static void RunSpeachFrequencyFilters(Vector it, int j, double vol = 0.01, int dbMin = -20, int dbMax = +20)
{
bool IsAudible(double f)
{
if ((f >= 8.1 && f <= 16743.9))
{
return(true);
}
return(false);
}
bool pass = true;
if (!IsAudible(it.Axis[j].Im))
{
pass = false;
}
if (it.Axis[j].Re <= 0.01)
{
pass = false;
}
if (pass)
{
var n = Envelopes.MIDI2NOTE(Envelopes.FREQ2MIDI(it.Axis[j].Im));
if (string.IsNullOrWhiteSpace(n))
{
pass = false;
}
if (n == null || (!n.Contains("3") && !n.Contains("4") && !n.Contains("5") &&
!n.Contains("6")))
{
pass = false;
}
if (pass && it.Axis[j].Re > 0)
{
var dB = Envelopes.dB(it.Axis[j].Re);
if (dB <= dbMin || dB >= dbMax)
{
pass = false;
}
}
}
if (!pass)
{
it.Axis[j].Re = 0;
}
}
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 void RunSpeachFrequencyFilters(Vector vec, int j)
{
bool IsAudible(double f)
{
if ((f >= 8.1 && f <= 16743.9))
{
return(true);
}
return(false);
}
if (!IsAudible(vec.Axis[j].Im))
{
vec.Axis[j].Re = 0;
}
var n = Envelopes.MIDI2NOTE(Envelopes.FREQ2MIDI(vec.Axis[j].Im));
if (string.IsNullOrWhiteSpace(n)
// || n.Contains("#")
// || n.Contains("0")
// || n.Contains("1")
// || n.Contains("2")
// || n.Contains("3")
// || n.Contains("4")
// || n.Contains("5")
// || n == "C6"
// || n == "E6"
// || n == "D6"
// || n == "A6"
// || n == "F6"
// || n == "G6"
// || n == "B6"
// || n.Contains("7")
// || n.Contains("8")
// || n.Contains("9")
)
{
vec.Axis[j].Re = 0;
}
}
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);
}
static void ParseNotes(Matrix Model, string sl, int dims)
{
int i = 0, wordStart = i;
while (i < sl.Length && (sl[i] == '\t' || sl[i] == ' ' ||
sl[i] == '•' || sl[i] == '|' || sl[i] == '⁞'))
{
i++;
}
Vector vec;
int t = Model.Count;
if (t >= Model.Capacity)
{
throw new OutOfMemoryException();
}
vec = new Vector("𝆕");
if (vec.Axis == null)
{
vec.Axis = new Complex[dims];
}
Model[t] = vec;
for (; ;)
{
wordStart = i;
while (i < sl.Length && (sl[i] == '±' || sl[i] == '-' || sl[i] == '+' || sl[i] == 'E' ||
sl[i] == 'A' || sl[i] == 'B' || sl[i] == 'C' ||
sl[i] == 'D' || sl[i] == 'F' || sl[i] == 'G' ||
sl[i] == '#' ||
sl[i] == '.' || char.IsDigit(sl[i])))
{
i++;
}
var ImSign = +1;
int len = (i - wordStart) - 1;
while (wordStart + len > 0 && wordStart + len < sl.Length &&
(sl[wordStart + len] == '-' || sl[wordStart + len] == '+' || sl[wordStart + len] == '±'))
{
if (sl[wordStart + len] == '-')
{
ImSign = -1;
}
len--;
}
string Re = sl.Substring(wordStart, len + 1);
string Im = null;
if (i < sl.Length && (sl[i] == 'i'))
{
i++;
wordStart = i;
while (i < sl.Length && (sl[i] == '-' || sl[i] == '+' || sl[i] == 'E' ||
sl[i] == 'A' || sl[i] == 'B' || sl[i] == 'C' ||
sl[i] == 'D' || sl[i] == 'F' || sl[i] == 'G' ||
sl[i] == '#' ||
sl[i] == '.' || char.IsDigit(sl[i])))
{
i++;
}
Im = sl.Substring(wordStart, i - wordStart);
}
if (!string.IsNullOrWhiteSpace(Re))
{
var f = Envelopes.NOTE2FREQ(Re);
int m = Envelopes.FREQ2MIDI(f);
if (m >= 0 && m < vec.Axis.Length)
{
vec.Axis[m].Im = f;
vec.Axis[m].Re = 1;
if (!string.IsNullOrWhiteSpace(Im))
{
vec.Axis[m].Re = Envelopes.Amplitude((int)(ImSign * double.Parse(Im)));
}
}
while (i < sl.Length && (sl[i] == '\t' || sl[i] == ' ' || sl[i] == '•' || sl[i] == '|' || sl[i] == '⁞'))
{
i++;
}
}
else /* End of Line */
{
break;
}
}
}
public static Matrix ShortTimeFourierTransform(Complex[] sig, Set filter, double vol = 0.01, int dbMin = -20, int dbMax = +20)
{
Console.Write($"\r\nBuilding a new Mel model...\r\n");
double norm = 0.0,
cc = 0;
var Model = new Matrix((int)Math.Ceiling(sig.Length / (double)2048));
foreach (var STFT in Complex.ShortTimeFourierTransform(sig))
{
int i = Model.Count;
if (i >= Model.Capacity)
{
throw new OutOfMemoryException();
}
Vector it;
Debug.Assert(Model[i] == null);
Model[i] = it = MelFromFourier(STFT);
for (var j = 0; j < it.Axis.Length; j++)
{
norm += it.Axis[j].Re;
cc++;
}
}
if (cc > 0)
{
norm = norm /= cc;
if (norm > 0)
{
norm = 1d / norm;
}
}
for (int i = 0; i < Model.Count; i++)
{
var it = Model[i];
if (it != null)
{
for (var j = 0; j < it.Axis.Length; j++)
{
it.Axis[j].Re = Math.Round(norm
/* Note that this surface is really wierd... i.e. There are
* positive and negative decibeles */
* it.Axis[j].Re / (it.Axis.Length * 0.1), 3);
it.Axis[j].Re = it.Axis[j].Re;
if (it.Axis[j].Re > 0)
{
RunSpeachFrequencyFilters(it, j, vol, dbMin, dbMax);
}
if (it.Axis[j].Re > 0 && filter != null)
{
/* Filter out the specified pitches */
var n = Envelopes.MIDI2NOTE(Envelopes.FREQ2MIDI(it.Axis[j].Im));
if (string.IsNullOrWhiteSpace(n) || filter.Has(n))
{
it.Axis[j].Re = 0;
}
}
double finalMag = Math.Round(it.Axis[j].Re, 2);
it.Axis[j].Re
= finalMag;
}
double dot = 0.0;
for (var j = 0; j < it.Axis.Length; j++)
{
dot += it.Axis[j].Re * 1;
}
it.Score.Im = Math.Round(
Tanh.f(dot), 2);
}
}
return(Model);
}