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RE: Reworking 1.1

From: John M Slatin <john_slatin@austin.utexas.edu>
Date: Mon, 13 Mar 2006 10:28:21 -0600
Message-ID: <6EED8F7006A883459D4818686BCE3B3B012490CD@MAIL01.austin.utexas.edu>
To: "Gregg Vanderheiden" <gv@trace.wisc.edu>, <w3c-wai-gl@w3.org>
Thanks, Gregg. Very interesting proposal. But it worries me a little.
 
You wrote:
<blockquote>
4)       There is a visual representation of a hurricane showing the
direction of air follow throughout.   Where an obstruction is
encountered the flow
directions distort all around the obstruction.   This is presentation of
information with non-text content - but it is not possible to present
this in
a text alternative.  We have no exception for this.  Only for functional
non-text content.

</blockquote>
 
First: if you're right in saying that it "is not possible" for a text
alternative to present the same information about turbulence as the
visual representation does, then the revised SC you proposed doesn't
require even an *attempt* to describe what's happening in the visual
representation-- the only thing required would be to "identify the
purpose of" the non-text content ("Visual representation of turbulent
flow in a hurricane," for example. That's much weaker than our current
wording, I think, and would be a serious problem for me. (More below.)
 
I have a similar concern about the bullet that includes non-text content
"intended primarily to create a sensory experience": the proposed
wording no longer even hints at the possibility of going beyond a
"descriptive label."  I would like to restore the phrase "at least"
here. The SC could still be satisfied using just a descriptive label,
but it would encourage doing more. 
 
Back to the example about the hurricane:
 
I don't actually agree with the assertion that "it is not possible to
present this [turbulence created when moving air encounters an obstacle]
in
a text alternative." I agree that it is not possible to introduce
hurricane-like turbulence into the text itself (this is one of the
reasons I argued that we should use "text alternative" instead of WCAG
1.0's "text equivalent"). But it is certainly possible to describe in
text what is happening within the visual representation, whether the
representation is static or dynamic. The more I think about it the more
I realize that the visual representation in your example is not a case
of "real" turbulence; it is only a *representation* of turbulence, and
all the text alternative has to do is provide a *textual representation*
of the visual content-- not a representation of the hurricane. It
doesn't have to *be* turbulent any more than the visual representation
has to *be* turbulent.
 
If the visual representation is the output of a simulation, then I agree
that it wouldn't make sense to expect the simulation to output text
rather than dynamically generating a visual representation. But the
visuals produced by the simulation can be described, even if the
description can't be continually updated as the simulation continues to
run.
 
(So now I'm not sure whether I'm arguing against the proposed wording,
or just making the case that this particular example *can* have and thus
would require description rather than mere identification.
 
This is really important. One of my graduate students just sent me
research showing that *one hundred percent (100%)( of scientific
articles published between 1976-2000 included at least one visual
illustration of some sort.
 
John
 
 
 

"Good design is accessible design." 
John Slatin, Ph.D.
Director, Accessibility Institute
University of Texas at Austin
FAC 248C
1 University Station G9600
Austin, TX 78712
ph 512-495-4288, f 512-495-4524
email jslatin@mail.utexas.edu
web http://www.utexas.edu/research/accessibility/
<http://www.utexas.edu/research/accessibility/> 


 

 


________________________________

	From: w3c-wai-gl-request@w3.org
[mailto:w3c-wai-gl-request@w3.org] On Behalf Of Gregg Vanderheiden
	Sent: Monday, March 13, 2006 2:20 am
	To: w3c-wai-gl@w3.org
	Subject: Reworking 1.1
	
	

	In closing out the issues I found that there were several 1.1
issues that we did not address yet

	 

	1)       All CAPTCHA except logic puzzles are currently outlawed
by our guidelines.  Logic puzzles are a problem for cognitive and also
for CAPTCHA developers since you can't generate a large enough set that
they can't be cataloged and handled by robots.

	2)       Sensory tests  (visual test or exercises, auditory
tests or exercises)  (e.g. colorblindness tests)

	3)       Spelling test  (do you need to caption or provide
transcripts for audio files used in spelling tests?)

	4)       There is a visual representation of a hurricane showing
the direction of air follow throughout.   Where an obstruction is
encountered the flow directions distort all around the obstruction.
This is presentation of information with non-text content - but it is
not possible to present this in a text alternative.  We have no
exception for this.  Only for functional non-text content.

	5)       Some non-text content is both informational and
functional.  

	6)       We currently have an SC under "Guideline 1.1 Provide
text alternatives for all non-text content." that doesn't involve
providing alternate text.

	 

	 

	To address all these I have reworked the L1 SC to cover these
issues. 

	 

	 


	Guideline 1.1 Provide text alternatives for all non-text
content.


	 


	1.1.1 For all non-text content, one of the following is true:


	 

	*         If non-text content presents information or responds
to user input, text alternatives serve the same purpose and present the
same information as the non-text content. If that is not possible, text
alternatives identify the purpose of the non-text content; 

	 

	*         If non-text content is multimedia, live audio-only,
live video-only, a sensory-stimulus specific test or exercise, or
primarily intended to convey a sensory experience, text alternatives
identify the non-text content with a descriptive label. (For multimedia
-see also, Guideline 1.2)

	 

	*         If non-text content is an automated Turing test,
different forms are provided to accommodate multiple disabilities.

	 

	*         If non-text content is purely decorative or used
solely for visual positioning, it is implemented such that it can be
ignored by assistive technology.

	 

	 

	 

	It is all in one SC because two of the four cannot stand as
separate SC under the guildeline.

	 

	For the reasons for the rest of the changes - see the 6 issues
above. 

	 

	I will put this out to survey in a bit.

	 

	If this looks ok - I will rework the How to Meet docs.

	 

	(this also removes a large amount of redundancy from the HTM
docs 

	They will now fall into one - and the parallel presentation
makes it much easier to explain what to do. 

	 

	 

	 

	
	Gregg
	
	------------------------

	Gregg C Vanderheiden Ph.D. 
	Professor - Depts of Ind. Engr. & BioMed Engr.
	Director - Trace R & D Center 
	University of Wisconsin-Madison 
	<http://trace.wisc.edu/ <http://trace.wisc.edu/> > FAX
608/262-8848  
	For a list of our list discussions http://trace.wisc.edu/lists/
<http://trace.wisc.edu/lists/> 

	The Player for my DSS sound file is at http://tinyurl.com/dho6b
<http://tinyurl.com/dho6b>  

	  <http://trace.wisc.edu:8080/mailman/listinfo/> 

	 

	 
Received on Monday, 13 March 2006 16:28:27 GMT

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