Iterative edge detection

A computationally simple iterative edge detection procedure is described and illustrated. The edges give a rather pleasing representation of the original gray level picture. Repeated iteration produces increasingly thinner edges. One-pixel edge thickness is mostly achieved in approximately four iterations with a 5 × 5 local operator neighborhood. Preservation of the continuity of contours, however, is not emphasized. Excessive iteration using integer numbers fragments the edges before they vanish.