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Re: Testing color contrast as a screen reader user

for

From: James Nurthen
Date: Mar 18, 2013 4:36PM

If this is just a case of background and foreground colours then it is
automatable, but if any CSS features such as gradients, transparencies and
background images are used then as far as I'm aware it is impossible to
fully automate the check.
As far as I know the best an automated tool can do if these features are
being used is to inform the user that they need to manually check the
contrast in some places.

Regards,
James


On Mon, Mar 18, 2013 at 2:39 PM, Jared Smith < <EMAIL REMOVED> > wrote:

> On Mon, Mar 18, 2013 at 1:25 PM, Birkir R. Gunnarsson wrote:
>
> > I had some issues using wave.webaim.org on a website. It detected 6
> > color contrast errors, but my colleague said they were wrong and not
> > comparing the right things
>
> We'd be happy to look into what the issues are. WAVE uses some pretty
> complex logic to identify *actual* contrast issues - meaning elements
> that have defined colors below the WCAG thresholds that actually
> present text in that combination. This is not easy to automate due to
> CSS inheritance, etc., but I think WAVE does a good job of it. And it
> presents the results in an accessible way.
>
> > Similarly, keyboard focus outline issues. Do the standard
> > accessibility tools detect and report on vissible keyboard focus
> > outlines or not?
>
> We're working on reintroducing this into WAVE. It should soon be
> flagging sites that have links that do not have a visible focus
> outline. Again, it's pretty hard to detect this in an automated way
> because you can't detect focus outlines without actually focusing
> (tabbing to) a link. I'm not aware of any other tool that does this.
>
> Jared
> > > >