SIA-R25<video> element visual content has audio description

Accessibility requirements

This rule is not required for conformance to any accessibility requirements.


This rule checks that prerecorded <video> elements have all visual information also contained in the audio.


This rule applies to every prerecorded <video> element that is visible where the video contains audio.


  1. The visual information of each test target is available through its audio, or through an audio description track.


  • 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

There are only a few implementations of video players (without third party technologies) that support audio description tracks at the time of writing.



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