www.pudn.com > voicebox2.zip > LPCCC2AR.M

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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%   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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%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
%   GNU General Public License for more details. 
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%   Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 
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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