Re: New issue: IMG section of HTML5 draft contradicts WCAG 1 & WCAG 2 (draft)

Two images without explicitly associated text alternatives.
1 is an image is decorative that the author has accidently left off
the alt, the other is "critical content" that the author could not
provide an alt for whatever reason
1 can be safely ignored, the other should be brought to the attention
of the user.

<img src="abc.jpg">

<img src="xyz.jpg">

How is Assistive Technology  supposed to reliably determine this?
Given that these two images could be the same, but their meaning
differ widely depending on the intent of the author in regards to
their use.

regards
steve

On 11/04/2008, Laurens Holst <lholst@students.cs.uu.nl> wrote:
> Henri Sivonen schreef:
>
> >
> > On Apr 11, 2008, at 11:23, Steven Faulkner wrote:
> >
> > > 5.  Conclusion:  barring the introduction of new, good
> > > reasons for a change, the failure of the HTML5 draft to make
> > > @alt on <img> an across-the-board requirement (even if sometimes
> > > it has the value of &quot;&quot;) is a bug.
> > >
> >
> > Hixie's email on the matter and my previous email(s) on the matter gave a
> reason:
> >
> > A piece of software gets images from somewhere and puts them automatically
> out on the Web. What should the developer of that piece of software program
> it to do when an image arrives from whatever pipe they arrive from without
> alternative text? How do you require a program to emit something it simply
> doesn't have without faking it with junk?
> >
> > (Note: Saying that the program should block until human intervention won't
> be a viable approach. A product that did that would only be supplanted by
> products that don't. Saying that such products should be programmed to
> output invalid HTML isn't a viable answer, either. Saying that the program
> should emit alt='' would lose information about lack of data vs. marking the
> image as decorative.)
> >
> > Should I conclude that you don't count the reason as a good reason?
> >
>
> I assume that the WCAG wants the alt attribute to be required, so that
> validators must throw an error for it and force web page authors to
> explicitly consider the attribute and a proper value for it.
>
> Without error message, page authors will not consider the alt attribute,
> even when there is no technical reason why their images can't contain it (as
> the spec mentions in its prose).
>
> I have to say I agree with this reasoning.
>
> By specifying an alt="" attribute, the use case that you mention is still
> served. At least the page author will have considered the attribute, and the
> choice to not provide one was a conscious choice. I do not think the
> distinction between 'irrelevant image' and 'no alternate text available'
> that you provide is very valuable to the end-user, and especially not worth
> the trade-off.
>
> ~Grauw
>
> --
> Ushiko-san! Kimi wa doushite, Ushiko-san nan da!!
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Laurens Holst, student, university of Utrecht, the Netherlands.
> Website: www.grauw.nl. Backbase employee; www.backbase.com.
>
>
>


-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

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Received on Friday, 11 April 2008 12:06:13 UTC