel)
{
if (chintransproc[channel] = extractor.ReadBit())
{
transprocloc[channel] = extractor.Read(10);
transproclen[channel] = extractor.Read(8);
}
}
}
// Spectral extension attenuation data
if (spxattene)
{
for (int ch = 0; ch < channels.Length; ++ch)
{
if (chinspxatten[ch] = extractor.ReadBit())
{
spxattencod[ch] = extractor.Read(5);
}
}
}
if (blkstrtinfoe = header.Blocks != 1 && extractor.ReadBit())
{
int nblkstrtbits = (header.Blocks - 1) * (4 + QMath.Log2Ceil(header.WordsPerSyncframe));
blkstrtinfo = extractor.Read(nblkstrtbits);
}
// Syntax state init
for (int channel = 0; channel < channels.Length; ++channel)
{
firstspxcos[channel] = true;
firstcplcos[channel] = true;
}
firstcplleak = true;
}
