Thomas Schmitt has made significant contributions to this glossary. See also http://www.dvdrhelp.com/glossary.

ASPI
     See Win32 ASPI

ATA

     Advanced Technology Attachment (ATA). The same thing as IDE.

ATAPI

     Advanced Technology Attachment (ATA) Packet Interface. The interface provides a mechanism for transferring and executing SCSI CDBs on IDE CD Drives and DVD Drives.

     IDE (also called ATA) was originally designed for hard drives only, but with help of ATAPI it is possible to connect other devices, in particular CD-ROMS to the IDE/EIDE connections.

     The ATAPI CD-ROM drives understand a subset of SCSI commands. In particular multi-initiator commands are neither needed nor defined for ATAPI devices.

BIN/CUE

     A CD-image format developed by Jeff Arnold for CDRWIN software on Microsoft Windows. Many other programs subsequently support using this format. The .CUE file is a text file which contains CD format and track layout information, while the .BIN file holds the actual data of each track.

Blu-ray Disc (BD)
     Optical media with capacity of 25 GB as single layer and 50 GB as double layer. See also "Media models and profiles".

CD
     Compact Disc. Capacity up to 900 MB. See also "Media models and profiles".

CD-DA
     Compact Disc Digital Audio, described in the ``Red Book'' or IEC 60908 (formerly IEC 908). This commonly referred to as an audio CD and what most people think of when you play a CD as it was the first to use the CD medium.

     See http://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)

CD+G

     Compact Disc + Graphics. An extension of the CD audio format contains a limited amount of graphics in subcode channels. This disc works in all audio players but the graphics portion is only available in a special CD+G or Karaoke player.

CD-i

     Compact Disc Interactive. An extension of the CD format designed around a set-top computer that connects to a TV to provide interactive home entertainment, including digital audio and video, video games, and software applications. Defined by the ``Green Book'' standard. http://www.icdia.org/. CD-i for video and video music has largely (if not totally) been superseded by VCDs.

CD-i Bridge

     A standard allowing CD-ROM XA discs to play on CD-i.  Kodak PhotoCDs are CD-XA Bridge discs.

CD-ROM

     Compact Disc Read Only Memory or ``Yellow Book'' describe in Standards ISO/IEC 10149. The data stored on it can be either in the form of audio, computer or video files.

CD-ROM Mode 1 and Mode2

     The Yellow Book specifies two types of tracks, Mode 1 and Mode 2. Mode 1 is used for computer data and text and has an extra error correction layer. Mode 2 is for audio and video data and has no extra correction layer. CD-ROM/XA An expansion of the CD-ROM Mode 2 format that allows both computer and audio/video to be mixed in the same track.

CD Text

     CD Text is a technology developed by Sony Corporation and Philips Electronics in 1996 that allows storing in an audio CD and its tracks information such as artist name, title, songwriter, composer, or arranger. Commercially available audio CDs sometimes contain CD Text information.

     Information on how CD Text is stored can be found in in older MMC standards.  Specifically, try ``Annex J'' of ``mmc3r10g.pdf''.

     An ``Unofficial CD Text FAQ'' is at http://web.ncf.ca/aa571/cdtext.htm

CD XA

     CD-ROM EXtended Architecture. A modification to the CD-ROM specification that defines two new types of sectors.  CD-ROM XA was developed jointly by Sony, Philips, and Microsoft, and announced in August 1988. Its specifications were published in an extension to the Yellow Book.  CD-i, Photo CD, Video CD and CD-EXTRA have all subsequently been based on CD-ROM XA.

     CD-XA defines another way of formatting sectors on a CD-ROM, including headers in the sectors that describe the type (audio, video, data) and some additional info (markers, resolution in case of a video or audio sector, file numbers, etc).

     The data written on a CD-XA is consistent with and can be in ISO-9660 file system format and therefore be readable by ISO-9660 file system translators. But also a CD-I player can read CD-XA discs even if its own `Green Book' file system only resembles ISO 9660 and isn't fully compatible.

DVD
     Digital Versatile Disc. Capacity up to 4.5 GB as single layer and 8.5 GB as double layer media. See also "Media models and profiles".

Defect management
     A method to compensate small amounts of bad spots on media by replacing them out of a pool of reserve blocks and performing address translation. The necessary checkreading slows down write performance by a factor of 2 or 3. Defect management applies by default to DVD-RAM and BD-RE. Optionally it can be formatted onto CD-RW and DVD+RW, where it has the name "Mount Rainier". Sequential BD-R can be formatted for defect management too.

