W3C home > Mailing lists > Public > w3c-wai-gl@w3.org > July to September 2001

RE: Comments on SUFFICIENCY for tomorrows COnf Call

From: Charles McCathieNevile <charles@w3.org>
Date: Sun, 15 Jul 2001 19:03:08 -0400 (EDT)
To: Wendy A Chisholm <wendy@w3.org>
cc: WAI GL <w3c-wai-gl@w3.org>
Message-ID: <Pine.LNX.4.30.0107151829460.5462-100000@tux.w3.org>
I am exploring too, inline:

On Thu, 12 Jul 2001, Wendy A Chisholm wrote:

  The extremes of the argument on this topic seem to be: *ALL* text *MUST*
  have a non-text equivalent versus *SOME* text *SHOULD* have a non-text

CMN There are other angles - I have proposed that particular types of text be
accompanied by illustration, as a checkpoint (what happened to that?), and
there is discussion about how much illustration is required.

  Let's use my W3C people page as an example [1].  It is a very simple page
  with a simple purpose: to give people a brief introduction to me.  I have 3
  images on the page: the W3C logo, the WAI logo, and a photo of myself.  The
  logos give context to the work that I do and my involvement in the W3C. My
  photo helps people identify my age, style, and personality.

  [1] http://www.w3.org/People/wendy/
So you have introduced the basic subject (wendy) and some context - that you
are part of W3C and WAI. In part this is established by using grpahic
language - the layout of the images and the fact that one is clearly
illustrative (a photo) and the others are logos - iconic identification.

  The text on the page describes the work that I do and how I got here. I use
  lots of hypertext links; For each major concept or organization I link to a
  different site.  In some ways, this is a non-text equivalent for the
  text.  From one word, you can find a whole lot more about that word than I
  could in one illustration.

From one blue blob you can try to find something that is illustrated better,
to explain what it is about. Imagine that all the text is greeked. For people
who recognise logos and other image-based link explanations they suddenly
have more comprehension of what you are connecting to. In graphic language,
size is important. If you had a tiny photo of you, and a large Special
Olympics logo, people might have thought that the subject was the special

Not everyone does recognise logos. But I believe that there are trademarks
that are more widely recognised than any other symbol on earth except perhaps
a smile, and I know that companies are prepared to spend millions because
they believe this to be the case.

So logos don't provide acces for everyone, but nor do text equivalents. They
provide access to some people, who otherwise would not have it. Jonathan
Chetwynd has written many times about the value of having graphic identifiers
for sites and ideas, and in many cases there are identifiers - some are more
recognisable than others.

As an example, if I had an image on my site of a red circle with a diagonal
red bar across it, over a large yellow letter M shaped like two arches, I
think almost every sighted person wo saw my page would understand the
political statement implied (how many people can get it just from this text
description?) but if I wrote those ideas in english text then I would reduce
my audience substantially.

  How about this as a compromise:
  *MOST* text *SHOULD* have a non-text equivalent.
  Non-text equivalents include but are not limited to: illustrations, videos,
  audio clips, virtual environment simulations, links to other sites, links
  to illustrations or videos, links to audio clips, etc.  also, metadata
  could be used to define relationships between text and non-text.

CMN I think this is way to vague to be useful as a checkpoint. I think we
should define what kind of text, and what kind of equivalents we are talking
about. More discussion below..

  This is a similar approach to William's "earcons" - he links to them from
  phrases on a page.

Actually I think the earcons are cool - there are other popel who have used
them too. Again, they are not the full answer (there are plenty of people for
whom they are irrelevant) but they can be really helpful.

  *BUT THEN*...
  How do we define *MOST*?  Here are some questions to figure out when it is
  most important to provide non-text equivalents for text:
  Is it P1 to illustrate concrete ideas (i.e. a bridge) but P2 or P3 to
  illustrate abstract ideas (i.e. love)?
  Is it P1 for an education site, but P2 or P3 for john doe's personal site?
  Is it P1 for sites whose main audience is people with cognitive or learning
  disabilities but P2 or P3 for all others?
  Is it P1 to use illustrations for navigation features of a site but not
  abstract ideas?

I think there is a confusion about what WCAG priorities mean here. They are
defined in terms of whether they make content accessible, not how important
it is to make the content of a site or page accessible. It is less important
to me that Jean d'Eau make an accessible homepage, but the requirements are
the same as they are for the goverment of Burkina Faso to make an accessible
home page, if they both choose to do so. And WCAG does not currently define
profiles of target audience as a way of setting priorities (we discussed that
as a scheme for conformance in WCAG 1.0 and it was rejected).

More to the point, I don't think that the difference in priority depends on
the type of the idea (the degree of difficulty probably does), but on the
importance of the idea to the page or message as a whole.

Received on Sunday, 15 July 2001 19:03:08 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 16 January 2018 15:33:38 UTC