Optical disc recording modes
Encyclopedia
In optical disc authoring
, there are multiple modes for recording, including Disc-At-Once, Track-At-Once, and Session-At-Once.
the disc contents in one pass, rather than a track
at a time as in Track At Once. DAO mode, unlike TAO mode, allows any amount of audio data (or no data at all) to be written in the "pre-gaps" between tracks.
One use of this technique, for example, is to burn track introductions to be played before each track starts. A CD player will generally display a negative time offset counting up to the next track when such pre-gap introductions play. Pre-gap
audio before the first track of the CD makes it possible to burn an unnumbered, "hidden" audio track. This track can only be accessed by "rewinding" from the start of the first track, backwards into the pre-gap
audio.
DAO recording is also the only way to write data to the unused R-W sub-channels. This allows for extended graphic and text features on an audio CD such as CD+G
and CD-Text
. It is also the only way to write audio files that link together seamlessly with no gaps, a technique often used in progressive rock
and other music genres.
is finished and two run-out blocks are written. One link block and four run-in blocks are written when the next track is recorded. TAO discs can have both data and audio at the same time.
There are 2 TAO writing modes
It uses a Disc At Once method with a fixed linear recording speed of 1.4 m/s, burning longer, sharper pits and lands. Since the pits and lands are longer, the quantity of information that can fit on a disc is less than with a normal method: 63 minutes instead of 74 minutes on a 650meg CD, and 68 minutes instead of 80 minutes on a 700meg CD.
The main advantage of this recording mode is an easier to read audio CD. According to a reviewer, the sound quality is noticeably better.
Optical disc authoring
Optical disc authoring, including DVD and Blu-ray Disc authoring , is the process of assembling source material—video, audio or other data—into the proper logical volume format to then be recorded onto an optical disc .-Process:To burn an optical disc, one usually first creates an...
, there are multiple modes for recording, including Disc-At-Once, Track-At-Once, and Session-At-Once.
CD Disc-At-Once
Disc-At-Once or DAO for CD-R media is a mode that mastersMaster recording
A multitrack recording master tape, disk or computer files on which productions are developed for later mixing, is known as the multi-track master, while the tape, disk or computer files holding a mix is called a mixed master.It is standard practice to make a copy of a master recording, known as...
the disc contents in one pass, rather than a track
Track (CD)
On an optical disc, a track or title is a subdivision of its content. Specifically, it is a consecutive set of sectors on the disc containing a block of data. One session may contain one or more tracks of the same or different types...
at a time as in Track At Once. DAO mode, unlike TAO mode, allows any amount of audio data (or no data at all) to be written in the "pre-gaps" between tracks.
One use of this technique, for example, is to burn track introductions to be played before each track starts. A CD player will generally display a negative time offset counting up to the next track when such pre-gap introductions play. Pre-gap
Pregap
The pregap on a Red Book audio CD is the portion of the audio track that precedes "index 01" for a given track in the table of contents . The pregap is typically two seconds long and usually, but not always, contains silence...
audio before the first track of the CD makes it possible to burn an unnumbered, "hidden" audio track. This track can only be accessed by "rewinding" from the start of the first track, backwards into the pre-gap
Pregap
The pregap on a Red Book audio CD is the portion of the audio track that precedes "index 01" for a given track in the table of contents . The pregap is typically two seconds long and usually, but not always, contains silence...
audio.
DAO recording is also the only way to write data to the unused R-W sub-channels. This allows for extended graphic and text features on an audio CD such as CD+G
CD+G
CD+G is an extension of the compact disc standard that can present low-resolution graphics alongside the audio data on the disc when played on a compatible device...
and CD-Text
CD-Text
CD-Text is an extension of the Red Book Compact Disc specifications standard for audio CDs. It allows for storage of additional information on a standards-compliant audio CD...
. It is also the only way to write audio files that link together seamlessly with no gaps, a technique often used in progressive rock
Progressive rock
Progressive rock is a subgenre of rock music that developed in the late 1960s and early 1970s as part of a "mostly British attempt to elevate rock music to new levels of artistic credibility." John Covach, in Contemporary Music Review, says that many thought it would not just "succeed the pop of...
and other music genres.
CD Track-At-Once
Track-At-Once or TAO is a recording mode where the recording laser stops after each trackTrack (CD)
On an optical disc, a track or title is a subdivision of its content. Specifically, it is a consecutive set of sectors on the disc containing a block of data. One session may contain one or more tracks of the same or different types...
is finished and two run-out blocks are written. One link block and four run-in blocks are written when the next track is recorded. TAO discs can have both data and audio at the same time.
There are 2 TAO writing modes
- Mode 1
- Mode 2 XA
DVD-R Disc At Once
Disc At Once recording for DVD-R media is a mode in which all data is written sequentially to the disc in one uninterrupted recording session. The on-disk contents result in a lead-in area, followed by the data, and closed by a lead-out area. The data is addressable in sectors of 2048 bytes each, with the first sector address being zero. There are no run-out blocks as in CD-R disc-at-once.Session At Once
Session at Once or SAO recording allows multiple sessions to be recorded and finalized on a single disc. The resulting disc can be read by computer drives, but sessions after the first are generally not readable by CD Audio equipment.Audio Master Quality Recording
Yamaha's Audio Master Quality Recording is intended for maximum compatibility audio CDs, but is only available on some models, notably the CRW3200 series and the F1 series.It uses a Disc At Once method with a fixed linear recording speed of 1.4 m/s, burning longer, sharper pits and lands. Since the pits and lands are longer, the quantity of information that can fit on a disc is less than with a normal method: 63 minutes instead of 74 minutes on a 650meg CD, and 68 minutes instead of 80 minutes on a 700meg CD.
The main advantage of this recording mode is an easier to read audio CD. According to a reviewer, the sound quality is noticeably better.