static void onDrawMicWave(Surface2D Canvas, float phase, Mic32 mic)
{
int m = 10,
samples = (int)Math.Pow(2, m);
Canvas.Fill(Canvas._bgColor);
var data = mic.CH1();
Debug.Assert(data.Length == samples);
int linear(float val, float from, float to)
{
return((int)(val * to / from));
}
Canvas.Line((x, width) => Color.FromArgb(60, 60, 60), (x, width) => {
int i = linear(x, width, data.Length);
return(data[i]);
});
Canvas.Line((x, width) => Color.Orange, (x, width) => {
int i = linear(x, width, data.Length);
return(SigQ.f(Shapes.Harris(i, data.Length)
* data[i]) - 0.5);
});
double duration
= Math.Round(samples / (double)mic.Hz, 4);
Canvas.TopLeft = $"{samples} @ {mic.Hz}Hz = {duration}s";
Canvas.TopRight = $"{phase:N3}s";
}
/*
* static void onDrawMicMidi(Surface2D Canvas, float phase, Mic32 mic) {
* Canvas.Fill(Canvas._bgColor);
*
* var data = mic.ReadData();
*
* int samples = mic.Samples;
*
* double h = Math.Round(mic.Hz
* / (double)samples, 3);
*
* double Nyquis =
* ((samples / 2)) * h;
*
* Debug.Assert(data.Length == samples);
*
* int linear(float val, float from, float to) {
* return (int)(val * to / from);
* }
*
* float[] re = new float[samples],
* im = new float[samples];
*
* for (int i = 0; i < samples; i++) {
* var envelope
* = Shapes.Hann(i, samples);
* re[i] = (float)(data[i].CH1 * envelope);
* }
*
* Complex.FastFourierTransform(
* re,
* im,
+1);
*
* float max = 0;
*
* for (int i = 0; i < samples; i++) {
* re[i] = (float)Math.Sqrt((re[i] * re[i]) + (im[i] * im[i]));
* max = Math.Max(max,
* re[i]);
* }
*
* im = null;
*
* if (max > 0) {
* max = 1 / max;
* }
*
* for (int i = 0; i < samples; i++) {
* re[i] = re[i] * max;
* }
*
* double[] scale = new double[128],
* cc = new double[128];
*
* for (int s = 0; s < samples / 2; s++) {
* var f = (s + 1) * h;
* var p = System.Audio.Midi.FreqToKey(f);
* if (p >= 0 && p < scale.Length) {
* scale[p] += re[s];
* cc[p] += 1;
* }
* }
*
* for (int p = 0; p < scale.Length; p++) {
* if (cc[p] > 0) {
* scale[p] /= cc[p];
* }
* }
*
* double duration
* = Math.Round(samples / (double)mic.Hz, 4);
* int gg = 0;
* for (int p = 0; p < scale.Length; p++) {
* if (scale[p] > 0) {
* if (gg == 0) {
* Console.Write($"{duration}s");
* }
* Console.Write($" {System.Audio.Midi.KeyToTone(p)}");
* var dB = Frequency.dB(scale[p]);
* if (dB < 0) {
* Console.Write($"-{Math.Abs(dB)}dB");
* } else if (dB > 0) {
* Console.Write($"+{dB}dB");
* } else if (dB == 0) {
* Console.Write($"±0");
* }
* gg++;
* }
* }
* if (gg > 0) {
* Console.WriteLine();
* }
*
* Canvas.Line(
* (x, width) => Color.Orange,
* (x, width) => SigQ.f(scale[linear(x, width, scale.Length)]) - 0.5, true
* );
*
* Canvas.TopLeft = $"{samples} @ {mic.Hz}Hz = {duration}s";
* Canvas.TopRight = $"{phase:N3}s";
*
* Canvas.BottomLeft = $"{System.Audio.Midi.KeyToFreq(0)}Hz";
* Canvas.BottomRight = $"{System.Audio.Midi.KeyToFreq(scale.Length-1)}Hz";
