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RE: UAAG 2.0 guidelines for video AND AUDIO

From: Jim Allan <jimallan@tsbvi.edu>
Date: Wed, 19 May 2010 11:21:36 -0500
To: "'Janina Sajka'" <janina@rednote.net>
Cc: "'HTML Accessibility Task Force'" <public-html-a11y@w3.org>, "'WAI-UA list'" <w3c-wai-ua@w3.org>, "'John Foliot'" <jfoliot@stanford.edu>
Message-ID: <076401caf76f$5a94eb60$0fbec220$@edu>
All done. Though there may need to be some editing/positioning to get things
in the 'proper' place. For now, 'proper' is in the document.
Jim

> -----Original Message-----
> From: public-html-a11y-request@w3.org [mailto:public-html-a11y-
> request@w3.org] On Behalf Of Janina Sajka
> Sent: Tuesday, May 18, 2010 6:07 PM
> To: Jim Allan
> Cc: 'HTML Accessibility Task Force'; 'WAI-UA list'; 'John Foliot'
> Subject: Re: UAAG 2.0 guidelines for video AND AUDIO
> 
> Jim, and others;
> 
> These are important requirements. Can you either past them into
> directly, or perhaps by URI reference, into the requirements document
> the HTML-A11y Task Force Media Subteam is using to gather requirements:
> 
> 
> http://www.w3.org/html/wg/wiki/Accessibility_Requirements_of_Media
> 
> 
> Please note that we may move this resource following the Media telecon
> call this Wednesday. It's currently in the HTML-WG Wiki, and probably
> should be in the TF Wiki.
> 
> Also, while I hate to rush anyone, we're trying to close out
> requirements gathering and move to classification (i.e. "must haves for
> HTML 5" vs. "could waith for HTML5++). This, inturn, willtake us to gap
> analysis and decisions about technology recommendations.
> 
> Janina
> 
> Jim Allan writes:
> > 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
> > >
> >
> 
> --
> 
> Janina Sajka,	Phone:	+1.443.300.2200
> 		sip:janina@asterisk.rednote.net
> 
> Chair, Open Accessibility	janina@a11y.org
> Linux Foundation		http://a11y.org
> 
> Chair, Protocols & Formats
> Web Accessibility Initiative	http://www.w3.org/wai/pf
> World Wide Web Consortium (W3C)
Received on Wednesday, 19 May 2010 16:23:17 GMT

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