aac - mpeg4 audio file extension(wireless terminal) 확장자

http://www.vialicensing.com/products/mpeg4aac/standard.html

MPEG-4 AAC has been specified as the high-quality general audio coder for 3G wireless terminals. Apple Computer has incorporated MPEG-4 AAC into QuickTime 6 and iTunes 4, as well as the latest version of its award-winning iPod portable music player. The Digital Radio Mondiale system (the next-generation digital replacement for radio broadcasting under 30 MHZ) builds on the audio coding of MPEG-4 AAC. These exciting platforms represent the state of the art in audio coding뾞nd Via Licensing is pleased to offer the MPEG-4 AAC Patent License Agreement.

The MPEG-4 AAC standard incorporates MPEG-2 AAC, forming the basis of the MPEG-4 audio compression technology for data rates above 32 kbps per channel. Additional tools increase the effectiveness of MPEG-2 AAC at lower bit rates, and add scalability or error resilience characteristics. These additional tools extend AAC into its MPEG-4 incarnation (ISO/IEC 14496-3, Subpart 4).

The MPEG-4 AAC patent license grants rights for multiple MPEG-4 AAC Object Types including, AAC LC (Low Complexity), AAC Scalable, and ER AAC LD (Low Delay).

A copy of the MPEG-4 Audio standard can be purchased from the ISO online store (search for "14496-3")