Contour/surface registration using a physically deformable model

Abstract

Describes a new approach of surface/contour registration based on a physically deformable model. No prior knowledge about the types of geometric transformation is required for registration. Instead, the authors' approach views the surface as made of elastic material that will change shape in response to the applied external force. The registration of two surfaces/contours is the deformation process of one shape towards the other governed by physical laws. Before the deformation, the two shapes are roughly registered with a global affine transformation. The physically deformable model is then applied to deform one shape to match the other. The point correspondences between the two shapes are established when one shape is finally deformed to the other. In the 2D case, the model is similar to the active contour model but registration is formulated as an equilibrium problem instead of minimization problem. The result is a set of decoupled linear system equations that are easy to solve. It is also shown that, because of physical constraints imposed the authors' model is an improved version of Burr's (1981) dynamic contour model. Experimental results are presented to demonstrate the performance of the model.