Matroska Media Container Tag Specifications
draft-ietf-cellar-tags-05
The information below is for an old version of the document.
| Document | Type |
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|---|---|---|---|
| Authors | Steve Lhomme, Moritz Bunkus, Dave Rice | ||
| Last updated | 2020-10-19 (Latest revision 2020-04-17) | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
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| Additional resources | Mailing list discussion | ||
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draft-ietf-cellar-tags-05
cellar S. Lhomme
Internet-Draft
Intended status: Informational M. Bunkus
Expires: 22 April 2021
D. Rice
19 October 2020
Matroska Media Container Tag Specifications
draft-ietf-cellar-tags-05
Abstract
This document defines the Matroska tags, namely the tag names and
their respective semantic meaning.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 22 April 2021.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Simplified BSD License text
as described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Status of this document . . . . . . . . . . . . . . . . . . . 3
3. Security Considerations . . . . . . . . . . . . . . . . . . . 3
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3
5. Notation and Conventions . . . . . . . . . . . . . . . . . . 3
6. Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
6.1. Why official tags matter . . . . . . . . . . . . . . . . 4
6.2. Tag translations . . . . . . . . . . . . . . . . . . . . 4
6.3. Tag Formatting . . . . . . . . . . . . . . . . . . . . . 5
6.4. Target types . . . . . . . . . . . . . . . . . . . . . . 5
6.5. Official tags . . . . . . . . . . . . . . . . . . . . . . 7
6.6. Nesting Information . . . . . . . . . . . . . . . . . . . 7
6.7. Organization Information . . . . . . . . . . . . . . . . 8
6.8. Titles . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.9. Nested Information . . . . . . . . . . . . . . . . . . . 9
6.10. Entities . . . . . . . . . . . . . . . . . . . . . . . . 9
6.11. Search and Classification . . . . . . . . . . . . . . . . 11
6.12. Temporal Information . . . . . . . . . . . . . . . . . . 11
6.13. Spacial Information . . . . . . . . . . . . . . . . . . . 12
6.14. Personal . . . . . . . . . . . . . . . . . . . . . . . . 13
6.15. Technical Information . . . . . . . . . . . . . . . . . . 13
6.16. Identifiers . . . . . . . . . . . . . . . . . . . . . . . 14
6.17. Commercial . . . . . . . . . . . . . . . . . . . . . . . 15
6.18. Legal . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.19. Notes . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7. Normative References . . . . . . . . . . . . . . . . . . . . 16
8. Informative References . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
Matroska aims to become THE standard of multimedia container formats.
It can store timestamped multimedia data but also chapters and tags.
The "Tag Elements" add important metadata to identify and classify
the information found in a "Matroska Segment". It can tag a whole
"Segment", separate "Track Elements", individual "Chapter Elements"
or "Attachment Elements".
While the Matroska tagging framework allows anyone to create their
own custom tags, it's important to have a common set of values for
interoperability. This document intends to define a set of common
tag names used in Matroska.
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2. Status of this document
This document is a work-in-progress specification defining the
Matroska file format as part of the IETF Cellar working group
(https://datatracker.ietf.org/wg/cellar/charter/). It uses basic
elements and concepts already defined in the Matroska specifications
defined by this workgroup.
3. Security Considerations
"Tag" values can be either strings or binary blobs. This document
inherits security considerations from the EBML and Matroska
documents.
4. IANA Considerations
To be determined.
5. Notation and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
6. Tagging
When a Tag is nested within another Tag, the nested Tag becomes an
attribute of the base tag. For instance, if you wanted to store the
dates that a singer used certain addresses for, that singer being the
lead singer for a track that included multiple bands simultaneously,
then your tag tree would look something like this:
* Targets
- TrackUID
* BAND
- LEADPERFORMER
- ADDRESS
o DATE
o DATEEND
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- ADDRESS
o DATE
In this way, it becomes possible to store any Tag as attributes of
another tag.
Multiple items SHOULD never be stored as a list in a single
TagString. If there is more than one tag of a certain type to be
stored, then more than one SimpleTag SHOULD be used.
