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Get Mel Scale working after many years
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Got mel scale working.
Now works for drawing spectrograms AND for FrequencyScale class.
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@towsey @atruskie
towsey authored and atruskie committed Jun 8, 2018
1 parent 5a600f0 commit 610c9b9
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Showing 3 changed files with 196 additions and 100 deletions.
5 changes: 3 additions & 2 deletions src/AnalysisPrograms/Sandpit.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -69,7 +69,7 @@ public override Task<int> Execute(CommandLineApplication app)
//ConcatenateTwelveImages();
//CubeHelixDrawTestImage();
//DrawLongDurationSpectrogram();
DrawClusterSequence();
//DrawClusterSequence();

//ExtractSpectralFeatures();
//HerveGlotinMethods();
Expand All @@ -85,7 +85,7 @@ public override Task<int> Execute(CommandLineApplication app)
//TEST_FilterMovingAverage();
//TestImageProcessing();
//TestMatrix3dClass();
//TestsOfFrequencyScales();
TestsOfFrequencyScales();
//TestReadingFileOfSummaryIndices();
//TestStructureTensor();
//TestWavelets();
Expand Down Expand Up @@ -1209,6 +1209,7 @@ public static void TestsOfFrequencyScales()
{
// FrequencyScale.TESTMETHOD_LinearFrequencyScaleDefault();
// FrequencyScale.TESTMETHOD_LinearFrequencyScale();
FrequencyScale.TESTMETHOD_MelFrequencyScale();
// FrequencyScale.TESTMETHOD_OctaveFrequencyScale1();
// FrequencyScale.TESTMETHOD_OctaveFrequencyScale2();

Expand Down
169 changes: 127 additions & 42 deletions src/AudioAnalysisTools/DSP/FrequencyScale.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@ namespace AudioAnalysisTools.DSP
using TowseyLibrary;
using WavTools;

// IMPORTANT NOTE: If you are converting Herz scale from LINEAR to OCTAVE, this conversion MUST be done BEFORE noise reduction
// IMPORTANT NOTE: If you are converting Herz scale from LINEAR to MEL or OCTAVE, this conversion MUST be done BEFORE noise reduction

/// <summary>
/// All the below octave scale options are designed for a final freq scale having 256 bins.
Expand All @@ -38,16 +38,43 @@ public class FrequencyScale
/// CONSTRUCTOR
/// Calling this constructor assumes a full-scale linear freq scale is required
/// </summary>
public FrequencyScale(int nyquist, int frameSize, int hertzLinearGridInterval)
public FrequencyScale(int nyquist, int frameSize, int hertzGridInterval)
{
this.ScaleType = FreqScaleType.Linear;
this.Nyquist = nyquist;
this.WindowSize = frameSize;
this.FinalBinCount = frameSize / 2;
this.HertzLinearGridInterval = hertzLinearGridInterval;
this.HertzGridInterval = hertzGridInterval;
this.LinearBound = nyquist;
this.BinBounds = this.GetLinearBinBounds();
this.GridLineLocations = GetLinearGridLineLocations(nyquist, this.HertzLinearGridInterval, this.FinalBinCount);
this.GridLineLocations = GetLinearGridLineLocations(nyquist, this.HertzGridInterval, this.FinalBinCount);
}

/// <summary>
/// Initializes a new instance of the <see cref="FrequencyScale"/> class.
/// CONSTRUCTOR
/// Calling this constructor assumes either Linear or Mel is required but not Octave
/// </summary>
public FrequencyScale(FreqScaleType type, int nyquist, int frameSize, int finalBinCount, int hertzGridInterval)
{
this.ScaleType = type;
this.Nyquist = nyquist;
this.WindowSize = frameSize;
this.FinalBinCount = finalBinCount;
this.HertzGridInterval = hertzGridInterval;
if (type == FreqScaleType.Mel)
{
this.BinBounds = this.GetMelBinBounds();
this.GridLineLocations = GetMelGridLineLocations(this.HertzGridInterval, nyquist, this.FinalBinCount);
this.LinearBound = 1000;
}
else
{
// linear is the default
this.BinBounds = this.GetLinearBinBounds();
this.GridLineLocations = GetLinearGridLineLocations(nyquist, this.HertzGridInterval, this.FinalBinCount);
this.LinearBound = nyquist;
}
}

