gusucode.com > 语音信号处理工具箱 - Voicebox源码程序 > Voicebox\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 % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % 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 % (at your option) any later version. % % 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. % % You can obtain a copy of the GNU General Public License from % ftp://prep.ai.mit.edu/pub/gnu/COPYING-2.0 or by writing to % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% [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