MusicBrainz Tag

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MusicBrainz Metadata

Status: The information on this page seems to be outdated and is slightly different from the official version at PicardTagMapping

Applications that read or write metadata tags from music files should follow one consistent specification for what MusicBrainz information is stored where and in what tag. That way all the work of the various tagger applications will contribute to a well connected and clean body of metadata. Any application that deals with music should be able to read the MusicBrainzIdentifiers from a music file in order to communicate unambiguously about the music it's working with.

MusicBrainz Track Identifier

The MusicBrainz Track Id is the internal unique ID MusicBrainz defines for every object in its database.

MusicBrainz Artist Identifier

The MusicBrainz Artist Id is the ArtistID as stored in the MusicBrainz database.

MusicBrainz Album Identifier

The MusicBrainz Album Id is the AlbumID as stored in the MusicBrainz database.

MusicBrainz Album Artist Identifier

The MusicBrainz Album Artist Id is used to store an artist identifier for the album the track is on. This is only for VariousArtistsReleases where the tracks have multiple different artists and the album itself is by the special artist VariousArtists with ArtistID 89ad4ac3-39f7-470e-963a-56509c546377.

The value of this identifier is the ArtistID as stored in the MusicBrainz database.

MusicBrainz Album Status

This stores the status of the album the track is from. Possible values are, for example: official, promotional, bootleg.

MusicBrainz Album Type

This type the status of the album the track is from. Possible values are, for example: album, single, live.

MusicIP PUID Identifier

The MusicIP PUID is the track's PUID as stored in the MusicBrainz database.

MusicBrainz Metadata Tags

Overview

Metadata tags defined by MusicBrainz

Value ID3v2 Vorbis Comments MP4 (iTunes) tags Windows Media APE tags
MusicBrainz Track Id UFID:http://musicbrainz.org MUSICBRAINZ_TRACKID ----:MusicBrainz Track Id MusicBrainz/Track Id MUSICBRAINZ_TRACKID
MusicBrainz Artist Id TXXX:MusicBrainz Artist Id MUSICBRAINZ_ARTISTID ----:MusicBrainz Artist Id MusicBrainz/Artist Id MUSICBRAINZ_ARTISTID
MusicBrainz Album Id TXXX:MusicBrainz Album Id MUSICBRAINZ_ALBUMID ----:MusicBrainz Album Id MusicBrainz/Album Id MUSICBRAINZ_ALBUMID
MusicBrainz Album Artist Id TXXX:MusicBrainz Album Artist Id MUSICBRAINZ_ALBUMARTISTID ----:MusicBrainz Album Artist Id MusicBrainz/Album Artist Id MUSICBRAINZ_ALBUMARTISTID
MusicBrainz Disc Id TXXX:MusicBrainz Disc Id MUSICBRAINZ_DISCID ----:MusicBrainz Disc Id MusicBrainz/Disc Id MUSICBRAINZ_DISCID
MusicBrainz Album Status TXXX:MusicBrainz Album Status MUSICBRAINZ_ALBUMSTATUS ----:MusicBrainz Album Status MusicBrainz/Album Status MUSICBRAINZ_ALBUMSTATUS
MusicBrainz Album Type TXXX:MusicBrainz Album Type MUSICBRAINZ_ALBUMTYPE ----:MusicBrainz Album Type MusicBrainz/Album Type MUSICBRAINZ_ALBUMTYPE
MusicBrainz Album Release Country TXXX:MusicBrainz Album Release Country RELEASECOUNTRY ----:MusicBrainz Album Release Country MusicBrainz/Album Release Country
MusicIP PUID TXXX:MusicIP PUID MUSICIP_PUID ----:MusicIP PUID MusicIP/PUID MUSICIP_PUID


