comparison toolboxes/AudioInpaintingToolbox/Utils/dictionaries/Gabor_Dictionary.m @ 138:56d719a5fd31 ivand_dev

Audio Inpaintin Toolbox

+function D = Gabor_Dictionary(param)
+% Windowed Gabor dictionary. In this implementation, the dictionary matrix
+% is the concatenation of a DCT (left part of the matrix) and of a DST
+% (right part).
+% Note that one can use this dictionary 
+%  - either by constraining the simulaneous selection of cosine and sine
+%  atoms with same frequency in order to implement Gabor atoms;
+%  - or, without any selection constraint, by considering that the
+%  dictionary is not a Gabor dictionary but the concatenation of a DCT and 
+%  of a DST.
+%
+% Usage:
+%   D = Gabor_Dictionary(param)
+%
+% Inputs [and default values]:
+%   - param.N: frame length [256]
+%   - param.redundancyFactor: redundancy factor to adjust the number of
+%   frequencies [1]. The number of atoms in the dictionary equals 
+%   param.N*param.redundancyFactor
+%   - param.wd: weigthing window function [@wSine]
+%
+% Output:
+%   - Dictionary: D (cosine atoms followed by sine atoms)
+%
+%
+% -------------------
+%
+% Audio Inpainting toolbox
+% Date: June 28, 2011
+% By Valentin Emiya, Amir Adler, Maria Jafari
+% This code is distributed under the terms of the GNU Public License version 3 (http://www.gnu.org/licenses/gpl.txt).
+
+% Check and load default parameters
+defaultParam.N = 256;
+defaultParam.redundancyFactor = 1;
+defaultParam.wd = @wSine;
+
+if nargin<1
+    param = defaultParam;
+else
+    names = fieldnames(defaultParam);
+    for k=1:length(names)
+        if ~isfield(param,names{k}) || isempty(param.(names{k}))
+            param.(names{k}) = defaultParam.(names{k});
+        end
+    end
+end
+K = param.N*param.redundancyFactor; % number of atoms
+wd = param.wd(param.N); % weigthing window
+u = 0:(param.N-1); % time
+k=0:K/2-1; % frequency
+D = diag(wd)*[cos(2*pi/K*(u.'+1/2)*(k+1/2)),sin(2*pi/K*(u.'+1/2)*(k+1/2))];
+
+% normalisation
+D = D*diag(1./sqrt(diag(D'*D)));
+
+return