/**
* Keep
*
* @param input
* @return
*/
public static AudioSignal truncate(AudioSignal input) {
int duration = 100;
if (input.getLength() * 1000 / input.samplingRate < duration) {
throw new IllegalStateException("Input should be at last " + duration + " ms");
}
int keep = (duration * input.samplingRate / 1000) & 0xFFFFFFFE;
float[] result = new float[keep];
int middle = input.getLength() / 2;
System.arraycopy(input.data, middle - (keep / 2), result, 0, keep);
return new AudioSignal(result, input.samplingRate);
}
public static void fadeInOut(AudioSignal input) {
int size = input.getLength();
int fadeSize = size * 5 / 100;
for (int i = 0; i < fadeSize; i++) {
input.data[i] = input.data[i] * (((float) i + 1) / fadeSize);
input.data[size - i - 1] = input.data[size - i - 1] * (((float) i + 1) / fadeSize);
}
}
public static void coupe100(AudioSignal input) {
int fs = input.samplingRate;
int N = input.getLength();
float[] Y = Arrays.copyOf(input.data, 2 * N);
FloatFFT_1D fft = new FloatFFT_1D(N);
fft.realForwardFull(Y);
int threshold = 100 * 2;
Arrays.fill(Y, 0, Math.round(threshold * (float) N / fs), 0);
Arrays.fill(Y, Math.round(2 * N - threshold * (float) N / fs), 2 * N - 1, 0);
fft.complexInverse(Y, true);
for (int i = 0; i < N; i++) {
input.data[i] = Y[2 * i];
}
}
public static int[] formants(AudioSignal input) {
int[] formants = new int[4];
float[] phon = new float[input.getLength() / 3];
int fs = input.samplingRate / 3;
for (int i = 0; i < phon.length; i++) {
phon[i] = input.data[i * 3];
}
int fmax = fs / 2;
int TFenetre = 23;
int quefrence = (int) Math.floor(1000 * ((float) phon.length) / fs);
List<float[]> deconvols = deconvol(phon, fs, TFenetre, quefrence);
int Nf = deconvols.get(0).length;
float[] magnitude = new float[Nf];
for (int i = 0; i < magnitude.length; i++) {
double sum = 0;
for (float[] deconvol : deconvols) {
sum += Math.abs(deconvol[i]);
}
magnitude[i] = (float) (sum / deconvols.size());
}
int[][] B =
new int[][] {
new int[] {235, 775},
new int[] {675, 2265},
new int[] {2145, 2995},
new int[] {3045, 3495}
};
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 2; j++) {
B[i][j] = Math.min(Math.round(B[i][j] * Nf / fmax), Nf);
}
}
int i = 0;
while (i < 4) {
int b1 = B[i][0];
int b2 = B[i][1];
float max = 0;
int maxIdx = 0;
for (int idx = b1; idx <= b2; idx++) {
if (magnitude[idx] > max) {
max = magnitude[idx];
maxIdx = idx;
}
}
formants[i] = Math.round(maxIdx * fmax / Nf);
if (i == 1 && (formants[1] - formants[0]) <= 410) { // distance minimale entre F1 et F2
if (formants[1] <= 763) {
// ce sont ceux qui posent le plus problème
formants[0] = formants[1];
}
B[1][0] = b1 + 1;
i = 0;
}
i++;
}
return formants;
}