static int Sound_into_MelFilter_frame (Sound me, MelFilter thee, long frame) {
autoMatrix pv = Sound_to_spectralpower (me);
double z1 = pv -> x1;
double dz = pv -> dx;
long nf = pv -> nx;
double df = thy dy;
for (long i = 1; i <= thy ny; i++) {
double p = 0;
double fc_mel = thy y1 + (i - 1) * df;
double fc_hz = MELTOHZ (fc_mel);
double fl_hz = MELTOHZ (fc_mel - df);
double fh_hz = MELTOHZ (fc_mel + df);
double *pow = pv -> z[1];
for (long j = 1; j <= nf; j++) {
// Filter with a triangular filter the power (=amplitude-squared)
double f = z1 + (j - 1) * dz;
double a = NUMtriangularfilter_amplitude (fl_hz, fc_hz, fh_hz, f);
p += a * pow[j] ;
}
thy z[i][frame] = p;
}
return 1;
}
void MelFilter_drawFilterFunctions (MelFilter me, Graphics g,
int toFreqScale, int fromFilter, int toFilter, double zmin, double zmax,
int dbScale, double ymin, double ymax, int garnish) {
if (! checkLimits (me, FilterBank_MEL, toFreqScale, & fromFilter, & toFilter,
& zmin, & zmax, dbScale, & ymin, & ymax)) {
return;
}
long n = 1000;
autoNUMvector<double> a (1, n);
Graphics_setInner (g);
Graphics_setWindow (g, zmin, zmax, ymin, ymax);
for (long j = fromFilter; j <= toFilter; j++) {
double df = (zmax - zmin) / (n - 1);
double fc_mel = my y1 + (j - 1) * my dy;
double fc_hz = MELTOHZ (fc_mel);
double fl_hz = MELTOHZ (fc_mel - my dy);
double fh_hz = MELTOHZ (fc_mel + my dy);
long ibegin, iend;
for (long i = 1; i <= n; i++) {
// Filterfunction: triangular on a linear frequency scale AND a linear amplitude scale.
double f = zmin + (i - 1) * df;
double z = scaleFrequency (f, toFreqScale, FilterBank_HERTZ);
if (z == NUMundefined) {
a[i] = NUMundefined;
} else {
a[i] = NUMtriangularfilter_amplitude (fl_hz, fc_hz, fh_hz, z);
if (dbScale) {
a[i] = to_dB (a[i], 10, ymin);
}
}
}
setDrawingLimits (a.peek(), n, ymin, ymax, &ibegin, &iend);
if (ibegin <= iend) {
double fmin = zmin + (ibegin - 1) * df;
double fmax = zmax - (n - iend) * df;
Graphics_function (g, a.peek(), ibegin, iend, fmin, fmax);
}
}
Graphics_unsetInner (g);
if (garnish) {
double distance = dbScale ? 10 : 1;
char32 const *ytext = dbScale ? U"Amplitude (dB)" : U"Amplitude";
Graphics_drawInnerBox (g);
Graphics_marksBottom (g, 2, 1, 1, 0);
Graphics_marksLeftEvery (g, 1, distance, 1, 1, 0);
Graphics_textLeft (g, 1, ytext);
Graphics_textBottom (g, 1, GetFreqScaleText (toFreqScale));
}
}
static void Sound_into_MelSpectrogram_frame (Sound me, MelSpectrogram thee, long frame) {
autoSpectrum him = Sound_to_Spectrum_power (me);
for (long ifilter = 1; ifilter <= thy ny; ifilter ++) {
double power = 0;
double fc_mel = thy y1 + (ifilter - 1) * thy dy;
double fc_hz = thy v_frequencyToHertz (fc_mel);
double fl_hz = thy v_frequencyToHertz (fc_mel - thy dy);
double fh_hz = thy v_frequencyToHertz (fc_mel + thy dy);
long ifrom, ito;
Sampled_getWindowSamples (him.get(), fl_hz, fh_hz, &ifrom, &ito);
for (long i = ifrom; i <= ito; i++) {
