Shape Matching Based on Rectangularized Curvature Scale-Space Maps

The curvature scale-space (CSS) technique is a shape descriptor in the MPEG-7 standard. To match a shape under query, a common approach is to exploit a simplified CSS map, which is produced by representing each arch-shaped contour of the original CSS map by a vertical line segment with the same height. However, we consider this approach is oversimplified, since some very useful information presented in the original CSS map has been totally ignored. To solve the problem, a new CSS map approximation is proposed in this paper, which is a rectangularized bin circumscribing each arch-shaped contour of the CSS map so that both the height and width characteristics are simultaneously captured and preserved. For conducting shape matching, an efficient method is further proposed, which has a significantly more succinct structure than the existing CSS matching technique used in MPEG-7. Simulation results have shown that the proposed method can yield superior performance.