Operationally optimal vertex-based shape coding

A framework for the rate-distortion operationally optimal encoding of shape information in the intra mode is presented. It is shown that each curve approximation has a natural order. If the control-point encoding scheme is matched to this order and the distortion is carefully defined, then the optimal approximation can be found using a directed acyclic graph (DAG)-shortest-path algorithm. The minimum-maximum distortion optimization problem and the minimum total (average) distortion optimization problem can be both solved by similar means, using an appropriate definition of the DAG weight function.