The Digital Fact Book - Quantel

MP3A high-performance, perceptual audio compression coding scheme which exploits theproperties of the human ear and brain while trying to maintain perceived sound quality.MPEG-1 and 2 define a family of three audio coding systems of increasing complexityand performance – Layer-1, Layer-2 and Layer-3. MP3 is shorthand for Layer-3 coding.MPEG defines the bitstream and the decoder but, to allow for future improvements,not an encoder. MP3 is claimed to achieve ‘CD quality’ at 128-112 kb/s – a compressionof between 10 and 12:1.See also: Auditory maskingWebsite: www.mp3-tech.orgMP@ML, MP@HLSee MPEG-2MPEG – generalMoving Picture Experts Group. This a working group of ISO/IEC for the developmentof international standards for compression, decompression, processing, and codedrepresentation of moving pictures, audio and their combination. It has also extended intometadata. Four MPEG standards were originally planned but the accommodation of HDTVwithin MPEG-2 has meant that MPEG-3 is now redundant. MPEG-4 is very broad andextends into multimedia applications. MPEG-7 is about metadata and MPEG-21 describesa ‘big picture’ multimedia framework.MWebsites: www.chiariglione.org/mpegwww.mpeg.orgwww.mpegif.orgMPEG-1A compression scheme designed to work at 1.2 Mb/s, the basic data rate of CD-ROMs,so that video could be played from CDs. Its quality is not sufficient for TV broadcast.125