INTERNATIONAL ORGANISATION FOR STANDARDISATION
ORGANISATION INTERNATIONALE DE NORMALISATION
ISO/IEC JTC1/SC29/WG11
CODING OF MOVING PICTURES AND AUDIO

ISO/IEC JTC1/SC29/WG11 N2431
October 1998/Atlantic City

MPEG Audio 

Contents

Where is the MPEG Audio web site?

The URL of the MPEG Audio web site is:

http://www.tnt.uni-hannover.de/project/mpeg/audio/

Where can I find more information on the WEB?

There are some interesting sites where you can find more MPEG-Audio related informations:

• http://www.cselt.it/mpeg/
• http://www.licensing.philips.com/ordering/soft/documents343.html
• http://www.iis.fhg.de/audio/
• ftp://ftp.fhg.de/pub/layer3/

What is provided by MPEG-1, MPEG-2, and MPEG-4 Audio?

MPEG-1 (ISO/IEC 11172-3) provides

• single-channel ('mono') and two-channel ('stereo' or 'dual mono') coding at 32, 44.1, and 48 kHz sampling rate. The predefined bit rates range from 32 to 448 kbit/s for Layer I, from 32 to 384 kbit/s for Layer II, and from 32 to 320 kbit/s for Layer III.

MPEG-2 BC (ISO/IEC 13818-3) provides

• a backwards compatible multichannel extension to MPEG-1; up to 5 main channels plus a 'low frequent enhancement' (LFE) channel can be coded; the bit rate range is extended up to about 1 Mbit/s;
• an extension of MPEG-1 towards lower sampling rates 16, 22.05, and 24 kHz for bitrates from 32 to 256 kbit/s (Layer I) and from 8 to 160 kbit/s (Layer II & Layer III).

MPEG-2 AAC (ISO/IEC 13818-7) provides

• a very high-quality audio coding standard for 1 to 48 channels at sampling rates of 8 to 96 kHz, with multichannel, multilingual, and multiprogram capabilities. AAC works at bit rates from 8 kbit/s for a monophonic speech signal up to in excess of 160 kbit/s/channel for very-high-quality coding that permits multiple encode/decode cycles. Three profiles of AAC provide varying levels of complexity and scalability.

MPEG-4 (ISO/IEC 14496-3) will provide

• coding and composition of natural and synthetic audio objects at a very wide range of bit rates.