2-D OBJECT RECOGNITION BY MULTISCALE TREE MATCHING

In this paper we present an efficient 2-D object recognition method th at uses multiscale tree representations. A planar object is represente d by means of a tree, in which each node corresponds to a boundary seg ment at some level of resolution and an are connects nodes correspondi ng to segments at successive levels that are spatially related. The pr oblem of matching an object against a model is formulated as the one o f determining the best mapping between nodes at all levels of the two associated trees. The proposed matching algorithm is based on dynamic programming and has optimal O(\T parallel to T'\) time complexity, whe re \T\ and \T'\ are the number of nodes in the two trees. (C) 1998 Pub lished by Elsevier Science Ltd on behalf of the Pattern Recognition So ciety. All rights reserved.