Difference between revisions of "Metatag Mapping"

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(Introduction)
(Introduction)
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Hopefully this will help those trying to transcode or move audio data around and wish to retain their tags.
 
Hopefully this will help those trying to transcode or move audio data around and wish to retain their tags.
 
It is also hopefully of use to developers that read and write metadata from files.
 
It is also hopefully of use to developers that read and write metadata from files.
And this page helps standards bodies to make decisions on current or future metadata/formats/tags then that is just awesome too.
+
And if this page helps standards bodies to make decisions on current or future metadata/formats/tags then that is just awesome too.
  
 
The terms metadata/tag/field may be used intermittently on this page to mean the same thing. This page is also far from complete and may never be.
 
The terms metadata/tag/field may be used intermittently on this page to mean the same thing. This page is also far from complete and may never be.

Revision as of 03:41, 14 August 2013

Introduction

The purpose of this page is to try and cover as many of the most used formats/standards of tagging (audio) as possible. Hopefully this will help those trying to transcode or move audio data around and wish to retain their tags. It is also hopefully of use to developers that read and write metadata from files. And if this page helps standards bodies to make decisions on current or future metadata/formats/tags then that is just awesome too.

The terms metadata/tag/field may be used intermittently on this page to mean the same thing. This page is also far from complete and may never be.

Standard Tags

The following tables just map tags in one format/standard to another. Each format may have limitations, like not being able to handle UTF8 for example, or limitations as to the length of the content of a tag, some might have a non-textual tag like ID3v1 has for the Genre tag. These format limitations may or may not be mentioned on this page, so please keep that in mind. If you see a question mark inside the tables then that just means somebody haven't filled/researched anything about that part yet, if you see n/a in the table that means this tag does not exist and will most likely never exist for that format/standard (mostly this applies to ID3 v1 and v1.1). The grouping of the tags may also change from time to time as this page is improved.

Primary

These are the core meta-tags and supported/defined in all major tagging standards or file formats one way or another.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3 / ID3 v2.4 APEv2 Matroska WMA MP4/iTunes
Album Album ALBUM TALB Album TITLE [1] WM/AlbumTitle ©alb
Artist Artist ARTIST TPE1 Artist ARTIST Author ©art
Comment Comment DESCRIPTION COMM Comment COMMENT Description ©cmt
Date Year DATE [2] TDRC [3] Year DATE_RELEASE WM/Year ©day
Genre Genre [4] GENRE TCON Genre GENRE WM/Genre ©gen
Title Title TITLE TIT2 Title TITLE [1] Title ©nam
Track [5] Album track [6] TRACKNUMBER TRCK Track TRACK TRACKNUMBER trkn

Secondary

These meta-tags provide information that a user or software may expect. Not all formats or software may support these tags though.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4/iTunes
Composer n/a COMPOSER TCOM Composer COMPOSER WM/Composer ©wrt
Copyright n/a COPYRIGHT TCOP Copyright COPYRIGHT Copyright cprt
Disc n/a DISCNUMBER TPOS ? PART_OFFSET ? disk
ISRC n/a ISRC TSRC ISRC ISRC WM/ISRC ?
UPC/EAN n/a ? ? EAN/UPC BARCODE ? ?
Location n/a LOCATION ? Record Location RECORDING_LOCATION ? ?
Publisher n/a ORGANIZATION TPUB Publisher PUBLISHER WM/Publisher ?
ReplayGain Gain n/a REPLAYGAIN_TRACK_GAIN TXXX=REPLAYGAIN_TRACK_GAIN [7] REPLAYGAIN_TRACK_GAIN REPLAYGAIN_GAIN [1] ? ?
ReplayGain Peak n/a REPLAYGAIN_TRACK_PEAK TXXX=REPLAYGAIN_TRACK_PEAK [7] REPLAYGAIN_TRACK_PEAK REPLAYGAIN_PEAK [1] ? ?
ReplayGain Album Gain n/a REPLAYGAIN_ALBUM_GAIN TXXX=REPLAYGAIN_ALBUM_GAIN [7] REPLAYGAIN_ALBUM_GAIN REPLAYGAIN_GAIN [1] ? ?
ReplayGain Album Peak n/a REPLAYGAIN_ALBUM_PEAK TXXX=REPLAYGAIN_ALBUM_PEAK [7] REPLAYGAIN_ALBUM_PEAK REPLAYGAIN_PEAK [1] ? ?
Subtitle n/a VERSION TSST Subtitle SUBTITLE WM/Subtitle ?
Remixed By n/a REMIXEDBY TPE4 ? REMIXED_BY ? ?

Tertiary

These meta-tags while considered standard may have uneven support across various software or formats. They should otherwise be rather well specified though.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4/iTunes
Performer n/a PERFORMER ? ? ? ? ?
Total Discs n/a TOTALDISCS / DISCTOTAL ? ? ? ? ?
Total Tracks n/a TOTALTRACKS / TRACKTOTAL ? ? TOTAL_PARTS TRACKTOTAL ?
Album Artist n/a ? TPE2 ? ACCOMPANIMENT WM/AlbumArtist ?
Artist Sort n/a ? TSOP ? SORT_WITH ? ?
Contact n/a CONTACT ? ? ? ? ?

