public void CheckWithDelayFilter()
{
var channelCount = 3;
var impulseResponses = new double[][]
{
new double[] { 0.0, 0.0, 0.0, 1.0 },
new double[] { 0.0, 0.0, 1.0 },
new double[] { 0.0, 0.0, 0.0, 0.0, 1.0 }
};
var delaySampleCounts = new int[]
{
3,
2,
4
};
var dftLength = 1024;
var sv = SteeringVector.FromImpulseResponse(impulseResponses, dftLength);
Assert.AreEqual(dftLength / 2 + 1, sv.Length);
for (var ch = 0; ch < channelCount; ch++)
{
var expected = Filtering.CreateFrequencyDomainDelayFilter(dftLength, delaySampleCounts[ch]);
for (var w = 0; w < dftLength / 2 + 1; w++)
{
Assert.AreEqual(expected[w].Real, sv[w][ch].Real, 1.0E-6);
Assert.AreEqual(expected[w].Imaginary, sv[w][ch].Imaginary, 1.0E-6);
}
}
}
public void CheckWithDelayFilter_Case2()
{
var delaySampleCount = 3;
var sampleRate = 16000;
var dftLength = 1024;
var time = (double)delaySampleCount / sampleRate;
var distance = AcousticConstants.SoundSpeed * time;
var soundSource = new SoundSource(1.0, 1.0, 1.0);
var microphones = new Microphone[]
{
new Microphone(1.0 + 1 * distance, 1.0, 1.0),
new Microphone(1.0 + 2 * distance, 1.0, 1.0),
new Microphone(1.0 + 3 * distance, 1.0, 1.0)
};
var sv = SteeringVector.FromFarFieldGeometry(microphones, Math.PI / 4, 0.0, sampleRate, dftLength);
Assert.AreEqual(dftLength / 2 + 1, sv.Length);
var delayFilters = new Complex[][]
{
Filtering.CreateFrequencyDomainDelayFilter(dftLength, 0 / Math.Sqrt(2)),
Filtering.CreateFrequencyDomainDelayFilter(dftLength, 3 / Math.Sqrt(2)),
Filtering.CreateFrequencyDomainDelayFilter(dftLength, 6 / Math.Sqrt(2))
};
for (var w = 0; w < dftLength / 2 + 1; w++)
{
for (var ch = 0; ch < 3; ch++)
{
var actual = sv[w][ch];
var expected = delayFilters[ch][w];
Assert.AreEqual(expected.Real, actual.Real, 1.0E-6);
Assert.AreEqual(expected.Imaginary, actual.Imaginary, 1.0E-6);
}
}
}