Metadata for Called Folk Dances
draft-swhited-contra-tags-05
This document is an Internet-Draft (I-D).
Anyone may submit an I-D to the IETF.
This I-D is not endorsed by the IETF and has no formal standing in the
IETF standards process.
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Sam Whited | ||
| Last updated | 2026-08-20 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Additional resources |
Issue Tracker
Codeberg Original document |
||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-swhited-contra-tags-05
Internet Engineering Task Force ssw. Whited, Ed.
Internet-Draft Atlanta Contra Dancers
Intended status: Informational 20 August 2026
Expires: 21 February 2027
Metadata for Called Folk Dances
draft-swhited-contra-tags-05
Abstract
This document defines metadata tags for describing aspects of Contra,
Square, and other traditional called folk dances. These tags are
meant for archivists as well as modern day callers of traditional
dances.
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 21 February 2027.
Copyright Notice
Copyright (c) 2026 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.
Whited Expires 21 February 2027 [Page 1]
Internet-Draft Contra Tags August 2026
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Assigned Tags . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Called Tracks . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Called or Uncalled Tracks . . . . . . . . . . . . . . . . 4
2.3. Special Values . . . . . . . . . . . . . . . . . . . . . 6
3. Use in other tagging systems . . . . . . . . . . . . . . . . 6
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7
6. Normative References . . . . . . . . . . . . . . . . . . . . 7
7. Informative References . . . . . . . . . . . . . . . . . . . 8
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8
1. Introduction
Many traditional folk dances including Contra Dance, Square Dance,
English Country Dance (ECD), and others from a variety of cultural
backgrounds involve a caller who leads the dance by speaking or
singing the choreography in time to the music. The caller will help
the dancers perform the choreography until either the music that is
pre-selected for a particular dance ends or until the caller decides
to stop depending on the dance style.
For archivists or modern callers selecting recordings of called
dances there are a number of properties of the music and calling that
are not described by traditional music metadata that may be desirable
to know. For example, an archivist may want to find all recordings
of a specific caller playing with a specific band, but the callers
name is not a commonly used metadata tag. Or a caller may want to
filter out all tracks that already contain calls or are "crooked"
(ie. don't perfectly align with the phrasing of the particular dance
they are calling) to select recordings to call to when a live band is
not available for a dance.
Having a set of standardized tags to describe such dances makes it
easier for software meant for callers or archivists to display such
information in a standard, searchable, way. The justification for
assigned tags in Section 3.1 of [I-D.ietf-cellar-tags] also applies
to this document.
This document only aims to cover tags specifically related to called
folk dances. More general tags that may complement the tags in this
document are defined in [I-D.ietf-cellar-tags].
Whited Expires 21 February 2027 [Page 2]
Internet-Draft Contra Tags August 2026
1.1. Requirements Language
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.
2. Assigned Tags
2.1. Called Tracks
The tags defined in the following table describe recordings that
include sung or spoken dance calls.
Some recordings include separate tracks for the caller and the band
or contain an entire evening of dances in a single file delineated by
a Cue track. To facilitate these use cases, these tags SHOULD set a
target ([RFC9559], Section 24.2) referencing the track containing the
calls.
