rewrite: ACTION-503 - 2.9.2 Time-Based Media Load-Only

2.9.2 Time-Based Media Load-Only: The user can override the play on
load of time-based media content such that the content is not played
until explicit user request. (Level A)

Intent
As an opt-in user setting, autoplay for media is off/paused, until the
user activates 'play'. This prevents media from playing without
explicit request from the user. This also helps users who need to
avoid signals that may trigger seizures, as well as users who are
easily distracted, or who have difficulty interacting with the
controls provided for playing media. The user agent provides a visual
and auditory indicator that the video is in paused state and needs
user interaction to start.

Examples
1. Stuart, a screen reader user, opens a page with an audio element
that starts playing immediately. He cannot hear the screen reader
because of the noise from the audio element, and must search through
the page to find the 'noisy' element to turn it off (or pause). Once
the screen reader is the sole source of audio the he can read the page
and determine if the audio is important and choose to play it.

2. Using similar techniques that are used for pop-up blockers, the
user agent checks to see if the play() request was from user
interaction or a background script. If isn't from direct user
interaction, the user agent could ask the user to explicitly allow the
media to play, perhaps remembering the choice for the site.

3. Playback of a <video> or <audio> element can only be triggered in
response to a user gesture on a touch screen device with no keyboard
(like pop-up blockers).

4. The user agent provides a global control that calls "paused for
user interaction" for all media when a page loads.

Resources
HTML5 4.8.10.8 Playing the media resource
(http://dev.w3.org/html5/spec/Overview.html#playing-the-media-resource)

-- 
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, 17 February 2011 22:38:37 UTC