A quadratic motion-based object-oriented video codec

摘要

A novel motion-based object-oriented codec for video transmission at very low bit-rates is proposed. The object motion is modeled by quadratic transform with coefficients estimated via a nonlinear quasi-Newton method. The segmentation problem is put forward as a constrained optimization problem which interacts with the motion estimation process in the course of region growing. A context-based shape coding method which takes into account the image synthesis error as well as the geometric distortion, is also proposed. Quantitative and subjective performance results of the codec on various test sequences illustrate the superior performance of the method.