/// <summary>
Expand All @@ -64,23 +91,20 @@ public FrequencyScale(FreqScaleType fst)
this.Nyquist = 11025;
this.WindowSize = 512;
this.FinalBinCount = 256;
this.HertzLinearGridInterval = 1000;
this.HertzGridInterval = 1000;
this.LinearBound = this.Nyquist;
this.BinBounds = this.GetLinearBinBounds();
this.GridLineLocations = GetLinearGridLineLocations(this.Nyquist, this.HertzLinearGridInterval, 256);
this.GridLineLocations = GetLinearGridLineLocations(this.Nyquist, this.HertzGridInterval, 256);
}
else if (fst == FreqScaleType.Mel)
{
// Do not have Mel scale working yet.
LoggedConsole.WriteErrorLine("WARNING: Mel Scale needs to be debugged.");
LoggedConsole.WriteErrorLine(" Assigning parameters for DEFAULT Linear FREQUENCY SCALE.");
LoggedConsole.WriteErrorLine(" Call other CONSTUCTOR to control linear scale.");
LoggedConsole.WriteErrorLine("WARNING: Assigning DEFAULT parameters for MEL FREQUENCY SCALE.");
this.Nyquist = 11025;
this.WindowSize = 512;
this.FinalBinCount = 256;
this.HertzLinearGridInterval = 1000;
this.FinalBinCount = 128;
this.HertzGridInterval = 1000;
this.LinearBound = this.Nyquist;
this.GridLineLocations = GetLinearGridLineLocations(this.Nyquist, this.HertzLinearGridInterval, 256);
this.GridLineLocations = GetMelGridLineLocations(this.HertzGridInterval, this.Nyquist, this.FinalBinCount);
}
else
{
Expand Down Expand Up @@ -115,9 +139,9 @@ public FrequencyScale(FreqScaleType fst)
public FreqScaleType ScaleType { get; set; }

/// <summary>
/// Gets or sets herz interval between gridlines when using a linear scale
/// Gets or sets herz interval between gridlines when using a linear or mel scale
/// </summary>
public int HertzLinearGridInterval { get; set; }
public int HertzGridInterval { get; set; }

/// <summary>
/// Gets or sets top end of the linear part of an Octave Scale spectrogram
Expand Down Expand Up @@ -204,6 +228,27 @@ public int GetBinIdInReducedSpectrogramForHerzValue(int herzValue)
return binBounds;
}

/// <summary>
/// Returns an [N, 2] matrix with bin ID in column 1 and lower Herz bound in column 2 but on Mel scale
/// </summary>
public int[,] GetMelBinBounds()
{
double maxMel = (int)MFCCStuff.Mel(this.Nyquist);
int melBinCount = this.FinalBinCount;
double melPerBin = maxMel / melBinCount;

var binBounds = new int[this.FinalBinCount, 2];

for (int i = 0; i < melBinCount; i++)
{
binBounds[i, 0] = i;
double mel = i * melPerBin;
binBounds[i, 1] = (int)MFCCStuff.InverseMel(mel);
}

return binBounds;
}

/// <summary>
/// T.
/// </summary>
Expand Down Expand Up @@ -260,42 +305,30 @@ public static int[] CreateLinearYaxis(int herzInterval, int nyquistFreq, int ima
/// <summary>
/// THIS METHOD NEEDS TO BE DEBUGGED. HAS NOT BEEN USED IN YEARS!
/// Use this method to generate grid lines for mel scale image
/// Currently this method is only called from FrequncyScale.Draw1kHzLines(Bitmap bmp, bool doMelScale, int nyquist, double freqBinWidth)
/// and when bool doMelScale = true;
/// Currently this method is only called from BaseSonogram.GetImage() when bool doMelScale = true;
/// Frequencyscale.Draw1kHzLines(Bitmap bmp, bool doMelScale, int nyquist, double freqBinWidth)
/// </summary>
public static int[,] CreateMelYaxis(int herzInterval, int nyquistFreq, int imageHt)
public static int[,] GetMelGridLineLocations(int gridIntervalInHertz, int nyquistFreq, int melBinCount)
{
int minFreq = 0;
int maxFreq = nyquistFreq;
double minMel = MFCCStuff.Mel(minFreq);
int melRange = (int)(MFCCStuff.Mel(maxFreq) - minMel + 1);
double pixelPerMel = imageHt / (double)melRange;

// assume mel scale grid lines will only go up to 10 kHz.
var vScale = new int[10, 2];
double maxMel = (int)MFCCStuff.Mel(nyquistFreq);
double melPerBin = maxMel / melBinCount;
int gridCount = nyquistFreq / gridIntervalInHertz;

