public static Matrix Noise()
{
int Fs = 1024 * 2;
Debug.Assert(Fs == 1024 * 2);
var Model = new Matrix(113);
for (int i = 0; i < Model.Capacity; i++)
{
double[] re = new double[CBOW.DIMS],
im = new double[CBOW.DIMS];
for (int j = 0; j < CBOW.DIMS; j++)
{
re[j] = ((global::Random.Next() & 0xFFFF) / (65536f))
* ((global::Random.Next() & 0xFFFF) / (65536f));
im[j] = Envelopes.MIDI2FREQ(j);
if (((global::Random.Next() & 0xFFFF) / (65536f)) > 0.3)
{
re[j] = 0;
}
}
Vector it = new Vector("𝆕", re, im);
var duration = Math.Round((double)Fs / Wav._hz, 5);
Debug.Assert((int)(duration * Wav._hz) == Fs);
double scale = 1.6;
it.Score.Re = scale * duration;
for (int j = 0; j < CBOW.DIMS; j++)
{
RunSpeachFrequencyFilters(it, j);
}
Model[i] = it;
}
return(Model);
}
static Vector CreateMidiVector(Complex[] fft)
{
int N = fft.Length * 2;
Debug.Assert(N == 1024);
double[] im = new double[128];
Vector vec = new Vector("𝅘𝅥𝅮", null, im);
var duration = Math.Round(
(double)N / Wav._hz, 5);
Debug.Assert((int)(duration * Wav._hz) == N);
vec.Score.Re = duration;
vec.Score.Im = N;
for (int i = 0; i < fft.Length; i++)
{
double h = Wav._hz / (double)N,
f = i * h;
double vol = fft[i].Abs();
var m = Envelopes.FREQ2MIDI(f);
if (m >= 0 && m < vec.Axis.Length && vol > 1E-3)
{
vec.Axis[m].Re += vol;
vec.Axis[m].Im += 1;
}
}
for (int m = 0; m < vec.Axis.Length; m++)
{
if (vec.Axis[m].Im == 0)
{
vec.Axis[m].Re = 0;
}
else
{
vec.Axis[m].Re /= vec.Axis[m].Im;
}
vec.Axis[m].Im = Envelopes.MIDI2FREQ(m);
Debug.Assert(Envelopes.FREQ2MIDI(vec.Axis[m].Im) == m);
}
Debug.Assert(vec.Axis[69].Im == 440);
return(vec);
}
static Vector MelFromFourier(Complex[] STFT)
{
int Fs = STFT.Length * 2;
Debug.Assert(Fs == 1024 * 2);
double[] re = new double[CBOW.DIMS],
im = new double[CBOW.DIMS],
cc = new double[CBOW.DIMS];
for (int i = 0; i < STFT.Length; i++)
{
double h = Wav._hz / (double)Fs,
f = i * h;
var m = Envelopes.FREQ2MIDI(f);
Debug.Assert(m == Envelopes.FREQ2MIDI(Envelopes.MIDI2FREQ(m)));
if (m >= 0 && m < CBOW.DIMS)
{
re[m] += STFT[i].Abs();
cc[m] += +1;
}
}
for (int m = 0; m < CBOW.DIMS; m++)
{
// Normalize
if (cc[m] > 0)
{
re[m] /= cc[m];
}
im[m] = Envelopes.MIDI2FREQ(m);
}
Vector it = new Vector("𝆕", re, im);
var duration = Math.Round((double)Fs / Wav._hz, 5);
Debug.Assert((int)(duration * Wav._hz) == Fs);
double scale = 1.6;
it.Score.Re = scale * duration;
return(it);
}
