- From: John M Slatin <john_slatin@austin.utexas.edu>
- Date: Mon, 13 Mar 2006 10:28:21 -0600
- To: "Gregg Vanderheiden" <gv@trace.wisc.edu>, <w3c-wai-gl@w3.org>
- Message-ID: <6EED8F7006A883459D4818686BCE3B3B012490CD@MAIL01.austin.utexas.edu>
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 UTC