processpw.m

matlab book matlab book2

function processed = processpw;
% record input signal, detect endpoints and crop, calculate mel-frequency
% cepstrum co-efficients (functions melcepst.m and melbank.m taken from
% http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html, freeware copyright of
% Mel Brookes of Cambridge University.

fs = 10000; % set sampling rate
choppedok = 0; % initialise variable

% grab waveform and process it
while (choppedok == 0)
    recording; % notify user
    grabpw = wavrecord(fs*3,fs); % grab for 3 secs
    close(recording);
    if (length(grabpw) > 2000)
        chopped = endp(grabpw,fs); % chop the signal at the endpoints
        if (length(chopped) < 1000)
            tryagain; % display error box
        else
            choppedok = 1;
            processed = melcepst(chopped,fs); % calculate 12 co-efficients to represent signal
        end;
    end;
end;
return;