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Re: LONGDESC in HTML5?

for

From: John Foliot
Date: Sep 25, 2010 2:24PM

Vlad Alexander (XStandard) wrote:
>
> Steve wrote: "I cannot disagree more. the content of the alt attribute
> can be and is many things"
>
> I don't see that. It's a really simple concept and if we keep it
> simple, people will then use it correctly.

There is simple, and then there is simplistic.

Like most of what we try to evaluate when we do our 'accessibility
reviews', determination of appropriate alt text is both subjective and
relative: an image can and does serve many different purposes in a
document, thus the alt text *should* be flexible enough to address those
issues. Applying simplistic rules does nothing to enhance or even support
user experience.

What is really important (to me) to understand is that, especially for
screen reading technology (and yes, I've been doing this long enough to
know that accessibility is more than just screen readers) - for screen
readers the user experience is as important a consideration as anything
else.

Thus, Vlad's recommendation becomes at times overly simplistic, as he is
removing the contextual piece of the user experience.


> Vlad wrote:
>
> Let's put this to a test.
>
> Test 1: In this case, should the author write alt to fit the target of
> the link or to fit surrounding content? I would argue that you should
> be able to add or remove a hyperlink from a document without affecting
> the comprehension of that document.

Steven Faulkner wrote:
>
> The issue is that you (vlad) always put an image in in the context as
> part of a narrative, yes images are sometimes used like that, but often
> times they are not, and when they are not, either your method fails to
be
> useful or you recast every instance of image use to fit your method,
neither
> are desirable or practical outcomes.

+1 to Steven.

Even when images are part of the narrative, again understanding the user
experience is required to determine useful alt text. I offer as an
example, the following image:

http://www.happywebbies.com/products/holzschlag.png

Many of us know and love Molly Holzschlag, and likely many of us too would
recognize this image of her. But what is the appropriate alt text for that
image?

Alt="Molly Holzschlag"
Alt="caricature of Molly Holzschlag"

Is the fact that it is a caricature of Molly (as opposed to an actual
photograph) important information to convey? (I argue yes). Thus the alt
text is more than just a textual replacement, as the alt text also
provides some descriptive context (it is a caricature).

However if I were to use that image as a link to the corresponding web
page where I can purchase a T-shirt with that image on it, then what would
the alt text be? Does this really make sense?

"Link: caricature of Molly Holzschlag"
(<a href="
http://www.happywebbies.com/store/detail/molly-holzschlag/"><img
src="http://www.happywebbies.com/products/holzschlag.png" alt="caricature
of Molly Holzschlag" /></a>)

Context is everything!

Vlad wrote:

> In other words, if I want to add or
> remove a hyperlink, I should not have to re-write content in the
> document. The only way to achieve this is to write content (be it
> normal text or alt text) to fit surrounding content.

I think that this is somewhat of a Straw-man argument. Web pages are not
documents in the same sense that PDFs or Word Docs are documents: they are
a type of document unto themselves, as they also include the interactivity
of hypertext links.

As such, they should be authored to be what they are, not what they might
be re-purposed to be. Suggesting otherwise (I argue) can actually degrade
the user experience of non-sighted users.


>
> Test 2: Paste the document into plain text such as Notepad or plain
> text email. Hyperlinks are removed. You are left with document content.
> So if alt is a "description/label of the link target" it's pretty
> useless here.

Omitting the fact that the image provides a link to a secondary document
(web-page) makes the advisory that an image exists somewhat useless as
well. At that point is simply becomes extraneous text, with little to no
actual usefulness to the reader (sighted or otherwise).

>
> That fits with the definition of alt as a textual replacement for an
> image. It all depends on the context (surrounding text).

"Context" with regard to web content is simply more than the sum of text
on the page; without addressing the fact that there is some interaction
associated to an image, you are not conveying the full context of the
image, nor the document that contains that image.

(As an interesting example of the concept of retaining links with web
documents - and to refute Vlad's Straw-man argument - visit a Wikimedia
page such as:
http://www.w3.org/WAI/PF/HTML/wiki/Media_Accessibility_Checklist, and then
from your browser look at the "Print Preview")

<aside>
Jukka K. Korpela wrote:
>
> But if you have a photograph of a
> house and you write alt="photo of a house" (or alt="(photo of a
> house)", which I would prefer)

I have also suggested a similar design pattern: alt="[photo of a house]",
the advantage being that square brackets are less used for other contexts,
and as they are unusual punctuation in the traditional sense, most screen
readers will omit announcing the square brackets (unless the verbosity
level is set to high) - I do this again with an eye/ear towards best user
experience.
</aside>

JF