MPEG-4 video decoder optimization

After a decade from its origin, MPEG, with its current MPEG-4 project, is now facing the challenge of providing a future-proof multimedia toolkit which aims at incorporating new and emerging technologies while ensuring backward compatibility with its previous and successful audio-visual standards. The paper provides an overview of the standard, focusing mainly on the video decoding aspects that, by their nature, represent one of the most peculiar features of the future specifications which are scheduled to become an international standard by the beginning of year 1999. The paper first briefly introduces the MPEG standards, focusing on the MPEG-4 Video part of the specification, giving an extensive presentation of a coding/decoding video process. The main part of the paper is focused on the optimization performed to realize a real time software video decoder based on the MMX^TM architecture compliant to the VM 8 MPEG-4 Video standard. A comparison with the reference video decoder is also presented