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Re: More about <alt>

From: Gregory J. Rosmaita <oedipus@hicom.net>
Date: Wed, 5 Sep 2007 01:07:51 -0400
To: public-html@w3.org
Message-Id: <20070905045752.M2633@hicom.net>

if IMG is preserved as an empty container for "backwards compatibility", 
then it is ESSENTIAL that the alt and longdesc attributes be retained -- 
the former as REQUIRED, the latter as optional, but highly encouraged, 
and even -- in some circumstances, such as an educational institution's 
online course work -- required...  if IMG is deprecated, UAs will STILL
have to support/enable exposure of alt and provide a configurable method
for presentation to the user AND the replacement element or elements,
MUST have a short descriptor and a long descriptor form -- that's the 
SVG model, and that should be the HTML WG's model -- provide a terse,
required descriptor, and make available, either by requirement, by 
voluntary action on an individual author's part, or when prompted to do
so with an ATAG compliant authoring tool (http://www.w3.org/TR/WCAG10
and http://www.w3.org/TR/ATAG20/), provide a mechanism for providing a 
rich long description -- or one of a set, each in a different natural 
language, served via content negotiation...

look at it this way, and i do mean visualize this:

you can get a site preview through a MouseOver or other hover event on 
ask.com, right?  you can get a thumbnail of an image in a file listing, 
right?  you can get an explanation of that weird icon in the tabpanel 
through a hover event -- all of these are examples of brief visual 
"descriptions" being offered to the user -- they are a terse means of 
explicitly stating that X (in this case, IMG) equals Y (in this case, 
ALT) which performs function Z (in this case, title); detailed 
information is available at the target of the longdesc attribute

users don't always need or want to have everything explained in detail,
but if i land, as i did in an earlier thread, on a short descriptor 
such as:

"Snapshot of a KDE Desktop"

might i not want a description of a KDE desktop's default GUI "look 
and feel" so that i can communicate with sighted technical support, let 
alone colleagues and assistive technology?  or, i might be satisfied 
that there, in the document instance, is a picture of a KDE desktop -- 
whoopee! big deal, keep moving on...

a user can't be expected to provide granularity where none exists; it 
must be provided for the user by the document's author, or by an 
accessibility API, ARIA, and (for those whose equipment cannot handle 
scripting and/or can't afford a machine with enough processing power 
to even perform scripting) proxies and RDF schemas

we're only talking about 2 levels of granularity -- ALT being the 
thumbnail or OnHover preview event and longdesc being the equivalent
of opening up that file or picture and taking as close a look at it 
as needed...  just because 2 levels of granularity are provided via 
the existing IMG element, doesn't mean that the user HAS to hear the 
complete description of the graphical resource, but unless there is 
a mechanism whereby one can be provided, it simply isn't available 
when it is needed...

this is especially important in the ultra-visual culture in which we 
live -- most of those in this working group who can see, hold such 
iconic images in its collective unconscious as the "look and feel" of 
Google, Yahoo! -- even the iconic W3C logo, are all examples a shared 
understanding that is simply unavailble to some, unless someone takes
the time to provide a long description, or provides an EARL processor 
proxy, which would allow third parties to annotate graphics in other 
parties' web space...

the only other analogy which i can provide is the difference between 
"visiting" the louvre by viewing only thumbnails of its entire 
collection in digitalized form, and being able to fully process a 
digitized work of art, such as the digitalized image of a sculpture 
which can be viewed from any angle or perspective, which is the 
second best thing to actually going to the louvre (where, by the 
way, the staff is quite accomodating to blind visitors, at least in 
my experience)

the user should always have the final say over the level of 
granularity needed by that individual user, which is a factor which 
may and will change, from activity to activity -- that is why, if 
null or invalid alt content is allowed to be ignored, it MUST be at 
the user's express command, not removed from the attribute set 
defined for IMG in the HTML 4.01 Strict DTD

sometimes a glance or a signpost is sufficient, and sometimes -- more 
times than most would admit/think -- it is necessary to know in detail 
the contents of a graphical component of a document instance; it's 
like driving: sometimes the signs are sufficient, sometimes you need 
a map, and sometimes, you just need to pull over and ask someone...

A conclusion is simply the place where someone got tired of thinking.
                                                      -- Arthur Bloc
Gregory J. Rosmaita - Gregory.Rosmaita@gmail.com
       Camera Obscura: http://www.hicom.net/~oedipus/
Received on Wednesday, 5 September 2007 05:08:06 UTC

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