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RE: alt use cases

From: Dailey, David P. <david.dailey@sru.edu>
Date: Mon, 5 May 2008 14:55:39 -0400
Message-ID: <1835D662B263BC4E864A7CFAB2FEEB3D258D0A@msfexch01.srunet.sruad.edu>
To: "Justin James" <j_james@mindspring.com>, <public-html@w3.org>

Justin James wrote:
 
>I think we need to take a step back, look at the use cases for alt, and see
where we need to go from here. 
 
While I probably don't agree with some of the comments you follow up with, I do rather like the methodology you propose. It seems as though the arguments have reached some sort of impasse -- if so this usually is a signal that a new perspective is needed.
 
So this is not merely a "+1" sort of remark, I did have another use case for leaving out alt tags for possible consideration:
 
the jig saw puzzle:
 
In either HTML or SVG, one generally (in the pre <canvas> world) uses a stack of identical images relocated through script and overlaid so that their clipping regions are mutually exclusive. If one were to appropriately assign unique alt's to the various images as differentially clipped (for example echoing the stacking order of the images inside the alt tags), one would be providing a solution to the jigsaw puzzle (as in a paint-by-number) which to sponsors of a friendly competition might be seen as an unfair advantage.
 
Such overlays of multiple instances of pictures might be found not only in jigsaw puzzles, but also in interweavings of multiple pictures, morphings between pictures, affine distortions of pictures,  indeed in many script-driven image analytic fragmentations of images.  One can argue that the failure to provide unique alts to each of a series of programmatically overlaid images is  consistent with authorial intent rather than through authorial neglect. Whence, if modern browsers choose to punish such pages it will have been through their neglect rather than through intent of the spec.
 
In cases such as the above, it seems as though the meaningful place to put an alt attribute would be in the superordinate heading (the <g> or the <span>) containing the pile of otherwise identical images -- though in truth I'm not sure what a screen reader would do with 1000 images stacked atop one another, with different chunks of pigment revealed through clipping paths.
 
David
Received on Monday, 5 May 2008 18:56:04 UTC

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