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Re: Natural Associations [was Re: Illustration]

From: Anne Pemberton <apembert@erols.com>
Date: Tue, 15 May 2001 16:53:45 -0400
Message-Id: <>
To: "Sean B. Palmer" <sean@mysterylights.com>, <w3c-wai-gl@w3.org>

	After a couple of reads, and a jump to the site to find out what PF was,
I'm still not sure what you are doing. I understand that "repurposable
content" is fancy talk for "text" ... (Is there any other kind of
repurposable content that could be included?)

	If I understand correctly, your starving babies example, under the current
situation would be:

        <IMG SRC="babies.gif" ALT="The starving babies were in desperite

	which you would change to

	  <ILLUS SRC="babies.gif"> The starving babies were in desperate
condition. </ILLUS>   

	Unfortunately, I'm not seeing that this is an improvement. What am I missing?



At 06:57 PM 5/15/01 +0100, Sean B. Palmer wrote:
>[A PF matter, with great relevance to GL issues.]
>In the XML Accessibility Guidelines (XML GL) currently, we have the
>following guideline and checkpoint:-
>Guideline 1 Ensure that authors can associate multiple media objects
>as alternatives
>1.1 Make sure this is done in the most natural way possible [ignore
>the @@ and the priority].
>]]] - http://www.w3.org/WAI/PF/XML/gl-20010422
>At the moment, PF is undertaking to edit this guideline from its
>current obfuscated form into something with a little more impact. In
>doing so, we have found that it overlaps with some issues that GL have
>necessarily appropriated to themselves.
>In our case, we have the guideline "Ensure that authors can associate
>multiple media objects as alternatives" ... what we are saying is that
>as far as the schemata for data-oriented applications (see the
>document for a definition) are concerned, we want to enforce the
>ability to tie in some repurposable equivalent alternative with some
>content who's semantics may not be repurposable.
>Typically, this is represented by the age old "alt" text example in
>XHTML, viz.:-
>   <img src="banner.gif" alt="Welcome To My Site" />
>However, this can clearly no longer be taken as an acceptable example
>by itself, because it's a subsumption of the complexity of
>relationships that occur between content of different modalities.
>Thus, what I (we) are asking is for rationalization of the above where
>appropriate (e.g. in guidelines) - the fact that it's a subsumption
>should (at least) always be noted, and preferably) be expanded upon.
>For an example of what we want to achieve, let's take the XHTML
>"problem" again. What the alt text example says is that textual
>alternatives must be provided as an annotation for the image... in
>other words, we are thinking in terms of "I have an image, and now I
>have to provide some equivalent alternative in the form of an alt
>attribute". It is quite possible, and in fact often required for some
>content authors to annotate a concept, a run of text, or marked up
>content with an image. This isn't possible in XHTML 1.0/1.1/m12n
>(which is a great shame), but should be in 2.0, so for example:-
>     The starving babies were in a desperate state.
>could become:-
>     <illust src="babies.gif">The starving babies were in a desperate
>       state</illust>
>Note that this is not simply limited to illustrations - the ability to
>associate a variety of media alternatives no matter what the modality
>should be pervasive throughout all XML data-oriented applications.
>The question thereafter becomes about UI: how do we associate the run
>to the image, where do we put that image, what do we do with the
>image? That's beyond the scope of XML GL (although may be in the scope
>of GL), but it could be that using some remote styling mechanism, one
>can explicitly style where they want the content to appear, and
>exactly how it should be styled. cf. 2.1 in XML GL. There's also the
>question of multiple illustrations for one run of text... note how
>much more interesting it becomes when (for example) you add the images
>to the text rather than the text to the images.
>So that's one small aspect of what we mean by natural. Another is the
>question of what we mean by repurposable images themselves, for
>example SVG. One view of the relationship here is that SVG enables
>people to export bits of semantics from the image itself. Others may
>prefer to think of it as the old annotation fashion again, i.e. adding
>the descriptions to the image as a secondary effect. This is not
>something that languages constrain upon people - it allows us to
>choose, which is correct.
>Hence, a "technique" for what we mean by "natural association" is a
>mixture of both not being constrained by current technologies as to
>the choice of semantic association mechanisms (and hence removing
>restrictions on the form of the language itself, and removing
>accessibility barriers).
>As for checkpoint 1.1 (soon to be 1.3 due to document reorganization)
>itself, I propose that WAI PF change the text to the following:-
>1.3 Provide unconstrained mechanisms for semantically associating
>content of different modalities with one another. That is to say, if
>the semantics of part of a document instance are unlikely to be
>accessible to all of your readers, provide equivalent alternatives
>which facilitate understanding by other means.
>(Note that I'm using a modified earlier proposal for the explanatory
>text from Dave Pawson after the "-", which I found excellent).
>Kindest Regards,
>Sean B. Palmer
>@prefix : <http://webns.net/roughterms/> .
>:Sean :hasHomepage <http://purl.org/net/sbp/> .
Anne Pemberton

Received on Tuesday, 15 May 2001 16:45:17 UTC

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