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Re: Question regarding animation requirements in UAAG 1.0

From: David Poehlman <poehlman1@home.com>
Date: Thu, 25 Jan 2001 08:42:12 -0500
Message-ID: <009601c086d4$9ef7c2c0$2cf60141@mtgmry1.md.home.com>
To: "Ian Jacobs" <ij@w3.org>, <clilley@w3.org>
Cc: <w3c-wai-ua@w3.org>
I have a question and a comment:
question: is there an example of a "stylistic effect"?
comment.  With pitch supression as it is done through speech synthesis
today, the audio can be much slower than 80 percent and still be
understood.  I can get my accent to comprehend quite low rates for
instance at 50 percent.  if the voice is pre-recorded and synched then
of course, at low rates much like a recording of any kind, it falls
off the low end of the comprehensibility scale.  A further note.  many
animations are accompanied by synthesized speech such as in ms agent.
The characters move and speak but we currently have no control over
the motion or the audio.

----- Original Message -----
From: "Ian Jacobs" <ij@w3.org>
To: <clilley@w3.org>
Cc: <w3c-wai-ua@w3.org>
Sent: January 24, 2001 2:21 PM
Subject: Question regarding animation requirements in UAAG 1.0


Hi Chris,

In the 16 Jan 2001 draft of the User Agent
Accessibility Guidelines 1.0 [1], there are two checkpoints
that involve control of animations:

 --------
 4.4 Allow the user to slow the presentation rate of audio,
 video and animations. For a visual track, provide at least
 one setting between 40% and 60% of the original speed. For a
 prerecorded audio track including audio-only presentations,
 provide at least one setting between 75% and 80% of the
 original speed. When the user agent allows the user to slow
 the visual track of a synchronized multimedia presentation
 to between 100% and 80% of its original speed, synchronize
 the visual and audio tracks. Below 80%, the user agent is
 not required to render the audio track. The user agent is
 not required to satisfy this checkpoint for audio, video and
 animations whose recognized role is to create a purely
 stylistic effect. [Priority 1]

 4.5 Allow the user to stop, pause, resume, fast advance, and
 fast reverse audio, video, and animations that last three or
 more seconds at their default playback rate.  The user agent
 is not required to satisfy this checkpoint for audio, video
 and animations whose recognized role is to create a purely
 stylistic effect. [Priority 1]
 --------

We are currently discussing whether these requirements
should apply to any type of animation (does that make sense?)
or format used to create animation (markup, script, image format,
style sheet). Note: We have a general "exemption"
clause in our document (for the purposes of conformance) that
says that if the format doesn't enable the UA to recognize or
control the animation effect, then the requirements don't apply.

So my questions are:

1) Do you think that there are any classes of animation or
   animation formats for which these requirements don't make
   sense?

2) Do you have a good definition of "animation" handy?

Thanks for any input,

 - Ian

[1] http://www.w3.org/WAI/UA/WD-UAAG10-20010116

--
Ian Jacobs (jacobs@w3.org)   http://www.w3.org/People/Jacobs
Tel:                         +1 831 457-2842
Cell:                        +1 917 450-8783
Received on Thursday, 25 January 2001 08:42:14 UTC

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