Definition embed elements used for prerecorded video with synchronized audio (i.e. a movie, archived lecture) must have audio description of the video content.
Purpose
  • Text and audio descriptions provide a means for people who cannot see the video to understand the video content.
  • Some types of learning disabilities affect visual processing, text and audio descriptions provide an alternative way to understand the video content.
  • This rule covers the requirements of both WCAG 2.0 Success Criteria 1.2.3 and 1.2.5, that is why a text description of the video content cannot be used to satisfy this rule.
Mappings
  • HTML4 Legacy Techniques (Recommended)
  • HTML5 and ARIA Techniques (Required)
WCAG 2.0 Success Criteria

1.2.3 Audio Description or Media Alternative (Prerecorded) (Level A, Primary Success Criterion)

Rule Category Audio/Video
Scope Element
Target Resources embed elements
  • embed
Techniques
  • Use the video element instead of the embed element for video only content, since the video element provides better support for audio description tracks.
  • Include an audio track in the video that describes the video content.
  • Use aria-describedby attribute to point to a text description of the video only content.
Manual Checks
  • When audio descriptions are enabled on the media player, check to make sure the audio description can be heard.
  • If there is a audio description make sure the description accurately describes the video content.
  • If there is a text description make sure the description accurately describes the video content.
Informational Links