Scene Constraints-Aided Tracking of Human Body

This paper describes a new method for tracking of a human body in 3D motion by using constraints imposed on the body from the scene. An image-based approach for tracking exclusively uses a geometrical model of the human body. Since the model usually has a large number of degrees of freedom (DOF), a chance to be corrupted by noise increases during the tracking process, and the tracking may fall in an ill-posed problem. To cope with this problem, we pay our attention to that a human body can not move freely, and usually receive some constraints from the scene. The new method uses constraints imposed on position, velocity and acceleration of the part of the body from the scene. These constraints can reduce the DOF of the model. This reduction guarantees the tracking problem to be a wellposed problem, and prevents tracking errors by noise. Experiments with real image sequences support a precise tracking of the body.