private void FilterWithFiniteImpluseResponseInTheTimeDomain(object o)
{
Stopwatch sw = new Stopwatch();
sw.Start();
try
{
int L = int.Parse(this.FilterLength);
int Fc = int.Parse(this.CutoffFrequency);
int Fs = this.SampleRate;
double[] filter = FilterWithFiniteImpulseResponse.GetFilterValues(Fc, Fs, L);
double[] filtered = FourierWindows.MultiplyByWindowFunction(filter, this.SelectedWindowType);
double[] result = FilterWithFiniteImpulseResponse.FilterInTheTimeDomain(this.SignalData.Samples, filtered, L);
this.FilterResultInTheTimeDomain = result;
}
catch (Exception e)
{
Notify.Error(e.Message);
}
sw.Stop();
this.FilterTimeInTheTimeDomain = sw.ElapsedMilliseconds.ToString();
}
private void FilterWithFiniteImpluseResponseInTheFrequencyDomain(object o)
{
Stopwatch sw = new Stopwatch();
sw.Start();
try
{
int L = int.Parse(this.FilterLength);
int Fc = int.Parse(this.CutoffFrequency);
int Fs = this.SampleRate;
int R = int.Parse(this.HopSize);
int M = int.Parse(this.WindowSize);
int n = GetExpandedPow2(M + L - 1);
int size = this.SignalData.Samples.Length + n - L;
double[] result = new double[size];
double[][] windows = new double[size / R][];
Complex[][] windowsComplex = new Complex[size / R][];
for (int i = 0; i < windows.Length; i++)
{
windows[i] = new double[n];
windowsComplex[i] = new Complex[n];
}
double[] windowFactors = FourierWindows.GetWindowFactors(M, this.SelectedWindowType);
for (int i = 0; i < windows.Length; i++)
{
for (int j = 0; j < M; j++)
{
if (i * R + j < this.SignalData.Samples.Length)
{
windows[i][j] = windowFactors[j] * this.SignalData.Samples[i * R + j];
}
else
{
windows[i][j] = 0;
}
}
for (int j = M; j < n; j++)
{
windows[i][j] = 0;
}
}
double[] windowFilterFactors = FourierWindows.GetWindowFactors(L, this.SelectedWindowType);
double[] filterFactors = FilterWithFiniteImpulseResponse.GetFilterValues(Fc, Fs, L);
double[] filtered = new double[n];
for (int i = 0; i < L; i++)
{
filtered[i] = windowFilterFactors[i] * filterFactors[i];
}
for (int i = L; i < n; i++)
{
filtered[i] = 0;
}
if (this.SelectedZeroFillingMethod == ZeroFillingMethod.CauselessFilter)
{
int shiftNumberFilter = (L - 1) / 2;
IEnumerable <double> shiftedFilter = filtered.Take(shiftNumberFilter);
List <double> filteredTemp = filtered.Skip(shiftNumberFilter).ToList();
filteredTemp.AddRange(shiftedFilter);
filtered = filteredTemp.ToArray();
}
Complex[] filteredComplex = FourierTransform.FFT(filtered);
for (int i = 0; i < windows.Length; i++)
{
windowsComplex[i] = FourierTransform.FFT(windows[i]);
for (int j = 0; j < windowsComplex[i].Length; j++)
{
windowsComplex[i][j] *= filteredComplex[j];
}
windows[i] = FourierTransform.IFFT(windowsComplex[i]);
}
for (int i = 0; i < windows.Length; i++)
{
for (int j = 0; j < windows[i].Length; j++)
{
if (i * R + j < this.SignalData.Samples.Length)
{
result[i * R + j] += windows[i][j];
}
}
}
this.FilterResultInTheFrequencyDomain = result;
}
catch (Exception e)
{
Notify.Error(e.Message);
}
sw.Stop();
this.FilterTimeInTheFrequencyDomain = sw.ElapsedMilliseconds.ToString();
}
