function MEL = computeMelSpectrum (W,winShift,s)
% --------------------------------------------
% computeMelSpectrum (W,winShift,s)
% compute mel spectrum from time signal
%
% Returns mel spectral coefficients in
% matrix MEL.M(coefficientIndex,frameIndex).
% No energy normalization is performed.
% Signal energy 
% is copied from SPEC.e
% ('computeSpectrum') to vector MEL.e(frameIndex).
%
% parameters:
% W: matrix(channelIndex,FFTIndex) of mel filter coefficients 
% winShift: window shift [number of samples]
% s: vector of time samples
%
% last update 18.1.04
% --------------------------------------------

% compute local variables
[nofChannels,maxFFTIdx] = size(W);
fftLength = maxFFTIdx * 2;

% compute matrix X(fftIndex,timeFrameIndex) short term spectra
SPEC = computeSpectrum(fftLength,winShift,s);

% apply mel filter to spectra

MEL.M = W * SPEC.X;

%copy energy vector
MEL.e = SPEC.e ;