For authoring Tags outside of EBML, the following XML syntax is
proposed (https://www.matroska.org/files/tags/matroskatags.dtd) used
in mkvmerge (https://mkvtoolnix.download/doc/
mkvmerge.html#mkvmerge.tags). Binary data SHOULD be stored using
BASE64 encoding if it is being stored at authoring time.
6.1. Why official tags matter
There is a debate between people who think all tags SHOULD be free
and those who think all tags SHOULD be strict. If you look at this
page you will realize we are in between.
Advanced-users application might let you put any tag in your file.
But for the rest of the applications, they usually give you a basic
list of tags you can use. Both have their needs. But it's usually a
bad idea to use custom/exotic tags because you will probably be the
only person to use this information even though everyone else could
benefit from it. So hopefully, when someone wants to put information
in one's file, they will find an official one that fit them and
hopefully use it ! If it's not in the list, this person can contact
us any time for addition of such a missing tag. But it doesn't mean
it will be accepted... Matroska files are not meant the become a
whole database of people who made costumes for a film. A website
would be better for that... It's hard to define what SHOULD be in and
what doesn't make sense in a file. So we'll treat each request
carefully.
We also need an official list simply for developers to be able to
display relevant information in their own design (if they choose to
support a list of meta-information they SHOULD know which tag has the
wanted meaning so that other apps could understand the same meaning).
6.2. Tag translations
To be able to save tags from other systems to Matroska we need to
translate them to our system. There is a translation table on our
site (othertagsystems/comparetable.html).
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6.3. Tag Formatting
* The TagName SHOULD always be written in all capital letters and
contain no space.
* The fields with dates SHOULD have the following format: YYYY-MM-DD
hh:mm:ss.mss YYYY = Year, MM = Month, DD = Days, HH = Hours, mm =
Minutes, ss = Seconds, mss = Milliseconds. To store less
accuracy, you remove items starting from the right. To store only
the year, you would use, "2004". To store a specific day such as
May 1st, 2003, you would use "2003-05-01".
* Fields that require a Float SHOULD use the "." mark instead of the
"," mark. To display it differently for another local,
applications SHOULD support auto replacement on display. Also, a
thousandths separator SHOULD NOT be used.
* For currency amounts, there SHOULD only be a numeric value in the
Tag. Only numbers, no letters or symbols other than ".". For
instance, you would store "15.59" instead of "$15.59USD".
6.4. Target types
The TargetType element allows tagging of different parts that are
inside or outside a given file. For example, in an audio file with
one song you could have information about the album it comes from and
even the CD set even if it's not found in the file.
For application to know what kind of information (like TITLE) relates
to a certain level (CD title or track title), we also need a set of
official TargetType names. For now audio and video will have
different values & names. That also means the same tag name can have
different meanings depending on where it is (otherwise we would end
up with 15 TITLE_ tags).
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+=================+============+============+=======================+
| TargetTypeValue | Audio | Video | Comment |
| | strings | strings | |
+=================+============+============+=======================+
| 70 | COLLECTION | COLLECTION | the high |
| | | | hierarchy |
| | | | consisting of |
| | | | many different |
| | | | lower items |
+-----------------+------------+------------+-----------------------+
| 60 | EDITION / | SEASON / | a list of lower |
| | ISSUE / | SEQUEL / | levels grouped |
| | VOLUME / | VOLUME | together |
| | OPUS | | |
+-----------------+------------+------------+-----------------------+
| 50 | ALBUM / | MOVIE / | the most common |
| | OPERA / | EPISODE / | grouping level |
| | CONCERT | CONCERT | of music and |
| | | | video (equals |
| | | | to an episode |
| | | | for TV series) |
+-----------------+------------+------------+-----------------------+
| 40 | PART / | PART / | when an album |
| | SESSION | SESSION | or episode has |
| | | | different |
| | | | logical parts |
+-----------------+------------+------------+-----------------------+
| 30 | TRACK / | CHAPTER | the common |
| | SONG | | parts of an |
| | | | album or a |
| | | | movie |
+-----------------+------------+------------+-----------------------+
| 20 | SUBTRACK / | SCENE | corresponds to |
| | PART / | | parts of a |
| | MOVEMENT | | track for audio |
| | | | (like a |
| | | | movement) |
+-----------------+------------+------------+-----------------------+
| 10 | - | SHOT | the lowest |
| | | | hierarchy found |
| | | | in music or |
| | | | movies |
+-----------------+------------+------------+-----------------------+
Table 1
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An upper level value tag applies to the lower level. That means if a
CD has the same artist for all tracks, you just need to set the
ARTIST tag at level 50 (ALBUM) and not to each TRACK (but you can).