Command Packet

     The data structure that is used to issue an ATAPI command. It contains a SCSI Command Descriptor Block (CDB).

ECMA-119 (ISO-9660)

     (http://www.ecma-international.org/publications/standards/Ecma-119.htm is a freely available specification which is technically identical to ISO 9660.

ECMA-167 (UDF)

     (http://www.ecma-international.org/publications/standards/Ecma-167.htm is a freely available specification which is also approved as ISO 13346. It serves as base for UDF.

ECMA-168

     (http://www.ecma-international.org/publications/standards/Ecma-168.htm is a freely available specification which is also approved as ISO 13490.

FSF

     Free Software Foundation, http://www.fsf.org/

GNU

     GNU is not UNIX, http://www.gnu.org/

IDE

     Integrated Drive Electronics. This is a commonly used interface for hard disk drives and CD-ROM drives. It is less expensive than SCSI, but offers slightly less in terms of performance.

ISO

     International Standards Organization.

ISO 13346

     ISO 13346 / ECMA-167 is a filesystem framework for data exchange on overwriteable or pseudo-overwriteable media. It serves as base of UDF.

ISO 13490

     ISO 13490 / ECMA-168 is an attempt to replace ISO 9660 by a format that allows finer write granularity and representation of typical disk file properties. It resembles ECMA-167 which led to UDF.

ISO 9660

     ISO 9660 / ECMA-119 is an operating-system independent filesystem format originally intended for CD-ROM media. It was standardized in 1988 and replaced the High Sierra standard for the logical format on CD-ROM media (ISO 9660 and High Sierra are identical in content, but the exact format is different). ISO 9660 and ECMA-119 are technically identical meanwhile.

     There are several specification levels. In Level 1, file names must be in the 8.3 format (no more than eight characters in the name, no more than three characters in the suffix) and in capital letters. Directory names can be no longer than eight characters. There can be no more than eight nested directory levels. Level 2 and 3 specifications allow file names up to 32 characters long. Level 3 allows data file sizes to be 4 GB or larger. File data content is stored in extents, i.e. contiguous sequences of blocks. A single extent can hold only up to 2 exp 32 - 1 bytes. So files of 4 GB or larger need more than one extent to be stored. Older operating systems might have trouble with multi-extent files.

Joliet extensions

     This ISO-9660 upward-compatible standard was developed for Windows 95 and Windows NT by Microsoft as an extension of ISO 9600 which allows the use of Unicode characters and supports file names up to 64 characters.

     See http://bmrc.berkeley.edu/people/chaffee/jolspec.html for the Joliet Specification.

     The name Joliet comes from the city in Illinois (U.S) that the standard was defined.

LBA

     Logical Block Addressing. Mapped integer numbers from CD Red Book Addressing MSF.  The starting sector is -150 and ending sector is 449849, which correlates directly to MSF: 00:00:00 to 99:59:74. Because an LBA is a single number it is often easier to work with in programming than an MSF.

Lead in

     The area of a CD where the Table Of Contents (TOC) and CD Text are stored.  I think it is supposed to be around 4500 (1 min) or more sectors in length.  On a CDR(W) the lead-in length is variable, because manufacturers have a different starting position indicated by the ATIP start of lead-in position that is recorded in the ATIP groove on the disk. For example:

     Ricoh Company Limited
          97:27:00, 97:27:06, 97:27:66

     Mitsubishi Chemical (Verbatim)
          97:34:21 to 97:34:25

LSN

     Logical Sector Number. Mapped integer numbers from CD Red Book Addressing MSF.  The starting sector is 0 and ending sector is 449699, which correlates to MSF: 00:00:00 to 99:59:74.  Because an LSN is a single number it is often easier to work with in programming than an MSF. Because it starts at 0 rather than -150 as is the case of an LBA it can be represented as an unsigned value.

MCN

     Media Catalog Number. A identification number on an audio CD.  Also called a UPC. Another identification number is ISRC.

MMC

     MMC (Multimedia Commands).

     MMC are raw commands for communicating with CDROM drives, CD-Rewriters, DVD-Rewriters, etc. The are subset of the larger SCSI command set. See also SCSI.

     Many manufacturers have adopted this standard and it also applies to ATAPI versions of their drives.

     The documents libcdio makes use of are described in the Multi-Media Commands standard (MMC). This document generally has a numeric level number appended. For example MMC-5 refers to ``Multi-Media Commands - 5.

