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Alt Text Must Be Short

From: Chris Ridpath <chris.ridpath@utoronto.ca>
Date: Fri, 3 Dec 2004 14:02:37 -0500
Message-ID: <049e01c4d96a$a7c76580$e29a968e@WILDDOG>
To: "WAI WCAG List" <w3c-wai-gl@w3.org>

A call to arms in defense of short Alt text.

I find that the current WCAG2 [1] requires Alt text to be short. It Alt text
is not short then it fails a level 1 success criteria for guideline 4.1 [2].
The HTML spec is very clear that Alt text must be short [3]. To quote: "The
alt attribute provides a short description of the image...". It also states
that the Longdesc "should supplement the short description provided using
the alt attribute".

It's level 1.
Alt text must be short

But how long is short? We're striving to remove the ambiguities in the WCAG2
test suite [4] so we must define what short is. Short varies according to
the language of the content. For English content we have picked the
threshold of 100 characters as short. We still need to hear from language
experts to find out what short means in other languages. These language
specific values must be determined for, at least, every language the WCAG2
becomes translated.

"Short" is specific to each language.
Alt text must be short.

What if my Alt text must be greater than the threshold? That's OK. You just
need to confirm that your Alt text is the shortest possible for the image.
The purpose of testing for short Alt text is to improve the quality of Alt
text. We know that poor Alt text is a cause for concern and has been
identified as an accessibility barrier in many studies including the recent
DRC [5] report.

You can exceed the threshold and still be short.
Alt text must me short.

How important is a test for short Alt text? Well actually, it's not all that
important. Most authors already put in short Alt text (if they enter Alt
text) and most accessibility checking programs have tested for it for years.
The proposed test for short Alt text will catch a few authors who are
unaware of the need for short Alt text. It will also catch the authors who
tend to unintentionally ramble in their Alt text. It may also help to catch
programs that automatically put in Alt text. The problem of *missing* Alt
text is far greater than *long* Alt text. In our testing we have seen many
more images with missing Alt text than long Alt text.

It's not the end of the world, but still,
Alt text must be short.

If it's not all that important, why is short Alt text a level 1 requirement?
It's level 1 because the WCAG2 success criteria [2] that requires short Alt
text is level 1. This demonstrates that the real world importance of the
accessibility test may sometimes not quite match up with the more abstract
guidelines. We'll have to work this out. Overall, there appears to be a good
correlation between the tests and the success criteria level.

Wadda we want?
Short Alt text.
When do we want it?

To order your "Alt Text Must Be Short" t-shirts, coffee mugs and key chains
please visit our web site:

Or, If you wish to donate to the Save Short Alt Text relief effort, please
send your tax deductible donation to our web site.

The working group will be taking a poll on the test for short alt text later
next week [7]. If you are concerned about the length of Alt text please be
sure to voice your opinion and enter the poll.

Alt text must be short.

I hope the test will be accepted and we can move on to the more difficult
issues in the test suite.

Say it loud, and say it proud.
Alt text must be short!


[1] http://www.w3.org/WAI/GL/WCAG20/
[2] http://www.w3.org/WAI/GL/WCAG20/#use-spec
[3] http://www.w3.org/TR/html4/struct/objects.html#edef-IMG
[4] http://www.w3.org/WAI/GL/WCAG20/tests/
[5] http://www.drc-gb.org/publicationsandreports/2.pdf
[6] http://www.w3.org/WAI/GL/WCAG20/tests/test3.html
[7] http://www.w3.org/2002/09/wbs/35422/testsuite1/
Received on Friday, 3 December 2004 19:03:08 UTC

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