Abstract
A method for classifying closed planar shapes is presented. A shape is preprocessed and represented by several ordered sequences of vertices which are obtained by using an optimal polygon approximation algorithm with different approximation error criteria. A dynamic alignment algorithm is used to compute a similarity index between two sets of shape descriptors. The shape recognition process is hierarchical and invariant to rotation, translation and scaling. Classification experiments using noisy contours and objects have been performed with satisfactory results.<>