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Re: guideline 7.1 about screen flickering (fwd)

From: Anne Pemberton <apembert@erols.com>
Date: Wed, 25 Jul 2001 07:41:06 -0400
Message-Id: <>
To: Adam Victor Reed <areed2@calstatela.edu>, Charles McCathieNevile <charles@w3.org>, w3c-wai-gl@w3.org

         I hesitate to tell you, but compared to the many children I've 
worked with that had ADD, your attention deficit is worse than most rather 
than milder. (I am thinking back over former discussions including your 
difficulty with taking a phone call while trying to buy a computer). If 
animation on the screen is as distracting to mildly ADD folks, then I would 
expect to see a sizeable number of my students who would be unable to use 
the computers in the lab. Instead, the lab is where these kids are least 
likely to show their deficits. The principal has considered the use of the 
lab as a place for some of these kids to rest from the classroom for a bit. 
If the animation in games and on the web were as distracting to ADD/ADHD 
kids as you suggest, the idea wouldn't have come up.

         When I hit the stop button in IE, the animation stopped. The user 
has control. If a user is a severely distractable as you say, such that 
they cannot remember to use the stop or back button, they should always 
browse with images turned off anyway. The user has control.

         In my opinion, there is sufficient user control over animated gifs 
on a page so they can be used as desirable, on a page that otherwise meets 
accessibility needs.

         One suggestion --- the alt tag for an animated gif should mention 
the motion so that distractable people can choose not to see it, if they 
are browsing without images and are too distractable to chance encountering 
an animation on an unknown page. For example, the simple alt tag for the 
logo in question would be: "Animated Department Logo".  Remember that 
having the images there, animated or not, is critical to the text-impaired 
folks. The animation helps make the logo more memorable to the user, IMHO ...


At 07:36 AM 7/25/01 -0700, Adam Victor Reed wrote:
>My attention deficit is milder than most - and the flash is
>distracting enough to prevent me from being able to use ANY
>information on that page. Being unable to turn the flashing off
>manually is bad bad bad; even if one could, some people with AD
>will be too distracted to click on the correct icon within a
>reasonable time. My interpretation of "until user agents" is
>"until user agents themselves", i.e., after appropriate
>customization, the user agent will do it without requiring manual
>intervention by the user - who, in the case of a user with AD,
>may be unable to attend to it when flashing is already
>distracting him.
>If there is a mandate to deliver this animation, it should be
>converted to a technology that automatic de-animation in existing
>browsers is already equipped to handle, e.g. a multiframe GIF with
>a *.gif file name and an image/gif content type.
>                                 Adam Reed
>                                 areed2@calstatela.edu
>Context matters. Seldom does *anything* have only one cause.
>On Tue, Jul 24, 2001 at 02:37:35PM -0400, Charles McCathieNevile wrote:
> > I don't think that this image is OK, unless the group feels that the "until
> > user agents" part of the checkpoint means it is no onger applicable. It 
> moves
> > at something between 5 and 25 Hz in my viewer, and may preset problems with
> > concentration or photosensitive epilepsy.
> >
> > I think that most browsers now allow people to stop the animation, but I do
> > not think I am in a position to decide that for the group. Could we please
> > add it to the agenda as a matter of some urgency.
> >
> > Cheers
> >
> > Charles McCN
> >
> > --
> > Charles McCathieNevile    http://www.w3.org/People/Charles  phone: +61 
> 409 134 136
> > W3C Web Accessibility Initiative     http://www.w3.org/WAI    fax: +1 
> 617 258 5999
> > Location: 21 Mitchell street FOOTSCRAY Vic 3011, Australia
> > (or W3C INRIA, Route des Lucioles, BP 93, 06902 Sophia Antipolis Cedex, 
> France)
> >
> > ---------- Forwarded message ----------
> > Date: Tue, 24 Jul 2001 11:33:13 -0400
> > From: "Fitzgerald, Jimmie" <Jimmie.Fitzgerald@jbosc.ksc.nasa.gov>
> > To: 'Terrie King' <tking@ucp.org>, w3c-wai-ig@w3.org
> > Subject: RE: guideline 7.1 about screen flickering
> > Resent-Date: Tue, 24 Jul 2001 11:37:35 -0400 (EDT)
> > Resent-From: w3c-wai-ig@w3.org
> >
> > Looks fine to me.  It isn't flickering at all.  What 'they' call screen
> > flicker is more in the lines of image changeouts and color changing.  They
> > really need to change their wording to 'element flicker' or something.  By
> > calling it screen flicker, I think monitor refresh rates.  And that is
> > something we as developers cannot control.
> >
> > Your .gif is good to go.
> >
> > Jim Fitzgerald
> >
> > -----Original Message-----
> > From: Terrie King [mailto:tking@ucp.org]
> > Sent: Tuesday, July 24, 2001 10:45 AM
> > To: w3c-wai-ig@w3.org
> > Subject: guideline 7.1 about screen flickering
> >
> >
> > Okay, experts!  I have been asked to put another agency's animated gif 
> on my
> > Web site.  I am hesitant to  use it because of guideline 7.1--"Until user
> > agents allow users to control flickering, avoid causing the screen to
> > flicker."  Here's the link to the checklist item:
> > http://www.w3.org/TR/WCAG10/wai-pageauth.html#tech-avoid-flicker
> >
> > How can I determine if the gif in question is within the guidelines?  (gif
> > attached)  If it is not, I guess I can ask for a non-animated gif.
> >
> > Terrie
> >
> > ---------------------------------------------
> > Terrie L. King
> > Internet Marketing Manager
> >
> > UCP National
> > 1660 L Street, NW, Suite 700
> > Washington, DC  20036
> > Ph: 800-872-5827
> > Fax: 202-776-0414
> > Web site:  http://www.ucp.org

Anne Pemberton

Received on Thursday, 26 July 2001 07:45:38 UTC

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