Optical disc authoring
Encyclopedia
Optical disc authoring, including DVD
and Blu-ray Disc authoring (often referred to colloquially as burning), is the process of assembling source material—video, audio or other data—into the proper logical volume format to then be recorded ("burned") onto an optical disc
(typically a compact disc
or DVD
).
designed for the optical disc, and then burns the image to the disc. The disc image is a single file, built and stored on the hard drive, which contains the entire information to be contained on the disc.
Many optical disc authoring software create the disc image and burn in one bundled operation, so that end-users often do not know the distinction. However, a useful motivation for learning this distinction is that creating the disc image is an "expensive" (time-consuming) process. Most disc writing applications will silently delete this image from the "Temporary folder
" in which it was built unless users instruct the disc burning application to preserve the image, which can then be used for creating further copies of the same image without the need to rebuild the image each time.
There are also packet-writing applications that do not require writing the entire disc at once, but allow writing parts at a time, allowing the disc to be used in the same way as rewritable media such as a floppy disk
.
There exist many optical disc authoring technologies for optimizing the authoring process and preventing errors. Discs writable only once whose burn failed are colloquially termed coasters.
Some programs are able to mount a disc image as a file system
type, so these images appear as actual mounted discs. This feature can be useful for testing a disc image after authoring but before writing to the disc media.
audio compact disc is laid out in sessions. Each session consists of a lead-in, containing the session's Table of Contents; the program area in which the individual tracks are located; and the lead-out.
The number of tracks is limited to 99 on a disc. The specifications require at least one track in each session. The tracks are located in the program area of the session.
In multisession discs, the lead-in areas contain addresses of the previous sessions. The TOC written in the lead-in of the latest session is used to access the tracks.
on hard drives.
Nonstandard or corrupted TOC records are abused as a form of CD/DVD copy protection
, in e.g. the key2Audio
scheme.
The first lead-out is 6750 sectors (about 13 megabytes) long; each subsequent lead-out is 2250 sectors (4 megabytes) long.
s. There are, however, stand-alone devices like personal video recorders which can also author and record discs.
Creating an optical disc usually involves first creating an optical disc image with a full file system
designed for the optical disc, and then actually burning the image to the disc. Many programs create the disk image and burn in one bundled application (Quick Copy or Copy On-the-fly), such that end-users do not even know the distinction.
Disk file systems include ISO 9660
(often known simply as “ISO”) and Universal Disk Format
(UDF). ISO is most common for CDs and UDF is most common for DVDs.
There are also packet writing
applications that do not require writing the entire disc at once, but allow writing parts at a time, allowing the disc to be used as a random access removable medium (somewhat like a very large floppy, though with unique constraints).
(often known simply as "ISO") and Universal Disk Format
(UDF). ISO is most common for CDs and UDF is most common for DVDs.
, Rock Ridge
, Amiga Extensions to Rock Ridge, El Torito
, or the Apple ISO 9660 Extensions.
The Joliet file system was made by Microsoft. It makes it possible to have long file names
, among other things. Rock Ridge is a system providing ownership, fewer restrictions on the file names, and more. Amiga extensions allow use of Amiga attribute bits and comments. El Torito makes it possible to boot from a CD. The Apple Extensions enables creator codes, file type, and so on.
, making it possible to use the disc like a floppy disk
. This allows one to easily delete, create, and modify files, without having to write the whole disc again.
allows visual material on the disc to be recognised, interpreted and supported by electronic play devices.
DVD authoring
DVD authoring is the process of creating a DVD video capable of playing on a DVD player. DVD authoring software must conform to the specifications set by the DVD Forum group in 1995...
and Blu-ray Disc authoring (often referred to colloquially as burning), is the process of assembling source material—video, audio or other data—into the proper logical volume format to then be recorded ("burned") onto an optical disc
Optical disc
In computing and optical disc recording technologies, an optical disc is a flat, usually circular disc which encodes binary data in the form of pits and lands on a special material on one of its flat surfaces...
(typically a compact disc
Compact Disc
The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...
or DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
).
Process
To burn an optical disc, one usually first creates an optical disc image with a full file systemFile system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
designed for the optical disc, and then burns the image to the disc. The disc image is a single file, built and stored on the hard drive, which contains the entire information to be contained on the disc.
Many optical disc authoring software create the disc image and burn in one bundled operation, so that end-users often do not know the distinction. However, a useful motivation for learning this distinction is that creating the disc image is an "expensive" (time-consuming) process. Most disc writing applications will silently delete this image from the "Temporary folder
Temporary folder
In computing, a temporary folder or temporary directory is a directory used to hold temporary files. Many operating systems and some software automatically delete the contents of this directory at bootup or at regular intervals....
" in which it was built unless users instruct the disc burning application to preserve the image, which can then be used for creating further copies of the same image without the need to rebuild the image each time.
There are also packet-writing applications that do not require writing the entire disc at once, but allow writing parts at a time, allowing the disc to be used in the same way as rewritable media such as a floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
.
There exist many optical disc authoring technologies for optimizing the authoring process and preventing errors. Discs writable only once whose burn failed are colloquially termed coasters.
Some programs are able to mount a disc image as a file system
File system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
type, so these images appear as actual mounted discs. This feature can be useful for testing a disc image after authoring but before writing to the disc media.
Sessions
Data on a Red BookRed Book (audio CD standard)
Red Book is the standard for audio CDs . It is named after one of the Rainbow Books, a series of books that contain the technical specifications for all CD and CD-ROM formats.The first edition of the Red Book was released in 1980 by Philips and Sony; it was adopted by the Digital Audio Disc...
audio compact disc is laid out in sessions. Each session consists of a lead-in, containing the session's Table of Contents; the program area in which the individual tracks are located; and the lead-out.
