Spectrogram LPC_to_Spectrogram (LPC me, double dfMin, double bandwidthReduction, double deEmphasisFrequency) {
try {
double samplingFrequency = 1.0 / my samplingPeriod;
long nfft = 2;
if (dfMin <= 0) {
nfft = 512; dfMin = samplingFrequency / nfft;
}
while (samplingFrequency / nfft > dfMin || nfft <= my maxnCoefficients) {
nfft *= 2;
}
double freqStep = samplingFrequency / nfft;
autoSpectrogram thee = (Spectrogram) Spectrogram_create (my xmin, my xmax, my nx, my dx, my x1,
0, samplingFrequency / 2, nfft / 2 + 1, freqStep, 0);
for (long i = 1; i <= my nx; i++) {
double t = Sampled_indexToX (me, i);
autoSpectrum spec = LPC_to_Spectrum (me, t, dfMin, bandwidthReduction, deEmphasisFrequency);
for (long j = 1; j <= spec -> nx; j++) {
double re = spec -> z[1][j], im = spec -> z[2][j];
thy z[j][i] = re * re + im * im;
}
}
return thee.transfer();
} catch (MelderError) {
Melder_throw (me, ": no Spectrogram created.");
}
}
Spectrogram Matrix_to_Spectrogram (Matrix me) {
try {
autoSpectrogram thee = Spectrogram_create (my xmin, my xmax, my nx, my dx, my x1, my ymin, my ymax, my ny, my dy, my y1);
NUMmatrix_copyElements (my z, thy z, 1, my ny, 1, my nx);
return thee.transfer();
} catch (MelderError) {
Melder_throw (me, U": not converted to Spectrogram.");
}
}
autoSpectrogram ComplexSpectrogram_to_Spectrogram (ComplexSpectrogram me) {
try {
autoSpectrogram thee = Spectrogram_create (my xmin, my xmax, my nx, my dx, my x1, my ymin, my ymax, my ny, my dy, my y1);
NUMmatrix_copyElements<double> (my z, thy z, 1, my ny, 1, my nx);
return thee;
} catch (MelderError) {
Melder_throw (me, U": not converted to Spectrogram.");
}
}
Spectrogram Spectrum_to_Spectrogram (I) {
iam (Spectrum);
try {
autoSpectrogram thee = Spectrogram_create (0, 1, 1, 1, 0.5, my xmin, my xmax, my nx, my dx, my x1);
for (long i = 1; i <= my nx; i ++)
thy z [i] [1] = my z [1] [i] * my z [1] [i] + my z [2] [i] * my z [2] [i];
return thee.transfer();
} catch (MelderError) {
Melder_throw (me, U": not converted to Spectrogram.");
}
}
Spectrogram FormantFilter_to_Spectrogram (FormantFilter me) {
try {
autoSpectrogram thee = Spectrogram_create (my xmin, my xmax, my nx, my dx, my x1, my ymin, my ymax, my ny, my dy, my y1);
for (long i = 1; i <= my ny; i++) {
for (long j = 1; j <= my nx; j++) {
thy z[i][j] = 4e-10 * pow (10, my z[i][j] / 10);
}
}
return thee.transfer ();
} catch (MelderError) {
Melder_throw (U"Spectrogram not created.");
}
}
autoSpectrogram Sound_to_Spectrogram (Sound me, double effectiveAnalysisWidth, double fmax,
double minimumTimeStep1, double minimumFreqStep1, enum kSound_to_Spectrogram_windowShape windowType,
double maximumTimeOversampling, double maximumFreqOversampling)
{
try {
double nyquist = 0.5 / my dx;
double physicalAnalysisWidth =
windowType == kSound_to_Spectrogram_windowShape_GAUSSIAN ? 2 * effectiveAnalysisWidth : effectiveAnalysisWidth;
double effectiveTimeWidth = effectiveAnalysisWidth / sqrt (NUMpi);
double effectiveFreqWidth = 1 / effectiveTimeWidth;
double minimumTimeStep2 = effectiveTimeWidth / maximumTimeOversampling;
double minimumFreqStep2 = effectiveFreqWidth / maximumFreqOversampling;
double timeStep = minimumTimeStep1 > minimumTimeStep2 ? minimumTimeStep1 : minimumTimeStep2;
double freqStep = minimumFreqStep1 > minimumFreqStep2 ? minimumFreqStep1 : minimumFreqStep2;
double duration = my dx * (double) my nx, windowssq = 0.0;
/*
* Compute the time sampling.
