public void Should_correctly_process_multiple_channels()
{
var buffers = new float[][] { new float[4], new float[4] };
var expected = new float[]
{
5f, 6f, 7f, 8f
};
transformProvider.FFT(Arg.Any<bool>(), Arg.Any<int>(), Arg.Do<Complex[]>(x =>
{
x[0] = new Complex { X = expected[0], Y = 0f };
x[1] = new Complex { X = expected[1], Y = 0f };
x[2] = new Complex { X = expected[2], Y = 0f };
x[3] = new Complex { X = expected[3], Y = 0f };
}));
target = new FourierTransform(transformProvider, windowFunction, 4);
float[][] actual = new float[2][];
target.DataReady += (s, e) => actual[e.Channel] = e.Real;
target.Format = new WaveFormat(44100, 2);
target.Process(buffers, 4);
CollectionAssert.AreEqual(expected, actual[0], new FloatComparer());
CollectionAssert.AreEqual(expected, actual[1], new FloatComparer());
}
private void BuildAudioInChain(WaveFormat monoFormat)
{
filter = new ComplexFilter(
monoFormat,
new BlackmanHarrisWindowFunction(),
new FirFilter());
filter.Filters.Add(new DigitalFilter
{
FilterFunction = new LowPassFilterFunction(),
LowerCutOffFrequency = 10000f
});
filterNode = new MonoSignalNode(monoFormat, filter.FilterImplementation);
fourier = new FourierTransform(
new FastFourierTransformProvider(),
new BlackmanHarrisWindowFunction(),
2048);
fourierNode = new MonoSignalNode(monoFormat, fourier);
fourier.DataReady += fourierControl.fourier_DataReady;
flanger = new Flanger(new SineWave());
flangerNode = new MonoSignalNode(monoFormat, flanger);
flangerNode.CentreIn.Source = asioInput.Sources.First();
//flangerNode.CentreIn.Source = waveCard.Inputs.First();
filterNode.CentreIn.Source = flangerNode.CentreOut;
fourierNode.CentreIn.Source = filterNode.CentreOut;
asioOutput.Sinks.ElementAt(0).Source = filterNode.CentreOut;
asioOutput.Sinks.ElementAt(1).Source = filterNode.CentreOut;
//waveCard.Outputs.ElementAt(0).Source = filterNode.CentreOut;
//waveCard.Outputs.ElementAt(1).Source = filterNode.CentreOut;
}
public void FourierTransform_16384_length_2000000_iterations()
{
var transformProvider = new ProviderFake();
var windowFunction = new BlackmanHarrisWindowFunction();
var target = new FourierTransform(
transformProvider,
windowFunction,
4096 * 4);
target.Format = new WaveFormat(44100, 1);
var buffers = new float[][] { new float[64] };
for (int i = 0; i < 2000000; i++)
{
target.Process(buffers, 64);
}
}
public void Should_apply_window_function_to_FFT_inputs()
{
var buffers = new float[][]{ new []
{
1f, 2f, 3f, 4f
}};
windowFunction.CalculateCoefficients(Arg.Is(4))
.Returns(new[] { 5f, 6f, 7f, 8f });
target = new FourierTransform(transformProvider, windowFunction, 4);
target.Format = new WaveFormat(44100, 1);
target.Process(buffers, 4);
transformProvider.Received(1).FFT(
Arg.Any<bool>(),
Arg.Any<int>(),
Arg.Is<Complex[]>(x => x.Length == 4
&& x[0].X == 5f
&& x[1].X == 12f
&& x[2].X == 21f
&& x[3].X == 32f));
}
private void BuildSineWaveChain(WaveFormat stereoFormat)
{
sineWave = new SineWave();
sineWaveNode = new StereoSignalNode(stereoFormat, sineWave);
sineWaveNode.LeftIn.Source = asioInput.Sources.ElementAt(0);
sineWaveNode.RightIn.Source = asioInput.Sources.ElementAt(0);
filter = new ComplexFilter(
stereoFormat,
new BlackmanHarrisWindowFunction(),
new FirFilter());
filter.Filters.Add(new DigitalFilter
{
FilterFunction = new BandStopFilterFunction(),