Other important standard metadata tags

Value ID3v2 Vorbis Comments MP4 (iTunes) tags Windows Media APE tags
Artist TPE1 ARTIST ©ART Author Artist
Album Artist TPE2 ALBUMARTIST aART WM/AlbumArtist Album Artist
Album TALB ALBUM ©alb WM/AlbumTitle Album
Title TIT2 TITLE ©nam Title Title
Track Number TRCK TRACKNUMBER trkn WM/TrackNumber Track
Release Date TYER + TDAT (2.3), TDRC (2.4) DATE ©day WM/Year Year
isCompilation TCMP COMPILATION cpil WM/IsCompilation Compilation
Album Artist Sortname TSO2 + TXXX:ALBUMARTISTSORT ALBUMARTISTSORT soaa WM/AlbumArtistSortOrder ALBUMARTISTSORT
Artist Sortname XSOP (2.3), TSOP (2.4) ARTISTSORT soar WM/ArtistSortOrder ARTISTSORT

ID3v2 Tags

See ID3v2Tags for a list of proposed frames tagger applications could write. For more information on how to use ID3v2 tags in your own applications read the specifications on http://www.id3.org/.

Note that ID3v2 frames can be stored in any order in the MP3 file.

MusicBrainz Identifiers

The MusicBrainz Track Id is stored in the special UFID frame, that contains two parts: The Owner Identifier selects the namespace where the identifies is unique. For MusicBrainz it is be guaranteed that this ID is unique on the server; therefore the default owner identifier is http://musicbrainz.org. The second part is the TrackID for the track as stored in the MusicBrainz database.

All other MusicBrainz identifiers are stored in a user defined TXXX text information frame, encoded as a 0x00 terminated ISO-8859-1 string.

General text frames

Note that for each text frame (frame names starting with a T) the encoding of the value strings can be defined in the frame header. ID3v2.3 supports UTF-16 and ISO-8859-1 encoded strings; ID3v2.4 has addional support for UTF-8 and UTF-16BE. MusicBrainz Identifiers must be encoded as ISO-8859-1 strings.

The following frames are used for the regular information from the database: TPE1 for the main artist name, TALB for the album name, TIT2 for the track title, TRCK for the track number on the album (without total number of tracks in the old MusicBrainzTagger and PicardTagger < 0.5.1 and with totals since PicardTagger 0.5.1).

Compilation frame

TCMP is a nonstandard tag that defines a track as being part of a compilation (VA album) if set to the string value "1" or part of a single artist album if set to the string value "0". It is used by the iTunes music player software.

Artist sortname frame

The artist sortname is stored in the TSOP frame for ID3v2.4 and in the experimental XSOP frame for ID3v2.3.

Release date frame

ID3v2.3 is missing a standard frame for a detailed date. Therefore the experimental XDOR frame is used and the additional TORY that stores the year of release as a 4 digit number only is used.

In ID3v2.4 only the TDRL frame is used to store the complete release date in YYYY-MM-DD format.


Vorbis Comments

In contrast to the various possibilities of ID3 tagging, Vorbis and FLAC tags are stored in a unified way. All strings are encoded as UTF-8, tagged data is stored in the so called comment header, each key value pair is specified as a tripplet of the form: [length in bytes][key]=[value]. Strings are not terminated. For proposed extensions to the default comment tags see Ogg Vorbis Comment Field Recommendations and Extending Vorbis Comments.

Note that RELEASECOUNTRY is no standard tag and not mentioned in any of the proposals; DATE was originally specified to store the recording date while MusicBrainz defines only release dates.

MP4 (iTunes) tags

There is no official MPEG standard on how to embed metadata tags in MP4 files. Apple iTunes therefore started to use their own solution in order to be able to store metadata tags. Those iTunes tags quickly became the de-facto standard for metadata tags within MP4 files.

Metadata tags within MP4 files are stored within so-called "boxes" (also known as "atoms"). Those boxes can contain other boxes as childs within them. Metadata tags to be used with iTunes come in the moov.udta.meta.ilst hierarchy. The boxes located directly under the ilst box have specific names, which are listed in the overview table above.

There also is one special metadata box: the ---- box. It has the three child boxes mean, name, and data. The mean box always carries the string "com.apple.iTunes", while the name box holds the actual metadata identifier string. If the tag table above therefore lists, for example, an MP4 tag name of "----:MusicBrainz Disc Id", then this actually means that a ---- box is used with a child name box which holds "MusicBrainz Disc Id".


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