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RE: UAAG 2.0 guidelines for video AND AUDIO

From: Jim Allan <jimallan@tsbvi.edu>
Date: Tue, 4 May 2010 14:16:24 -0500
To: "'Jim Allan'" <jimallan@tsbvi.edu>, "'HTML Accessibility Task Force'" <public-html-a11y@w3.org>
Cc: "'WAI-UA list'" <w3c-wai-ua@w3.org>, "'John Foliot'" <jfoliot@stanford.edu>
Message-ID: <0cdd01caebbe$49d04520$dd70cf60$@edu>
Just a slight title change to better reflect the scope. 
And a shout out to Mark Hakkinen for collaborating on this document.

> -----Original Message-----
> From: Jim Allan [mailto:jimallan@tsbvi.edu]
> Sent: Tuesday, May 04, 2010 1:51 PM
> To: 'HTML Accessibility Task Force'
> Cc: 'WAI-UA list'; 'John Foliot'
> Subject: UAAG 2.0 guidelines for video
> 
> The UAAG Guidelines[1] in their present form are organized by basic
> principles that, when applied as a whole, provide guidance in ensuring
> that a user agent and the (accessible) content it renders, and provides
> interaction with, is accessible.  As such, specific guidelines that
> apply to multimedia, or as we call it, time-based media, rendering and
> interaction are found across several of the principles.  This document
> is a first pass at extracting the guidelines of relevance to the media
> accessibility subgroup.  Feedback on these guidelines, as well as the
> overall UAAG document is welcome. The UAAG Implementation document [2]
> is also available for review.
> 
> 
> PRINCIPLE 2. Facilitate programmatic access
> 
> 2.1.1 Platform Accessibility Architecture: Support an platform
> accessibility architecture relevant to the operating environment.
> (Level A)
> 
> 2.1.2 Name, Role, State, Value, Description: 2.1.2 Name, Role, State,
> Value, Description: For all user interface components including the
> user interface, rendered content, and alternative content, make
> available the name, role, state, value, and description via an platform
> accessibility architecture. (Level A)
> 
> 2.1.3 Accessible Alternative: If a feature is not supported by the
> accessibility architecture(s), provide an equivalent feature that does
> support the accessibility architecture(s). Document the equivalent
> feature in the conformance claim. (Level A)
> 
> 2.1.4 Programmatic Availability of DOMs: If the user agent implements
> one or more DOMs, they must be made programmatically available to
> assistive technologies. (Level A)
> 
> 2.1.5 Write Access: If the user can modify the state or value of a
> piece of content through the user interface (e.g., by checking a box or
> editing a text area), the same degree of write access is available
> programmatically. (Level A)
> 
> 2.1.6 Properties: If any of the following properties are supported by
> the accessibility platform architecture, make the properties available
> to the accessibility platform architecture: (Level A)
> 
> (a) the bounding dimensions and coordinates of rendered graphical
> objects
> (b) font family of text
> (c) font size of text
> (d) foreground color of text
> (e) background color of text.
> (f) change state/value notifications
> 
> 2.1.7 Timely Communication: For APIs (for non-web-based user agents)
> implemented to satisfy the requirements of this document, ensure that
> programmatic exchanges proceed at a rate such that users do not
> perceive a delay. (Level A).
> 
> PRINCIPLE 3: Perceivable - The user interface and rendered content must
> be presented to users in ways they can perceive
> 
> 3.1.1 Identify Presence of Alternative Content The user has the ability
> to have indicators rendered along with rendered elements that have
> alternative content (e.g. visual icons rendered in proximity of content
> which has short text alternatives, long descriptions, or captions). In
> cases where the alternative content has different dimensions than the
> original content, the user has the option to specify how the
> layout/reflow of the document should be handled. (Level A).
> 
> 3.1.2 Configurable Default Rendering: The user has a global option to
> specify which types of alternative content by default and, in cases
> where the alternative content has different dimensions than the
> original content, how the layout/reflow of the document should be
> handled. (Level A)
> 
