Standards development within the Information Technology sector is harmonized with international standards development. Through the CSA Technical Committee on Information Technology (TCIT), Canadians serve as the Canadian Advisory Committee (CAC) on ISO/IEC Joint Technical Committee 1 on Information Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO member body for Canada and sponsor of the Canadian National Committee of the IEC.
Also, as a member of the International Telecommunication Union (ITU), Canada participates in the International Telegraph and Telephone Consultative Committee (ITU-T).
This Standard supersedes CAN/CSA-ISO/IEC 13818-7:04 (adoption of ISO/IEC 13818-7:2003). At the time of publication, ISO/IEC 13818-7:2004 is available from ISO and IEC in English only. CSA will publish the French version when it becomes available from ISO and IEC.
This International Standard describes the MPEG-2 audio non-backwards compatible standard called MPEG-2 Advanced Audio Coding, AAC , a higher quality multichannel standard than achievable while requiring MPEG-1 backwards compatibility.
This MPEG-2 AAC audio standard allows for ITU-R indistinguishable quality according to  at data rates of 320 kbit/s for five full-bandwidth channel audio signals. The AAC decoding process makes use of a number of required tools and a number of optional tools. Table 1 lists the tools and their status as required or optional. Required tools are mandatory in any possible profile. Optional tools may not be required in some profiles.