That also means that, if some parts of the CD have no known ARTIST,
the value MUST be set to nothing (a void string "").
When a level doesn't exist it MUST NOT be specified in the files, so
that the TOTAL_PARTS and PART_NUMBER elements match the same levels.
Here is an example of how these "organizational" tags work: If you
set 10 TOTAL_PARTS to the ALBUM level (40) it means the album
contains 10 lower parts. The lower part in question is the first
lower level that is specified in the file. So, if it's TRACK (30),
then that means it contains 10 tracks. If it's MOVEMENT (20), that
means it's 10 movements, etc.
6.5. Official tags
The following is a complete list of the supported Matroska Tags.
While it is possible to use Tag names that are not listed below, this
is not recommended as compatibility will be compromised. If you find
that there is a Tag missing that you would like to use, then please
contact the Matroska team for its inclusion in the specifications
before the format reaches 1.0.
6.6. Nesting Information
Nesting Information tags are intended to contain other tags.
+==========+======+=======================================+
| Tag Name | Type | Description |
+==========+======+=======================================+
| ORIGINAL | - | A special tag that is meant to have |
| | | other tags inside (using nested tags) |
+----------+------+---------------------------------------+
Table 2
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to describe the original work of art that this item is based on. All
tags in this list can be used "under" the ORIGINAL tag like LYRICIST,
PERFORMER, etc. SAMPLE | - | A tag that contains other tags to
describe a sample used in the targeted item taken from another work
of art. All tags in this list can be used "under" the SAMPLE tag
like TITLE, ARTIST, DATE_RELEASED, etc. COUNTRY | UTF-8 | The name
of the country ([biblio ISO-639-2](https://www.loc.gov/standards/
iso639-2/php/English (https://www.loc.gov/standards/iso639-2/php/
English)_list.php)) that is meant to have other tags inside (using
nested tags) to country specific information about the item. All
tags in this list can be used "under" the COUNTRY_SPECIFIC tag like
LABEL, PUBLISH_RATING, etc.
6.7. Organization Information
+=============+=======+=============================================+
| Tag Name | Type | Description |
+=============+=======+=============================================+
| TOTAL_PARTS | UTF-8 | Total number of parts defined |
| | | at the first lower level. |
| | | (e.g., if TargetType is ALBUM, |
+-------------+-------+---------------------------------------------+
Table 3
the total number of tracks of an audio CD) PART_NUMBER | UTF-8 |
Number of the current part of the current level. (e.g., if TargetType
is TRACK, the track number of an audio CD) PART_OFFSET | UTF-8 | A
number to add to PART_NUMBER, when the parts at that level don't
start at 1. (e.g., if TargetType is TRACK, the track number of the
second audio CD)
6.8. Titles
+==========+=======+===========================================+
| Tag Name | Type | Description |
+==========+=======+===========================================+
| TITLE | UTF-8 | The title of this item. For example, for |
| | | music you might label this "Canon in D", |
+----------+-------+-------------------------------------------+
Table 4
or for video's audio track you might use "English 5.1" This is akin
to the TIT2 tag in ID3. SUBTITLE | UTF-8 | Sub Title of the entity.
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6.9. Nested Information
Nested Information includes tags contained in other tags.
+===========+=======+===========================================+
| Tag Name | Type | Description |
+===========+=======+===========================================+
| URL | UTF-8 | URL corresponding to the tag it's |
| | | included in. |
+-----------+-------+-------------------------------------------+
| SORT_WITH | UTF-8 | A child element to indicate what |
| | | alternative value the parent tag can have |
+-----------+-------+-------------------------------------------+
Table 5
to be sorted -- for example, "Pet Shop Boys" instead of "The Pet Shop
Boys". Or "Marley Bob" and "Marley Ziggy" (no comma needed).
