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.
The specification for CD-Text was included in the Multi-Media Commands Set 3 R01 standard, released in September 1996 and backed by Sony. It was also added to new revisions of the Red Book. The actual text is stored in a format compatible with Interactive Text Transmission System, defined in the IEC 61866 standard. The ITTS standard is also applied in the MiniDisc format, as well as in Digital Audio Broadcasting technology and Digital Compact Cassette.

Storage

The CD-Text information is stored in the subchannels R to W on the disc. This information is usually stored in the subchannels in the lead-in area of the disc, where there is roughly five kilobytes of space available. It can also be stored on the main program area of the disc, which can store about 31 megabytes. Since the R to W channels are not used in the Red Book specification of audio CDs, they are not read by all CD players, which prevents some devices from reading CD-Text information.

Format

MMC-3 specifies 16 types. Of these, three are reserved and therefore they don't have keywords.
KeywordDescriptionSectionFormat
ARRANGERName of the arrangerAnyCharacter
COMPOSERName of the composerAnyCharacter
DISK_IDDisc Identification informationAnyBinary
GENREGenre Identification and Genre informationAnyBinary
ISRCISRC Code of each trackTrackCharacter
MESSAGEMessage from the content provider and/or artistAnyCharacter
PERFORMERName of the performerAnyCharacter
SONGWRITERName of the songwriterAnyCharacter
TITLETitle of album name or Track TitlesAnyCharacter
TOC_INFOTable of Content informationAnyBinary
TOC_INFO2Second Table of Content informationAnyBinary
UPC_EANUPC/EAN code of the albumDiscCharacter
SIZE_INFOSize information of the BlockAnyBinary

The character encoding is not specified, and there is no provision for indicating in the CD-Text data which encoding is in use. The original Sony authoring tools and specifications supported ASCII and two of its supersets, ISO-8859-1 and "MS-JIS". Annex J of the MMC-2 specification mentions only ASCII, but provides for "double byte character codes" to be indicated.