OBJECT RECOGNITION USING SIGNATURES

Abstract

A method is described for quickly detecting the similarity between planar shapes. By normalizing the distance from boundary to its geometric center, a 2D shape can be represented as a 2pi periodic function which is invariant to both translation and scaling. In this function, the orientation of the original shape is converted to the translation only in one direction. In this way, it becomes easier to handle. The similarity measurement is the minimum value over the translation from 0 to 2pi. Experimental results are included for the comparison of a group of 24 shapes.