- From: Gregg Vanderheiden <gv@trace.wisc.edu>
- Date: Wed, 5 May 2004 12:59:06 -0500
- To: "'WAI WCAG List'" <w3c-wai-gl@w3.org>
- Message-ID: <auto-000027617630@spamarrest.com>
I think we are all on the same page. Now we need to figure out how to word this such that the person doesn't need to go to a non-normative doc to figure out if they passed. Yvette's latest draft: <suggestion> For non-text content, provide text alternatives. Whenever possible the text alternative should be equivalent to the non-text content, meaning it serves the same function or conveys the same information as the non-text content. If a text equivalent is not possible due to the nature of the non-text content (for example: music and visual art), provide a text label or a description. </suggestion> is closer but still doesn't define "not possible due to nature of non-text content" enough. One can see people defining that in all sorts of way including. It is visual in nature. It is meant for regular education students. It is scientific in nature. Etc. what is it that makes these different. That makes them indescribable? Or do we say, where the content can be described in X words or less? Is this really what divides what should be described from what shouldn't? Or do we just say, provide at least an X word description unless the function or content can be described in less? Thoughts? Gregg -- ------------------------------ Gregg C Vanderheiden Ph.D. Professor - Ind. Engr. & BioMed Engr. Director - Trace R & D Center University of Wisconsin-Madison _____ From: John M Slatin [mailto:john_slatin@austin.utexas.edu] Sent: Wednesday, May 05, 2004 11:13 AM To: Gregg Vanderheiden; WAI WCAG List Subject: RE: Example: Real-time feed of satellite photos Gregg, I agree that the example we've been discussing-- a real-time feed of satellite photos, in this case of Texas-- aren't really intended to create a "specific sensory experience" as per the wording of 1.1. As I noted, the solution Yvette proposed was to treat such content *as if* it fit that description-- she didn't say that it *does* fit the description, and I didn't say that either. I also agree that we can't set standards just by presenting examples, and shouldn't have suggested it. I also suggested that we might need to add additional language to 1.1 and/or address this type of content under 1.2 (another scary thought). To clarify further, I didn't really mean to propose that a "text description" should be provided. I was really thinking in terms of a "text label." The label might say, for example, "Satellite photo of Harris County, Texas: 2004-05-05 10:23:34 CDT" or something like that-- it would probably include information identifying specific parts of Harris County if the user had requested a more detailed view. Providing such a text label is feasible because the necessary information is already available in the data stream-- otherwise it would be impossible to let users specify the parameters of what they want to see. So my suggestion was that the script that collects user input and finds the image that matches what the user wants could be modified to (a) write the image to a new HTML page, and (b) write the existing text information to an alt attribute or to the screen (if the text is written to the screen, the script would set alt=""). John "Good design is accessible design." Please note our new name and URL! 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/ -----Original Message----- From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Gregg Vanderheiden Sent: Wednesday, May 05, 2004 10:02 am To: 'WAI WCAG List' Subject: RE: Example: Real-time feed of satellite photos This is an interesting approach for this example. But I think I see some problems. And we would need to find out how to do this with specification. We can't have specification by example. I don't think this one actually is a sensory experience. It is the presentation of specific information. The "big blue marble" picture of the earth may be-but not these. They just fall in the category of hard to describe in a reasonable number of words. (someone want to poke their head up into live fire and suggest what 'reasonable number of words" would be?) Hence the problem. This also doesn't deal with the issue of aggregated content in general. But we need to figure out a way to describe this or people could claim that other images are just sensory experiences too. It is a slippery slope Gregg -- ------------------------------ Gregg C Vanderheiden Ph.D. Professor - Ind. Engr. & BioMed Engr. Director - Trace R & D Center University of Wisconsin-Madison _____ From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of John M Slatin Sent: Wednesday, May 05, 2004 9:29 AM To: Gregg Vanderheiden; WAI WCAG List Subject: RE: Example: Real-time feed of satellite photos Actually, I think the approach Yvette suggested yesterday would work better than just declaring such pages to be beyond the scope