An Overview of MPEG-4 Object-Based Encoding Algorithms

In this paper, we describe several object-based encoding issues and provide solutions based on the MPEG-4 coding standard. Specifically, we first consider the general problem of object-based rate control and the allocation of bits among each object. Going a step further, we then discuss the issues related to the allocation of bits between shape and texture and propose a method to model the rate-distortion characteristics of the shape. Finally, we describe some preliminary work that we have been doing towards optimizing the trade-off in spatial and temporal quality. For object-based coding, it is believed that significant coding gains can be achieved.