public static Complex[] Dft(Complex[] signal, uint samplingRation, HammingWindowDef hammingWindow = null)
{
var signalLength = signal.Length;
var ret = new Complex[signalLength];
var phasePart = -2 * Math.PI / signalLength;
var phaseHammingPart = 2 * Math.PI / (signalLength - 1);
for (int frequency = 0; frequency < signalLength; frequency++)
{
ret[frequency] = new Complex();
var phasePartFrequency = phasePart * frequency;
for (int step = 1; step <= signal.Length; step++)
{
var phase = phasePartFrequency * (step);
var temp = signal[step - 1] * Complex.FromPolarCoordinates(1, phase);
if (hammingWindow != null)
{
temp = temp * (hammingWindow.Alpha - hammingWindow.Beta * Math.Cos(phaseHammingPart * (step)));
}
ret[frequency] += temp;
}
}
return ret;
}
public static double[] ApplyHammingWindow(float[] signal, HammingWindowDef hammingWindowDef = null)
{
if (hammingWindowDef == null)
{
hammingWindowDef = new HammingWindowDef();
}
var hammingWindow = new HammingWindow(hammingWindowDef, signal.Length);
return hammingWindow.Apply(signal);
}
public HammingWindow(HammingWindowDef definition, int signalLength)
{
var phaseHammingPart = 2 * Math.PI / (signalLength - 1);
var definition1 = definition;
_values = new double[signalLength];
for (int index = 0; index < signalLength; index++)
{
_values[index] = definition1.Alpha - (definition1.Beta * Math.Cos(phaseHammingPart * index));
}
}
public void TestHamming()
{
var hamming = new HammingWindowDef();
var hammingWindow = new HammingWindowDef.HammingWindow(hamming, 5);
var ret = new double[5];
for (var index = 0; index < 5; index++)
{
ret[index] = hammingWindow[index];
}
}