Amendment 4 - Information technology - MPEG audio technologies - Part 1: MPEG Surround - Reference software for MPEG surround extension for 3D audio

This International Standard describes the MPEG Surround standard (Spatial Audio Coding, SAC), that is capable of re-creating N channels based on M < N transmitted channels, and additional control data. In the preferred modes of operating the spatial audio coding system, the M channels can either be a single mono channel or a stereo channel pair. The control data represents a significant lower data rate than required for transmitting all N channels, making the coding very efficient while at the same time ensuring compatibility with both M channel devices and N channel devices.

This International Standard incorporates a number of tools enabling a number of features that allow for broad application of the International Standard. A key feature is the ability to scale the spatial image quality gradually from very low spatial overhead towards transparency. Another key feature is that the compatible decoder input can be made compatible to existing matrix surround technologies. All tools are grouped to cover certain profiles