The extended audio description needs to be provided for videos that have complex content and the audio provided with the video may not be sufficient to explain the visuals in the video.
Table of Contents
Official Requirements
1.2.7 Extended Audio Description (Prerecorded): Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media. (Level AAA)
Why Extended Audio Description is required?
Audio descriptions help to convey the information in the video to people with vision impairments.
However, in some cases where there are too many dialogues or multiple things happening simultaneously in the video requires additional audio to ensure they don’t miss important content.
For example: In a lecture video, the physics professor is explaining a concept by sketching its schematic representation on the whiteboard. However, when he moves on to the next concept he erases the drawing to make another sketch. In this case, the video needs to provide more information about the professor’s drawings and gestures if any as it is essential to understand the concept.
Also read: Understanding Success Criterion 1.2.3 Audio Description or Media Alternative (Prerecorded)
How do we fix it?
- Provide extended audio description by pausing the video and audio wherever necessary
- Provide context and other relevant aspects of the video that is not conveyed by the character’s dialogue alone.
- Provide an option to turn on and off the external audio description feature or create two versions of the video where one version contains the external audio and other doesn’t
Exceptions
There is no need for audio description if all of the information in the video track is already available in the audio track.
Reference
Understanding Success Criterion 1.2.7: Extended Audio Description (Prerecorded)