MFCC extraction of an audio file

MFCC 

How can we extract mfcc feature of an audio file (total 39 comprised of normal-delta-double delta) having window lenght of 25ms and window shift of 10ms?

Answer 1

[jibrahim]

Mudit,

Check out the mfcc function in Audio Toolbox.

https://www.mathworks.com/help/audio/ref/mfcc.html

[audioIn,fs] = audioread('Counting-16-44p1-mono-15secs.wav');

winLength = round(0.025 * fs);
overlapLength = round(0.015 * fs);

[coeffs,delta,deltadelta] = mfcc(audioIn,fs,'WindowLength',winLength,...
                                 'OverlapLength',overlapLength,...
                                 'NumCoeffs',13','LogEnergy','Ignore');

[Mary Jeethu A J]

Using this code I'd computed mfcc.And obtained 498*13 featured vector for cepstral coefficiets ,delta and delta -delta.13 is the number that represents the coefficients.Could you please let me know what 498 indicates?

I'd used an audio of 5 sec length. Is that number related to that? Or is it related to sometig like frames?

[MathWorks Audio Toolbox Team]

Hi Mary,

Yes, 498 is the number of windows (frames) over which you computed the mfcc. It depends on the duration of your signal, and the window parameters specified on the function (Window and OverlapLength). For the same window length, the longer your signal the larger this number.