From: John Gardner
Sent: Friday, June 19, 1998 2:01 PM
To: phil@physics.orst.edu; corinne@physics.orst.edu; rubin@physics.orst.edu; tatej@ucs.orst.edu; allenlw@physics.orst.edu; robby@MATH.ORST.EDU
Cc: dorboloj@ucs.orst.edu; woodss@ccmail.orst.edu; tracy.bentley@orst.edu; ron.stewart@orst.edu; curt.pederson@orst.edu
Subject: Accessible web graphics
In the last few days we've made a major breakthrough in bandaid
accessibility that should permit people to make most web course materials
fully accessible to people who are blind or dyslexic. This is not the
ultimate solution, but it is something that is not incredibly difficult and
will work NOW. We're still some distance from accessibility of
time-dependent and interactive graphics, but we can certainly make bit-maps
accessible today.
If the author uses good HTML or XML code, the real problems right now are
the graphics - math and other things. Some of these pictures can be
described adequately by ALT tags, but only the very simplest ones.
Volodya Bulatov has been experimenting with a way to add labels and other
information to existing bit-maps, and we tried his experiments out
yesterday. They work!
I had to upgrade my screen reader to work with IE 4.0, and Volodya assured
me that it works with Netscape as well, although I haven't yet tried it.
My opinion is that if it works with anything, that's good enough, because a
blind or severely dyslexic student will just use whichever browser provides
best access.
The author (or more likely a minimum-wage student who is familiar with that
course material) must add a link to the original HTML/XML file that points
to a Java script that creates two frames, one of which contains the image
and one of which displays a label associated with whichever object the
mouse is on in the figure. When the mouse is moved from one object to
another the label changes, and the screenreader automatically speaks that
frame. So one can just move the mouse around (a blind student would be
moving her finger around on a tactile figure mounted on a cheap touch
screen pad or digitizing pad) and hear the label of each object. If an
additional link is associated with that object to present more information,
the label would say something like "click for more info", and a new window
will pop up when clicked that can be browsed with a screen reader. You
should realize that clever authors could use this for more than just making
information available to people with print disabilities. One could include
an entire lecture inside objects in a picture.
Creating the label file is fairly straightforward, and Volodya will make an
authoring tool to make it as simple as possible. An object will be
identified by the position of an arbitrarily-shaped polygon, the label
defined, and if desired a link to more info given. One needs only to
create object polygons in the right order if any overlap.
Now to math. For existing files, simple equations can just be written in
ALT tags. We can use this frame solution to give, for example, a LaTeX
equation for a complex equation that a dedicated student can read. I would
like to do a quick market survey to find out how best to do this before we
actually begin making such files.
But what about on-line math? I know that these are represented by graphic
images in some cases (ALT tags should work here for most), but I also know
that there are symbol fonts that can represent many things that appear on
line. Things like greek characters, integral signs, etc. How in fact are
these represented in the HTML files that people normally use? How does the
MS Word HTML converter code a Greek letter that is put in as just a font
and not a math character for example? What about other authoring methods?
If you could point me to a few sites where this kind of math appears on the
web I would like to see whether my screen reader can read them. Funny that
a physicist has avoided reading these sites previously! I am just not sure
how the screen reader handles special fonts.
I would like to understand how best to handle existing math on the web
within the next few days. I am attending the President's Council next
Thursday and might be able to present a case for some funding for turning
your web sites into fully accessible documents if you are willing to
cooperate. This could put OSU squarely into the forefront of electronic
and distance ed accessibility and open up all kinds of possibilities for
both attracting students with print disabilities and getting Foundation and
NSF funding. Of course this method is hardly restricted to math and
science. It can be used to make maps accessible, all kinds of flow charts
and diagrams that now appear as bit maps, etc.
With today's technology, a blind student reading these materials will need
tactile figures. These could be printed by the student if she has a TIGER
printer. Right now, the SSD office would probably just have to make up a
tactile copy. However by comparison to efforts now necessary, this is
trivial. The picture could be printed on a TIGER or printed on swell paper
that is then run through the toaster that causes the black parts to swell,
and then it's done. No braille coding or image manipulation to make it
"accessible".
Much thanks.
John