Advanced Audio Coding

Also found in: Medical, Acronyms, Wikipedia.

Advanced Audio Coding

(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.
This article is provided by FOLDOC - Free Online Dictionary of Computing (


(Advanced Audio Coding) An audio compression technology that is part of the MPEG-2 and MPEG-4 standards. AAC, especially MPEG-4 AAC, provides greater compression and better sound quality than MP3, which is also part of the MPEG standard.

Popularized by the iPod
AAC was chosen as the default format for Apple's iPod because of its sound quality and copy protection, which was administered through Apple's iTunes software. Songs purchased from the iTunes online store were sold with AAC copy protection, but Apple dropped the protection in 2009 (see FairPlay). iTunes allows users to rip their CDs to AAC as well as MP3.

AAC Profiles
AAC is available in profiles, which determine how the algorithms encode the audio data. The Main profile offers the highest quality. Low Complexity (LC) is lower quality, but uses less CPU processing, and Scalable Sampling Rate (SSR) is a variation of LC. Long Term Prediction was added in MPEG-4 to improve the Main profile. See aacPlus, Apple Lossless, MP3 and iPod. Following are the file extensions used for AAC:

 Extension   Type of File

     MP4   Standard MPEG-4 video & audio

     M4A   Lossy AAC and Lossless AAC

     M4P   Protected AAC
     M4B   Protected AAC audiobook
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
High-Efficiency Advanced Audio Coding (HE AAC) is an international standard for audio encoding authorized for use by Dolby Laboratories to hundreds of companies around the world.
When copy-restriction routines no longer lock songs to certain players or programs, a few other things will change.Apple's iPod -- which dominated the market before the arrival of the iTunes Store -- should still do well, as should the Advanced Audio Coding format Apple uses for iTunes downloads.
According to the company, the platform consists of semiconductor chips, as well as a set of multimedia software and protocol stack software, including multimedia features such as H.263 and H.264 video capability, as well as support for MPEG-1 Audio Layer 3 (MP3), Windows Media Audio (WMA), Advanced Audio Coding (AAC), aacPlus and Enhanced aacPlus audio formats.
of Southern California) present a senior undergraduate or graduate level textbook on advanced audio coding techniques.
- The AVIC-VH009MD, AVIC-VH009, and AVIC-ZH009 are equipped with a 5.1 multi-channel processor for playback of multi-channel programs such as DVD-Videos and the MPEG-2 AAC (MPEG-2 Advanced Audio Coding) sources from terrestrial TV broadcasts.

Full browser ?