Constraints on the Computation of Rigid Motion Parameters from Retinal Displacements.

Abstract : A mathematical formulation of the Rigid Motion Perception problem is described. The constraints on the parameters of rigid motion (i.e., three-dimensional velocities) obtained from image motion data (two-dimensional projected velocities) are analyzed. A brief survey of related work shows the lacunae in the existing body of research in this area. Uniqueness results and computational algorithms are presented to compute the rigid motion parameters from retinal velocities. The approximations involved in the velocity representation are stated. Algorithms and constraints to permit cooperative computation of motion and shape are described.