On the usefulness of object shape coding with MPEG-4

This paper reports the results of an in-depth analysis of the degree of usefulness of object shape coding in video compression. In particular, MPEG-4 is used as reference standard. The influence of different coding parameters on the performance is deeply examined and discussions on the results are provided. Object shape coding is compared with classical (MPEG-2) frame-based coding both at an objective level (by comparing PSNR/quality and bitrate/filesize) and at a subjective level (asking to a set of users to express their opinion on overall quality, cognitive effectiveness, and willingness to pay). In conclusion, this paper aims at answering to the question whether it is convenient to use object shape coding instead of frame-based coding or not.