User:JFoliot/Issue194 Recap

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ISSUE-194: Provide a mechanism for associating a full transcript with an audio or video element.

ISSUE-194: Provide a mechanism for associating a full transcript with an audio or video element

Summary

Full transcripts give people with disabilities a way to access audio/video content. Transcripts are often provided as a separate resource, because they're often too lengthy to be included on the same page as the audio/video they're associated with.

A mechanism that creates an association between an audio/video element and a full (off page) transcript would have many benefits. These include discoverability for assistive technology users, programmatic identification for search engine indexing, design aesthetic, and content syndication or embedding.

The Requirements

R1: Discoverability - the end user (sighted or otherwise) can discover that there is a transcript available; machines (AT, search engines, syndication) can discover that there is a transcript available.

R2: Choice to consume - the option to consume or not consume the transcript remains in the control of the user.

R3: Rich text transcripts - transcripts should be able to support richer content than flat text, including WebVTT files, HTML, RTF, Daisy or other formats.

R4: Design aesthetics - the transcript display needs to be stylable for design aesthetic, including the possibility to include it in the video controls.

R5: Embeddable - the transcript needs to be embeddable, i.e. given as a separate resource, but rendered full-text on-page.

R6: Fullscreen support - the transcript needs to be able to go fullscreen with the media element

R7: Retrofitting - it should be easy for authors who are already publishing content with transcripts to retrofit their existing pages.

R8: No link duplication - transcript link duplication should be avoided.

R9: Multiple transcripts - transcripts may be available in different languages - making multiple links available should be possible.

R10: Stand alone transcripts - transcripts need to be available even in browsers that do not support or do not render audio or video elements. In fact, it should be possible to render transcripts without requiring a media element be present on the same page.

  • One significant concern that surfaced during our discussions was the 'orphaning' of the link to the transcript, which is a real possibility when copying and pasting a <video> element that only links to an IDREF (which might be to a link to the Transcript).

Change Proposals

Introduction of a <transcript> element
(http://www.w3.org/html/wg/wiki/ISSUE-194/TranscriptElement) (11 June 2012)

Author: Media Subgroup of HTML Accessibility Task Force (In particular: Silvia Pfeiffer (Google), John Foliot, Janina Sajka, Charles McCathieNevile)

This is a proposal to address the need for video and audio transcripts through introduction of a <transcript> element and a @transcript attribute on HTML5 media elements. It is based on an analysis of use cases for video transcripts and proposes a machine-discoverable, unified approach to realizing them with a dedicated rendering area for the transcript / transcript link.

Obsoletes the following Change Proposals:


This CP remains:

Mint a transcript attribute for the programmatic association of transcripts with media elements
(http://www.w3.org/html/wg/wiki/User:Eoconnor/ISSUE-194-2B) (12 July 2012)

In order to programmatically associate media elements with transcripts, we should use a transcript="" attribute which may take zero or more IDREFs to elements elsewhere in the document.

Concern

From an accessibility perspective we cannot go past Last Call with a known defect, and we've stated since the summer of 2010 that a requirement for a programmatic linkage of the transcript to the media elements was required:

"[T-1] Support the provisioning of a full text transcript for the media asset in a separate but linked resource, where the linkage is programmatically accessible to AT." http://www.w3.org/WAI/PF/media-accessibility-reqs/#transcripts


In our working draft Checklist (established at the same time as the user-requirements document), we further mapped this requirement to a current WCAG 2 "A" level requirement (along with an RFC 2119 "SHOULD"):

"1.2.1 Prerecorded Video-only: Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content." http://www.w3.org/TR/2008/REC-WCAG20-20081211/#media-equiv-av-only-alt

Straw Poll

This questionnaire was open from 2012-07-11 to 2012-07-26. Results of Questionnaire ISSUE-194: How to provide a mechanism for associating a full transcript with an audio or video element? - Straw Poll for Objections

Now What?