Canny Edge Operator

Gradients -> edges
1. smoothing derivatives to suppress noise and compute gradient.
2. threshold to find regions of “significant” gradient
3. thin to get localized edge pixels

The canny edge detector

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pkg load image;

frizzy = imread('frizzy.png');
froomer = imread('froomer.png');
imshow(frizzy);
imshow(froomer);

frizzy_gray = rgb2gray(frizzy);
froomer_gray = rgb2gray(froomer);

frizzy_edges = edge(frizzy_gray, 'canny');
froomer_edges = edge(froomer_gray, 'canny');
imshow(frizzy_edges);
imshow(froomer_edges);

imshow(frizzy_edges & froomer_edges);