/// <summary>
/// Computes the spectogram of an audio file.
/// </summary>
/// <param name="decoder">The <see cref="IDecoder"/> instance.</param>
/// <returns>Chroma image.</returns>
public static Image ComputeSpectrogram(IDecoder decoder)
{
int numBands = 72;
var image = new Image(numBands);
var image_builder = new ImageBuilder(image);
var chroma = new Spectrum(numBands, MIN_FREQ, MAX_FREQ, FRAME_SIZE, SAMPLE_RATE, image_builder);
var fft = new FFT(FRAME_SIZE, OVERLAP, chroma, new LomontFFTService());
var processor = new AudioProcessor(SAMPLE_RATE, fft);
processor.Reset(decoder.SampleRate, decoder.Channels);
decoder.Decode(processor, 120);
processor.Flush();
return image;
}
//static int MAX_FILTER_WIDTH = 20;
public static Image Compute(string file, IDecoder decoder)
{
int numBands = 72;
Image image = new Image(numBands);
ImageBuilder image_builder = new ImageBuilder(image);
Spectrum chroma = new Spectrum(numBands, MIN_FREQ, MAX_FREQ, FRAME_SIZE, SAMPLE_RATE, image_builder);
FFT fft = new FFT(FRAME_SIZE, OVERLAP, chroma);
AudioProcessor processor = new AudioProcessor(SAMPLE_RATE, fft);
processor.Reset(decoder.SampleRate, decoder.Channels);
decoder.Decode(processor, 120);
processor.Flush();
//ExportImage(image, name, 0.5);
return image;
}
