gusucode.com > 语音信号处理工具箱 - Voicebox源码程序 > Voicebox\cep2pow.m
function [m,c]=cep2pow(u,v,mode) %CEP2POW convert cepstral means and variances to the power domain % for now, we insist that u is a row vector % cepstral vector must include the 0'th coefficient % mode: 'c' pow=exp(irdct(cep)) [default] % 'f' pow=exp(rsfft(cep)/n) [fft length even] % 'fo' pow=exp(rsfft(cep)/n) [fft length odd] % Copyright (C) Mike Brookes 1998 % % Last modified Wed Jan 30 09:44:15 2002 % % VOICEBOX is a MATLAB toolbox for speech processing. Home page is at % 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. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% if nargin<3 mode='c'; end if min(size(v))==1 v=diag(v); end if any(mode=='f') n=2*length(u)-2; if any(mode=='o') n=n+1; end p=rsfft(u',n)/n; q=rsfft(rsfft(v,n)',n)/n^2; else p=irdct(u'); q=irdct(irdct(v)'); end m=exp(p+0.5*diag(q))'; c=(m'*m).*(exp(q)-1);