Refining Shape Correspondence for Similar Objects Using Strain

Abstract

Several applications - for example, study of biological tissue movement and organ growth - require shape correspondence with a physical basis, especially for shapes or regions lacking distinctive features. For this purpose, we propose the adaptation of mechanical strain, a well-established physical measure for deformation, to the problem of constructing shape correspondence and measuring similarity between non-rigid shapes. In this paper, we demonstrate how to calculate strain for a 2D surface embedded in 3D. We then adjust the correspondence between two surfaces so that the strain varies smoothly across the deformed surface (by minimizing the change in strain). The final strain on the deformed surface can be used as a measure of shape similarity.