LPCSS2ZZ Convert s-place poles to z-plane poles ZZ=(SS) the s-plane is in units of Normalized Hz and so the imaginary part of each ss() value is in the range +-0.5 If you multiply ss by the sample frequency, a formant with frequency f and bandwidth b will give an s-plane pole-pair of approximately -b/2 +- j f
0001 function zz=lpcss2zz(ss) 0002 %LPCSS2ZZ Convert s-place poles to z-plane poles ZZ=(SS) 0003 %the s-plane is in units of Normalized Hz and so the imaginary part 0004 % of each ss() value is in the range +-0.5 0005 % 0006 % If you multiply ss by the sample frequency, a formant with 0007 % frequency f and bandwidth b will give an s-plane pole-pair 0008 % of approximately -b/2 +- j f 0009 0010 0011 % Copyright (C) Mike Brookes 1997 0012 % Version: $Id: lpcss2zz.m 713 2011-10-16 14:45:43Z dmb $ 0013 % 0014 % VOICEBOX is a MATLAB toolbox for speech processing. 0015 % Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 0016 % 0017 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0018 % This program is free software; you can redistribute it and/or modify 0019 % it under the terms of the GNU General Public License as published by 0020 % the Free Software Foundation; either version 2 of the License, or 0021 % (at your option) any later version. 0022 % 0023 % This program is distributed in the hope that it will be useful, 0024 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0025 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0026 % GNU General Public License for more details. 0027 % 0028 % You can obtain a copy of the GNU General Public License from 0029 % http://www.gnu.org/copyleft/gpl.html or by writing to 0030 % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 0031 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0032 0033 zz=exp(2*pi*ss);