getK_filters.m

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% Created by Jonathan T Barron and Jitendra Malik, Electrical Engineering
% and Computer Science, University of California, Berkeley.
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f1 = [1, 2, 1;
      0, 0, 0;
    -1, -2, -1]/8;

f2 = [1, 0, -1;
      2, 0, -2;
      1, 0, -1]/8;


f12 = [1, 0, -1;
       0, 0,  0;
      -1, 0,  1]/4;


f11 =  [1,  2,  1;
       -2, -4, -2; 
        1,  2,  1]/4;

f22 =  [1, -2, 1;
        2, -4, 2; 
        1, -2, 1]/4;


f1m = reshape(f1(end:-1:1), [3,3]);
f2m = reshape(f2(end:-1:1), [3,3]);
f12m = reshape(f12(end:-1:1), [3,3]);
f11m = reshape(f11(end:-1:1), [3,3]);
f22m = reshape(f22(end:-1:1), [3,3]);