/**
* Calculates MFCC features for each frame.
*
* @param wav recording object
* @param options transform options
*/
public override void Process(WaveFile wav, TransformOptions options)
{
wavFilename = wav.GetFilename();
int framesCount = wav.GetFramesCount();
Array.Resize(ref featureArray, framesCount);
if (m_indicator != null)
{
m_indicator.Start(0, framesCount - 1);
}
int N = wav.GetSamplesPerFrameZP();
UpdateFilters(wav.GetSampleFrequency(), N);
//filters.DrawMelFiltersBank("melfilters.png");
Complex[] frameSpectrum = new Complex[N];
double[] filtersOutput = new double[Dtw.MELFILTERS];
double[] frameMfcc = new double[m_paramsPerFrame];
Transform transform = new Transform(options);
// for each frame: FFT -> Mel filtration -> DCT
for (int i = 0; i < framesCount; ++i)
{
transform.Fft(wav.frames[i], ref frameSpectrum);
filters.ApplyAll(ref frameSpectrum, N, ref filtersOutput);
transform.Dct(filtersOutput, ref frameMfcc);
//featureArray[i] = frameMfcc;
featureArray[i] = new double[frameMfcc.Length];
frameMfcc.CopyTo(featureArray[i], 0);
if (m_indicator != null)
{
m_indicator.Progress(i);
}
}
if (m_indicator != null)
{
m_indicator.Stop();
}
}
