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Re: What does "works" mean here? Re: 48-Hour Consensus Call: InstateLongdesc CP Update

From: James Craig <jcraig@apple.com>
Date: Mon, 24 Sep 2012 09:34:59 -0700
Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>
Message-id: <15FBD416-023B-403E-86E3-13F74753C7A0@apple.com>
To: Charles McCathie Nevile <chaals@yandex-team.ru>
On Sep 23, 2012, at 5:42 AM, Charles McCathie Nevile <chaals@yandex-team.ru> wrote:

> (in my initial reply to your proposals I made a poorly-explained comment
> about using the technique under 500% zoom plus high-contrast. This is in
> part an attempt to provide the explanation I should have given at the
> time).


> On Sat, 22 Sep 2012 03:21:10 +0200, James Craig <jcraig@apple.com> wrote:
>> On Sep 17, 2012, at 3:06 PM, Gez Lemon <g.lemon@webprofession.com> wrote:
>>> [longdesc] is better supported and more reliable than no solution at all for
>>> providing a long description for complex images.
>> Here are six examples. Three of which work today. One which works in all implementations, which is more than can be said of longdesc.
>> http://cookiecrook.com/longdesc/
> I presume the one you claim works today is
> http://cookiecrook.com/longdesc/iframe/
> As I understand this teachnique, (and from my own testing) it only works
> for people who are browsing with images off, or using a screen reader.

That's the target audience, yes.

> While this describes a well-known accessibility scenario, if those are
> indeed requirements the technique also fails in some very common
> accessibility scenarios.
> In particular, many people with visual disabilities who would benefit from
> long descriptions do not turn images off. And thanks to the broad support
> in modern systems for things like magnification and high contrast such
> people are likely to have a setup that meets their needs better than
> assuming a screenreader is somehow the answer to visual accessibility
> problems.
> I may well have misunderstood something important, or you may not yet have
> explained it because you thought it was obvious. But if my understanding
> is correct, then I think there are some serious problems with the iframe
> solution proposed.
> Because there is no "strong association" that software could rely on (as
> most screenreaders do for longdesc), this effectively shifts the burden of
> orienting the user from a handful of software developers - to all authors.
> There is a reason why the proposed statement of principles for designing
> HTML suggests that should be avoided. If your example doesn't work with
> images turned on, I suggest it as evidence that this approach isn't likely
> to be a great improvement on what we have today even given that we manage
> to get faster adoption among users than would be possible for longdesc.

These are fair points, but I still believe the negatives are outweighed by the positive that implementation support for iframe is universal.

Received on Monday, 24 September 2012 16:35:42 UTC

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