public void BinFrequencyList(byte binsPer)
{
const float BASE_FREQ = 55F;
const byte OCTAVES = 5;
ShinNoteFinderDFT NF = new ShinNoteFinderDFT();
NF.OctaveCount = OCTAVES;
NF.BinsPerOctave = binsPer;
NF.CalculateFrequencies(BASE_FREQ);
FieldInfo BinFreq = typeof(ShinNoteFinderDFT).GetField("BinFrequencies", BindingFlags.NonPublic | BindingFlags.Instance);
float[] Value = (float[])BinFreq.GetValue(NF);
// Make sure we have the correct number of frequency bins.
Assert.AreEqual(OCTAVES * binsPer, Value.Length, "Bin count was incorrect");
// Make sure the first bin is the base frequency we set earlier.
Assert.AreEqual(BASE_FREQ, Value[0], "Base frequency was incorrectly set");
float CalcNextOctave = Value[binsPer];
// Make sure the bin 1 octave up is double the base frequency.
Assert.IsTrue(Math.Abs((BASE_FREQ * 2) - CalcNextOctave) < 0.0001F, "Higher frequencies were incorrectly calculated");
}
[DataRow(1174.66F, 106, DisplayName = "D6")] // Top octave
public void OutputBinTestSingleValueWithPureSine(float testFreq, int expectedPeak)
{
const float BASE_FREQ = 55F; // A2
ShinNoteFinderDFT NF = new ShinNoteFinderDFT();
NF.CalculateFrequencies(BASE_FREQ);
NF.FillReferenceTables();
NF.PrepareSampleStorage();
// Fill input.
float Omega1 = testFreq * MathF.PI * 2 / NF.SampleRate;
float[] TestWaveform = new float[NF.WindowSize / 2];
for (uint i = 0; i < TestWaveform.Length; i++)
{
TestWaveform[i] = MathF.Sin(i * Omega1);
}
NF.AddSamples(TestWaveform);
//NF.SaveData();
// Get output
float[] Output = NF.Magnitudes;
// Find peak
float PeakVal = -1F;
int PeakInd = -1;
for (int i = 0; i < Output.Length; i++)
{
if (Output[i] > PeakVal)
{
PeakVal = Output[i];
PeakInd = i;
}
}
// Make sure peak is correct and large enough
Assert.IsTrue(PeakVal > 1500F, "Peak was not large enough");
Assert.IsTrue(PeakInd == expectedPeak, "Peak was in the wrong place");
// Make sure all far-away bins are small enough
for (int i = 0; i < Output.Length; i++)
{
if (Math.Abs(i - PeakInd) > 3)
{
Assert.IsTrue(Output[i] < (PeakVal / 2), "Other frequencies had content too strong compared to peak");
}
}
}
public void CheckOctavePattern()
{
const float BASE_FREQ = 55F; // A2
const float SIGNAL_FREQ = 880F;
const float PHASE_OFFSET = MathF.PI / 4; // Apply a small phase offset so that the signal doesn't start at 0.
ShinNoteFinderDFT NF = new ShinNoteFinderDFT();
NF.CalculateFrequencies(BASE_FREQ);
NF.FillReferenceTables();
NF.PrepareSampleStorage();
float Omega = SIGNAL_FREQ * MathF.PI * 2 / NF.SampleRate;
// Add the first sample, so we should only see content in the topmost octave
NF.AddSample(MathF.Sin((0 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 1) * NF.BinsPerOctave);
// Second sample, now the top two octaves should be calculated.
NF.AddSample(MathF.Sin((1 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 2) * NF.BinsPerOctave);
// Third sample, only the top octave should update
NF.AddSample(MathF.Sin((2 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 2) * NF.BinsPerOctave);
// Fourth sample, the top 3 octaves should all get calculated
NF.AddSample(MathF.Sin((3 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 3) * NF.BinsPerOctave);
// Fifth sample, only top octave
NF.AddSample(MathF.Sin((4 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 3) * NF.BinsPerOctave);
// Sixth sample, top 2 octaves
NF.AddSample(MathF.Sin((5 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 3) * NF.BinsPerOctave);
// Seventh sample, only top
NF.AddSample(MathF.Sin((6 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 3) * NF.BinsPerOctave);
// Eighth sample, top 4 octaves should all be calculated.
