Editing ATRAC (section)

{{Short description|Audio codec by Sony}}
{{Use dmy dates|date=September 2024}}
{{Infobox file format
| icon = Atrac.svg{{!}}class=skin-invert
| icon_size = 200px
| extension = *.aa3, .aea, .at3, .at9, .atp, .hma<br />'''[[OpenMG]] container'''
* .oma, .omg
| owner = [[Sony|Sony Corporation]]
| genre = [[Audio file format|Audio]]
| container for =
| contained by =
| extended from =
| extended to =
| standard =
| open = No
| free  = No
}}
'''Adaptive Transform Acoustic Coding''' ('''ATRAC''') is a family of proprietary [[audio codec|audio compression algorithms]] developed by [[Sony]]. [[MiniDisc]] was the first commercial product to incorporate ATRAC, in 1992. ATRAC allowed a relatively small disc like MiniDisc to have the same running time as [[CD]] while storing audio information with minimal perceptible loss in quality. Improvements to the codec in the form of ATRAC3, ATRAC3plus, and ATRAC Advanced Lossless followed in 1999, 2002, and 2006 respectively.<ref>{{Cite web |url=http://www.siliconvalley.com/news/ci_6759779 |title=Siliconvalley.com
|access-date=2007-09-01 |archive-url=https://web.archive.org/web/20070902071937/http://www.siliconvalley.com/news/ci_6759779
|archive-date=2007-09-02
|url-status=dead }}</ref>

Files in ATRAC3 format originally had the {{code|.aa3}} extension; however, in most cases, the files would be stored in an [[OpenMG]] Audio container using the extension {{code|.oma}}. Previously, files that were encrypted with OpenMG had the {{code|.omg}} extension, which was replaced by {{code|.oma}} starting in [[SonicStage]] v2.1. Encryption is no longer compulsory as of v3.2.

Other MiniDisc manufacturers such as [[Sharp Corporation|Sharp]] and [[Panasonic]] also implemented their own versions of the ATRAC codec.