- From: Steve Faulkner <faulkner.steve@gmail.com>
- Date: Mon, 17 Jun 2013 10:35:54 +0100
- To: whatwg <whatwg@whatwg.org>
> > Am 07.06.2013 um 23:13 schrieb Ian Hickson: > > >> <img src="..." title="image"> > > > > If you have a caption from the user (as opposed to replacement text), > then > > this is a perfectly valid option. It's as valid as the <figure> case, and > > means the same thing. > > > > [...] > > the above statement is bad advice: browsers map title to the accessible name in accessibility APIs when alt is absent, so in the following cases: <img src="..." title="poot"> <img src="..." alt="poot"> the accessible name is 'poot'. it is only when there is an accessible name already provided that title is used as an accessible description: <img src="..." alt="poot" title="description of poot"> Also note that as per the W3C HTML spec, use of the title without an alt is non conforming[1] as it does not represent a caption for an image and as you point out is hidden from a variety of users due to a long and consistent history of poor implementation. > > >> I don't know whether someones writes something like "which the > >> following figure illustrates" instead of "which is illustrated by fig. > >> 3" somewhere in the text above a figure. But this difference decides > >> whether using the figure element conforms with the spec. So a code > >> generator can only use something which is structurally and optically > >> identical to the figure element but does not have the theoretical > >> requirement to be movable to a different place in the document, e.g.: > >> > >> <div class="figure"> > >> <img src="..."> > >> <div class="caption">...</div> > >> </div> > >> > >> And here conformance checkers will complain about the missing > >> alt-attribute again ... > > > > If you use <img src="..." title="..."> it'll work (and be correct, > > insofar as anything missing alt text can be correct). > > While the title attribute might be as good as the figcaption or a > div-caption element in meaning, it differs in practice, as the element can > include further markup, the attribute cannot. The title attribute is > displayed as mouse-over text in most browsers whereas the figcaption is > usually immediately readable to anyone, just as a caption for a picture in > a book. > > I am aware that one could use JavaScript to make the text from the title > attribute immediately visible as well. But this would require further > technology on the reader’s side (JS) and complicate things more than > justified for the cause, in my opinion. > > What my markup generator actually does with captioned images is this: > > <meta name="generator" content="generator-name"> > … > <div class="figure"> > <img src="..." aria-labelledby="caption-x"> > <div id="caption-x" class="caption">...</div> > </div> > > (see also > http://www.w3.org/WAI/GL/wiki/Using_aria-labelledby_to_provide_a_text_alternative_that_serves_the_equivalent_purpose > ) > > Is there a chance that use of aria-labelledby is added to the spec > (4.8.1.1.13 Guidance for markup generators, 4.8.1.1.14 Guidance for > conformance checkers) as alternative to figure with figcaption or the title > attribute? I'd like to suggest this. It does make equally sense in my > opinion and I think I've described the use case in this thread: > > -- markup generator has no alt-text for an image > -- image has a caption that should be immediately visible and possibly > contain markup => no title attribute > > -- it is not known whether the image can be moved somewhere else in the > document => no figure with figcaption > the restriction on figure/figcaption is only in the whawtg spec not the W3C HTML spec as it was not deemed a useful or practical restriction when reviewed by the HTML WG. In fact markup generators are encouraged to use figure/figcaption for this use case [2] as the figcaption is mapped to a caption role accessibility APIs by browsers. > -- markup generator should not be pressured to use bogus alt-text to calm > easily scared customers using validators > > E.g. OCR book digitizers or markup editors strictly following the WYSIWYG > paradigm. > > Regards > Martin > > (PS: Also, thank you and Jukka for your comments that I've not replied to.) > Your suggestion of using aria-labelledby suffers from the same issue as use of title in this case, in that its value is used for the accessible name and does not represent a caption semantic unlike figcaption. [1] http://www.w3.org/html/wg/drafts/html/master/embedded-content-0.html#guidance-for-conformance-checkers [2] http://www.w3.org/html/wg/drafts/html/master/embedded-content-0.html#guidance-for-markup-generators -- Regards SteveF HTML 5.1
Received on Monday, 17 June 2013 09:37:05 UTC