> 3.1.3 Browse and Render: The user can browse the alternatives, switch
> between them, and render them according to the following (Level A):
> 
>    1. synchronized alternatives for time-based media (e.g., captions,
> audio descriptions, sign language) can be rendered at the same time as
> their associated audio tracks and visual tracks, and
>    2. non-synchronized alternatives (e.g., short text alternatives,
> long descriptions) can be rendered as replacements for the original
> rendered content.
> 
> 3.1.4 Rendering Alternative (Enhanced): Provide the user with the
> global option to configure a cascade of types of alternatives to render
> by default, in case a preferred type is unavailable. If the alternative
> content has a different height or width, then the user agent will
> reflow the viewport. (Level AA)
> 
> 3.6.1 Configure Text:  The user can globally set the following
> characteristics of visually rendered text content, overriding any
> specified by the author  or user agent defaults (Level A):
> 
>     * (a) text scale (i.e., the general size of text) ,
>     * (b) font family, and
>     * (c) text color (i.e., foreground and background).
> 
> PRINCIPLE 4. Ensure that the user interface is operable
> 
> 4.1.1 Keyboard Operation: All functionality can be operated via the
> keyboard using sequential or direct keyboard commands that do not
> require specific timings for individual keystrokes, except where the
> underlying function requires input that depends on the path of the
> user's movement and not just the endpoints (e.g., free hand drawing).
> This does not forbid and should not discourage providing mouse input or
> other input methods in addition to keyboard operation. (Level A)
> 
> 4.9.2 Time-Based Media Load-Only: The user has the option to load time-
> based media content @@DEFINE@@ such that the first frame is displayed
> (if video), but the content is not played until explicit user request.
> (Level A)
> 
> 4.9.5 Playback Rate Adjustment for Prerecorded Content: The user can
> adjust the playback rate of prerecorded time-based media content, such
> that all of the following are true (Level A):
> 
>     * The user can adjust the playback rate of the time-based media
> tracks to between 50% and 250% of real time.
>     * Speech whose playback rate has been adjusted by the user
> maintains pitch in order to limit degradation of the speech quality.
>     * Audio and video tracks remain synchronized across this required
> range of playback rates.
>     * The user agent provides a function that resets the playback rate
> to normal (100%).
> 
> 4.9.6 Stop/Pause/Resume Multimedia: The user can stop, pause, and
> resume rendered audio and animation content (including video and
> animated images) that last three or more seconds at their default
> playback rate. (Level A)
> 
> 4.9.6 Navigate Multimedia: The user can navigate along the timebase
> using a continuous scale, and by relative time units within rendered
> audio and animations (including video and animated images) that last
> three or more seconds at their default playback rate. (Level A)
> 
> 4.9.7 Semantic Navigation of Time-Based Media. The user can navigate by
> semantic structure within the time-based media, such as by chapters or
> scenes, if present in the media (AA).
> 
> 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.
> 
> 
> 
> 4.9.9 Sizing Playback Viewport: User has the ability to adjust the size
> of the time-based media up to the full height or width of the
> containing viewport, with the ability to preserve aspect ratio and to
> adjust the size of the playback viewport to avoid cropping, within the
> scaling limitations imposed by the media itself. (Level AA)
> 
> 4.9.10 Scale and position alternative media tracks. User has ability to
> scale and position alternative media tracks independent of base video.
> (Level AAA)
> 
> 4.9.11 Adjust Playback Contrast and Brightness. User has ability to
> control the contrast and brightness of the content within the playback
> viewport.
> 
> 1. http://www.w3.org/WAI/UA/2010/ED-UAAG20-20100430/
> 2. http://www.w3.org/WAI/UA/2010/ED-IMPLEMENTING-UAAG20-20100430/
> 
> 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 Tuesday, 4 May 2010 19:12:52 GMT

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