UAAG2: Clarifying obscuration (SC 1.1.4.)

On Thursday's call today I took an action to update  1.1.4 so that it wouldn't contradict the new definition of "obscure" that we agreed on the call:
- Obscure: To render a visual element in the same screen space as a second visual element in a way that prevents the second visual element from being visually perceived. Note: While the use of transparent backgrounds for the overlaying visual element (e.g., video captions) is an acceptable technique for reducing obscuration, if space is available it is more effective not to overlap visual elements that are both of interest to the user.

BTW: I also looked up where "obscure" came from in UAAG 1.0 and it actually had to do with video obscuring captions, not captions obscuring video (http://www.w3.org/TR/WAI-USERAGENT/guidelines.html#tech-configure-captions).

ALSO I realize that the two bullets in 1.1.6 need handles:

Here are my proposals:

PROPOSAL 1: 

1.1.4 Display of Alternative Content for Time-Based Media: For recognized on-screen alternative content for time-based media (e.g.
captions, sign language video), the following are all true: (Level AA)
(a) Text configurable: The user can configure recognized text within alternative content for time-based media (e.g. captions) in conformance with 1.4.1,
(b) Alternatives not obscured: Alternative content for time-based media is not obscured by the primary time-based media, 
     [ed. Maybe obvious, but added for completeness - transparency is not an option]
(c) Controls not obscured: Alternative content for time-based media do not obscure recognized controls for the primary time-based media, and
     [ed. transparency is not an option]
(d) Primary media not fully obscured: Alternative content for time-based media do not fully obscure the primary time-based media.
     [ed. This is where transparency is allowed...then 1.1.6 requires a non-overlapping option]

PROPOSAL 2 : Add handles  (marked with CAPS and @)

1.1.6 Size and Position of Time-Based Media Alternatives: The user can configure recognized alternative content for time-based media (e.g. captions, sign language video) as follows: (Level AAA)
-@RESIZE: The user can resize alternative content for time-based media up to the size of the user agent's viewport.
-@REPOSITION: The user can reposition alternative content for time-based media to at least two of the following: above, below, to the right, to the left,
and overlapping the primary time-based media.
 - Note 1: Depending on the screen area available, the display of the primary time-based media may need to be reduced in size or hidden to meet this requirement.
- Note 2: Implementation may involve displaying alternative content for time-based media in a separate viewport, but this is not required.


----
CURRENT WORDINGS (from http://lists.w3.org/Archives/Public/w3c-wai-ua/2013JulSep/0018.html):

1.1.4 Display of Alternative Content for Time-Based Media: For recognized on-screen alternative content for time-based media (e.g.
captions, sign language video), the following are all true: (Level AA)
- Don't obscure controls: Displaying time-based media alternatives doesn't obscure recognized controls for the primary time-based media; and
- Don't obscure primary media: The user can specify that displaying time-based media alternatives doesn't obscure the primary time-based media; and
- Use configurable text: The user can configure recognized text within time-based media alternatives (e.g. captions) in conformance with 1.4.1.
Note: Depending on the screen area available, the display of the primary time-based media may need to be reduced in size to meet this requirement.

1.1.6 Size and Position of Time-Based Media Alternatives: The user can configure recognized alternative content for time-based media (e.g. captions, sign language video) as follows: (Level AAA)
- The user can resize alternative content for time-based media up to the size of the user agent's viewport.
- The user can reposition alternative content for time-based media to at least two of the following: above, below, to the right, to the left,
and overlapping the primary time-based media.
 - Note 1: Depending on the screen area available, the display of the primary time-based media may need to be reduced in size or hidden to meet this requirement.
- Note 2: Implementation may involve displaying alternative content for time-based media in a separate viewport, but this is not required.



Cheers,
Jan


(MR) JAN RICHARDS
PROJECT MANAGER
INCLUSIVE DESIGN RESEARCH CENTRE (IDRC)
OCAD UNIVERSITY

T 416 977 6000 x3957
F 416 977 9844
E jrichards@ocadu.ca

Received on Friday, 2 August 2013 19:56:36 UTC