- From: Gregg Vanderheiden <GV@trace.wisc.edu>
- Date: Mon, 25 Nov 2013 00:23:09 +0000
- To: David MacDonald <david100@sympatico.ca>
- Cc: Janina Sajka <janina@rednote.net>, HTML Accessibility Task Force <public-html-a11y@w3.org>, GLWAI Guidelines WG org <w3c-wai-gl@w3.org>, Gregg Vanderheiden <gv@trace.wisc.edu>, "<kirsten@can-adapt.com>" <kirsten@can-adapt.com>
- Message-id: <FB2D5F15-98A6-4877-A1AF-A9B16FE8ADC0@trace.wisc.edu>
RESENDING DUE TO BOUNCES ---- ALSO MADE IT EASIER TO READ Interesting discussion I think I would summarize it (and view it) this way. (these are just my thoughts and nothing official) FIRST -- I thin we should remove the FAILURE we have for missing ALT because it fails the test for being a FAILURE. FAILUREs are things that are ALWAYs failures. (and they need to be common) This is common - but it is not alway a failure. To make this into FAILURE (that is always a failure) would require that we rewrite it to essentially sound like the success criterion -- which isn't helpful. This USED to be a failure because we only had one technique that was accessibility supported -- so if you didn’t do that you failed the SC. But this is no longer true -- (or rapidly becoming not always true) -- so this is no longer a guaranteed failure - and should be removed. That doesn’t mean that not having ALT text isn't a failure. It just means that it isn't a guaranteed failure (the qualification for something being documented as a failure. So -- now the question becomes -- is using ARIA sufficient to pass the SC. They key here is "does the page make the information available to users who can't see the image" - given the current state of AT and browsers, and the support for ARIA. Or in short -- is it "accessibility supported". Can people use AT to actually get at the information and have it presented to them. Thus --IF the AT of the user's of your pages will present the information with just ARIA mark up -- THEN you can use ARIA and it will meet the SC. But IF (all?) the users of your pages do not have AT that will present the ARIA marked up information -- THEN ARIA will not meet the SC. Two things have to be true for the information to actually be accessible (usable by people with disabilities). The information has to be there in non-visual (or as I prefer to say "universally presentable") form --- AND --- there have to be tools that know where to find it and do present it to those who need it in different forms. We need both the sender (page) AND the receiver (Browser/AT) work together to have successful passing of information. The report Janina cited was the status in 2009, and it is good to revisit the question now that it is 4 years later. Unfortunately for many the report might still be true today. I won't make that call -- I will let others -- because we need to make it over again every few years. The report that Janina cited -- is an exellent place to start in that process. It is an excellent analysis and can be used to check against progress in support by AT for newer techniques to determine when its conclusions should change. ALSO - note that: EVEN IF it something may not meet the SC for public websites IT MAY meet the SC for captive audiences (e.g. employees at a company) if it is true that AT is available to all employees who use that intranet. (Again - these are just my thoughts and nothing official) Gregg -------------------------------------------------------- Gregg Vanderheiden Ph.D. Director Trace R&D Center Professor Industrial & Systems Engineering and Biomedical Engineering University of Wisconsin-Madison Technical Director - Cloud4all Project - http://Cloud4all.info Co-Director, Raising the Floor - International - http://Raisingthefloor.org and the Global Public Inclusive Infrastructure Project - http://GPII.net On Nov 22, 2013, at 6:27 PM, David MacDonald <david100@sympatico.ca> wrote: > On behalf of the WCAG working group, I have an action item to solicit > responses from the wider community regarding a proposed amendment to WCAG > failure technique F65 regarding missing ALT. Currently; if an <img> element > is missing from an ALT attribute the page fails WCAG SC 1.1.1 Level A. Some > are proposing that we allow authors to use the aria-label, aria-labelledby, > and title attributes INSTEAD of ALT. > > So under the amended failure technique NONE of the following would fail > WCAG: > > <img src="../images/giraffe.jpg" title="Giraffe grazing on tree branches"/> > > <img src="../images/giraffe.jpg" aria-label="Giraffe grazing on tree > branches"/> > > <img src="../images/giraffe.jpg" aria-labelledby="123"/> > <p id="123"> Giraffe grazing on tree branches</p> > > As you can imagine there are strong opinions all around on this so I > suggested we get a sense of what other groups such as the HTML5 A11y TF and > PF think. > > Those in favour of the change provide the following rational: > > --These alternatives on the img element work in assistive technology > --The aria spec says these attributes should get an accessible NAME in the > API > http://www.w3.org/TR/wai-aria/roles#textalternativecomputation > --They say it's easy to teach beginner programmers to just always use an > aria label on everything, rather than requiring a label on form fields and > alt on images > --They feel as a failure F65 is very strong if fails a page for missing ALT, > especially if other things work, and they would like to soften it to allow > other things that work. > --html 5 allows a <figure><legend> combination instead of alt, so they feel > WCAG will have to change F65 anyway to allow a figure with a legend, and > that helps open the door to this discussion > > Those in favour of the status quo (which fails missing alt text) provide the > following rational: > > --aria-label, labelledby and title, are not really suitable attributes for > img alternative text because they implies a label or title, rather than an > alternate text, so it is not a semantic equivalent > --title is not well supported > --some feel that the aria spec is not in any way suggesting these as > replacements to ALT. > --aria instructs authors to use native html where possible, and they could > not come up with viable use cases of omitting alt text > --there are hundreds of millions of dollars invested in current evaluation > tools, and methodologies, and this would represent a major departure from > one of the most basic accessibility convention, that is almost as old as the > web and is the "rock star" of accessibility > --it could cost a lot of money to change guidance to developers etc..., and > muddy the waters on a very efficient current evaluation mechanism > --when the figure/legend is supported by AT we can amend F65 but that is a > different issue and the semantics of this construct are OK for text > alternatives, rather than the label/labelledby/title options > --it may cause some confidence problems to WCAG legislation, because it > represents a strong loosening to a fundamental Success Criteria, an > unnecessary change that doesn't help the cause of accessibility, but just > complicates things > --ALT is better supported and the text appears when images are turned off. > --initial twitter feedback from the community is strongly against changing > this failure > > > There are probably other reasons on both sides which we hope to hear ... but > these should start it off. Please give your opinions and reasons. > > Current technique here: > http://www.w3.org/TR/WCAG-TECHS/F65.html > Proposed failure here (see test procedure) > > > > Cheers, > David MacDonald > > CanAdapt Solutions Inc. > Tel: 613.235.4902 > http://ca.linkedin.com/in/davidmacdonald100 > www.Can-Adapt.com > > Adapting the web to all users > Including those with disabilities > > > >
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Received on Monday, 25 November 2013 16:26:14 UTC