SIA-R35<video> element visual-only content has accessible alternative

Accessibility requirements

This rule tests conformance of the following accessibility requirements:

Description

This rule checks that <video> elements without audio have an alternative available.

Applicability

This rule applies to every prerecorded <video> element visible, where the video doesn't contain audio.

Expectations

  1. For each test target, the outcome of at least one of the following rules is passed:

Assumptions

  • This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the poster.
  • This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.

Accessibility support

Currently the description track is not supported by most assistive technologies. Video players may be able to work around the lack of support for the description track by using aria-live but few do this today

Examples

Acknowledgments

This document includes material copied from or derived from https://act-rules.github.io/rules/c3232f/. Copyright © 2021 W3C® (MIT, ERCIM, Keio, Beihang).