V_LPCCC2AR Convert complex cepstrum to ar coefficients AR=(CC) MATLAB5 version
0001 function ar=v_lpccc2ar(cc) 0002 %V_LPCCC2AR Convert complex cepstrum to ar coefficients AR=(CC) 0003 % 0004 % MATLAB5 version 0005 0006 0007 % Copyright (C) Mike Brookes 1998 0008 % Version: $Id: v_lpccc2ar.m 10865 2018-09-21 17:22:45Z dmb $ 0009 % 0010 % VOICEBOX is a MATLAB toolbox for speech processing. 0011 % Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 0012 % 0013 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0014 % This program is free software; you can redistribute it and/or modify 0015 % it under the terms of the GNU General Public License as published by 0016 % the Free Software Foundation; either version 2 of the License, or 0017 % (at your option) any later version. 0018 % 0019 % This program is distributed in the hope that it will be useful, 0020 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0021 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0022 % GNU General Public License for more details. 0023 % 0024 % You can obtain a copy of the GNU General Public License from 0025 % http://www.gnu.org/copyleft/gpl.html or by writing to 0026 % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 0027 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0028 0029 [nf,p]=size(cc); 0030 rp=-(1:p); 0031 cc = cc .* rp(ones(nf,1),:); 0032 if p<2 0033 ar = [ones(nf,1) cc(:,1)]; 0034 else 0035 ar=zeros(nf,p+1); 0036 ar(:,1:3) = [ones(nf,1) cc(:,1) (cc(:,2)+cc(:,1).^2)/2]; 0037 for k=3:p 0038 ar(:,k+1) = (cc(:,k) + sum(cc(:,1:k-1).*ar(:,k:-1:2),2))/k; 0039 end 0040 end 0041