object for audio must have alternative

Definition object elements used for audio only must have caption or text transcription of the audio content.
Purpose
  • Captions and text transcripts provide a means for people cannot hear the audio to understand the audio content.
  • Some types of learning disabilities affect speech perception, captions and text transcripts provide an alternative way to understand the audio content.
  • When the language of the audio is different than the native language of the listener, captions and text transcripts support the listner in understanding the audio content.
Required Yes for HTML4 Legacy Techniques ruleset mapping
WCAG 2.0 Success Criteria

1.2.1 Audio-only and Video-only (Prerecorded) (Level A, Primary Success Criterion)

Rule Category Audio/Video
Scope Element
Target Resources object elements
  • object
Techniques
  • Use the audio element instead of the object element for audio only content, since the audio element provides better support for captions and text transcripts.
  • Use aria-describedby attribute to point to a text description of the audio only content.
Manual Checks
  • Check the web page for a link to a text transcript of the audio, or if the transcript is part of the page rendering the audio.
  • Check the media player for a button to turn on and off captions.
  • When captions are enabled on the media player, check to make sure the captions visible and represent the speech and sounds heard on the audio.
  • In some cases "open" captions might be used, this means the captions are alway "on" as part of the video.
Informational Links