Clb. Jordan et al., SHAPE REPRESENTATION AND CODING OF VISUAL OBJECTS IN MULTIMEDIA APPLICATIONS - AN OVERVIEW, Annales des telecommunications, 53(5-6), 1998, pp. 164-178
Emerging multimedia applications hale created the need for new functio
nalities in digital communications. Whereas existing compression stand
ards only deal with the audio-visual scene at a frame level, it is now
necessary to handle individual objects separately, thus allowing scal
able transmission as well as interactive scene recomposition by the re
ceiver. The future MPEG-4 standard aims at providing compression tools
addressing these functionalities. Unlike existing frame-based standar
ds, the corresponding coding schemes need to encode shape information
explicitly. This paper reviews existing solutions to the problem of sh
ape representation and coding. Region and contour coding techniques ar
e presented and their performance is discussed, considering coding eff
iciency and rare-distortion control capability: as well as flexibility
to application requirements such res progressive transmission, low-de
lay coding, and error robustness.