/// <summary>
/// Only call this method for short recordings.
/// If accumulating data for long recordings then call the method for long recordings - i.e.
/// double[] spectralIndex = GenerateOscillationDataAndImages(FileInfo audioSegment, Dictionary configDict, false, false).
/// </summary>
public static FreqVsOscillationsResult GetFreqVsOscillationsDataAndImage(BaseSonogram sonogram, string algorithmName)
{
double sensitivity = DefaultSensitivityThreshold;
int sampleLength = DefaultSampleLength;
var freqOscilMatrix = GetFrequencyByOscillationsMatrix(sonogram.Data, sensitivity, sampleLength, algorithmName);
var image = GetFreqVsOscillationsImage(freqOscilMatrix, sonogram.FramesPerSecond, sonogram.FBinWidth, sampleLength, algorithmName);
var sourceName = Path.GetFileNameWithoutExtension(sonogram.Configuration.SourceFName);
// get the OSC spectral index
// var spectralIndex = ConvertMatrix2SpectralIndexBySummingFreqColumns(freqOscilMatrix, skipNRows: 1);
var spectralIndex = MatrixTools.GetMaximumColumnValues(freqOscilMatrix);
if (spectralIndex == null)
{
throw new ArgumentNullException(nameof(spectralIndex));
}
// DEBUGGING
// Add spectralIndex into the matrix because want to add it to image.
// This is for debugging only and can comment this line
int rowCount = freqOscilMatrix.GetLength(0);
MatrixTools.SetRow(freqOscilMatrix, rowCount - 2, spectralIndex);
var result = new FreqVsOscillationsResult
{
SourceFileName = sourceName,
FreqOscillationImage = image,
FreqOscillationData = freqOscilMatrix,
OscillationSpectralIndex = spectralIndex,
};
return(result);
}
/// <summary>
/// Creates an image from the frequency/oscillations matrix.
/// The y-axis scale = frequency bins as per normal spectrogram.
/// The x-axis scale is oscillations per second.
/// </summary>
/// <param name="freqOscilMatrix">the input frequency/oscillations matrix</param>
/// <param name="framesPerSecond">to give the time scale</param>
/// <param name="freqBinWidth">to give the frequency scale</param>
/// <param name="sampleLength">to allow calculation of the oscillations scale</param>
/// <param name="algorithmName">the algorithm used to compute the oscillations.</param>
/// <returns>bitmap image</returns>
public static Image GetFreqVsOscillationsImage(double[,] freqOscilMatrix, double framesPerSecond, double freqBinWidth, int sampleLength, string algorithmName)
{
// remove the high cycles/sec end of the matrix because nothing really happens here.
int maxRows = freqOscilMatrix.GetLength(0) / 2;
freqOscilMatrix = MatrixTools.Submatrix(freqOscilMatrix, 0, 0, maxRows - 1, freqOscilMatrix.GetLength(1) - 1);
// get the OSC spectral index
var spectralIndex = MatrixTools.GetMaximumColumnValues(freqOscilMatrix);
// Convert spectrum index to oscillations per second
double oscillationBinWidth = framesPerSecond / sampleLength;
//draw an image
freqOscilMatrix = MatrixTools.MatrixRotate90Anticlockwise(freqOscilMatrix);
// each value is to be drawn as a 5 pixel x 5 pixel square
int xscale = 5;
int yscale = 5;
if (maxRows < 10)
{
xscale = 10;
}
//var image1 = ImageTools.DrawMatrixInColour(freqOscilMatrix, xPixelsPerCell: xscale, yPixelsPerCell: yscale);
//var image2 = ImageTools.DrawVectorInColour(DataTools.reverseArray(spectralIndex), cellWidth: xscale);
var image1 = ImageTools.DrawMatrixInGrayScale(freqOscilMatrix, xPixelsPerCell: xscale, yPixelsPerCell: yscale, reverse: true);
spectralIndex = DataTools.NormaliseByScalingMaxValueToOne(spectralIndex);
var image2 = ImageTools.DrawVectorInGrayScaleWithoutNormalisation(DataTools.reverseArray(spectralIndex), xscale, yscale, reverse: true);
var image = ImageTools.CombineImagesInLine(new[] { image1, image2 });
// place a grid line every 5 cycles per second.
