public void Test_SFF_Mel()
{
(double[] audio, int sampleRate) = AudioFile.ReadWAV("../../../../../data/cant-do-that-44100.wav");
int fftSize = 1 << 12;
var spec = new SpectrogramGenerator(sampleRate, fftSize, stepSize: 700);
var window = new FftSharp.Windows.Hanning();
spec.SetWindow(window.Create(fftSize / 3)); // sharper window than typical
spec.Add(audio);
Bitmap bmp = spec.GetBitmapMel(250);
bmp.Save("../../../../../dev/sff/halMel.png", System.Drawing.Imaging.ImageFormat.Png);
spec.SaveData("../../../../../dev/sff/halMel.sff", melBinCount: 250);
var spec2 = new SFF("../../../../../dev/sff/halMel.sff");
Assert.AreEqual(spec.SampleRate, spec2.SampleRate);
Assert.AreEqual(spec.StepSize, spec2.StepSize);
Assert.AreEqual(spec.Width, spec2.Width);
Assert.AreEqual(spec.FftSize, spec2.FftSize);
Assert.AreEqual(spec.NextColumnIndex, spec2.FftFirstIndex);
Assert.AreEqual(spec.Height, spec2.Height);
Assert.AreEqual(spec.OffsetHz, spec2.OffsetHz);
}
public void BuildSpectrogram(string _wavPath)
{
double[] audio; int sampleRate;
(audio, sampleRate) = ReadWAV(_wavPath);
var sg = new SpectrogramGenerator(sampleRate, fftSize: FFTSize, stepSize: FFTStepSize, maxFreq: MaxFrequency);
//sg.SetFixedWidth(SpectrogramWidth);
sg.Add(audio);
sg.SetColormap(ImageColormap);
//sg.SetFixedWidth(1024);
var bmp = sg.GetBitmapMel(melBinCount: 103, dB: true, dBScale: 10);
bmp.Save(ImagePath, System.Drawing.Imaging.ImageFormat.Jpeg);
//sg.SaveImage(ImagePath, dB: true, dBScale: 10);
}
public void Test_MelSpectrogram_MelScale()
{
(double[] audio, int sampleRate) = AudioFile.ReadWAV("../../../../../data/cant-do-that-44100.wav");
int fftSize = 4096;
var sg = new SpectrogramGenerator(sampleRate, fftSize, stepSize: 500);
sg.Add(audio);
Bitmap bmpMel = sg.GetBitmapMel(250);
bmpMel.Save("../../../../../dev/graphics/halMel-MelScale.png", ImageFormat.Png);
Bitmap bmpRaw = sg.GetBitmap();
Bitmap bmpCropped = new Bitmap(bmpRaw.Width, bmpMel.Height);
using (Graphics gfx = Graphics.FromImage(bmpCropped))
{
gfx.DrawImage(bmpRaw, 0, bmpMel.Height - bmpRaw.Height);
}
bmpCropped.Save("../../../../../dev/graphics/halMel-LinearCropped.png", ImageFormat.Png);
}