+=====================+=======+=====================================+
| Tag Name | Type | Description |
+=====================+=======+=====================================+
| DANCE_FORM | UTF-8 | The form of the folk dance such |
| | | as "contra" or "square". Because |
| | | a large number of different folk |
| | | dances exist (and because this |
| | | tag may be broadly useful for |
| | | dances other than called folk |
| | | dances) no particular format or |
| | | list of dance forms is defined. |
| | | Archivists may choose to be much |
| | | more particular about this tag, |
| | | for example listing the specific |
| | | formation of a contra dance such |
| | | as "duple minor improper contra" |
| | | while a caller may simply list |
| | | the dance as "contra". |
+---------------------+-------+-------------------------------------+
| DANCE_CALLER | UTF-8 | The name of the caller heard in |
| | | the track. This MAY be the |
| | | special value "[unknown]" (see |
| | | Section 2.3). |
+---------------------+-------+-------------------------------------+
| DANCE_TITLE | UTF-8 | The name of the dance being |
| | | called. This MAY be the special |
| | | value "[unknown]" (see |
Whited Expires 21 February 2027 [Page 3]
Internet-Draft Contra Tags August 2026
| | | Section 2.3). |
+---------------------+-------+-------------------------------------+
| DANCE_CHOREOGRAPHER | UTF-8 | The name of the author of the |
| | | dance being called. This MAY be |
| | | one of the special values |
| | | "[unknown]" or "[traditional]" |
| | | (see Section 2.3). |
+---------------------+-------+-------------------------------------+
| DANCE_CHOREOGRAPHY | UTF-8 | The moves of the dance in plain |
| | | text format. No exact style is |
| | | specified. The dance title, |
| | | choreographer, or other |
| | | information that can be |
| | | represented by other tags in this |
| | | document SHOULD NOT be included |
| | | and should instead be read from |
| | | the appropriate tags. |
+---------------------+-------+-------------------------------------+
| DANCE_ROLES | UTF-8 | Role terms used in the calls. |
| | | For example, "Larks/Robins" or |
| | | "Leads/Follows" or "Positional" |
| | | for dances that explicitly do not |
| | | mention role terms for a |
| | | partnership. No specific format |
| | | is defined. |
+---------------------+-------+-------------------------------------+
| DANCE_LICENSE | UTF-8 | Like the LICENSE field defined in |
| | | Section 4.13 of |
| | | [I-D.ietf-cellar-tags] except |
| | | relating to the choreography of |
| | | the dance being called. |
+---------------------+-------+-------------------------------------+
Table 1: Tags for tracks with calls
2.2. Called or Uncalled Tracks
The following tags are generally applicable to tracks that include
the caller as well as to tracks that are uncalled but fit the form of
a particular folk dance or are commonly used for folk dance. If the
file contains multiple audio tracks these tags SHOULD set a target
pointing to the track containing the caller.
Whited Expires 21 February 2027 [Page 4]
Internet-Draft Contra Tags August 2026
+================+=======+==========================================+
| Tag Name | Type | Description |
+================+=======+==========================================+
| DANCE_INTRO | UTF-8 | The number of intro beats (not bars) |
| | | before the dance starts and before any |
| | | potatoes. For example, if a dance had |
| | | a 28 beat introductory phrase followed |
| | | by 4 traditional potatoes before the |
| | | first time through the dance, this tag |
| | | would be set to 28 and DANCE_POTATOES |
| | | would be set to 4. If a tune had an 8 |
| | | beat intro and no traditional potatoes |
| | | this would be set to 8 and |
| | | DANCE_POTATOES would be set to 0 or |
| | | unset. |
+----------------+-------+------------------------------------------+
| DANCE_POTATOES | UTF-8 | "Potatoes" are a term used to describe |
| | | the synchronization beats played by |
| | | the band before the tune starts to get |
| | | the caller and dancers on time. This |
| | | tag is the number of beats (not bars) |
| | | leading up to the first time through |
| | | the dance. |
+----------------+-------+------------------------------------------+
| DANCE_START | UTF-8 | The start time (in milliseconds) of |
| | | the first time through the dance. |
| | | This is where the dancers would start |
| | | moving, not where the caller would |
| | | start calling. |
+----------------+-------+------------------------------------------+
| DANCE_TIMES | UTF-8 | The number of complete times through |
| | | the dance excluding any intro, outro, |
| | | or potatoes. The exact definition |
| | | will depend on the type of dance. For |
| | | example, a contra dance has 64 beat |
| | | (32 bar) phrases so the number of |
| | | times through the dance will be the |
| | | number of beats of music (excluding |
| | | intros, outros, and any crooked |
| | | phrasing) divided by 64. |
+----------------+-------+------------------------------------------+
| DANCE_CROOKED | UTF-8 | Whether the dance is a "crooked" tune |
| | | (ie. not in perfect dance form). If |
| | | set, this key MUST always be the value |
| | | "TRUE" or "FALSE". |
+----------------+-------+------------------------------------------+
| DANCE_ISSONG | UTF-8 | Whether the track is a song (has sung |
| | | vocal lyrics other than the calls) or |
Whited Expires 21 February 2027 [Page 5]
Internet-Draft Contra Tags August 2026
| | | a tune (instrumental only). If set, |
| | | this key MUST always be the value |
| | | "TRUE" or "FALSE". |
+----------------+-------+------------------------------------------+
Table 2: Tags for any track
2.3. Special Values
Several tags that take free-form text may also have certain special
values such as "[unknown]" or "[traditional]" as described above. In
software that displays this metadata these values MAY be shown as a
different, localizable, string.