double cycleInterval = 5.0;
double xTicInterval = cycleInterval / oscillationBinWidth * xscale;
// a tic every 1000 Hz.
int herzInterval = 1000;
double yTicInterval = herzInterval / freqBinWidth * yscale;
int xOffset = xscale / 2;
int yOffset = yscale / 2;
image = ImageTools.DrawYaxisScale(image, 10, herzInterval, yTicInterval, yOffset);
image = ImageTools.DrawXaxisScale(image, 15, cycleInterval, xTicInterval, 10, -xOffset);
var titleBar = DrawTitleBarOfOscillationSpectrogram(algorithmName, image.Width);
var imageList = new List <Image> {
titleBar, image
};
var compositeBmp = (Bitmap)ImageTools.CombineImagesVertically(imageList);
return(compositeBmp);
}
public static double[] GetSpectralIndex_Osc(AudioRecording recordingSegment, int frameLength, int sampleLength, double sensitivity)
{
var spgm = GetSpectrogramMatrix(recordingSegment, frameLength);
// Sample length i.e. number of frames spanned to calculate oscillations per second
int framecount = spgm.GetLength(0);
// adjust sample length i.e. patch size for short recordings.
sampleLength = AdjustSampleSize(framecount, sampleLength);
var freqOscilMatrix = GetFrequencyByOscillationsMatrix(spgm, sensitivity, sampleLength, "autocorr-fft");
//NOTE: Generate an oscillations spectral index for making LDFC spectrograms by taking the max of each column
var spectralIndex = MatrixTools.GetMaximumColumnValues(freqOscilMatrix);
return(spectralIndex);
}
public static Image GetFreqVsOscillationsImage(double[,] freqOscilMatrix, double framesPerSecond, double freqBinWidth, int sampleLength, string algorithmName)
{
// remove the high cycles/sec end of the matrix because nothing really happens here.
freqOscilMatrix = MatrixTools.Submatrix(freqOscilMatrix, 0, 0, 30, freqOscilMatrix.GetLength(1) - 1);
// get the OSC spectral index
// double[] spectralIndex = ConvertMatrix2SpectralIndexBySummingFreqColumns(freqOscilMatrix, skipNrows: 0);
var spectralIndex = MatrixTools.GetMaximumColumnValues(freqOscilMatrix);
// Convert spectrum index to oscillations per second
double oscillationBinWidth = framesPerSecond / sampleLength;
//draw an image
freqOscilMatrix = MatrixTools.MatrixRotate90Anticlockwise(freqOscilMatrix);
int xscale = 5;
int yscale = 5;
var image1 = ImageTools.DrawMatrixInColour(freqOscilMatrix, xPixelsPerCell: xscale, yPixelsPerCell: yscale);
var image2 = ImageTools.DrawVectorInColour(DataTools.reverseArray(spectralIndex), cellWidth: xscale);
var image = ImageTools.CombineImagesInLine(new[] { image1, image2 });
// a tic every 5cpsec.
double cycleInterval = 5.0;
double xTicInterval = cycleInterval / oscillationBinWidth * xscale;
// a tic every 1000 Hz.
int herzInterval = 1000;
double yTicInterval = herzInterval / freqBinWidth * yscale;
int xOffset = xscale / 2;
int yOffset = yscale / 2;
image = ImageTools.DrawXandYaxes(image, 18, cycleInterval, xTicInterval, xOffset, herzInterval, yTicInterval, yOffset);
var titleBar = DrawTitleBarOfOscillationSpectrogram(algorithmName, image.Width);
var imageList = new List <Image> {
titleBar, image
};
var compositeBmp = (Bitmap)ImageTools.CombineImagesVertically(imageList);
return(compositeBmp);
}