Media models and profiles

     MMC classifies media as models, which describe their logical structure, and as profiles, which describe the capabilities of the drive with the particular media. So both are closely related but not identical.

     There are three model families: CD, DVD, Blu-ray. CD allows special sector formats like audio as well as data sectors of 2048 bytes. DVD and Blu-ray only record data sectors.

     Non-writable media: CD-ROM, DVD-ROM, BD-ROM.

     Write-once media: CD-R, DVD-R, DVD+R, BD-R.

     Reusable media: CD-RW, DVD-RW, DVD+RW, DVD-RAM, BD-RE.

     Profiles depend on drive type and media state. They are expressed as numbers. It is unfortunate that formatted CD-RW have the same profile number as unformatted ones.

     ROM drives often announce all media as ROM profiles. Some writer drives show closed sequential media as ROM profile.

     CD-ROM     0x08

     DVD-ROM    0x10

     BD-ROM     0x40

     Sequentially recordable profiles allow multisession in most cases. Special burn programs are needed for writing to them.

     CD-R       0x09

     CD-RW      0x0a (unformatted)

     DVD-R      0x11

     DVD-RW     0x14 (unformatted)

     DVD-R DL   0x15 (double layer)

     DVD-R DL   0x16 (double layer, jump recording)

     DVD+R      0x1a

     DVD+RW DL  0x2a (double layer)

     DVD+R DL   0x2b (double layer)

     BD-R       0x41 (single or double layer, formatted or not)

     HD DVD-ROM 0x50

     HD DVD-R   0x51

     HD DVD-RAM 0x52

     They can assume three states:

     "Blank" is not readable but writeable from scratch

     "Appendable" is readable and after the readable part still writeable

     "Closed" is only readable

     CD-RW and DVD-RW can be brought back to blank state, or they can be formatted to become overwriteable.

     Overwriteable profiles allow random read-write access with a granularity of 2 kB or 32 kB. One can hope for having read-write access via the normal POSIX operations lseek(), read(), write() of the operating system.

     CD-RW      0x0a (formatted)

     DVD-RAM    0x12

     DVD-RW     0x13 (formatted, 32 kB write granularity)

     DVD+RW     0x1a

     BD-R       0x42 (formatted for pseudo-random recording)

     BD-RE      0x43 (single or double layer)

     BD-R profile 0x42 is defined by MMC but not implemented by the consumer priced Blu-ray burners as of year 2010.

Mixed Mode CD

     A Mixed Mode is a CD that contains tracks of differing CD-ROM Mode formats. In particular the first track may contain both computer data (Yellow Book) CD ROM data while the remaining tracks are audio or video data. Video CD's can be Mixed Mode CDs.

Multisession

     A way of writing to a CD , DVD or Blu-ray Disc that allows more data to be added to readable discs at a later time. The media must not have been closed by the previous write session. This applies originally to unformatted CD-R, CD-RW, DVD-R, DVD-RW, DVD+R, and sequential BD-R which all can record more than one session. They hold a table-of-content with sessions and tracks. Formatted CD-RW, DVD-RAM, DVD+RW, DVD-RW, and BD-RE have only one track. Multisession on these media needs help by the recorded data formats.

     Multisession can be used to add a changeset to an existing ISO 9660 filesystem. Typically the add-on session contains a whole new filesystem tree with old and new files. It also contains the data blocks of the newly introduced or freshly overwritten files. The convention for mounting multisession ISO 9660 images is to load the superblock from the start of the first track in the last session as listed in the media table-of-content. Formatted media are assumed to have a single track starting at block 0. So ISO 9660 multisession on formatted media has to overwrite the volume descriptors at block 16 ff. with every new session. A chain of recognizable sessions can be achieved by starting the first ISO 9660 image at block 32 so that its descriptors get not overwritten later.

Nero NRG format file

     A proprietary CD image file format use by a popular program for Microsoft Windows, Ahead Nero. The specification of this format is not to our knowledge published.

Rock Ridge Extensions

     An extension to the ISO-9660 standard which adds POSIX information to files. It allows long file names, owner, group, access permissions ugo+-rwx, inode numbers, hard-link count, file types other than directory or regular file. Rock Ridge is described by unapproved standard IEEE P1282 / RRIP-1.12 and based on unapproved IEEE P1281 / SUSP-1.10. It has become a de-facto standard on X/Open systems like GNU/Linux, FreeBSD, Solaris, et.\ al.