INSTRUMENTS | UTF-8 | The instruments that are being used/played,
separated by a comma. It SHOULD be a child of the following tags:
ARTIST, LEAD_PERFORMER, or ACCOMPANIMENT. EMAIL | UTF-8 | Email
corresponding to the tag it's included in. ADDRESS | UTF-8 | The
physical address of the entity. The address SHOULD include a country
code. It can be useful for a recording label. FAX | UTF-8 | The fax
number corresponding to the tag it's included in. It can be useful
for a recording label. PHONE | UTF-8 | The phone number
corresponding to the tag it's included in. It can be useful for a
recording label.
6.10. Entities
+==========+=======+=======================================+
| Tag Name | Type | Description |
+==========+=======+=======================================+
| ARTIST | UTF-8 | A person or band/collective generally |
| | | considered responsible for the work. |
+----------+-------+---------------------------------------+
Table 6
This is akin to the TPE1 tag in ID3 (http://id3.org/id3v2.3.0#TPE1).
LEAD_PERFORMER | UTF-8 | Lead Performer/Soloist(s). This can
sometimes be the same as ARTIST. ACCOMPANIMENT | UTF-8 |
Band/orchestra/accompaniment/musician. This is akin to the TPE2 tag
in ID3 (http://id3.org/id3v2.3.0#TPE2). COMPOSER | UTF-8 | The name
of the composer of this item. This is akin to the TCOM tag in ID3
(http://id3.org/id3v2.3.0#TCOM). ARRANGER | UTF-8 | The person who
arranged the piece, e.g., Ravel. LYRICS | UTF-8 | The lyrics
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corresponding to a song (in case audio synchronization is not known
or as a doublon to a subtitle track). Editing this value, when
subtitles are found, SHOULD also result in editing the subtitle track
for more consistency. LYRICIST | UTF-8 | The person who wrote the
lyrics for a musical item. This is akin to the TEXT (http://id3.org/
id3v2.3.0#TEXT) tag in ID3. CONDUCTOR | UTF-8 | Conductor/performer
refinement. This is akin to the TPE3 (http://id3.org/
id3v2.3.0#TPE3). DIRECTOR | UTF-8 | This is akin to the [IART tag in
RIFF][RIFF.tags]. ASSISTANT_DIRECTOR | UTF-8 | The name of the
assistant director. DIRECTOR_OF_PHOTOGRAPHY| UTF-8 | The name of the
director of photography, also known as cinematographer. This is akin
to the ICNM tag in Extended RIFF. SOUND_ENGINEER | UTF-8 | The name
of the sound engineer or sound recordist. ART_DIRECTOR | UTF-8 | The
person who oversees the artists and craftspeople who build the sets.
PRODUCTION_DESIGNER | UTF-8 | Artist responsible for designing the
overall visual appearance of a movie. CHOREGRAPHER | UTF-8 | The
name of the choregrapher COSTUME_DESIGNER | UTF-8 | The name of the
costume designer ACTOR | UTF-8 | An actor or actress playing a role
in this movie. This is the person's real name, not the character's
name the person is playing. CHARACTER | UTF-8 | The name of the
character an actor or actress plays in this movie. This SHOULD be a
sub-tag of an "ACTOR" tag in order not to cause ambiguities.
WRITTEN_BY | UTF-8 | The author of the story or script (used for
movies and TV shows). SCREENPLAY_BY | UTF-8 | The author of the
screenplay or scenario (used for movies and TV shows). EDITED_BY |
UTF-8 | This is akin to the IEDT tag in Extended RIFF. PRODUCER |
UTF-8 | Produced by. This is akin to the IPRO tag in Extended RIFF.
COPRODUCER | UTF-8 | The name of a co-producer. EXECUTIVE_PRODUCER |
UTF-8 | The name of an executive producer. DISTRIBUTED_BY | UTF-8 |
This is akin to the IDST tag in Extended RIFF. MASTERED_BY | UTF-8 |
The engineer who mastered the content for a physical medium or for
digital distribution. ENCODED_BY | UTF-8 | This is akin to the TENC
tag (http://id3.org/id3v2.3.0#TENC) in ID3. MIXED_BY | UTF-8 | DJ
mix by the artist specified REMIXED_BY | UTF-8 | Interpreted,
remixed, or otherwise modified by. This is akin to the TPE4 tag in
ID3 (http://id3.org/id3v2.3.0#TPE4). PRODUCTION_STUDIO | UTF-8 |
This is akin to the ISTD tag in Extended RIFF. THANKS_TO | UTF-8 | A
very general tag for everyone else that wants to be listed.
