Finding contrasted and regular edges by a contrario detection of periodic subsequences

A new method to detect salient pieces of boundaries in an image is presented. After detecting perceptually meaningful level lines, periodic binary sequences are built by labeling each point in close curves as salient or non-salient. We propose a general and automatic method to detect meaningful subsequences within these binary sequences. Experimental results show its good performance, when tested with different saliency criteria, such as contrast, regularity, and the combination of both.