The value "[unknown]", where permitted, indicates that the value of
the tag should be displayed but is currently unknown. This is
different from an unset tag which conveys no semantic meaning.
The value "[traditional]", where permitted, indicates that the
authorship of the dance is part of a folk tradition and no particular
author or authors can be assigned to it.
3. Use in other tagging systems
Though these tags were defined for use with Matroska files, they may
be used in other common tagging systems such as Vorbis Comments
[Vorbis] and in systems which re-use Vorbis Comments such as FLAC
[RFC9639] tags. No changes to the tag names or values are required
to use these tags in Vorbis Comments.
These tags may be useful in other common tagging systems such as ID3
or APE where they can also likely be used without modification,
however, their exact use in such systems is not defined in this
document.
4. IANA Considerations
This memo modifies the "Matroska Tag Names" registry defined in
Section 6.1 of [I-D.ietf-cellar-tags] to add the following values:
Whited Expires 21 February 2027 [Page 6]
Internet-Draft Contra Tags August 2026
+=====================+==========+============================+
| Tag Name | Tag Type | Reference |
+=====================+==========+============================+
| DANCE_FORM | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_CALLER | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_TITLE | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_CHOREOGRAPHER | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_CHOREOGRAPHY | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_ROLES | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_LICENSE | UTF-8 | This document, Section 2.1 |
+---------------------+----------+----------------------------+
| DANCE_INTRO | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
| DANCE_POTATOES | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
| DANCE_START | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
| DANCE_TIMES | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
| DANCE_CROOKED | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
| DANCE_ISSONG | UTF-8 | This document, Section 2.2 |
+---------------------+----------+----------------------------+
Table 3: Additions to the "Matroska Tag Names" Registry
5. Security Considerations
This document does not affect the security of the internet.
6. 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>.
Whited Expires 21 February 2027 [Page 7]
Internet-Draft Contra Tags August 2026
[RFC9559] Lhomme, S., Bunkus, M., and D. Rice, "Matroska Media
Container Format Specification", RFC 9559,
DOI 10.17487/RFC9559, October 2024,
<https://www.rfc-editor.org/info/rfc9559>.
7. Informative References
[RFC9639] van Beurden, M.Q.C. and A. Weaver, "Free Lossless Audio
Codec (FLAC)", RFC 9639, DOI 10.17487/RFC9639, December
2024, <https://www.rfc-editor.org/info/rfc9639>.
[I-D.ietf-cellar-tags]
Lhomme, S., Bunkus, M., and D. Rice, "Matroska Media
Container Tag Specifications", Work in Progress, Internet-
Draft, draft-ietf-cellar-tags-25, 3 May 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-cellar-
tags-25>.
[Vorbis] Xiph.Org, "Ogg Vorbis I format specification: comment
field and header specification",
<https://xiph.org/vorbis/doc/v-comment.html>.
Acknowledgements
Thanks to Joe Harrington for his perspective as both a contra dance
caller and DJ on the Shared Weight mailing list.
Author's Address
Sam Whited (editor)
Atlanta Contra Dancers
Atlanta, GA
United States of America
Email: sam@samwhited.com
URI: https://blog.samwhited.com
Whited Expires 21 February 2027 [Page 8]