In this paper, we present a method for robustly extracting the silhouette form of the participant within an interactive environment. The approach overcomes the inherent problems associated with traditional chroma-keying, background subtraction, and rear-light projection methods. We employ a specialized infrared system while not making the underlying technology apparent to those interacting within the environment. The design also enables multiple video projection screens to be placed around the user. As an example use of this technology, we present an interactive virtual aerobics system. Our current implementation is a portable system which can act as a re-usable infrastructure for many interactive projects.
James W. Davis, Aaron F. Bobick