Curved surface characterization in 3-D range images

A computational scheme is presented for obtaining a characteristic description of a free-form curved surface from 3-D range images whose natural modes are in the form of level (equidistance) contours. The novelty in this scheme is that dense surface contours are used to directly estimate the surface curvatures in a systematic fashion without having to explicitly or implicitly compute any partial derivatives. The principle of the scheme is described, and the framework of computational paradigm is outlined for a shape description (shape from level contours) of the free-form curved object from its local surface properties. The objective is to obtain an invariant viewpoint and stable representation that is useful in 3-D object reconstruction and recognition. Although the scheme is based on analysis of level contours, the computation model for shape representation is general and applicable to any dense range image