W3C home > Mailing lists > Public > w3c-wai-gl@w3.org > October to December 2003

RE: HTML techniques - Alt-texts for images (no blocker?)

From: John M Slatin <john_slatin@austin.utexas.edu>
Date: Mon, 3 Nov 2003 11:41:35 -0600
Message-ID: <C46A1118E0262B47BD5C202DA2490D1A1DFB9E@MAIL02.austin.utexas.edu>
To: "Yvette P. Hoitink" <y.p.hoitink@heritas.nl>, <w3c-wai-gl@w3.org>

For what it's worth, the How-tos and Demos section of the Accessibility
Institute site  provides several examples for writing alt text in
different situations, including the null alt for spacers, decorative
images, etc.  See
http://www.utexas.edu/research/accessibility/resource/how_to/

John


"Good design is accessible design." 
Please note our new name and URL!
John Slatin, Ph.D.
Director, Accessibility Institute
University of Texas at Austin
FAC 248C
1 University Station G9600
Austin, TX 78712
ph 512-495-4288, f 512-495-4524
email jslatin@mail.utexas.edu
web http://www.utexas.edu/research/accessibility/


 



-----Original Message-----
From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On
Behalf Of Yvette P. Hoitink
Sent: Friday, October 31, 2003 9:59 am
To: w3c-wai-gl@w3.org
Subject: HTML techniques - Alt-texts for images (no blocker?)



In the HTML techniques document, there is a technique called "Short text
equivalents for img elements ("alt-text")":
<http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-HTML-TECHS-20031020.html#img-
alt>

What seems to be missing here, is the explanation of when to use null
alt-text. I remember visiting a website, built by a company who just got
interested in accessibility. They used a lot of spacer images to enforce
layout, each of which had an alt-text saying "Image used for
presentational purposes only". Can you imagine how crazy that drove
their blind visitors? This is a textbook case of when to use null
alt-text. 

Another example of when to use null alt-text is when the alternative
text is already present in the page, for example if have a gallery of
pictures where the title of the image is printed below it. Another
example is the combined use of an icon and text as a link, which is
discussed elsewhere on the page:
<http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-HTML-TECHS-20031020.html#imag
etex
tlinks>.

Besides the lack of explanation about when to use null alt-text, I think
we need some more techniques for providing text equivalents. The WCAG
guidelines version 2 are worded such, that these last two examples I
gave count as providing a text equivalent for non-text content that can
be expressed into words. However, in the techniques document, the
ALT-attribute is the only technique that is presented to provide a text
equivalent for an image.  Reading the techniques document, I would think
that I still had to provide an alt-text for an image, even if (the same)
text was already used as a 'caption' for the image on the page. 
I think this is unfortunate and narrows the intentions of the WCAG 2
document.

Yvette Hoitink
CEO Heritas, Enschede, The Netherlands
Received on Monday, 3 November 2003 12:41:50 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:47:26 GMT