static void WriteImpulsePCM(ISoundObj stereoImpulse, string fileNameL, string fileNameR)
{
ISoundObj sb;
WaveWriter writer;
ushort bits = 32;
int nTot = 196607;
int nBef = 98300;
// need padding before the sample.
// window the sample first, then pad it.
// Total length 65536, includes nPad and _peakPosL before impulse
int nPad = nBef - _peakPosL;
int usableLength = nTot - nPad;
int windowCenter = usableLength / 2;
int windowSide = _peakPosL * 2 / 3;
int windowFlat = windowCenter - windowSide;
ISoundObj ch = new SingleChannel(stereoImpulse, 0);
ISoundObj wn = new BlackmanHarris(windowCenter, windowSide, windowFlat);
wn.Input = ch;
sb = new SampleBuffer(wn).PaddedSubset(-nPad, nTot);
writer = new WaveWriter(fileNameL);
writer.Input = sb;
writer.Format = WaveFormat.IEEE_FLOAT;
writer.BitsPerSample = bits;
writer.SampleRate = _sampleRate;
writer.Raw = true;
writer.Normalization = -6.0;
writer.NormalizationType = NormalizationType.PEAK_DBFS;
writer.Run();
writer.Close();
double g = writer.Gain;
writer = null;
nPad = nBef - _peakPosR;
usableLength = nTot - nPad;
windowCenter = usableLength / 2;
windowSide = _peakPosR * 2 / 3;
windowFlat = windowCenter - windowSide;
ch = new SingleChannel(stereoImpulse, 1);
wn = new BlackmanHarris(windowCenter, windowSide, windowFlat);
wn.Input = ch;
sb = new SampleBuffer(wn).PaddedSubset(-nPad, nTot);
writer = new WaveWriter(fileNameR);
writer.Input = sb;
writer.Format = WaveFormat.IEEE_FLOAT;
writer.BitsPerSample = bits;
writer.SampleRate = _sampleRate;
writer.Raw = true;
writer.Gain = g;
writer.Run();
writer.Close();
writer = null;
}
static ISoundObj Splice(string infileL, int peakPosL, string infileR, int peakPosR, string outfile)
{
//int tmp1;
//bool tmp2;
WaveReader reader1 = new WaveReader(infileL, WaveFormat.IEEE_FLOAT, 32, 1);
// reader1.Skip(peakPosL, out tmp1, out tmp2);
SoundBuffer buff1 = new SoundBuffer(reader1);
buff1.ReadAll();
// Normalize loudness for each channel
double g = Loudness.WeightedVolume(buff1);
buff1.ApplyGain(1/g);
WaveReader reader2 = new WaveReader(infileR, WaveFormat.IEEE_FLOAT, 32, 1);
// reader2.Skip(peakPosR, out tmp1, out tmp2);
SoundBuffer buff2 = new SoundBuffer(reader2);
buff2.ReadAll();
g = Loudness.WeightedVolume(buff2);
buff2.ApplyGain(1/g);
ChannelSplicer splicer = new ChannelSplicer();
splicer.Add(buff1);
splicer.Add(buff2);
// General-purpose:
// Find the extremities of the DRC impulse,
// window asymmetrically.
//
// But, since we specifically used linear-phase filters on target and mic,
// we know that the impulse is centered.
// We want an impulse length (_filterLen)
// so window the 2048 samples at each end (which are pretty low to begin with - less than -100dB)
ISoundObj output;
int nCount = (int)(buff1.Count / 2);
if (nCount > _filterLen/2)
{
BlackmanHarris bhw = new BlackmanHarris(nCount, 2048, (nCount / 2) - 2048);
bhw.Input = splicer;
SampleBuffer sb = new SampleBuffer(bhw);
output = sb.Subset(_filterLen/2, _filterLen);
}
else
{
output = splicer;
}
ISoundObj result = output;
if (!_noSkew)
{
// Apply skew to compensate for time alignment in the impulse responses
Skewer skewer = new Skewer(true);
skewer.Input = output;
skewer.Skew = peakPosL - peakPosR;
result = skewer;
}
WaveWriter writer = new WaveWriter(outfile);
writer.Input = result;
writer.Dither = DitherType.NONE;
writer.Format = WaveFormat.IEEE_FLOAT;
writer.BitsPerSample = 32;
writer.SampleRate = _sampleRate;
writer.NumChannels = splicer.NumChannels;
if (Double.IsNaN(_gain))
{
writer.Normalization = 0;
}
else
{
writer.Gain = MathUtil.gain(_gain);
}
writer.Run();
writer.Close();
reader1.Close();
reader2.Close();
return result;
}
