matlab - How to find normals to an edge in an image -


i doing work related eye images. did edge detection it. edge curve , not continuous. have assume continuous , find normals curve. how find normals using matlab?

you can see image below.

edge image

i want find normals upper curve. hope clear enough.

even though seems unintuitive, edge direction @ every pixel pretty estimate of normal. simplest solution, because doesn't involve curve fitting.

in matlab, can find pixel-wise edge directions using sobel filter:

[bw,thresh,gv,gh] = edge(i,'sobel'); edgedir = atan2(gv, gh);

this gives edge directions angles in radians.


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