Oriented Filters

gistfile1.matlab

% Create four filters
[hx, hy] = gradient(fspecial('gaussian',[5 5],sigma));
[hx1, hy1] = altOrientFilter1(hx, hy);
[hx2, hy2] = altOrientFilter2(hx, hy);
[hx3, hy3] = altOrientFilter3(hx, hy);

% Run gaussian filters on the image
gx = double(imfilter(img,hx,'replicate', 'conv'));
gy = double(imfilter(img,hy,'replicate', 'conv'));
gx1 = double(imfilter(img,hx1,'replicate', 'conv'));
gy1 = double(imfilter(img,hy1,'replicate', 'conv'));
gx2 = double(imfilter(img,hx2,'replicate', 'conv'));
gy2 = double(imfilter(img,hy2,'replicate', 'conv'));
gx3 = double(imfilter(img,hx3,'replicate', 'conv'));
gy3 = double(imfilter(img,hy3,'replicate', 'conv'));

% Merge all filters
squareGD = (gx .* gx) + (gy .* gy);
squareGD = squareGD + (gx1 .* gx1) + (gy1 .* gy1);
squareGD = squareGD + (gx2 .* gx2) + (gy2 .* gy2);
squareGD = squareGD + (gx3 .* gx3) + (gy3 .* gy3);

% Run non-maxima supression
[mag, ] = max(sqrt(squareGD), [], 3);