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From: Gregg Vanderheiden <GV@TraceCenter.org>
Date: Sun, 15 Feb 1998 23:24:17 -0600
Message-ID: <01BD3AB1.EA4429C0.GV@TraceCenter.org>
To: "'GL - WAI Guidelines WG'" <w3c-wai-gl@w3.org>, "'IG - WAI Interest Group List'" <w3c-wai-ig@w3.org>
I have been trying to look at the different postings on the ALT Text issue 
and dig out the common threads and see if there is a bottom line or simple 
solution.
A few interesting points however, seem to complicate this whole discussion. 
 The answers seem simple if we just forget some of them.  But they are all 
real, and when I try to account for all of them - it is a little tougher. 
  Let me list what I have as a starting point to getting a complete list.



1)  Unlike text browsers, graphic browsers currently leave an image on the
page, even if there is a null alt-text.  Thus, people using graphic screen
readers are still left with the screen reader announcing "image" without
any explanation as to what the image is.  Thus, marking decorative images
with no alt-text or with alt="" are identical.

2)  What some people consider decorative other people consider information.
 More importantly, if alt="" is a legitimate strategy for anything that
does not see important, it's possible that page authors might use it
overmuch, removing much content.

3) Alt-text was originally designed to provide the same function as the
graphic.  When the graphic is a link, the alt-text would generally just
provide text to indicate what the link was (not what the graphic looked
like).  However, when a graphic is not used as a link, then the purpose of
the graphic is usually to present something graphic, and the alt-text would
in that case have to describe the graphic.  This has led to a lot of
confusion.

4) Now we have a "title" whose function I have sometimes seen depicted as
providing additional information about the function and sometimes as
providing additional information about the appearance.  Again, if something
is graphic, its function is its appearance.

5) Finally, we have objects that need alternative text associated with
them, but for which alt-text is not supported.  Thus, "title" takes over
the role.

So it appears to me that we have somewhat of a mess that has three major
characteristics:

a)  Some users who are blind want information about graphics, including
decorative graphics, while other users do not.  Thus, whether to make
graphics invisible has no single right answer.

b) There seems to be much confusion, and not much consensus, about the
exact role for alt-text and title on different objects, and on the same
object used in different ways (e.g., a graphic).

c)  Title appears in places where alt-text does not, making the division of
roles between alt-text and title more complicated.


Right now I'm scratching my head while reading all the messages
going by, and trying to see whether there is a strategy we might use for 
sorting all of
this out.

It obviously needs to be backward-compatible,

and it would be a shame if it turned out we needed to define anything 
differently than we just did in HTML 4.0.  (Like the role of alt text vs 
title or whatever)

However, above all, we have to think of something that is more
straightforward and easy to explain than what we have now.  It's quite
evident that what we have right now is abundantly confusing even to people
who are advocates and well-versed in the area.

Perhaps instead of restating positions and opinions about what things stand
for or have stood for, etc., we should focus on trying to summarize what it
is that we're trying to achieve with the combination of alt-text and title
(and for that matter long-desc), then list the constraints that must be met
by a solution.  Then finally we should try to propose something that is
simple, straightforward, consistent, and provides maximum accessibility
across the different types of objects today and whatever we can predict
about the future.



I think the eventual strategy needs to handle all of the following issues
together in a comprehensive solution strategy:

I-1) The role of alt-text (on images used as anchors, stand-alone images, 
and
anywhere else it's supported);

I-2) The role of title (for same conditions as above, as well as for 
objects
where alt-text is not supported);

I-3) How to handle decorative graphics and spacer graphics;

I-4) Proper use of long-desc (and temporarily D-tags?)



In a separate post, I think we will pull out just the items from this 
message and what we've seen in other messages that fall in the categories 
I've described above, so that we can begin to build a list of requirements, 
concerns, etc., and see if we can get all the issues and constraints down 
in one place, so that we can then work forward to an internally consistent 
and straightforward solution.


I also wonder if we should take this back to the GL list and work on it, 
 then bring it back to the IG  and other lists for discussion.




Gregg




-- ------------------------------
Gregg C Vanderheiden Ph.D.
Professor - Human Factors
Dept of Ind. Engr. - U of Wis.
Director - Trace R & D Center
gv@trace.wisc.edu    http://trace.wisc.edu
FAX 608/262-8848
For a list of our listserves send "lists" to listproc@trace.wisc.edu
Received on Monday, 16 February 1998 09:04:04 GMT

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