Advanced Audio Coding

Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. AAC is promoted as the successor to the MP3 format by MP3’s creator, Fraunhofer IIS.Depending on the encoder used, AAC generally achieves better sound quality than MP3 at the same bitrate, particularly below 192 kbit/s.AAC’s most famous usage is as the default audio format of Apple's iPhone, iPod, iTunes, and the format used for all iTunes Store audio (with extensions for proprietary Digital Rights Management (DRM) where used).
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<audio> (AAC) A successor to MP3, allowing lower bit rates and more stable quality.
See MPEG-2 AAC Low Profile and MPEG-4 AAC Main Profile.
(2001-12-02)