Local symmetry detection in natural images using a particle filtering approach

In this paper, we propose an algorithm to detect smooth local symmetries and contours of ribbon-like objects in natural images. The detection is formulated as a spatial tracking task using a particle filtering approach, extracting one part of a structure at a time. Using an adaptive local geometric model, the method can detect straight reflection symmetries in perfectly symmetrical objects as well as smooth local symmetries in curved elongated objects. In addition, the proposed approach jointly estimates spine and contours, making it possible to generate back ribbon objects. Experiments for local symmetry detection have been conducted on a recent extension of the Berkeley segmentation data sets. We also show that it is possible to retrieve specific geometrical objects using intuitive prior structural information.