action-460 rewrite 4.9.8

ACTION-460
jallan to discuss EVD2 & 3 - add to IER to 4.9 SC or create new SC,
also review CC2,3,4

Proposal:
add ED information to 4.9.8 track manipulation - Intent/Example/Resources
add to IER, use case - author created the ED as a separate track, then
user can select the ED track.

4.9.8 Track Enable/Disable of Time-Based Media: During time-based
media playback, the user can determine which tracks are available and
select or deselect tracks. These selections may override global
default settings for captions, audio descriptions, etc.

Intent:
Authors are able to create time-based media with video (perhaps
multiple video tracks), multiple audio tracks ( e.g. different
languages, video description, extended video description), and
multiple caption tracks (e.g. different languages, text of video
description, text of extended video description). Users should be able
to identify and select from the available tracks. The user may also
change their selections. The user agent must provide a mechanism to
list the available author supplied tracks and allow the user to select
which to play.

Examples:
Jose, a student with a hearing disability, sometimes misses parts of
the dialog in movies because of the sound level or background noise.
He can select the caption track to be displayed so that he can read the dialog.

Lin, who is blind, cannot see all of the action in suspense movies.
She can select the video description track in addition to the audio
track, to hear the action and scenes described during the movie and
not miss out on the suspense.

Mary has a learning and attention problem. She needs
  more elaborate descriptions of what is happening in a movie of a
  science demonstration. Mary selects the author-supplied extended
  description audio track for which the video pauses for extended
  descriptions of specific concepts. Mary also selects the
  author-supplied extended description caption track to go along with
  the extended description audio track so that she can read along with the
  audio and focus on reading and listening to the content.

Resources:
HTML 5 Video Element http://www.w3.org/TR/html5/video.html#video

-- 
Jim Allan, Accessibility Coordinator & Webmaster

Texas School for the Blind and Visually Impaired

1100 W. 45th St., Austin, Texas 78756

voice 512.206.9315    fax: 512.206.9264  http://www.tsbvi.edu/

"We shape our tools and thereafter our tools shape us." McLuhan, 1964

Received on Thursday, 4 November 2010 17:04:00 UTC