* }
*
* static void onDrawMicFastFourierTransformPure(Surface2D Canvas, float phase, Mic32 mic) {
* int samples = mic.Samples;
*
* double h = Math.Round(mic.Hz
* / (double)samples, 3);
*
* double Nyquis =
* ((samples / 2)) * h;
*
* Canvas.Fill(Canvas._bgColor);
*
* var data = mic.ReadData();
*
* Debug.Assert(data.Length == samples);
*
* int linear(float val, float from, float to) {
* return (int)(val * to / from);
* }
*
* float[] re = new float[samples];
* float[] im = new float[samples];
*
* for (int i = 0; i < samples; i++) {
* var envelope
* = Shapes.Hann(i, samples);
*
* re[i] = (float)(data[i].CH1 * envelope);
* }
*
* Complex.FastFourierTransform(
* re,
* im,
+1);
*
* double reNorm = 0;
*
* for (int i = 0; i < samples; i++) {
* re[i] = (float)Math.Sqrt((re[i] * re[i]) + (im[i] * im[i]));
*
* reNorm = Math.Max(reNorm,
* re[i]);
* }
*
* if (reNorm > 0) {
* reNorm = 1 / reNorm;
* }
*
* for (int i = 0; i < samples; i++) {
* re[i] = (float)(re[i] * reNorm);
* }
*
* Canvas.Line(
* (x, width) => Color.Orange,
* (x, width) => SigQ.f(re[linear(x, width, samples / 2)]) - 0.5, true
* );
* Canvas.Line(
* (x, width) => Color.Gray,
* (x, width) => -(SigQ.f(re[linear(x, width, samples / 2)]) - 0.5), true
* );
*
* double duration
* = Math.Round(samples / (double)mic.Hz, 4);
*
* Canvas.TopLeft = $"{samples} @ {mic.Hz}Hz = {duration}s";
* Canvas.TopRight = $"{phase:N3}s";
*
* Canvas.BottomLeft = $"{h}Hz";
* Canvas.BottomRight = $"{Nyquis}Hz";
* }
*/
static void onDrawMicFastFourierTransform(Surface2D Canvas, float phase, Mic32 mic)
{
int samples = mic.Samples;
double h = Math.Round(mic.Hz
/ (double)samples, 3);
double Nyquis =
((samples / 2)) * h;
Canvas.Fill(Canvas._bgColor);
var ch1 = mic.CH1();
Debug.Assert(ch1.Length == samples);
int linear(float val, float from, float to)
{
return((int)(val * to / from));
}
Func <int, int, double> envelope = null;
var fft = new Complex[samples];
for (int s = 0; s < samples; s++)
{
float A = envelope != null
? (float)envelope(s, samples)
: 1.0f;
fft[s].Re = A *
ch1[s];
}
Complex.FastFourierTransform(
fft,
+1);
// double reNorm = 0;
//
// for (int i = 0; i < samples; i++) {
// re[i] = (float)Math.Sqrt((re[i] * re[i]) + (im[i] * im[i]));
//
// reNorm = Math.Max(reNorm,
// re[i]);
// }
//
// if (reNorm > 0) {
// reNorm = 1 / reNorm;
// }
//
// for (int i = 0; i < samples; i++) {
// re[i] = (float)(re[i] * reNorm);
// }
Canvas.Line(
(x, width) => Color.Orange,
(x, width) => SigQ.f(fft[linear(x, width, samples / 2)].Magnitude) - 0.5, true
);
Canvas.Line(
(x, width) => Color.Gray,
(x, width) => - (SigQ.f(fft[linear(x, width, samples / 2)].Magnitude) - 0.5), true
);
double duration
= Math.Round(samples / (double)mic.Hz, 4);
Canvas.TopLeft = $"{samples} @ {mic.Hz}Hz = {duration}s";
Canvas.TopRight = $"{phase:N3}s";
Canvas.BottomLeft = $"{h}Hz";
Canvas.BottomRight = $"{Nyquis}Hz";
}
