gusucode.com > 《MATLAB图像与视频处理实用案例详解》代码 > 《MATLAB图像与视频处理实用案例详解》代码/第 19 章 基于语音识别的信号灯图像模拟控制技术/voicebox/lpccc2pf.m
function pf=lpccc2pf(cc,np,nc) %LPCCC2PF Convert complex cepstrum to power spectrum PF=(CC,NP,NC) % cc = complex cepstrum coefs % np+2 = number of frequency values 0 to nyquist (default: np=size(cc,2)) % nc = number of cepstral coefs to use (default: nc=np); % for high speed make np one less than a power of 2 % Copyright (C) Mike Brookes 1998 % Version: $Id: lpccc2pf.m,v 1.4 2007/05/04 07:01:38 dmb Exp $ % % VOICEBOX is a MATLAB toolbox for speech processing. % 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 % http://www.gnu.org/copyleft/gpl.html or by writing to % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% [nf,mc]=size(cc); if nargin<2 np=mc+2; end if nargin<3 nc=np; end if nc==mc pf=exp(rsfft([zeros(nf,1) cc].',2*np+2).'); else pf=exp(rsfft([zeros(nf,1) lpccc2cc(cc,nc)].',2*np+2).'); end