MPEG Video Compression

[VelMurugan]

MPEG Video Compression

MPEG is the famous four-letter word which stands for the "Moving Pictures Experts Groups. To the real word, MPEG is a generic means of compactly representing digital video and audio signals for consumer distributionThe essence of MPEG is its syntax: the little tokens that make up the bitstream. MPEG's semantics then tell you (if you happen to be a decoder, that is) how to inverse represent the compact tokens back into something resembling the original stream of samples.

These semantics are merely a collection of rules (which people like to called algorithms, but that would imply there is a mathematical coherency to a scheme cooked up by trial and error....). These rules are highly reactive to combinations of bitstream elements set in headers and so forth. MPEG is an institution unto itself as seen from within its own universe. When (unadvisedly) placed in the same room, its inhabitants a blood-letting debate can spontaneously erupt among, triggered by mere anxiety over the most subtle juxtaposition of words buried in the most obscure documents. Such stimulus comes readily from transparencies flashed on an overhead projector.

Yet at the same time, this gestalt will appear to remain totally indifferent to critical issues set before them for many months. It should therefore be no surprise that MPEG's dualistic chemistry reflects the extreme contrasts of its two founding fathers: the fiery Leonardo Chairiglione (CSELT, Italy) and the peaceful Hiroshi Yasuda (JVC, Japan). The excellent byproduct of the successful MPEG Processes became an International Standards document safely administered to the public in three parts: Systems (Part), Video (Part 2), and Audio (Part 3).