lpccc2pf.m

《matlab扩展编程》光盘资料.关于端点检测

function pf=lpccc2pf(cc,np,nc)
%LPCCC2PF Convert complex cepstrum to power spectrum PF=(CC,NP,NC)
% cc = complex cepstrum coefs
% np+2 = number of frequency values 0 to nyquist (default: np=size(cc,2))
% nc = number of cepstral coefs to use (default: nc=np);
% for high speed make np one less than a power of 2


%      Copyright (C) Mike Brookes 1998
%
%      Last modified Tue May 12 16:02:44 1998
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[nf,mc]=size(cc);
if nargin<2 np=mc+2; end
if nargin<3 nc=np; end
if nc==mc
   pf=exp(rsfft([zeros(nf,1) cc].',2*np+2).');
else
   pf=exp(rsfft([zeros(nf,1) lpccc2cc(cc,nc)].',2*np+2).');
end