Optimal memory organization for scalable texture codecs in MPEG-4

This paper addresses the problem of minimizing memory size and memory acces ses in multiresolution texture coding architectures for discrete cosine tra nsform (DCT) and wavelet-based schemes used, for example, in virtual-world walkthroughs or facial animation scenes of an MPEG-4 system. The problem of minimizing the memory cost is important since memory accesses, memory band width limitations, and in general the correct handling of the data hows hav e become the true critical issues in designing high-speed and low-power vid eo-processing architectures and in efficiently using multimedia processors. For instance, the straightforward implementation of a multiresolution text ure codec typically needs an extra memory buffer of the same size as the im age to be encoded/decoded, We propose a new calculation schedule that reduc es this buffer memory size with up to two orders of magnitude, while still ensuring a number of external (off-chip) memory accesses that is very close to the theoretical minimum. The analysis is generic and is therefore usefu l for both wavelet and multiresolution DCT codecs.