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Re: longdesc verbiage

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Tue, 10 May 2011 09:40:19 +1000
Message-ID: <BANLkTi=72f90pgm3k8msNNMKvJVJuFwTNg@mail.gmail.com>
To: Charles McCathieNevile <chaals@opera.com>
Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>, Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
On Mon, May 9, 2011 at 11:06 PM, Charles McCathieNevile
<chaals@opera.com> wrote:
> On Mon, 09 May 2011 11:25:26 +0200, Laura Carlson
> <laura.lee.carlson@gmail.com> wrote:
>
> ...
>>
>> Chaals,
>> Do you have your proposed text ready for the metadata section [4] of
>> the change proposal?
>
> An objection has been raised against longdesc (and the use cases which rely
> on information not presented in the same page as an image) that it is
> "hidden metadata" and its quality and relevance are likely to deteriorate
> over time. While it is apparent that content which is immediately visible
> can be more readily maintained in a simplistic content management workflow,
> this argument falsely assumes that is always the case, and further falsely
> assumes that the presence of some level of degradation is a fatal problem
> for the use of longdesc to improve accessibility.
>
> In fact substantial amounts of Web content are maintained in prcesses which
> assume the presence of "hidden" metadata (which is actually readily
> discoverable) and require maintenance of that data as well as of the
> "primary" content (that is immediately visible by default). In addition,
> where an image is not changed, it is unlikely that a well crafted
> description needs to be changed, so there is no inherent degradation.
>
> While longdesc does not require "hidden" metadata (it can be used simply to
> unambiguously identify inline content of the page as a description for an
> image), there are use cases which benefit from the ability to support it.
> Images maintained as resources in a content management system, or even just
> by copying and pasting the img tag with a link inside it such as longdesc
> provides, can easily re-use the description rather than requiring that it
> too be replicated. This matches common workflows for managed content, and
> there is no reason to make it difficult. It is normal in authoring tools
> that copying objects between pages may require rewriting links appropriately
> (their destinations are, after all "hidden"), and this does not seem to
> break the web.

I'd actually dispute that a longdesc page (i.e. a resource that exists
to contain a long description of an image and potentially other
information) is "hidden". Who is it hiding from? Assuming it is a Web
page (which it will be in most cases), it is discoverable by search
engines as soon as it is linked in with something else. @longdesc
enables discoverability of that page if it hasn't been linked from
anywhere else. Putting additional information on such a page actually
makes it also more relevant to link to from other places. I really
compare it to the image pages of Wikipedia such as this one
http://en.wikipedia.org/wiki/File:Curitiba_10_2006_05_RIT.jpg, except
that Wikipedia should introduce a field with the actual long
description of the image for screen readers.

Silvia.
Received on Monday, 9 May 2011 23:41:06 GMT

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