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Screen readers and GIS maps

From: Jesper Tverskov <jesper.tverskov@mail.tele.dk>
Date: Thu, 10 Jun 2004 09:20:19 +0200
To: <w3c-wai-ig@w3.org>
Message-ID: <000001c44ebb$62cd9e70$440bc650@tversdatg7y7vv>

David Woolley wrote:
Maps don't work with screen readers either, particularly UK maps which
are bitmapped.  The question was specifically about (geographical) maps.
You have to solve the problem of presenting maps, within commercial,
particularly intellectual property, constraints, before you need to
worry about pointing within them.

- - - - - - - - - -

I consider the above quote to be mostly wrong.

Nobody expects that a painting of Van Gogh should have an alt-text
conveying exactly the same "artistic" feeling a sighted viewer can get
from looking at such a painting. A short alt-text is enough and
sometimes a longer description but this would still be a far cry from a
true equivalent.
Nobody expects that a symphony, Beethoven no 9, must not be played
without a long description conveying exactly the same feeling to the
deaf. A short description will do in most cases.

Nobody expects that GIS maps most not be used without whole books
attached to them painstakingly spelling out all the details in the map
in plain text.

But the blind should be able to use GIS maps presented on the net just
the same.

I blind person can search for something in the map, find it, and it says
so in the screen reader. The blind can then link to the map from own web
site, email the map to a friend, etc., show it to a child, etc.

The blind can print the map and take it with her on a walk and show it
to somebody when asking for directions like anybody else.

The blind can search for two addresses in the map and then listen to a
route description in the screen reader, etc. We have already GPS systems
giving such directions to drivers, and similar systems are already made
for walkers.
The blind has the same right to be able to use maps on the net as
anybody else, but can of cause not get all the benefits of a user also
able to see the map.

My study shows that even though most GIS maps can only be navigated
using a mouse, most of the map solutions are actually very close to
being accessible also with the keyboard.

An example is MSN. It is still too difficult to see the active link (use
inverted colors), etc., the frame of the map should not be used for
panning, the arrows are too far apart. Four small arrows with the main
directions, as seen in many other maps are enough, etc. But it is
possible to navigate the maps of MSN with the keyboard already today.

The only exception is recentering the map, but such a feature is not
that important in most cases. With the keyboard we can only pan the map
in big steps. But such a feature is easy to make, we just need to make
it possible to pan a map also let us say in steps of 100 yards or
meters. We don't need to be able to recenter ordinary GIS maps pixel for
pixel with the keyboard. It is not useful, nobody cares.

With a few more improvements like better window titles, proper use of
alt-text, etc., GIS maps could also be used by blind people in the above

Jesper Tverskov
Received on Thursday, 10 June 2004 03:20:20 UTC

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