1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
|
function c=comp_nonsepdgt_multi(f,g,a,M,lt)
%-*- texinfo -*-
%@deftypefn {Function} comp_nonsepdgt_multi
%@verbatim
%COMP_NONSEPDGT_MULTI Compute Non-separable Discrete Gabor transform
% Usage: c=comp_nonsepdgt_multi(f,g,a,M,lt);
%
% This is a computational subroutine, do not call it directly.
%@end verbatim
%@strong{Url}: @url{http://ltfat.github.io/doc/comp/comp_nonsepdgt_multi.html}
%@end deftypefn
% Copyright (C) 2005-2016 Peter L. Soendergaard <peter@sonderport.dk>.
% This file is part of LTFAT version 2.3.1
%
% 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 3 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 should have received a copy of the GNU General Public License
% along with this program. If not, see <http://www.gnu.org/licenses/>.
% AUTHOR : Nicki Holighaus and Peter L. Soendergaard
% TESTING: TEST_NONSEPDGT
% REFERENCE: REF_NONSEPDGT
% Assert correct input.
L=size(f,1);
W=size(f,2);
N=L/a;
% ----- algorithm starts here, split into sub-lattices ---------------
c=zeros(M,N,W,assert_classname(f,g));
mwin=comp_nonsepwin2multi(g,a,M,lt,L);
% simple algorithm: split into sublattices
for ii=0:lt(2)-1
c(:,ii+1:lt(2):end,:)=comp_dgt(f,mwin(:,ii+1),lt(2)*a,M,[0 1],0,0,0);
end;
% Phase factor correction
E = zeros(1,N,assert_classname(f,g));
for win=0:lt(2)-1
for n=0:N/lt(2)-1
E(win+n*lt(2)+1) = exp(-2*pi*i*a*n*rem(win*lt(1),lt(2))/M);
end;
end;
c=bsxfun(@times,c,E);
|