canny and adaptive threshold can go hand in hand. i.e you can threshold an image and then apply canny. Adaptive threshold turns the image into binary (either wh

canny and adaptive threshold can go hand in hand. i.e you can threshold an image and then apply canny. Adaptive threshold turns the image into binary (either white or black) and it works great when there are big shadows. e.g http://www.aforgenet.com/framework/docs/html/img/imaging/sample20.png http://www.aforgenet.com/framework/docs/html/img/imaging/sam... -> http://www.aforgenet.com/framework/docs/html/img/imaging/bradley_local_thresholding.png http://www.aforgenet.com/framework/docs/html/img/imaging/bra...