LowerCutOffFrequency = 10000f,
UpperCutOffFrequency = 12000f
});
stereoFilterNode = new StereoSignalNode(stereoFormat, filter.FilterImplementation);
stereoFilterNode.LeftIn.Source = sineWaveNode.LeftOut;
stereoFilterNode.RightIn.Source = sineWaveNode.RightOut;
fourier = new FourierTransform(
new FastFourierTransformProvider(),
new BlackmanHarrisWindowFunction(),
2048);
fourierNode = new MonoSignalNode(stereoFormat, fourier);
fourier.DataReady += fourierControl.fourier_DataReady;
fourierNode.CentreIn.Source = stereoFilterNode.LeftOut;
asioOutput.Sinks.ElementAt(0).Source = stereoFilterNode.LeftOut;
asioOutput.Sinks.ElementAt(1).Source = stereoFilterNode.RightOut;
}
public void Should_pass_samples_to_FFT_implementation_as_real_component()
{
var buffers = new float[][]{ new []
{
1f, 2f, 3f, 4f
}};
target = new FourierTransform(transformProvider, windowFunction, 4);
target.Format = new WaveFormat(44100, 1);
target.Process(buffers, 4);
transformProvider.Received(1).FFT(
Arg.Any<bool>(),
Arg.Any<int>(),
Arg.Is<Complex[]>(x => x.Length == 4
&& x[0].X == 1f
&& x[1].X == 2f
&& x[2].X == 3f
&& x[3].X == 4f));
}
public void Should_throw_if_window_function_is_null()
{
target = new FourierTransform(transformProvider, null, 1);
}
public void TestInitialise()
{
var ones = new float[100];
for (int i = 0; i < 100; i++)
{
ones[i] = 1f;
}
transformProvider = Substitute.For<IFastFourierTransformProvider>();
windowFunction = Substitute.For<IWindowFunction>();
windowFunction.CalculateCoefficients(Arg.Any<int>()).Returns(ones);
target = new FourierTransform(transformProvider, windowFunction, 1);
target.Format = new WaveFormat(44100, 1);
}
public void Should_throw_if_transform_provider_is_null()
{
target = new FourierTransform(null, windowFunction, 1);
}
public void Should_throw_if_transform_length_is_not_a_power_of_two()
{
target = new FourierTransform(transformProvider, windowFunction, 3);
}
public void Should_provide_the_power_of_two_for_the_transform_length()
{
var buffers = new float[][] { new float[16] };
target = new FourierTransform(transformProvider, windowFunction, 16);
target.Format = new WaveFormat(44100, 1);
target.Process(buffers, 16);
transformProvider.Received(1).FFT(
Arg.Any<bool>(),
Arg.Is<int>(4),
Arg.Any<Complex[]>());
}
public void Should_provide_the_FFT_provider_result_via_the_DataReady_event()
{
var buffers = new float[][] { new float[4] };
var expected = new float[]
{
5f, 6f, 7f, 8f
};
transformProvider.FFT(Arg.Any<bool>(), Arg.Any<int>(), Arg.Do<Complex[]>(x =>
{
x[0] = new Complex { X = expected[0], Y = 0f };
x[1] = new Complex { X = expected[1], Y = 0f };
x[2] = new Complex { X = expected[2], Y = 0f };
x[3] = new Complex { X = expected[3], Y = 0f };
}));
target = new FourierTransform(transformProvider, windowFunction, 4);
float[] actual = null;
target.DataReady += (s, e) => actual = e.Real;
target.Format = new WaveFormat(44100, 1);
target.Process(buffers, 4);
CollectionAssert.AreEqual(expected, actual, new FloatComparer());
}
public void Should_perform_forwards_FFT()
{
var buffers = new float[][] { new float[4] };
target = new FourierTransform(transformProvider, windowFunction, 4);
target.Format = new WaveFormat(44100, 1);
target.Process(buffers, 4);
transformProvider.Received(1).FFT(
Arg.Is<bool>(true),
Arg.Any<int>(),
Arg.Any<Complex[]>());
}