SCSI

     Small Computer System Interface.  A set of ANSI standard electronic interfaces (originally developed at Apple Computer) that allow personal computers to communicate with peripheral hardware such as CD-ROM drives, disk drives, printers, etc.

     Although the original hardware is outdated since years, the SCSI command set nowadays controls most storage devices including all optical disc drives. The contemporary electronic technologies which transport SCSI commands to optical drives are P-ATA, SATA, and USB.

     A SCSI programming specification made by the SCSI committee T10 organization http://www.t10.org/.

     The documents libcdio makes use of are described in SCSI standards documents SCSI Primary Commands (SPC), SCSI Block Commands (SBC), and Multi-Media Commands (MMC). These documents generally have a numeric level number appended. For example SPC-3 refers to ``SCSI Primary Commands - 3'.

     In year 2010 the current versions were SPC-3, SBC-2, MMC-5.

SCSI CDB

     SCSI Command Descriptor Block. The data structure that is used to issue a SCSI command.

SCSI Pass Through Interface.

     Yet another way of issuing MMC commands for accessing a CD-ROM. As with MMC or ASPI, the CD-ROM doesn't necessarily have to be a SCSI-attached drive. See also MMC and see ASPI.

Session

     A fully readable complete recording that contains one or more tracks of computer data or audio on a CD. On a DVD or Blu-ray Disc, there are only data sessions.

SVCD

     Super VCD

     An improvement of Video CD 2.0 specification which includes most notably a switch from MPEG-1 (constant bit rate encoding) to MPEG-2 (variable bit rate encoding) for the video stream.

     Also added was higher video-stream resolution, up to 4 overlay graphics and text (OGT) sub-channels for user switchable subtitle displaying, closed caption text, and command lists for controlling the SVCD virtual machine.

     See http://www.dvdrhelp.com/svcd

TOC

     (Compact Disc) Table of Contents. The TOC contains a list of sessions and their tracks. For sessions, it records the starting track number and the last track number. For tracks it records starting time block address, size, copy protection, linear audio preemphasis, track format (CDDA or data) in that order. Session and track information is also available on sequential DVD and Blu-ray Discs. Several track properties are fixed to equivalents of CD data.

Track

     A unit of data of a CD. The size of a track can vary; it can occupy the entire contents of the CD. Most CD standards however require that tracks have a 150 frame (or ``2 second'') lead-in gap.

     An abstraction of tracks for CD, DVD and Blu-ray Discs is the Logical Track as of MMC specs. Overwriteable media have a single logical track, sequential media can have one or more logical tracks which they describe in their TOC.

UDF

     Universal Disc Format was designed as successor of ISO 9660. It allows to record long file names and advanced file properties. Although intended as format for data exchange its main importance is with DVD video players. Video DVDs have to bear a simple UDF filesystem with a prescribed set of files.

VCD

     The Video Compact Disc (Video CD or VCD) is a standardized digital video storage format. It is based on the commonly available Compact Disc technology, which allows for low-cost video authoring. Video CD's can be played in most DVD standalone player, dedicated VCD players and finally, modern Personal Computers with multimedia support.

     A Video CD is made up of CD-ROM XA sectors, i.e. CD-ROM mode 2 form 1 & 2 sectors. Non-MPEG data is stored in mode 2 form 1 sectors with a user data area of 2048 byte, which have a similar L2 error correction and detection (ECC/EDC) to CD-ROM mode 1 sectors. While real-time MPEG streams is stored in CD-ROM mode 2 form 2 sectors, which by have no L2 ECC, yield a ~14% greater user data area consisting of 2324 bytes (actually raw mode 2 sectors have a 2336 byte user data area, but parts of it are used for error codes and headers when using the mode 2 form 1 or form 2 configurations.)

     http://www.dvdrhelp.com/vcd

Win32 ASPI

     The ASPI interface specification was developed by Adaptec for sending commands to a SCSI host adapter (such as those controlling CD and DVD drives) and used on Window 9x/NT and later. Emulation for ATAPI drives was added so that the same sets of commands worked those even though the drives might not be SCSI nor might there even be a SCSI controller attached.

     However in Windows NT/2K/XP, Microsoft provides their Win32 ioctl interface, and has take steps to make using ASPI more inaccessible (e.g. requiring administrative access to use ASPI).

     See also MMC.

Win32 ioctl driver

     Ioctl (Input Output ConTroLs). A Win32 function, implemented in all Microsoft Windows.  It is used for sending commands to devices using defined codes and structures.

XA

     See CD-ROM XA.