//LoggedConsole.WriteLine("minMel=" + minMel.ToString("F1") + " melRange=" + melRange + " hertzLinearGridInterval=" + hertzLinearGridInterval + " imageHt=" + imageHt + " pixelPerMel=" + pixelPerMel);
var gridLines = new int[gridCount, 2];

for (int f = minFreq + 1; f < maxFreq; f++)
for (int f = 1; f <= gridCount; f++)
{
// convert freq value to pixel id
if (f % 1000 == 0)
int herz = f * 1000;
int melValue = (int)MFCCStuff.Mel(herz);
int melBinId = (int)(melValue / melPerBin);
if (melBinId < melBinCount)
{
//int hzOffset = f - this.minFreq;
int melOffset = (int)(MFCCStuff.Mel(f) - minMel);
int pixelId = (int)(melOffset * pixelPerMel) + 1;
if (pixelId >= imageHt)
{
pixelId = imageHt - 1;
}

//LoggedConsole.WriteLine("f=" + f + " melOffset=" + melOffset + " pixelID=" + pixelID);
vScale[0, 0] = pixelId;
vScale[0, 1] = f;
gridLines[f - 1, 0] = melBinId;
gridLines[f - 1, 1] = herz;
}
}

return vScale;
return gridLines;
}

public static void DrawFrequencyLinesOnImage(Bitmap bmp, int[,] gridLineLocations)
Expand Down Expand Up @@ -482,6 +515,58 @@ public static void TESTMETHOD_LinearFrequencyScale()
Console.WriteLine("\n\n");
}

/// <summary>
/// METHOD TO CHECK IF SPECIFIED MEL FREQ SCALE IS WORKING
/// Check it on standard one minute recording.
/// </summary>
public static void TESTMETHOD_MelFrequencyScale()
{
var recordingPath = @"C:\SensorNetworks\SoftwareTests\TestRecordings\BAC2_20071008-085040.wav";
var outputDir = @"C:\SensorNetworks\SoftwareTests\TestFrequencyScale".ToDirectoryInfo();
var expectedResultsDir = Path.Combine(outputDir.FullName, TestTools.ExpectedResultsDir).ToDirectoryInfo();
var outputImagePath = Path.Combine(outputDir.FullName, "melScaleSonogram.png");
var opFileStem = "BAC2_20071008";

var recording = new AudioRecording(recordingPath);

int nyquist = 11025;
int frameSize = 1024;
int finalBinCount = 256;
int hertzInterval = 1000;
FreqScaleType scaleType = FreqScaleType.Mel;
var freqScale = new FrequencyScale(scaleType, nyquist, frameSize, finalBinCount, hertzInterval);
var fst = freqScale.ScaleType;

var sonoConfig = new SonogramConfig
{
WindowSize = frameSize,
WindowOverlap = 0.2,
SourceFName = recording.BaseName,
DoMelScale = (scaleType == FreqScaleType.Mel) ? true : false,
MelBinCount = (scaleType == FreqScaleType.Mel) ? finalBinCount : frameSize / 2,

//NoiseReductionType = NoiseReductionType.Standard,
NoiseReductionType = NoiseReductionType.None,
NoiseReductionParameter = 0.0,
};

var sonogram = new SpectrogramStandard(sonoConfig, recording.WavReader);

// DO NOISE REDUCTION
var image = sonogram.GetImageFullyAnnotated(sonogram.GetImage(), "SPECTROGRAM: " + fst.ToString(), freqScale.GridLineLocations);
image.Save(outputImagePath, ImageFormat.Png);

// DO FILE EQUALITY TEST
string testName = "MelTest";
var expectedTestFile = new FileInfo(Path.Combine(expectedResultsDir.FullName, "MelFrequencyScaleTest.EXPECTED.json"));
var resultFile = new FileInfo(Path.Combine(outputDir.FullName, opFileStem + "MelFrequencyLinearScaleTestResults.json"));
Acoustics.Shared.Csv.Csv.WriteMatrixToCsv(resultFile, freqScale.GridLineLocations);
TestTools.FileEqualityTest(testName, resultFile, expectedTestFile);

LoggedConsole.WriteLine("Completed Mel Frequency Scale test");
Console.WriteLine("\n\n");
}

/// <summary>
/// METHOD TO CHECK IF Octave FREQ SCALE IS WORKING
/// Check it on standard one minute recording, SR=22050.
Expand Down
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