POTENTIALS, VALLEYS, AND DYNAMIC GLOBAL COVERINGS

We present a new approach to effect the transition between local and global representations. It is based on the notion of a covering, or a collection of objects whose union is equivalent to the full one. The mathematics of computing global coverings are developed in the context of curve detection, where an intermediate representation (the tangent field) provides a reliable local description of curve structure. This local information is put together globally in the form of a potential distribution. The elements of the covering are then short curves, each of which evolves in parallel to seek the valleys of the potential distribution. The initial curve positions are also derived from the tangent field, and their evolution is governed by variational principles. When stationary configurations are achieved, the global dynamic covering is defined by the union of the local dynamic curves.