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(X)HTML Techniques (Techniques XML Submission Form)

From: nobody <nobody@web4.w3.org>
Date: Fri, 25 Jun 2004 13:30:45 +0000 (GMT)
To: public-wcag2-techs@w3.org
Message-Id: <20040625133045.94DB913AE3@web4.w3.org>

 checkbox checked

Submission Results:

Technology: (X)HTML Techniques 
Techniques Category: Uncategorized techniques 
Submitter's Name: Chris Ridpath 
Submitter's Email: chris.ridpath@utoronto.ca

<technique id="UNKNOWN">
<short-name>Contrast between text and background</short-name>
 <checkpoint idref="text-equiv" />
 <success-criterion idref="UNKNOWN" />

<p>Color attributes of BODY text has good contrast with the background color.</p>

If there are color attributes in the BODY element they must provide good color contrast between the text and background.

The algorithm used to measure the brightness of the colors is:

((Red value X 299) + (Green value X 587) + (Blue value X 114)) / 1000

The attributes in the BODY element used for text are 'text', 'link', 'vlink' and 'alink'. The attribute used to describe the background color is 'bgcolor'.

If one or more colors are specified in the BODY element then all colors must be specified. If no colors are specified for background and color then this technique does not apply.

The difference between the text (all text attributes) and background (bgcolor) must be a value of 200 or greater as calculated by the algorithm above.


 <affects group="UNKNOWN" />








Additional Notes:

I have reservations about our algorithm but poor color contrast is a problem identified by all user groups and must be addressed.
Received on Friday, 25 June 2004 09:30:46 UTC

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