*/
long nsamp_window = (long) floor (physicalAnalysisWidth / my dx);
long halfnsamp_window = nsamp_window / 2 - 1;
nsamp_window = halfnsamp_window * 2;
if (nsamp_window < 1)
Melder_throw (U"Your analysis window is too short: less than two samples.");
if (physicalAnalysisWidth > duration)
Melder_throw (U"Your sound is too short:\n"
U"it should be at least as long as ",
windowType == kSound_to_Spectrogram_windowShape_GAUSSIAN ? U"two window lengths." : U"one window length.");
long numberOfTimes = 1 + (long) floor ((duration - physicalAnalysisWidth) / timeStep); // >= 1
double t1 = my x1 + 0.5 * ((double) (my nx - 1) * my dx - (double) (numberOfTimes - 1) * timeStep);
/* Centre of first frame. */
/*
* Compute the frequency sampling of the FFT spectrum.
*/
if (fmax <= 0.0 || fmax > nyquist) fmax = nyquist;
long numberOfFreqs = (long) floor (fmax / freqStep);
if (numberOfFreqs < 1) return autoSpectrogram ();
long nsampFFT = 1;
while (nsampFFT < nsamp_window || nsampFFT < 2 * numberOfFreqs * (nyquist / fmax))
nsampFFT *= 2;
long half_nsampFFT = nsampFFT / 2;
/*
* Compute the frequency sampling of the spectrogram.
*/
long binWidth_samples = (long) floor (freqStep * my dx * nsampFFT);
if (binWidth_samples < 1) binWidth_samples = 1;
double binWidth_hertz = 1.0 / (my dx * nsampFFT);
freqStep = binWidth_samples * binWidth_hertz;
numberOfFreqs = (long) floor (fmax / freqStep);
if (numberOfFreqs < 1) return autoSpectrogram ();
autoSpectrogram thee = Spectrogram_create (my xmin, my xmax, numberOfTimes, timeStep, t1,
0.0, fmax, numberOfFreqs, freqStep, 0.5 * (freqStep - binWidth_hertz));
autoNUMvector <double> frame (1, nsampFFT);
autoNUMvector <double> spec (1, nsampFFT);
autoNUMvector <double> window (1, nsamp_window);
autoNUMfft_Table fftTable;
NUMfft_Table_init (& fftTable, nsampFFT);
autoMelderProgress progress (U"Sound to Spectrogram...");
for (long i = 1; i <= nsamp_window; i ++) {
double nSamplesPerWindow_f = physicalAnalysisWidth / my dx;
double phase = (double) i / nSamplesPerWindow_f; // 0 .. 1
double value;
switch (windowType) {
case kSound_to_Spectrogram_windowShape_SQUARE:
value = 1.0;
break; case kSound_to_Spectrogram_windowShape_HAMMING:
value = 0.54 - 0.46 * cos (2.0 * NUMpi * phase);
break; case kSound_to_Spectrogram_windowShape_BARTLETT:
value = 1.0 - fabs ((2.0 * phase - 1.0));
break; case kSound_to_Spectrogram_windowShape_WELCH:
value = 1.0 - (2.0 * phase - 1.0) * (2.0 * phase - 1.0);
break; case kSound_to_Spectrogram_windowShape_HANNING:
value = 0.5 * (1.0 - cos (2.0 * NUMpi * phase));
break; case kSound_to_Spectrogram_windowShape_GAUSSIAN:
{
double imid = 0.5 * (double) (nsamp_window + 1), edge = exp (-12.0);
phase = ((double) i - imid) / nSamplesPerWindow_f; /* -0.5 .. +0.5 */
value = (exp (-48.0 * phase * phase) - edge) / (1.0 - edge);
break;
}
break; default:
value = 1.0;
}
window [i] = (float) value;
windowssq += value * value;
}
double oneByBinWidth = 1.0 / windowssq / binWidth_samples;
for (long iframe = 1; iframe <= numberOfTimes; iframe ++) {
double t = Sampled_indexToX (thee.peek(), iframe);
long leftSample = Sampled_xToLowIndex (me, t), rightSample = leftSample + 1;
long startSample = rightSample - halfnsamp_window;
long endSample = leftSample + halfnsamp_window;
Melder_assert (startSample >= 1);
Melder_assert (endSample <= my nx);
for (long i = 1; i <= half_nsampFFT; i ++) {
spec [i] = 0.0;
}
for (long channel = 1; channel <= my ny; channel ++) {
for (long j = 1, i = startSample; j <= nsamp_window; j ++) {
frame [j] = my z [channel] [i ++] * window [j];
}
for (long j = nsamp_window + 1; j <= nsampFFT; j ++) frame [j] = 0.0f;
Melder_progress (iframe / (numberOfTimes + 1.0),
U"Sound to Spectrogram: analysis of frame ", iframe, U" out of ", numberOfTimes);
/* Compute Fast Fourier Transform of the frame. */
NUMfft_forward (& fftTable, frame.peek()); // complex spectrum
/* Put power spectrum in frame [1..half_nsampFFT + 1]. */
spec [1] += frame [1] * frame [1]; // DC component
for (long i = 2; i <= half_nsampFFT; i ++)
spec [i] += frame [i + i - 2] * frame [i + i - 2] + frame [i + i - 1] * frame [i + i - 1];
spec [half_nsampFFT + 1] += frame [nsampFFT] * frame [nsampFFT]; // Nyquist frequency. Correct??
