wehub-resource-sync
20 lines
560 B
Matlab
Executable File
20 lines
560 B
Matlab
Executable File
function [A, nodePot, edgePot] = im2mrf(im, J, sigma)
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% Convert a image to Ising MRF with distribution p(x)=exp(-sum(nodePot)-sum(edgePot)-lnZ)
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% Input:
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% im: row x col image
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% sigma: variance of Gaussian node potential
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% J: parameter of Ising edge
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% Output:
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% nodePot: 2 x n node potential
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% edgePot: 2 x 2 x m edge potential
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A = lattice(size(im));
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[s,t,e] = find(tril(A));
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nEdge = numel(e);
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e(:) = 1:nEdge;
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A = sparse([s;t],[t;s],[e;e]);
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z = [1;-1];
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y = reshape(im,1,[]);
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nodePot = (y-z).^2/(2*sigma^2);
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edgePot = repmat(-J*(z*z'),[1, 1, nEdge]); |