NF.AddSample(MathF.Sin((7 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 4) * NF.BinsPerOctave);
// 9th - 15th samples, same pattern, no new octaves yet
for (int i = 8; i < 15; i++)
{
NF.AddSample(MathF.Sin((i * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 4) * NF.BinsPerOctave);
}
// 16th sample, top 5 octaves should be calculated.
NF.AddSample(MathF.Sin((15 * Omega) + PHASE_OFFSET), true);
CheckAllBins((NF.OctaveCount - 5) * NF.BinsPerOctave);
void CheckAllBins(int contentStart)
{
for (ushort i = 0; i < contentStart; i++) // This octave should not yet have been calculated.
{
Assert.IsTrue(NF.Magnitudes[i] == 0, "Bin " + i + " should have been empty");
}
for (ushort i = (ushort)contentStart; i < NF.BinCount; i++) // All other bins should have at least a slight amount of content.
{
Assert.IsTrue(NF.Magnitudes[i] != 0, "Bin " + i + " should not have been empty");
}
}
}
public void OutputBinTestCompondSineProprotional(float testFreq1, float testFreq2, int expectedPeak1, int expectedPeak2, float ratio)
{
const float BASE_FREQ = 55F; // A2
ShinNoteFinderDFT NF = new ShinNoteFinderDFT();
NF.CalculateFrequencies(BASE_FREQ);
NF.FillReferenceTables();
NF.PrepareSampleStorage();
// Fill input.
float Omega1 = testFreq1 * MathF.PI * 2 / NF.SampleRate;
float Omega2 = testFreq2 * MathF.PI * 2 / NF.SampleRate;
float[] TestWaveform = new float[NF.WindowSize / 2];
for (uint i = 0; i < TestWaveform.Length; i++)
{
float Wave1 = ratio * MathF.Sin(i * Omega1);
float Wave2 = (1 - ratio) * MathF.Sin(i * Omega2);
TestWaveform[i] = Wave1 + Wave2;
}
NF.AddSamples(TestWaveform);
// Get output
float[] Output = NF.Magnitudes;
// Find peaks
float PeakVal1 = -1F;
float PeakVal2 = -1F;
int PeakInd1 = -1;
int PeakInd2 = -1;
for (int i = 0; i < Output.Length; i++)
{
if (Output[i] > PeakVal1)
{
PeakVal2 = PeakVal1;
PeakVal1 = Output[i];
PeakInd2 = PeakInd1;
PeakInd1 = i;
}
else if (Output[i] > PeakVal2)
{
PeakVal2 = Output[i];
PeakInd2 = i;
}
}
// Sort the peaks
if (PeakInd1 > PeakInd2)
{
float ValTemp = PeakVal1;
PeakVal1 = PeakVal2;
PeakVal2 = ValTemp;
int IndTemp = PeakInd1;
PeakInd1 = PeakInd2;
PeakInd2 = IndTemp;
}
// Make sure peaks are correct and large enough
Assert.IsTrue(PeakVal1 > (1500F * ratio), "Peak 1 was not large enough");
Assert.IsTrue(PeakVal2 > (1500F * (1 - ratio)), "Peak 2 was not large enough");
Assert.IsTrue(PeakInd1 == expectedPeak1, "Peak 1 was in the wrong place");
Assert.IsTrue(PeakInd2 == expectedPeak2, "Peak 2 was in the wrong place");
// Make sure the ratio is about right
float Total = PeakVal1 + PeakVal2;
Assert.IsTrue(Math.Abs((PeakVal1 / Total) - ratio) < 0.05F, "Peak 1 was not balanced to ratio");
Assert.IsTrue(Math.Abs((PeakVal2 / Total) - (1 - ratio)) < 0.05F, "Peak 2 was not balanced to ratio");
// Make sure all far-away bins are small enough
for (int i = 0; i < Output.Length; i++)
{
if (Math.Abs(i - PeakInd1) > 3 &&
Math.Abs(i - PeakInd2) > 3)
{
Assert.IsTrue(Output[i] < (Math.Max(PeakVal1, PeakVal2) / 1.5F), "Too much noise far away from peaks");
}
}
}
