V_LPCBWEXP expand formant bandwidths of LPC filter ARX=(AR,BW) minimum bandwidth will be BW*fs where fs is the sampling frequency the radius of each pole will be multiplied by R=exp(-BW*pi) To set the maximum pole radius to R use BW=-log(R)/PI.
0001 function arx=v_lpcbwexp(ar,bw) 0002 %V_LPCBWEXP expand formant bandwidths of LPC filter ARX=(AR,BW) 0003 %minimum bandwidth will be BW*fs where fs is the sampling frequency 0004 %the radius of each pole will be multiplied by R=exp(-BW*pi) 0005 % To set the maximum pole radius to R use BW=-log(R)/PI. 0006 0007 0008 0009 % Copyright (C) Mike Brookes 1998 0010 % Version: $Id: v_lpcbwexp.m 10865 2018-09-21 17:22:45Z dmb $ 0011 % 0012 % VOICEBOX is a MATLAB toolbox for speech processing. 0013 % Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 0014 % 0015 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0016 % This program is free software; you can redistribute it and/or modify 0017 % it under the terms of the GNU General Public License as published by 0018 % the Free Software Foundation; either version 2 of the License, or 0019 % (at your option) any later version. 0020 % 0021 % This program is distributed in the hope that it will be useful, 0022 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0023 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0024 % GNU General Public License for more details. 0025 % 0026 % You can obtain a copy of the GNU General Public License from 0027 % http://www.gnu.org/copyleft/gpl.html or by writing to 0028 % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 0029 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0030 0031 [nf,p1]=size(ar); 0032 k=exp(-pi*(0:p1-1)*bw); 0033 arx=ar.*k(ones(nf,1),:);