// Bin with a triangular filter the power (=amplitude-squared)
double f = his x1 + (i - 1) * his dx;
double a = NUMtriangularfilter_amplitude (fl_hz, fc_hz, fh_hz, f);
power += a * his z[1][i];
}
thy z[ifilter][frame] = power;
}
}
void MelSpectrogram_drawTriangularFilterFunctions (MelSpectrogram me, Graphics g, bool xIsHertz, int fromFilter, int toFilter, double zmin, double zmax, bool yscale_dB, double ymin, double ymax, int garnish) {
double xmin = zmin, xmax = zmax;
if (zmin >= zmax) {
zmin = my ymin; zmax = my ymax; // mel
xmin = xIsHertz ? my v_frequencyToHertz (zmin) : zmin;
xmax = xIsHertz ? my v_frequencyToHertz (zmax) : zmax;
}
if (xIsHertz) {
zmin = my v_hertzToFrequency (xmin); zmax = my v_hertzToFrequency (xmax);
}
if (ymin >= ymax) {
ymin = yscale_dB ? -60 : 0;
ymax = yscale_dB ? 0 : 1;
}
fromFilter = fromFilter <= 0 ? 1 : fromFilter;
toFilter = toFilter <= 0 || toFilter > my ny ? my ny : toFilter;
if (fromFilter > toFilter) {
fromFilter = 1; toFilter = my ny;
}
long n = xIsHertz ? 1000 : 500;
autoNUMvector<double> xz (1, n), xhz (1,n), y (1, n);
Graphics_setInner (g);
Graphics_setWindow (g, xmin, xmax, ymin, ymax);
double dz = (zmax - zmin) / (n - 1);
for (long iz = 1; iz <= n; iz++) {
double f = zmin + (iz - 1) * dz;
xz[iz] = f;
xhz[iz] = my v_frequencyToHertz (f); // just in case we need the linear scale
}
for (long ifilter = fromFilter; ifilter <= toFilter; ifilter++) {
double zc = Matrix_rowToY (me, ifilter), zl = zc - my dy, zh = zc + my dy;
double xo1, yo1, xo2, yo2;
if (yscale_dB) {
for (long iz = 1; iz <= n; iz++) {
double z = xz[iz];
double amp = NUMtriangularfilter_amplitude (zl, zc, zh, z);
y[iz] = yscale_dB ? (amp > 0 ? 20 * log10 (amp) : ymin - 10) : amp;
}
double x1 = xIsHertz ? xhz[1] : xz[1], y1 = y[1];
if (NUMdefined (y1)) {
for (long iz = 1; iz <= n; iz++) {
double x2 = xIsHertz ? xhz[iz] : xz[iz], y2 = y[iz];
if (NUMdefined (y2)) {
if (NUMclipLineWithinRectangle (x1, y1, x2, y2, xmin, ymin, xmax, ymax, &xo1, &yo1, &xo2, &yo2)) {
Graphics_line (g, xo1, yo1, xo2, yo2);
}
}
x1 = x2; y1 = y2;
}
}
} else {
double x1 = xIsHertz ? my v_frequencyToHertz (zl) : zl;
double x2 = xIsHertz ? my v_frequencyToHertz (zc) : zc;
if (NUMclipLineWithinRectangle (x1, 0, x2, 1, xmin, ymin, xmax, ymax, &xo1, &yo1, &xo2, &yo2)) {
Graphics_line (g, xo1, yo1, xo2, yo2);
}
double x3 = xIsHertz ? my v_frequencyToHertz (zh) : zh;
if (NUMclipLineWithinRectangle (x2, 1, x3, 0, xmin, ymin, xmax, ymax, &xo1, &yo1, &xo2, &yo2)) {
Graphics_line (g, xo1, yo1, xo2, yo2);
}
}
}
Graphics_unsetInner (g);
if (garnish) {
Graphics_drawInnerBox (g);
Graphics_marksBottom (g, 2, 1, 1, 0);
Graphics_marksLeftEvery (g, 1, yscale_dB ? 10 : 0.5, 1, 1, 0);
Graphics_textLeft (g, 1, yscale_dB ? U"Amplitude (dB)" : U"Amplitude");
Graphics_textBottom (g, 1, Melder_cat (U"Frequency (", ( xIsHertz ? U"Hz" : my v_getFrequencyUnit () ), U")"));
}
}