lpcpf2cc.m

来自「MATLAB工具箱 内容挺丰富」· M 代码 · 共 38 行

function cc=lpcpf2cc(pf,np)
%LPCPF2CC Convert power spectrum to complex cepstrum CC=(PF,NP)
% Note this conversion is not exact unless the pf() spectrum is much > np

%      Copyright (C) Mike Brookes 1998
%
%      Last modified Tue May 12 16:20:30 1998
%
%   VOICEBOX home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
%
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%   This program is free software; you can redistribute it and/or modify
%   it under the terms of the GNU General Public License as published by
%   the Free Software Foundation; either version 2 of the License, or
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%   This program is distributed in the hope that it will be useful,
%   but WITHOUT ANY WARRANTY; without even the implied warranty of
%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%   GNU General Public License for more details.
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if nargin<2 np=size(pf,2)-2; end
cc=irfft(log(pf.')).';
cc(:,1)=[];
[nf,p]=size(cc);
if np>p
   cc=[cc zeros(nf,np-p)];
else
   cc(:,np+1:p)=[];
end