public BluesteinTransformlet(int R, int N, Complex[] u)
: base(R, N, u)
{
// figure out the right Bluestein length and create a transformer for it
Nb = SetBluesteinLength(2 * R - 1);
ft = new FourierTransformer(Nb);
// compute the Bluestein coeffcients and compute the FT of the filter based on them
b = ComputeBluesteinCoefficients(R);
Complex[] c = new Complex[Nb];
c[0] = 1.0;
for (int i = 1; i < R; i++) {
c[i] = b[i].Conjugate;
c[Nb - i] = c[i];
}
bt = ft.Transform(c);
}
public BluesteinTransformlet(int R, int N, Complex[] u) : base(R, N, u)
{
// figure out the right Bluestein length and create a transformer for it
Nb = SetBluesteinLength(2 * R - 1);
ft = new FourierTransformer(Nb);
// compute the Bluestein coeffcients and compute the FT of the filter based on them
b = ComputeBluesteinCoefficients(R);
Complex[] c = new Complex[Nb];
c[0] = 1.0;
for (int i = 1; i < R; i++)
{
c[i] = b[i].Conjugate;
c[Nb - i] = c[i];
}
bt = ft.Transform(c);
}
public static List<double> AmplitudeFromLR2(int snapsize, double[] l, int i_skip, int i_count, double lowpass = 2.5, Dictionary<int, double> mw = null)
{
FourierTransformer ft = new FourierTransformer(snapsize);
var xxa = new Complex[i_count];
if (mw.Count == i_count)
for (int j = 0; j < i_count; j++)
xxa[j] = new Complex(l[j + i_skip] * mw[j], l[j + i_skip] * mw[j]);
else
return null;
var ftt = ft.Transform(xxa).Take((int)(i_count / (2 * lowpass))); // TAKING ONLY LEFT HALF OF FFT RESULT
List<double> pow_re_im = new List<double>();
//ftt.ToList().ForEach(t => pow_re_im.Add(Math.Log(ComplexMath.Abs(t))));
//ftt.ToList().ForEach(t => pow_re_im.Add(Math.Sqrt(Math.Max(Math.Log(ComplexMath.Abs(t)),0))));
ftt.ToList().ForEach(t => pow_re_im.Add(Math.Pow(Math.Max(Math.Log(ComplexMath.Abs(t)), 0), 2)));
return pow_re_im;
}
public bool MakeSnaps(int _snapsize, int _snapcount, string _path, int smooth_size)
{
try
{
using (Mp3FileReader pcm = new Mp3FileReader(_path))
{
int samplesDesired = _snapsize;
int blockscount = _snapcount;
snap_size = _snapsize;
snap_count = _snapcount;
total_samples = pcm.Length;
length = pcm.TotalTime.Seconds;
path = _path;
if ((pcm.WaveFormat.SampleRate != 44100) || (pcm.WaveFormat.BitsPerSample != 16))
return false;
for (int i = 0; i < blockscount; i++)
{
byte[] buffer = new byte[samplesDesired * 4];
short[] left = new short[samplesDesired];
short[] right = new short[samplesDesired];
double[] leftd = new double[samplesDesired];
double[] rightd = new double[samplesDesired];
int bytesRead = 0;
//for (int j = 0; j < 1; j++) ///////////
int seek_counter = 0;
seek: pcm.Seek((i + 1) * (i + 1) * (i + 1) * blockscount * samplesDesired % (total_samples - samplesDesired), SeekOrigin.Begin);
seek_counter++;
bytesRead = pcm.Read(buffer, 0, 4 * samplesDesired);
int index = 0;
for (int sample = 0; sample < bytesRead / 4; sample++)
{
left[sample] = BitConverter.ToInt16(buffer, index); index += 2;
right[sample] = BitConverter.ToInt16(buffer, index); index += 2;
}
if (left.Average(t => Math.Abs(t)) == 0)
if (seek_counter > 5)
return false;
else
goto seek;
//snap_log10_energy.Add(Math.Log10(left.Average(t => Math.Abs(t))));
leftd = Normalize(left, left.Length);
rightd = Normalize(right, right.Length);
//alglib.complex[] fl;
//alglib.fftr1d(leftd, out fl);
//fl[0].x;
FourierTransformer ft = new FourierTransformer(samplesDesired);
var xxa = new Complex[leftd.Length];
for (int j = 0; j < leftd.Length; j++)
xxa[j] = new Complex(leftd[j], rightd[j]);
var ftt = ft.Transform(xxa);
List<double> pow_re_im = new List<double>();
//List<double> arg_re_im = new List<double>();
ftt.ToList().ForEach(t => pow_re_im.Add(ComplexMath.Abs(t)));
//ftt.ToList().ForEach(t => arg_re_im.Add(ComplexMath.Arg(t)));
/*if (Double.IsNaN(MC_Log10_Energy(pow_re_im)))
if (seek_counter > 5)
return false;
else
goto seek;*/
fft_snaps.Add(pow_re_im);
//fft_smoothed_snaps.Add(Smoothen(pow_re_im, smooth_size));
//pow_re_im = Normalize(pow_re_im);
/*
var f_pwri = pow_re_im.Average(t => Math.Abs(t));
for (int k = 0; k < pow_re_im.Count; k++)
pow_re_im[k] = (Math.Abs(pow_re_im[k]) >= f_pwri * 1.5) ? pow_re_im[k] : 0;
*/
/*
FourierTransformer ft2 = new FourierTransformer(samplesDesired);
var xx2 = new List<Complex>();
for (int j = 0; j < pow_re_im.Count; j++)
{
xx2.Add(new Complex(pow_re_im[j], arg_re_im[j]));
}
var ftt2 = ft2.Transform(xx2);
//var ftt2 = ft2.Transform(ftt);
List<double> pow_re_im2 = new List<double>();
ftt2.ToList().ForEach(t => pow_re_im2.Add(ComplexMath.Abs(t)));
pow_re_im2 = Normalize(pow_re_im2);
fft2_snaps.Add(pow_re_im2);
fft2_smoothed_snaps.Add(Smoothen(pow_re_im2, smooth_size));
*/
}
pcm.Close();
}
}
catch (Exception e)
{
return false;
}
return true;
}