}
if (my ny > 1 ) for (long i = 1; i <= half_nsampFFT; i ++) {
spec [i] /= my ny;
}
/* Bin into frame [1..nBands]. */
for (long iband = 1; iband <= numberOfFreqs; iband ++) {
long leftsample = (iband - 1) * binWidth_samples + 1, rightsample = leftsample + binWidth_samples;
float power = 0.0f;
for (long i = leftsample; i < rightsample; i ++) power += spec [i];
thy z [iband] [iframe] = power * oneByBinWidth;
}
}
return thee;
} catch (MelderError) {
Melder_throw (me, U": spectrogram analysis not performed.");
}
}
autoSpectrogram Sound_and_Pitch_to_Spectrogram (Sound me, Pitch thee, double analysisWidth, double dt, double f1_hz, double fmax_hz, double df_hz, double relative_bw) {
try {
double t1, windowDuration = 2.0 * analysisWidth; /* gaussian window */
double nyquist = 0.5 / my dx, samplingFrequency = 2.0 * nyquist, fmin_hz = 0.0;
long numberOfFrames, f0_undefined = 0.0;
if (my xmin > thy xmin || my xmax > thy xmax) Melder_throw
(U"The domain of the Sound is not included in the domain of the Pitch.");
double f0_median = Pitch_getQuantile (thee, thy xmin, thy xmax, 0.5, kPitch_unit_HERTZ);
if (f0_median == NUMundefined || f0_median == 0.0) {
f0_median = 100.0;
Melder_warning (U"Pitch values undefined. Bandwith fixed to 100 Hz. ");
}
if (f1_hz <= 0.0) {
f1_hz = 100.0;
}
if (fmax_hz <= 0.0) {
fmax_hz = nyquist;
}
if (df_hz <= 0.0) {
df_hz = f0_median / 2.0;
}
if (relative_bw <= 0.0) {
relative_bw = 1.1;
}
fmax_hz = MIN (fmax_hz, nyquist);
long numberOfFilters = lround ( (fmax_hz - f1_hz) / df_hz);
Sampled_shortTermAnalysis (me, windowDuration, dt, &numberOfFrames, &t1);
autoSpectrogram him = Spectrogram_create (my xmin, my xmax, numberOfFrames, dt, t1, fmin_hz, fmax_hz, numberOfFilters, df_hz, f1_hz);
// Temporary objects
autoSound sframe = Sound_createSimple (1, windowDuration, samplingFrequency);
autoSound window = Sound_createGaussian (windowDuration, samplingFrequency);
autoMelderProgress progress (U"Sound & Pitch: To FormantFilter");
for (long iframe = 1; iframe <= numberOfFrames; iframe++) {
double t = Sampled_indexToX (him.get(), iframe);
double b, f0 = Pitch_getValueAtTime (thee, t, kPitch_unit_HERTZ, 0);
if (f0 == NUMundefined || f0 == 0.0) {
f0_undefined ++;
f0 = f0_median;
}
b = relative_bw * f0;
Sound_into_Sound (me, sframe.get(), t - windowDuration / 2.0);
Sounds_multiply (sframe.get(), window.get());
Sound_into_Spectrogram_frame (sframe.get(), him.get(), iframe, b);
if (iframe % 10 == 1) {
Melder_progress ( (double) iframe / numberOfFrames, U"Frame ", iframe, U" out of ",
numberOfFrames, U".");
}
}
_Spectrogram_windowCorrection (him.get(), window -> nx);
return him;
} catch (MelderError) {
Melder_throw (U"FormantFilter not created from Pitch & FormantFilter.");
}
}
