MPEG - 4 : Audio / Video & Synthetic Graphics / Audio for Mixed Media

MPEG-4 addresses coding of digital hybrids of natural and synthetic, Aural and Visual (A/V) information. The objective of this Synthetic/Natural Hybrid Coding (SNHC) is to facilitate content-based manipulation, interoperability, and wider user access in the delivery of animated mixed media. SNHC will support non-real-time and passive media delivery, as well as more interactive, real-time applications. Integrated spatial-temporal coding is sought for audio, video, and 2D/3D computer graphics as standardized A/V objects. Targets of standardization include mesh-segmented video coding, compression of geometry, synchronization between A/V objects, multiplexing of streamed A/V objects, and spatialtemporal integration of mixed media types. Composition, interactivity, and scripting of A/V objects can thus be supported in client terminals, as well as in content production for servers, also more effectively enabling terminals as servers. Such A/V objects can exhibit high efficiency in transmission and storage, plus content-based interactivity, spatial-temporal scalability, and combinations of transient dynamic data and persistent downloaded data. This approach can lower bandwidth of mixed media, offer tradeoffs in quality vs. update for specific terminals, and foster varied distribution methods for content that exploit spatial and temporal coherence over busses and networks. MPEG-4 responds to trends at home and _________________________ 1 Evans & Sutherland Computer Corp., 600 Komas Drive, P.O. Box 58700, Salt Lake City, Utah 84158, USA, E-mail: [email protected] 2 Computer Graphics Lab (EPFL-LIG), Swiss Federal Institute of Technology, 1015 Lausanne, Switzerland, Email: [email protected], Web: http://ligwww.epfl.ch/ 3 DIST Department of Telecommunications, Computer and System Sciences, University of Genoa, Via Opera Pia 13, 16145 Genova, Italy, E-mail: [email protected], Web: http://www.dist.unige.it/ 4 AT&T Research Laboratories, Room HO 4E518, 101 Crawfords Corner Road, Holmdel, NJ 07733-3030, USA, E-mail: [email protected] 5 MIRALab CUI, University of Geneva, 24 rue du Général-Dufour, CH1211 Geneva 4, Switzerland, E-mail: [email protected], Web: http://miralabwww.unige.ch/ 6 Bell Laboratories, Lucent Technologies, Room 2B-231, 600 Mountain Avenue, Murray Hill, New Jersey 07974, USA, E-mail: [email protected]