Editing Compact disc (section)

=== Audio CD ===
[[File:CDP101a.jpg|thumb|[[Sony CDP-101]] from 1982, the first commercially released [[CD]] player for [[consumer]]s]]
[[File:CD player.jpg|thumb|Philips CD100 from 1983, the first commercially released CD player in the US and Europe]]
{{Main|Compact Disc Digital Audio}}
The logical format of an audio CD (officially Compact Disc Digital Audio or CD-DA) is described in a document produced in 1980 by the format's joint creators, Sony and Philips.<ref>{{Cite web|title=IEC 60908:1999 {{!}} IEC Webstore|url=https://webstore.iec.ch/publication/3885|access-date=2020-07-09|website=webstore.iec.ch|archive-url=https://web.archive.org/web/20160506194944/https://webstore.iec.ch/publication/3885|archive-date=6 May 2016|url-status=live}}</ref> The document is known colloquially as the ''Red Book'' [[CD-DA]] after the color of its cover. The format is a two-channel 16-bit [[PCM]] encoding at a [[44.1 kHz|44.1&nbsp;kHz]] [[sampling rate]] per channel. [[Four-channel Compact Disc Digital Audio|Four-channel sound]] was to be an allowable option within the ''Red Book'' format, but has never been implemented. [[Monaural]] audio has no existing standard on a ''Red Book'' CD; thus, the mono source material is usually presented as two identical channels in a standard ''Red Book'' stereo track (i.e., [[mono sound#Mirrored mono|mirrored mono]]); an [[MP3 CD]], can have audio file formats with mono sound.

[[CD-Text]] is an extension of the ''Red Book'' specification for an audio CD that allows for the storage of additional text information (e.g., album name, song name, artist) on a standards-compliant audio CD. The information is stored either in the [[Optical disc authoring|lead-in area]] of the CD, where there are roughly five kilobytes of space available or in the [[subcode]] channels R to W on the disc, which can store about 31 megabytes.

[[Compact Disc + Graphics]] is a special audio compact disc that contains graphics data in addition to the audio data on the disc. The disc can be played on a regular audio CD player, but when played on a special CD+G player, it can output a graphics signal (typically, the CD+G player is hooked up to a television set or a computer monitor); these graphics are almost exclusively used to display lyrics on a television set for [[karaoke]] performers to sing along with. The CD+G format takes advantage of the channels R through W. These six bits store the graphics information.

[[CD + Extended Graphics]] (CD+EG, also known as CD+XG) is an improved variant of the [[#CD + Graphics|Compact Disc + Graphics]] (CD+G) format. Like CD+G, CD+EG uses basic CD-ROM features to display text and video information in addition to the music being played. This extra data is stored in subcode channels R-W. Very few CD+EG discs have been published.