public void CompareConvolveMethods()
{
const int signalLength = 32000;
const int filterLength = 128;
//Creates signal and filter by sine wave
var signalBlock = new GenerateSignalBlock {
TemplateName = "Sine", Start = 0, Finish = 1, SamplingRate = signalLength, IgnoreLastSample = true
};
signalBlock.Execute();
var signal = signalBlock.OutputNodes[0].Object[0].Samples;
var filter = new double[filterLength];
Array.Copy(signal, filter, filterLength);
//Run Normal convolution and show time
var stopWatch = new System.Diagnostics.Stopwatch();
stopWatch.Start();
var convolvedNormal = WaveMath.ConvolveNormal(signal, filter);
stopWatch.Stop();
Console.WriteLine("Normal Convolve {0} samples - {1} ms", convolvedNormal.Length, stopWatch.ElapsedMilliseconds);
//Run ManagedFFT convolution and show time
WaveMath.ConvolveManagedFFT(signal, filter);
stopWatch.Reset();
stopWatch.Start();
var convolvedFFT = WaveMath.ConvolveManagedFFT(signal, filter);
stopWatch.Stop();
Console.WriteLine("FFT Convolve {0} samples - {1} ms", convolvedFFT.Length, stopWatch.ElapsedMilliseconds);
}
public void TestConvolve()
{
var signal = new double[] { 1, 2, 3, 4, 5, 6, 7, 8 };
var filter = new double[] { 1, 2, 3 };
var convolved = WaveMath.Convolve(ConvolutionModeEnum.Normal, signal, filter);
var expected = new double[] { 10, 16, 22, 28, 34, 40 };
Assert.IsTrue(convolved.SequenceEqual(expected));
signal = new double[] { 1, 2, 3 };
filter = new double[] { 1, 2, 3, 4, 5 };
convolved = WaveMath.ConvolveNormal(signal, filter);
expected = new double[] { 10, 16, 22 };
Assert.IsTrue(convolved.SequenceEqual(expected));
signal = new double[] { 1, 2, 3, 4, 5, 6, 7, 8 };
filter = new double[] { 1, 2, 3, 4 };
convolved = WaveMath.ConvolveNormal(signal, filter, false);
expected = new double[] { 1, 4, 10, 20, 30, 40, 50, 60, 61, 52, 32 };
Assert.IsTrue(convolved.SequenceEqual(expected));
}