PUBLISHER | UTF-8 | This is akin to the TPUB tag in ID3
(http://id3.org/id3v2.3.0#TPUB). LABEL | UTF-8 | The record label or
imprint on the disc.
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6.11. Search and Classification
+==========+=======+=======================================+
| Tag Name | Type | Description |
+==========+=======+=======================================+
| GENRE | UTF-8 | The main genre (classical, ambient- |
| | | house, synthpop, sci-fi, drama, etc). |
+----------+-------+---------------------------------------+
Table 7
The format follows the infamous TCON tag in ID3. MOOD | UTF-8 |
Intended to reflect the mood of the item with a few keywords, e.g.,
"Romantic", "Sad" or "Uplifting". The format follows that of the
TMOO tag in ID3. ORIGINAL_MEDIA_TYPE | UTF-8 | Describes the
original type of the media, such as, "DVD", "CD", "computer image,"
"drawing," "lithograph," and so forth. This is akin to the TMED tag
in ID3 (http://id3.org/id3v2.3.0#TMED). CONTENT_TYPE | UTF-8 | The
type of the item. e.g., Documentary, Feature Film, Cartoon, Music
Video, Music, Sound FX, ... SUBJECT | UTF-8 | Describes the topic of
the file, such as "Aerial view of Seattle." DESCRIPTION | UTF-8 | A
short description of the content, such as "Two birds flying."
KEYWORDS | UTF-8 | Keywords to the item separated by a comma, used
for searching. SUMMARY | UTF-8 | A plot outline or a summary of the
story. SYNOPSIS | UTF-8 | A description of the story line of the
item. INITIAL_KEY | UTF-8 | The initial key that a musical track
starts in. The format is identical to ID3. PERIOD | UTF-8 |
Describes the period that the piece is from or about. For example,
"Renaissance". LAW_RATING | UTF-8 | Depending on the "COUNTRY" it's
the format of the rating of a movie (P, R, X in the USA, an age in
other countries or a URI defining a logo). ICRA | binary | The ICRA
(http://www.icra.org/) content rating for parental control.
(Previously RSACi)
6.12. Temporal Information
+================+=======+=======================================+
| Tag Name | Type | Description |
+================+=======+=======================================+
| DATE_RELEASED | UTF-8 | The time that the item was originally |
| | | released. This is akin to the TDRL |
| | | tag in ID3. |
+----------------+-------+---------------------------------------+
| DATE_RECORDED | UTF-8 | The time that the recording began. |
| | | This is akin to the TDRC tag in ID3. |
+----------------+-------+---------------------------------------+
| DATE_ENCODED | UTF-8 | The time that the encoding of this |
| | | item was completed began. This is |
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| | | akin to the TDEN tag in ID3. |
+----------------+-------+---------------------------------------+
| DATE_TAGGED | UTF-8 | The time that the tags were done for |
| | | this item. This is akin to the TDTG |
| | | tag in ID3. |
+----------------+-------+---------------------------------------+
| DATE_DIGITIZED | UTF-8 | The time that the item was |
| | | transferred to a digital medium. |
| | | This is akin to the IDIT tag in RIFF. |
+----------------+-------+---------------------------------------+
| DATE_WRITTEN | UTF-8 | The time that the writing of the |
| | | music/script began. |
+----------------+-------+---------------------------------------+
| DATE_PURCHASED | UTF-8 | Information on when the file was |
| | | purchased; see also Section 6.17 on |
| | | purchase tags. |
+----------------+-------+---------------------------------------+
Table 8
6.13. Spacial Information
+====================+=======+==============================+
| Tag Name | Type | Description |
+====================+=======+==============================+
| RECORDING_LOCATION | UTF-8 | The location where the item |
| | | was recorded. The countries |
| | | corresponding to the string, |
+--------------------+-------+------------------------------+
Table 9
same 2 octets as in Internet domains (https://www.iana.org/whois), or
possibly ISO-3166 (https://www.iso.org/iso-3166-country-codes.html).
