On Implicit Modelling for Fitting Purposes

Tracking and modeling people from video sequences has become an in­ creasingly important research topic, with applications inc1uding anima­ tion, surveillance and sports medicine. In this paper, we propose a model based 3-D approach to recovering both body shape and motion. It takes advantage of a sophisticated animation model to achieve both robustness and realism. Stereo sequences of people in motion serve as input to our system. From these, we extract a 2.5-D description of the scene and, optionally, silhouette edges. We propose an integrated frame­ work to fit the model and to track the person's motion. Constraints for 3-D points and silhouette edges are presented in detail. We recover not only the motion but also a fuH animation model c10sely resembling the subject.