Quaternary

These meta-tags are the more rare ones. They may also be ambiguous on how the content of a tag is to be treated/parsed. Some of these may have been proprietary at some point in the past. While others may be falling into obscurity.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4
License n/a LICENSE ? ? ? ? ?

(Unsorted/Incomplete)

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4
Album Sort n/a ? TSOA ? ? ?
Album Artist Sort n/a ? TSO2 ? ? ?
BPM n/a ? TBPM ? ? ?
Compilation n/a ? TCMP ? ? ?
Composer Sort n/a ? TSOC ? ? ?
Conductor n/a ? TPE3 ? ? ?
Content Group n/a ? TIT1 ? ? ?
Encoded By n/a ENCODEDBY TENC ? ? ?
Encoding Settings n/a ? TSSE ? ? ?
Encoding Time n/a ? TDEN [8] ? ? ?
File Owner n/a ? TOWN ? ? ?
File Type n/a ? TFLT ? ? ?
Initial Key n/a ? TKEY ? ? ?
Involved People n/a ? IPLS, TIPL ? ? ?
Language n/a ? TLAN ? ? ?
Length n/a ? TLEN ? ? ?
Lyricist n/a ? TEXT ? ? ?
Media Type n/a ? TMED ? ? ?
Mood n/a ? TMOO [8] ? ? ?
Musician Credits n/a ? TMCL [8] ? ? ?
Net Radio Owner n/a ? TRSO ? ? ?
Net Radio Station n/a ? TRSN ? ? ?
Original Album n/a ? TOAL ? ? ?
Original Filename n/a ? TOFN ? ? ?
Original Lyricist n/a ? TOLY ? ? ?
Podcast n/a ? PCST ? ? ?
Podcast Category n/a ? TCAT ? ? ?
Podcast Description n/a ? TDES ? ? ?
Podcast ID n/a ? TGID ? ? ?
Podcast URL n/a ? WFED ? ? ?
Rating n/a ? POPM ? ? ?
Release Time n/a ? TDRL ? ? ?
Set Subtitle n/a ? TSST [8] ? ? ?
Tagging Time n/a ? TDTG [8] ? ? ?
Lyrics n/a ? USLT ? ? ?
URL n/a ? WXXX ? ? ?
Author URL n/a ? WOAR ? ? ?
Audio File URL n/a ? WOAF ? ? ?
Audio Source URL n/a ? WOAS ? ? ?
Promotion URL n/a ? WCOM ? ? ?
Copyright URL n/a ? WCOP ? ? ?
Payment URL n/a ? WPAY ? ? ?
Publisher URL n/a ? WPUB ? ? ?
Radio URL n/a ? WORS ? ? ?
Original Artist n/a ORIGARTIST TOPE ? ? ?

Non-standard Tags

Proprietary

These meta-tags are used in proprietary software, and is rarely of use outside that particular software.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4/iTunes
fieldname n/a ? ? ? ? ? ?
fieldname n/a ? ? ? ? ? ?

Proposed

These meta-tags are suggestions for new standards, some of these may also have previously been experimental or proprietary in nature. While they may be proposed this does not guarantee they will become standard. It just means that someone (and hopefully more than one individual) would like to see it standardized. Any tags listed here should be properly documented someplace and specified in detail.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4/iTunes
fieldname n/a ? ? ? ? ? ?
fieldname n/a ? ? ? ? ? ?

Experimental

These meta-tags are experimental in nature and should not be encountered normally, but in case they are they are listed here for completeness sake. These tags may appear and vanish at any time or may have their meaning or use changed at any time.

Tag ID3 v1/v1.1 FLAC/Vorbis/Ogg ID3 v2.3/v2.4 APEv2 Matroska WMA MP4/iTunes
Custom n/a ? TXXX ? ? ? ?

Additional Information

Notes

  1. 1.0 1.1 1.2 1.3 1.4 1.5 In Matroska it matters where the tags are used. So a ReplayGain tag for Track and Album are named the same just as an example.
  2. ISO 8601 date used/highly advised, see Vorbis Comment and ISO 8601 Wikipedia article for more.
  3. The ID3 v2.3 tags TYER & TDAT & TIME & TRDA are replaced by TDRC in ID3 v2.4, see ID3 Wikipedia article for more.
  4. The ID3 v1 and v1.1 Genre tag is a number referencing a pre-defined list, this brings it own huge genre mapping issue that is not covered in this Wiki page.
  5. Some Track meta tags may have both the current track and total tracks stored, using a / to separate the two values. While others do not.
  6. Difference between ID3 v1 and v1.1 is the addition of Album track, see ID3v1 specs for more.
  7. 7.0 7.1 7.2 7.3 Tags that start with TXXX= in the tables above means that the actual tag is stored inside a TXXX tag.
  8. 8.0 8.1 8.2 8.3 8.4 Some tags are only in ID3 v2.4 and there exists no equivalent in ID3 v2.3.

Issues

There are a few issues that are unresolved/need to be resolved:

  • "Remixed By" is pretty much the same as "Subtitle", the Ogg definition of "Version" even mention this. But ID3v2.x treat them as two separate tags.
  • "Subtitle" is often put as part of the title inside parenthesis. For display purposes that is probably correct, but not when storing the information.
  • It is not clear yet if this page should be all exhaustive, or if it should cover common practice (in a similar vein to how HTML5 standard is being maintained).

Links