of conformance. Yvette suggested that such images-- real-time feeds of satellite imagery-- could be treated *as if* they were content whose purpose is to create a specific sensory experience (i.e., like music or painting): the requirement would be to provide a brief text label or description. That text label or description could be built automatically by a script, using the identifying information that accompanies the image in the satellite feed. The text label could be coded as an alt attribute, or the alt attribute could be null (alt="") and the identifying text could be written to the screen of an HTML page which would be used to display the image. (It would be necessary to place the image on a page in order to provide the text label; this would have the added benefit of allowing a meaningful <title> element for the page as well). We may want to consider adding a phrase about real-time feeds to 1.1, or we may just want to handle this through examples. (This one might make a good example because it involves several technologies and their techniques: XHTML and scripting at the very least, with no room for direct human intervention to write alt text, etc.) Or maybe this one really belongs under 1.2? -- On a more theoretical (or at least more abstract) note, isn't there a sense in which most Web content is aggregated content? It's been true for years now that Web pages may include content that resides at multiple URIs on multiple machines. It's the magic of the rendering agent that makes it all appear to be on the same page. (I'm thinking even of very simple pages where text from one file is combined with images in other files on other servers that may be halfway around the world.) This has been part of the concept of hypertext from the very beginning: Ted Nelson called it "transclusion" back in the '80s, and I believe there was a similar notion in Engelbart's NLS/Augment system back in the '70s. John "Good design is accessible design." Please note our new name and URL! 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/ -----Original Message----- From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Gregg Vanderheiden Sent: Wednesday, May 05, 2004 8:58 am To: 'WAI WCAG List' Subject: RE: Example: Real-time feed of satellite photos I think the answer comes from our 'scoping' approach which allows you to specify which parts of your site conform at what levels. (see decision from about 3 weeks ago). Regulators may want to specify that specific parts of a site or specific types of content conform to level but our current approach is that our guidelines do not. We may later have a doc which makes suggestions on issues like this - but we do not currently have this as part of our guidelines per recent discussions and decisions. Gregg -- ------------------------------ Gregg C Vanderheiden Ph.D. Professor - Ind. Engr. & BioMed Engr. Director - Trace R & D Center University of Wisconsin-Madison _____ From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Donald F. Evans Sent: Wednesday, May 05, 2004 8:34 AM To: WAI WCAG List Subject: Re: Example: Real-time feed of satellite photos This is similar to the problem I face at AOL. How does a content aggregator conform to these standards? John M Slatin wrote on 5/3/2004, 11:41 AM: I received the following inquiry from someone who works at a state agency here in Texas. It presents an interesting challenge, and it seems like something that might furnish a good example for us. I'm also curious to know what solutions members of WCAG WG would propose in order to meet WCAG 2.0. <begin query> Our agency receives satellite photographs of Texas that are automatically formatted into jpegs and loaded to our Web site. These images are real-time, from one-hour to about 12-hours old. These are continually and automatically updated on the site. I have an opportunity to review these Web pages now because they are being revised to add additional types of satellite photos. It's my job to make recommendations regarding the content's usability and whether it meets state Web site accessibility standards. On these pages, the user selects up to four different parameters (using drop down lists) and then clicks a "display image" button. A jpeg is returned to them in their browser. Since these images are automatically updated, alt text specific to each photo can not be added. And I'm not really sure how they could be descriptive enough, anyway. Besides, the photos are not presented inside Web pages, they are just the jpeg files. The state rule says we should provide an alternative format for pages that are not accessible. I don't think that is possible in this case. Would you suggest some disclaimer text on the page stating that these images are not accessible? </end query> Thanks! John "Good design is accessible design." Please note our new name and URL! 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/
Received on Wednesday, 5 May 2004 13:59:36 UTC