This code is followed by a comma, then more detailed information such
as state/province, another comma, and then city. For example, "US,
Texas, Austin". This will allow for easy sorting. It is okay to
only store the country, or the country and the state/province. More
detailed information can be added after the city through the use of
additional commas. In cases where the province/state is unknown, but
you want to store the city, simply leave a space between the two
commas. For example, "US, , Austin". COMPOSITION_LOCATION | UTF-8 |
Location that the item was originally designed/written. The
countries corresponding to the string, same 2 octets as in Internet
domains (https://www.iana.org/whois), or possibly ISO-3166
(https://www.iso.org/iso-3166-country-codes.html). This code is
followed by a comma, then more detailed information such as state/
province, another comma, and then city. For example, "US, Texas,
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Austin". This will allow for easy sorting. It is okay to only store
the country, or the country and the state/province. More detailed
information can be added after the city through the use of additional
commas. In cases where the province/state is unknown, but you want
to store the city, simply leave a space between the two commas. For
example, "US, , Austin". COMPOSER_NATIONALITY | UTF-8 | Nationality
of the main composer of the item, mostly for classical music. The
countries corresponding to the string, same 2 octets as in Internet
domains (https://www.iana.org/whois), or possibly ISO-3166
(https://www.iso.org/iso-3166-country-codes.html).
6.14. Personal
+==============+=======+===============================+
| Tag Name | Type | Description |
+==============+=======+===============================+
| COMMENT | UTF-8 | Any comment related to the |
| | | content. |
+--------------+-------+-------------------------------+
| PLAY_COUNTER | UTF-8 | The number of time the item |
| | | has been played. |
+--------------+-------+-------------------------------+
| RATING | UTF-8 | A numeric value defining how |
| | | much a person likes the song/ |
| | | movie. The number is between |
+--------------+-------+-------------------------------+
Table 10
0 and 5 with decimal values possible (e.g., 2.7), 5(.0) being the
highest possible rating. Other rating systems with different ranges
will have to be scaled.
6.15. Technical Information
+==================+=======+=======================================+
| Tag Name | Type | Description |
+==================+=======+=======================================+
| ENCODER | UTF-8 | The software or hardware used to |
| | | encode this item. ("LAME" or "XviD") |
+------------------+-------+---------------------------------------+
| ENCODER_SETTINGS | UTF-8 | A list of the settings used for |
| | | encoding this item. No specific |
| | | format. |
+------------------+-------+---------------------------------------+
| BPS | UTF-8 | The average bits per second of the |
| | | specified item. This is only the |
| | | data in the Blocks, |
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+------------------+-------+---------------------------------------+
Table 11
and excludes headers and any container overhead. FPS | UTF-8 | The
average frames per second of the specified item. This is typically
the average number of Blocks per second. In the event that lacing is
used, each laced chunk is to be counted as a separate frame. BPM |
UTF-8 | Average number of beats per minute in the complete target
(e.g., a chapter). Usually a decimal number. MEASURE | UTF-8 | In
music, a measure is a unit of time in Western music like "4/4". It
represents a regular grouping of beats, a meter, as indicated in
musical notation by the time signature. The majority of the
contemporary rock and pop music you hear on the radio these days is
written in the 4/4 time signature. TUNING | UTF-8 | It is saved as a
frequency in hertz to allow near-perfect tuning of instruments to the
same tone as the musical piece (e.g., "441.34" in Hertz). The
default value is 440.0 Hz. REPLAYGAIN_GAIN | binary | The gain to
apply to reach 89dB SPL on playback. This is based on the Replay
Gain standard (http://www.replaygain.org/). Note that ReplayGain
information can be found at all TargetType levels (track, album,
etc). REPLAYGAIN_PEAK | binary | The maximum absolute peak value of
the item. This is based on the Replay Gain standard
(http://www.replaygain.org/).
6.16. Identifiers
+======+=======+======================================+
| Tag | Type | Description |
| Name | | |
+======+=======+======================================+
| ISRC | UTF-8 | The International Standard Recording |
| | | Code (http://www.ifpi.org/isrc/ |
| | | isrc_handbook.html#Heading198), |
+------+-------+--------------------------------------+
Table 12
excluding the "ISRC" prefix and including hyphens. MCDI | binary |
This is a binary dump of the TOC of the CDROM that this item was
taken from. This holds the same information as the MCDI in ID3.
