I=[2 3 10 4 6; 1 4 7 5 3; 5 2 8 4 3;8 2 1 7 3;1 9 8 3 4;];
D = padarray(I,[1 1],0,'both');
s = size(I);
N = padarray(reshape(1:numel(I),s),[1 1],0,'both');
pt = [1 1 1;1 0 1;1 1 1] > 0;
s1 = s+2;
out = zeros(s);
for ii=2:s1(1)-1
for jj=2:s1(2)-1
D1 = D(ii-1:ii+1,jj-1:jj+1);
K = N(ii-1:ii+1,jj-1:jj+1);
K = K(pt);
[~,i0] = max(D1(pt));
out(ii-1,jj-1) = K(i0);
end
end
or
I=[2 3 10 4 6; 1 4 7 5 3; 5 2 8 4 3;8 2 1 7 3;1 9 8 3 4;];
D = padarray(I,[1 1],0,'both');
s = size(I);
pt = [1 1 1;1 0 1;1 1 1] > 0;
a = -1:1;
j1 = [1;1;1]*a;
i1 = j1';
i1 = i1(pt);
j1 = j1(pt);
s1 = s+2;
R = zeros(s);
C = zeros(s);
for ii=2:s1(1)-1
for jj=2:s1(2)-1
D1 = D(ii-1:ii+1,jj-1:jj+1);
[~,i0] = max(D1(pt));
R(ii-1,jj-1) = ii + i1(i0) - 1;
C(ii-1,jj-1) = jj + j1(i0) - 1;
end
end
or
I=[2 3 10 4 6; 1 4 7 5 3; 5 2 8 4 3;8 2 1 7 3;1 9 8 3 4;];
Ip = padarray(I,[1 1],0,'both');
s = size(Ip);
s0 = s - 2;
idxi = padarray(reshape(1:numel(I),s0),[1 1],0,'both');
ptr = reshape(bsxfun(@plus,(0:2)',(0:2)*s(1)),1,[]);
p2 = bsxfun(@plus,(1:s0(1))',(0:s0(2)-1)*s(1));
idx = bsxfun(@plus,p2(:),ptr([1:4,6:end]));
[~,ii] = max(Ip(idx),[],2);
s1 = size(idx);
out = reshape(idxi(idx(sub2ind(s1,(1:s1(1))',ii))),s0);
[R,C] = ind2sub(size(out),out);
Best Answer