Definition Live and prerecorded video with synchronized audio (i.e. a movie, lecture) using the video element must have synchronized captions.
Purpose
  • Synchronized captions provide a means for people who cannot hear the audio content of a video to understand the audio content of the video.
  • Some types of learning disabilities affect auditory processing, captions provide an alternative way to understand the audio content of a video.
  • This rule covers the requirements of both WCAG 2.0 Success Criteria 1.2.2 and 1.2.4, and therefore covers both live and prerecorded video content.
Mappings
  • HTML4 Legacy Techniques (Recommended)
  • HTML5 and ARIA Techniques (Required)
WCAG 2.0 Success Criteria

1.2.2 Captions (Prerecorded) (Level A, Primary Success Criterion)

Rule Category Audio/Video
Scope Element
Target Resources video elements
  • track
  • video
Techniques
  • Use the track element to add a caption track to the video content.
  • Use open captions to include the captions as part of the video.
  • If closed captions are not support, use open captioning to include captions as part of the video.
  • Open captioning is the only way to insure that captions are available on most cells phones and tablet computers connecting through wireless services.
Manual Checks
  • When captions are enabled on the media player, verify the captions are visible.
  • Verify that the captions accurately represent and are synchronized with the speech and sounds in the video.
Informational Links