% mfcc - Mel-frequency ceptral coefficients
%
% mfcc ::
%    [[M]->[40]] ~'which of 40 available coeffs to return',
%    N:natural ~'analysis window size',
%    [[T]]     ~'input signal',
%    nonneg    ~'sampling rate'
% -> [[M,L]]   ~'MFCCs for L time slices'.
function y=mfcc(MX,N,x,fs)
	[pow,fx]=powspec(spdiag(hamming(N,'periodic'))*buffer(x,N,floor(N/2)),2^nextpow2(N+1));
	y=cepstrum(MX,melspace(400/3,min(7000,fs/2),42),fs*fx,pow);
end
