f(x)
d/dx*f(x)
Finite differences responding to noise
Increasing noise
Solution: smooth first
f, h, h*f, α/αx*(h*f)
where is the edge?
1 2 3 4 5 6 | for sigma = 1:3:10 h = fspecial('gaussian', fsize, sigma); out = imfilter(im, h); imshow(out); pause; end |