Re: guideline 7.1 about screen flickering

Curious to see what these would look like, I made a demo that uses these
images.  You can see flickering images (in macromedia Flash) at 4, 7, 20,
and 59 Hz at http://ncam.wgbh.org/richmedia/flicker_demo_start.html.  The
effect of all four together is awful, so I put a link next to each to see it
by itself.  That only makes it worse.  Having made these and looked at them
quite a bit today, I wholeheartedly support the WCAG and 508 screen flicker
guidelines.

I assume that these qualify as a violation of the rules...or does the whole
screen need to flicker?

http://ncam.wgbh.org/richmedia/flicker_demo_start.html

Andrew

On 7/24/01 10:44 AM,  Terrie King (tking@ucp.org) wrote:

> 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
> 
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Received on Thursday, 26 July 2001 16:24:25 UTC