1.2.7 Extended Audio Description (Prerecorded): Where pauses in foreground audio are insufficient to allowaudio descriptions to convey the sense of the video,extended audio description is provided for allprerecordedvideo content insynchronized media. (Level AAA)
The intent of this Success Criterion is to provide people who are blind or visually impaired access to a synchronized media presentation beyond that which can be provided by standard audio description. This is done by periodically freezing the synchronized media presentation and playing additional audio description. The synchronized media presentation is then resumed.
Because it disrupts viewing for those who do not need the additional description, techniques that allow you to turn the feature on and off are often provided. Alternately, versions with and without the additional description can be provided.
People who are blind, people with low vision who cannot see the screen, as well as those with cognitive limitations who have difficulty interpreting visually what is happening, often use audio description of the visual information. However, if there is too much dialogue the audio description is insufficient. Extended audio description can provide the additional information needed to understand the video.
Example 1. Video of a lecture. A physics professor is giving a lecture. He makes freehand sketches on the whiteboard, speaking rapidly as he draws. As soon as he has finished discussing one problem, he erases the drawing and makes another sketch while continuing to speak and gesture with his other hand. The video is paused between problems, and extended audio description of the professor's drawings and gestures is provided; the video is then resumed.
Resources are for information purposes only, no endorsement implied.
Each numbered item in this section represents a technique or combination of techniques that theWCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, seeUnderstanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.
G8: Providing a movie with extended audio descriptions using one of the following:
Using any player that supports audio and video
Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.
H96: Using the track element to provide audio descriptions (HTML)
Adding extended audio description in multiple languages in SMIL 1.0 (future link)
Adding extended audio description in multiple languages in SMIL 2.0 (future link)
narration added to the soundtrack to describe important visual details that cannot be understood from the main soundtrack alone
Note 1: Audio description ofvideo provides information about actions, characters, scene changes, on-screen text, and other visual content.
Note 2:In standard audio description, narration is added during existing pauses in dialogue. (See alsoextended audio description.)
Note 3:Where all of thevideo information is already provided in existingaudio, no additional audio description is necessary.
Note 4:Also called "video description" and "descriptive narration."
audio description that is added to an audiovisual presentation by pausing thevideo so that there is time to add additional description
Note:This technique is only used when the sense of thevideo would be lost without the additionalaudio description and the pauses between dialogue/narration are too short.
information that is notlive
audio orvideo synchronized with another format for presenting information and/or with time-based interactive components, unless the media is amedia alternative for text that is clearly labeled as such
the technology of moving or sequenced pictures or images
Note:Video can be made up of animated or photographic images, or both.
This Web page is part ofUnderstanding WCAG 2.0: A guide to understanding and implementing WCAG 2.0 (see thelatest version of this document). The entire document is also available as asingle HTML file. See theThe WCAG 2.0 Documents for an explanation of how this document fits in with other Web Content Accessibility Guidelines (WCAG) 2.0 documents. To send public comments, please follow theInstructions for Commenting on WCAG 2.0 Documents.
Copyright © 2023World Wide Web Consortium.W3C®liability,trademark anddocument use rules apply.