Saturday, June 14, 10:30 AM - 12:00 PM
||Compression and Perceptual Coding for Computer-Based Environments|
||Karlheinz Brandenburg, Fraunhofer Institute for Integrated Circuits, Erlangen, Germany|
||Peter Noll, Technische Universitaet Berlin Institut fuer Natchrichentechnik und Theoretische Elektrotechtik, Berlin, Germany, Schuyler Quackenbush, AT&T Laboratories, Florham Park, New Jersey, USA|
Peter Noll: We have seen rapid progress in high-quality compression of speech and signals. Linear prediction, subband coding, transform coding, as well as various forms of vector quantization and entropy coding techniques have been used to design efficient coding algothrithms which can achieve substantially more compression than was thought possible only a few years ago. In the case of audio coding with its bandwidth of 20kHz and more, the concept of perceptual coding has paved the way for significant bit rate reductions.
Schuyler Quackenbush: The ISO/IEC MPEG-2 Advanced Audio Coding (AAC) technology delivers unsurpassed audio quality at rates at or below 64 kbps/channel. It has a very flexible bitstream syntax that supports multiple audio channels, sub woofer channels and embedded data channels. AAC combines the coding efficiencies of a high-resolution filter bank, backward-adaptive prediction, joint channel coding, and Huffman coding with a flexible coding architecture to permit application-specific functionalities while still delivering excellent signal compression. This paper describes the main components of the AAC system that permit it to achieve this level of audio compression and gives an overview of the set of features that the bitstream supports.
Karlheinz Brandenburg, Peter Noll
KARLHEINZ BRANDENBURG was born in Erlangen, Germany in 1954. He received M.S. (Diplom) degrees in Electrical Engineering in 1980 and in Mathematics in 1982 from Erlangen University. In 1989 he earned his Ph.D. in Electrical Engineering, also from Erlangen University, for work on digital audio coding and perceptual measurement techniques. From 1989 to 1990 he was with AT&T Bell Laboratories in Murray Hill, NJ, USA. He worked on the ASPEC perceptual coding technique and on the definition of the ISO/IEC MPEG/Audio Layer
3 system. In 1990 he returned to Erlangen University to continue the research on audio coding and to teach a course on digital audio technology. Since 1993 he is the head of the Audio/Multimedia department at the Fraunhofer Institute for Integrated Circuits (FhG-IIS). He has presented numerous papers at AES conventions. In 1994 he received the AES Fellowship Award for his work on
perceptual audio coding and pscychoacoustics. Dr. Brandenburg is a member of the technical committee on Audio and Electroacoustics of the IEEE Signal Processing Society and the AES. He has been an active member of the ISO MPEG standardization committee since the start in 1988. In MPEG Audio his main topics currently are the MPEG-2 Advanced Audio Coding standard (AAC) and MPEG-4 Audio, where he is the chair of the ad hoc group on MPEG-4 audio core experiments. working on advanced audio coding systems. Dr. Brandenburg
has been granted 12 patents and has several more pending.
PETER NOLL was a recipient of the 1976 NTG Award (Germany) and of the 1977 IEEE ASSP Senior Award (IEEE Acoustics, Speech, and Signal Processing Society, USA). 1982 he was elected to the Grade of an IEEE Fellow "for contributions to adaptive quantization and coding of speech signals". In 1994 he became Advisory Professor of the Beijing Institute of Technology, Beijing (China).
In 1996 be became a member of the Berlin-Brandenburgische Akademie der Wissenschaften (the former Prussian Academy of Science, founded in 1700 by Leibniz) and of the Akademie der Naturforscher Leopoldina (founded in 1652).
He is a member of the ISO/IEC Working Group 11 [Moving Pictures Experts Group (MPEG)] and has acted as chairman of its Subgroup on Audio from 1991 to 1995. The activity of this subgroup has led to standards for stereophonic (MPEG-1) and multichannel (MPEG-2) audio coding.