public int processAudio(AudioBuffer ab) {
int dstBuffSize = ab.getSampleCount();
int NN;
FIRFilter ff;
// grab filter and NN
synchronized (lock) {
ff = filt;
NN = N;
}
if (chunk == null || overBuffSize != dstBuffSize * NN) {
overBuffSize = dstBuffSize * NN;
chunk = new AudioBuffer("oversampled", 1, overBuffSize, ab.getSampleRate() * NN);
}
chunk.makeSilence();
src.processAudio(chunk);
ff.processAudio(chunk);
float upa[] = chunk.getChannel(0);
for (int chn = 0; chn < ab.getChannelCount(); chn++) {
float a[] = ab.getChannel(chn);
for (int i = 0; i < dstBuffSize; i++) {
a[i] = upa[NN * i];
}
}
return AUDIO_OK;
}
void createFilter(int n, float coeffs[]) {
// float alpha = 5;
// int order = 50;
// float bandwidth = 00;
// FIRFilterDesign d = new FIRFilterDesign(alpha, sampRate * n, sampRate / 2.4f,
// FIRFilterDesign.LPF, order,
// FIRFilterDesign.KAISER, bandwidth);
// float coeffs[] = d.getCoefficients();
FIRFilter filt1 = new FIRFilter();
filt1.setCoeffs(coeffs);
// there is a miniscule chance that concurrency problems might happen here.
synchronized (lock) {
filt = filt1;
N = n;
}
}
