www.pudn.com > voicebox2.zip > LPCLA2RF.M

function rf=lpcla2rf(la) 
%LPCLA2RF Convert log areas to reflection coefficients RF=(LA) 
 
 
%      Copyright (C) Mike Brookes 1997 
% 
%      Last modified Tue May 12 16:08:57 1998 
% 
%   VOICEBOX home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 
% 
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%   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 
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[nf,p2]=size(la); 
rf=-tanh((la(:,1:p2-1)-la(:,2:p2))/2);