Priority 1 Item 16
For any time-based multi-media presentation (e.g., movie
or animation) synchronize equivalent alternatives (e.g., captions
or auditory descriptions of the visual track) with the presentation.
Example of a time-based multimedia
presentation
Users who can't see the visual content of a multimedia presentation
require an auditory description because they can't get close enough
to the display monitor, have poor eyesight or they could be blind.
Users who can't hear the audio track require a text description.
They may be working in a quiet environment, like a library, with the
sound turned down or they might be in a noisy environment where the
sound is obscured by noise. They could have poor hearing or could
be deaf.