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

ISO/IEC JTC1/SC29/WG11
MPEG98/N2116 (Audio)
March 1998/Tokyo

Source: Audio Subgroup
Title: Audio Press Release of the 43rd MPEG Meeting

Audio Press Release of the 43rd MPEG Meeting

Audio: Flexible audio decoding through use of standard ‘decoding complexity units’.

In defining the conformance points for the Audio Standard, two generic parameters have been introduced (Processor Reference Unit and Memory Reference Unit) that can characterize the resources needed by all MPEG-4 Audio tools. These parameters are intended to define performance levels. The advantage of these measures is that content authors can make full and flexible use of all the decoder resources – it allows for example a choice between one object (channel) with a sampling frequency of 48 kHz or two channels with 24 kHz. Trade-offs can ideally also be made between natural and Synthetic Audio, but the characterization of synthetic audio needs some further study, as rather complex operations can be required from the decoder using only very few transmitted bits.

The Audio FCD draft covers the range of audio applications, from low bitrate - down to 2 kb/s/ch - for communications applications, through medium bitrate - in the order of 16 to 24 kb/s/ch - for Internet radio and related applications, up to full broadcast quality applications at 64 kb/s/ch. MPEG-4 Audio supports natural speech and audio, synthetic or structured audio (e.g. music synthesis) and provides a communications or transport interface for Text to Speech (TTSI) applications.

Also, a web page specific to MPEG Audio matters has been established. In the four weeks since it was made public it is already proving to be very popular. The URL of the MPEG Audio Web Page is:
http://www.tnt.uni-hannover.de/project/mpeg/audio/

For more information, check the full Press Release of the 43rd MPEG Meeting.