lpccc2ar.m

这是一个关于matlab语音处理工具箱

function ar=lpccc2ar(cc)
%LPCCC2AR Convert complex cepstrum to ar coefficients AR=(CC)
%
% MATLAB5 version


%      Copyright (C) Mike Brookes 1998
%
%      Last modified Tue May 12 16:01:17 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
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%   This program is distributed in the hope that it will be useful,
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%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%   GNU General Public License for more details.
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[nf,p]=size(cc);
rp=-(1:p);
cc = cc .* rp(ones(nf,1),:);
if p<2
  ar = [ones(nf,1) cc(:,1)];
else
 ar=zeros(nf,p+1);
 ar(:,1:3) = [ones(nf,1) cc(:,1) (cc(:,2)+cc(:,1).^2)/2];
  for k=3:p
    ar(:,k+1) = (cc(:,k) + sum(cc(:,1:k-1).*ar(:,k:-1:2),2))/k;
  end
end