void Loop()
{
float phase = GetLocalTime();
int samples = 2048;
int hz = 44100;
var duration =
Math.Round((double)samples / hz, 4);
float[] X = new float[samples];
step++;
for (int s = 0; s < samples; s++)
{
var f = Random.Next() % hz;
var ampl =
Math.Sin(f * 2d * Math.PI * s * (1d / hz) + phase);
// ampl +=
// Math.Sin(120 * 43.06640625 * 2d * Math.PI * s * (1d / hz) + phase);
// ampl +=
// Math.Sin(240 * Math.PI * s * (1d / hz) + phase);
// ampl +=
// Math.Sin(880 * Math.PI * s * (1d / hz) + phase);
// ampl +=
// Math.Sin(1350 * Math.PI * s * (1d / hz) + phase);
// ampl +=
// Math.Sin(7252 * Math.PI * s * (1d / hz) + phase);
// ampl /= 7;
X[s] = (float)ampl;
}
var fft = Complex.FFT(X);
// Print.Dump(fft, Stream.Hz);
if (step >= 450)
{
for (int s = 0; s < samples; s++)
{
fft[s].Scale(1f);
}
double h = hz
/ (double)samples;
for (int s = 0; s < samples / 2; s++)
{
var f =
h * 0.5 + (s * h);
var dB = System.Audio.dB.FromAmplitude(2 * fft[s].Magnitude);
bool filterOut =
!Ranges.IsInRange(f, dB);
if (filterOut)
{
var n = samples - s;
fft[s].Scale(0f);
if (s > 0 && n > s && n >= 0 &&
n < samples)
{
fft[n].Scale(0f);
}
}
}
}
Stream.Push(fft);
}