bwmorph examples

Read binary image and display it.

BW = imread('circles.png');
imshow(BW);

Remove interior pixels to leave an outline of the shapes

BW2 = bwmorph(BW,'remove');
imshow(BW2)

Get the image skeleton.

BW3 = bwmorph(BW,'skel',Inf);
imshow(BW3)