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Re: Color Contrast (Minimum) Level AA requirement for "Photography" image

From: Chaals McCathie Nevile <chaals@yandex.ru>
Date: Thu, 28 Sep 2017 17:52:41 +0200
To: w3c-wai-ig@w3.org
Message-ID: <op.y69813o1ftbnq3@desktop-kurf4r9.home>
I'm afraid this is absolutely not compliant, and simply increasing the  
resolution will not make it comply. That gets around the issue of text in  
images being difficult to read e.g. when magnified, which is not the  
obvious problem here. Higher resolution has negligible impact on colour  

There are tools you could find that will show what the image looks like  
for a user who needs high contrast - at a miniuim various browsers and  
operating system settings let you test quickly by applying some high  
contrast modes.

There are various techniques you could use to fix the problem. The most  
straightforward one being to change the colours of the text, or of the  
image - making the sea a deeper darker blue and the caption over it a  
brighter white, making the sky a little paler and the text black or dark  
brown, you might well get there.

If the text is presented with the image as a background, you might be able  
to do more - I would suggest that you consider SVG, if your developers  
have the skills, as a way to get closer to what you want.

If you can get it through the people who do the visual design, moving the  
heading above the picture as a real heading - perhaps with a light colour  
bleed from the picture, would both deal with the contrast issue and avoid  
having text in a .jpg.

I think it is nowhere near as good, but you might also consider providing  
an explicit high-contrast mode for your website, which would mean that  
your "main" site doesn't comply but you can provide an accessible version.  
Reasons I prefer to avoid that include the cost of maintenance and  
likelihood that you will miss something as you introduce an accessibility  
or similar feature to one version that needs to be working correctly in  
the other, and because it tends to be a poor PR message to suggest that  
you think people should be treated as "equal but different" when there is  
no obvious necessity to do so.



On Thu, 28 Sep 2017 17:17:21 +0200, Subramanian, Poornima (PCL)  
<psubramanian@hagroup.com> wrote:

> Great, here's my question -
> In our application, there are brochure images which are actually the  
> >"photography of cover page" in JPEG format. Though they are photography  
> images, >it has large amount of text in it which does not meet minimum  
> color contrast >ratio.
> Attached image is a sample brochure.
> I find the below NOTE for the WCAG Reference: 1.4.3 Contrast (Minimum):  
> The >visual presentation of text and images of text has a contrast ratio  
> of at least >4.5:1
> “Note: Images of text do not scale as well as text because they tend to  
> >pixelate. It is also harder to change foreground and background  
> contrast and >color combinations for images of text, which is necessary  
> for some users. >Therefore, we suggest using text
> wherever possible, and when not, consider supplying an image of higher  
> >resolution.”
> Can you please look and advise if the "color contrast” on this image is  
> >required to make this image compliant? Or increasing the resolution of  
> image >alone will be sufficient?
> Your suggestions, please?
Chaals is Charles McCathie Nevile
find more at http://yandex.com
Received on Thursday, 28 September 2017 15:53:15 UTC

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