A modal framework for correspondence and description

The authors describe a framework for establishing correspondence, computing canonical descriptions, and recognizing objects that is based on the idea of describing objects by their generalized symmetries, as defined by the object's free vibration modes. A technique given by A. Pentland and S. Scarloff (1991) described objects in terms of the modes of some prototype shape. In contrast, this new method computes the object's modes directly from available image information. This results in greater generality and accuracy, and is applicable to data of any dimensionality. For the purposes of illustration, a detailed mathematical formulation of the method is given for 2-D problems, and it is demonstrated on gray-scale image and contour data.<>