public FilterSampleProvider(uint filterHalfLength)
{
InputSampleProvider = new DCSampleProvider();
CornerFrequency = 440d;
filterCoefficients = new float[filterHalfLength];
inputBuffer = new float[0];
inputCircleBuffer = new CircleBuffer(2 * filterHalfLength);
// Generate filter coefficients
//int center = filterLength / 2;
for (int i = 0; i < filterCoefficients.Length; i++)
{
//filterCoefficients[i] = (float)Math.Pow(0.5d, i + 1d); // Some BS
// Approximate all-pass filter
//filterCoefficients[i] = i == (filterCoefficients.Length - 1) ? 0.5f : 0f;
// TODO Fix this half-remembered nonsense
/*double phase = (i - center) / (double)SampleRate;
* double x = 2 * Math.PI * phase * cornerFrequency;
* filterCoefficients[i] = x != 0d ? (float)(Math.Sin(x) / x) : 1f;*/
double phase = (i - (filterCoefficients.Length - 0.5d)) / 44100d;
double x = 2 * Math.PI * phase * cornerFrequency;
filterCoefficients[i] = 0.5f * (x != 0d ? (float)(Math.Sin(x) / x) : 0f);
// TODO Apply (real) window function
filterCoefficients[i] *= Math.Min(1f, i * 10f / filterCoefficients.Length);
}
}
public EchoSampleProvider()
{
inputBuffer = new float[0];
echoCircleBuffer = new CircleBuffer((uint)SampleRate);
InputSampleProvider = new DCSampleProvider();
Delay = 0.5f;
Amplitude = 0.5f;
}
public ModulatedSineWaveProvider()
{
waveTable = new float[SampleRate];
for (int i = 0; i < SampleRate; i++)
{
waveTable[i] = (float)Math.Sin(2 * Math.PI * i / SampleRate);
//waveTable[i] = 2f * ((float)i / sampleRate) - 1f; // Sawtooth
}
modulationBuffer = new float[0];
Frequency = 440d;
ModulationSampleProvider = new DCSampleProvider();
SaveResetData();
}
