pow2cep.m

《matlab扩展编程》光盘资料.关于端点检测

function [u,v]=pow2cep(m,c)
%CEP2POW convert cepstral means and variances to the power domain
% for now, we insist that u is a row vector
% cepstral vector includes the 0'th coefficient

%      Copyright (C) Mike Brookes 1998
%
%      Last modified Thu Jun 15 09:53:23 2000
%
%   VOICEBOX is a MATLAB toolbox for speech processing. Home page is at
%   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
%   the Free Software Foundation; either version 2 of the License, or
%   (at your option) any later version.
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%   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.
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%   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.
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if min(size(c))==1
   c=diag(c);
end
q=log(1+c./(m'*m));
v=rdct(rdct(q)');
u=rdct(log(m)'-0.5*diag(q))';