Sound: To MelSpectrogram...

A command that creates a MelSpectrogram object from every selected Sound object by band filtering in the frequency domain with a set of triangular filters.

The filter functions used are all triangular in shape on a mel frequency scale. Each filter function depends on three parameters, the lower frequency fl, the central frequency fc and the higher frequency fh. On a mel scale, the distances fc-fl and fh-fc are equal for each filter. The filter function is as follows:

H(f) = 0 for f ≤ fl and f ≥ fh

H(f) = (f - fl) / (fc - fl) for fl ≤ f ≤ fc

H(f) = (fh - f) / (fh - fc) for fc ≤ f ≤ fh

In general the number of filter values stored in each frame of the MelSpectrogram is an order of magnitude smaller than the number of sound samples in the corresponding analysis frame.

### Links to this page

- Sound: To MelFilter...
- Sound: To MFCC...