ISBN | UTF-8 | International Standard Book Number (https://www.isbn-
international.org/) BARCODE | UTF-8 | EAN-13
(https://www.gs1.org/standards/barcodes/ean-upc) (European Article
Numbering) or UPC-A (http://www.uc-council.org/) (Universal Product
Code) bar code identifier CATALOG_NUMBER | UTF-8 | A label-specific
string used to identify the release -- for example, TIC 01.
LABEL_CODE | UTF-8 | A 4-digit or 5-digit number to identify the
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record label, typically printed as (LC) xxxx or (LC) 0xxxx on CDs
medias or covers (only the number is stored). LCCN | UTF-8 | Library
of Congress Control Number (https://www.loc.gov/marc/lccn.html)
IMDB | UTF-8 | Internet Movie Database (IMDb) (https://www.imdb.com/)
identifier. "tt" followed by at least 7 digits for Movies, TV Shows,
and Episodes. TMDB | UTF-8 | The Movie Database (TMDb)
(https://www.themoviedb.org/) identifier. The variable length digits
string MUST be prefixed with either "movie/" or "tv/". TVDB |
UTF-8 | The TV Database (TheTVDB) (https://www.thetvdb.com/)
identifier. Variable length all-digits string identifying a TV Show.
6.17. Commercial
+================+=======+=========================================+
| Tag Name | Type | Description |
+================+=======+=========================================+
| PURCHASE_ITEM | UTF-8 | URL to purchase this file. This is |
| | | akin to the WPAY tag in ID3. |
+----------------+-------+-----------------------------------------+
| PURCHASE_INFO | UTF-8 | Information on where to purchase this |
| | | album. This is akin to the WCOM tag in |
| | | ID3. |
+----------------+-------+-----------------------------------------+
| PURCHASE_OWNER | UTF-8 | Information on the person who purchased |
| | | the file. This is akin to the TOWN tag |
| | | in ID3 (http://id3.org/id3v2.3.0#TOWN). |
+----------------+-------+-----------------------------------------+
| PURCHASE_PRICE | UTF-8 | The amount paid for entity. There |
| | | SHOULD only be a numeric value in here. |
| | | Only numbers, |
+----------------+-------+-----------------------------------------+
Table 13
no letters or symbols other than ".". For instance, you would store
"15.59" instead of "$15.59USD". PURCHASE_CURRENCY | UTF-8 | The
currency type used to pay for the entity. Use ISO-4217
(https://www.xe.com/iso4217.php) for the 3 letter currency code.
6.18. Legal
+======================+=======+=================================+
| Tag Name | Type | Description |
+======================+=======+=================================+
| COPYRIGHT | UTF-8 | The copyright information as |
| | | per the copyright holder. This |
| | | is akin to the TCOP tag in ID3. |
+----------------------+-------+---------------------------------+
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| PRODUCTION_COPYRIGHT | UTF-8 | The copyright information as |
| | | per the production copyright |
| | | holder. This is akin to the |
| | | TPRO tag in ID3. |
+----------------------+-------+---------------------------------+
| LICENSE | UTF-8 | The license applied to the |
| | | content (like Creative Commons |
| | | variants). |
+----------------------+-------+---------------------------------+
| TERMS_OF_USE | UTF-8 | The terms of use for this item. |
| | | This is akin to the USER tag in |
| | | ID3. |
+----------------------+-------+---------------------------------+
Table 14
6.19. Notes
* In the Target list, a logical OR is applied on all tracks, a
logical OR is applied on all chapters. Then a logical AND is
applied between the Tracks list and the Chapters list to know if
an element belongs to this Target.
7. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
8. Informative References
[RIFF.tags]
Exiftool, "RIFF Tags",
<https://sno.phy.queensu.ca/~phil/exiftool/TagNames/
RIFF.html>.
Authors' Addresses
Steve Lhomme
Email: slhomme@matroska.org
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Moritz Bunkus
Email: moritz@bunkus.org
Dave Rice
Email: dave@dericed.com
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