The number of tracks is limited to 99 on a disc. The specifications require at least one track in each session. The tracks are located in the program area of the session.
In multisession discs, the lead-in areas contain addresses of the previous sessions. The TOC written in the lead-in of the latest session is used to access the tracks.
TOC
The Table of Contents (TOC) is the area where the layout of the tracks on the disc is described. It is located in the lead-in area of the disc session. The TOC on discs is in principle similar to partition tablePartition table
The term partition table is most commonly associated with partition table but it may be used generically to refer to other "formats" that divide a disk drive into partitions, such as: GUID Partition Table, Apple partition map, or BSD disklabel.An alternative term to generically refer to partition...
on hard drives.
Nonstandard or corrupted TOC records are abused as a form of CD/DVD copy protection
CD/DVD copy protection
CD/DVD copy protection is a blanket term for various methods of copy protection for CDs and DVDs. Such methods include DRM, CD-checks, Dummy Files, illegal tables of contents, over-sizing or over-burning the CD, physical errors, and bad sectors...
, in e.g. the key2Audio
Key2Audio
key2audio is a copy restriction system for Audio CDs, developed by Sony DADC. The system gained notoriety after it was discovered that one can effectively disable the system by tracing the outer edge of a CD with a felt-tip marker....
scheme.
Lead-In
The lead-in area of a CD session is the starting part of the session. It contains the TOC for the session, and the address of the next available free part of the disc available for the start of the next session, unless the disc is closed and therefore no more sessions can be added, or the disc is not multisession.Lead-Out
The lead-out area is the ending part of the CD session. When the session is closed, the lead-out area is written.The first lead-out is 6750 sectors (about 13 megabytes) long; each subsequent lead-out is 2250 sectors (4 megabytes) long.
Tracks
A track 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. There are Audio tracks and Data tracks.Hardware
Authoring is commonly done in software on computers with optical disc recorderOptical disc recorder
In computing, an optical disc drive is a disk drive that uses laser light or electromagnetic waves near the light spectrum as part of the process of reading or writing data to or from optical discs. Some drives can only read from discs, but recent drives are commonly both readers and recorders,...
s. There are, however, stand-alone devices like personal video recorders which can also author and record discs.
Software
Use of optical disc recorders require optical disc authoring software, sometimes called "burning applications" or "burner applications". Such software is usually sold with the recorder. Some operating systems come bundled with them.Creating an optical disc usually involves first creating an optical disc image with a full file system
File system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
designed for the optical disc, and then actually burning the image to the disc. Many programs create the disk image and burn in one bundled application (Quick Copy or Copy On-the-fly), such that end-users do not even know the distinction.
Disk file systems include ISO 9660
ISO 9660
ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
(often known simply as “ISO”) and Universal Disk Format
Universal Disk Format
Universal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and is an open vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660...
(UDF). ISO is most common for CDs and UDF is most common for DVDs.
There are also packet writing
Packet writing
Packet writing or IPW , is an optical disc recording technology used to allow write-once and rewritable CD and DVD media to be used in a similar manner to a floppy disk from within the operating system, i.e., it allows users to create, modify, and delete files and directories on demand without the...
applications that do not require writing the entire disc at once, but allow writing parts at a time, allowing the disc to be used as a random access removable medium (somewhat like a very large floppy, though with unique constraints).
File systems
Optical disk file systems include ISO 9660ISO 9660
ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
(often known simply as "ISO") and Universal Disk Format
Universal Disk Format
Universal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and is an open vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660...
(UDF). ISO is most common for CDs and UDF is most common for DVDs.
ISO 9660
ISO 9660 is a format mainly used on CDs. The ISO 9660 can be extended with JolietJoliet (file system)
Joliet is the name of an extension to the ISO 9660 file system. It has been specified and endorsed by Microsoft and has been supported by all versions of its Windows OS since Windows 95 and Windows NT...
, Rock Ridge
Rock Ridge
The Rock Ridge Interchange Protocol is an extension to the ISO 9660 volume format, commonly used on CDROM and DVD media, which adds POSIX file system semantics...
, Amiga Extensions to Rock Ridge, El Torito
El Torito (CD-ROM standard)
The El Torito Bootable CD Specification is an extension to the ISO 9660 CD-ROM specification. It is designed to allow a computer to boot from a CD-ROM...
, or the Apple ISO 9660 Extensions.
The Joliet file system was made by Microsoft. It makes it possible to have long file names
Long filename
Long filenames , are Microsoft's way of implementing filenames longer than the 8.3 filename, or short-filename, naming scheme used in Microsoft DOS in their modern FAT and NTFS filesystems. Because these filenames can be longer than an 8.3 filename, they can be more descriptive...
, among other things. Rock Ridge is a system providing ownership, fewer restrictions on the file names, and more. Amiga extensions allow use of Amiga attribute bits and comments. El Torito makes it possible to boot from a CD. The Apple Extensions enables creator codes, file type, and so on.
Universal Disk Format
Universal Disk Format (UDF) can be extended with Mount Rainier packet writingMount Rainier (packet writing)
Mount Rainier is a format for writable optical discs which provides the packet writing and defect management. Its goal is the replacement of the floppy disk...
, making it possible to use the disc like a floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
. This allows one to easily delete, create, and modify files, without having to write the whole disc again.
HighMAT
A compatibility technology called HighMATHighMAT
HighMAT is a media format jointly developed by Matsushita and Microsoft for personal CD authoring with music and photo content. Currently, burning photos and music content onto CD generally involves organizing the photos/music into directories...
allows visual material on the disc to be recognised, interpreted and supported by electronic play devices.