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Re: Images and alternative text

From: Leif Halvard Silli <lhs@malform.no>
Date: Fri, 16 Jan 2009 21:34:53 +0100
Message-ID: <4970EF6D.9080401@malform.no>
To: chrisreeve15@yahoo.com
CC: public-html@w3.org, bzbarsky@mit.edu

Chris Reeve 2009-01-16 18.15:
> Boris, and Leif, in response to WCAG 1.4.5, is there a rule on
> what is a good/bad "alt" tag for images of text.

It is some times since this thread  (ore even I myself ...) last 
was active ... But supposing you ask how to apply WCAG 1.4.5 [1] 
for the below scenarios ...

> Scenario A:
> 
> A photographer takes a picture, and surroundings have images of
> text in it. But the intent and writeen document only shows the
> integrity of one image (no text is inside it)

I guess you have to look at the photo and make a judgement about 
how important the text bits are, af they are you must somehow 
quote those text bits in the alt text.

> Scenario B:
> 
> A photographer takes a picture, and surroundings have images of
> text in it. This time the intent of the image and the document
> suggests that multiple areas in the image have image of text
> (1.4.5) and the site suggests that multiple areas should be
> used.

You could use the OBJECT element and present the the complete 
"story" of the image as fallback, in a more structured way.

> I also have a text inside a logo and WCAG 2.0 suggests that
> text inside logos should comply with 1.4.5. When 1.0 was out it
> used to be "Company logo"?

What is the problem here? You could use <img src=image alt="ACME 
Corp. The company that makes everything!" >.

I'll add a Scenario C:

An online library of scanned books, where each page contains the 
scanned image of a page, plus the OCR version of its content below 
the scanned image. See for example Project Runeberg [1], which 
uses alt="scanned image" for each scanned image, which seems very 
meaningful to me.

[1] 
http://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-text-presentation.html
[2] http://runeberg.org/display.pl?mode=facsimile&work=scanbrit
-- 
leif halvard silli
Received on Friday, 16 January 2009 20:35:37 UTC

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