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Is CHOICE a good solution? (was RE: Is longdesc a good solution? (was: Acessibility of <audio> and <video>))

From: John Foliot <foliot@wats.ca>
Date: Mon, 8 Sep 2008 11:34:04 -0700
To: "'James Craig'" <jcraig@apple.com>
Cc: "'Lachlan Hunt'" <lachlan.hunt@lachy.id.au>, <wai-xtech@w3.org>, <public-html@w3.org>
Message-ID: <006801c911e1$7924abd0$1b2e42ab@stanford.edu>

James Craig wrote:
> 
> In this case, no long description is needed.

>From your perspective maybe.  Perhaps not the best example, but certainly
relevant.  I wonder aloud how many blind readers following this thread would
argue that the fuller explanation of that particular image that I provided
was of zero value, especially the description of the mission patch?


> Certainly better alt text
> should be there, but the point of the image is adequately described by
> the title ("Shuttle Atlantis at the Launch Pad, Set for Hubble
> Mission") and the caption ("Atlantis' crew, targeted to launch on Oct.
> 10, will upgrade the Hubble Space Telescope, extending the life of the
> groundbreaking observatory. [link] Hubble Servicing Mission, [link]
> Space Shuttle Section").

Yes, the *reason* for the image is clearly there, but a full description of
the image is missing - two very separate and different things.  We could
have an "angels on the head of a pin" discussion about whether or not users
would want to know *what* the image is about, but the reality is that it
would come down to the individual user.  @longdesc provides an unobtrusive
method of providing that information, without the "clutter of minutia"
argument you make: it provides an option, a choice, to find out more about
the image if/when content authors care to share that information.  @longdesc
does not impose itself on content consumers, but instead avails itself if so
desired.  The subtlety or this point seems to be missed in this discussion.


> It is irrelevant that the image contains two photos from different
> perspectives and a graphic of the mission patch.

According to whom?  I am not being antagonistic here, but where-else (for
example) will users get the detailed information that I provided regarding
the patch (there *was* a reason I spent the time describing it).  The
relevancy or irrelevancy of providing information to end users is not for
authors to decide:  you, as a sighted user can see that patch (and in fact
the whole photo collage) and study it or ignore it as you choose - a
non-sighted user does not have that ability, and thus they are being
short-changed.


> It some respects, it
> may even be considered a decorative image. All three of those main
> sections contain large images that are intended to get the viewer to
> click through to the related article, the images are not there for
> their own sake.

Agreed, they are not - they actually serve multiple functions: they provide
a visual 'teaser' to induce readers to find out more, and they serve to be
the recipient of the anchor tags.  However, while the second and third
images (the rings of Saturn's moon, and Tropical Storm Hanna) are probably
sufficiently covered by @alt, the detail of the first image, and
*especially* the patch, suggests that an additional layer of
explanation/description might be appropriate. 

*IF* I, as an accessibility advocate and responsible government webmaster
wanted to meet the letter of the law, and sought to ensure a fuller
description of that image, as well as make it the link that it is right now,
how would I do it?  Focus on the problem, not the specific example I pulled
off of the web to try and make this a real discussion.


> 
> Sometimes overly-detailed accessibility is championed at the expense
> of usable accessibility. Consider how often you "skim" content
> sections. Blind people don't want to be bogged down by minutia any
> more than sighted users do.

Correct.  However, sometimes, just sometimes, they *DO* want to know the
minutia of the image, and in that instance, how can we provide it to the
non-sighted, without imposing it on everyone else?  Currently, we can do it
with @longdesc.


>
> When @longdesc was the best solution, I argued that it should only
> rarely be used, specifically in the case of charts and graphs, where
> data visualization represents real page content that requires a longer
> explanation than @alt will allow.

I agree that this is the most useful time to use @longdesc, but do not
suggest that it is the *only* time that it can/should be used.  Conversely I
too counsel that there is such a thing as going over-board, and do not for a
minute suggest that every image used on a webpage should have @longdesc.
But when it is necessary, there is nothing else currently that will do the
same as what @longdesc does.


> Even image galleries (such as Flickr or a museum website) should
> rarely, if ever use longdesc. Yes, the main point of the content is
> the image itself, but that content should be described on the page. In
> the case of artwork, this usually provides benefit to non-disabled
> users, too. Imagine an image's in-page, visible long description
> provides detailed discussion of the artist's intention in his choice
> of color, and the form contrast or dynamic angular motion of the
> painting.

So we return to image galleries again.  This is/was covered in the @alt
discussion, where, at the end of the day so long as *a* method of linking
text to a visual asset is provided then the image could be deemed
conformant.  Not *always* @alt (although that is the best-practices
recommendation), but "when you can't provide @alt" other means now exist to
do the linking, and as long as you use one of them, then you are good-to-go.
This solution highlights the real answer - choice.  @longdesc is and should
also be one of those choices... Let's stop arguing about the whether one
image can or should have a long description attached, and let's talk about
providing choices.  @longdesc currently fills a niche that no other element
or attribute fills, and for that reason alone it has value.


> This kind of detail enlightens all viewers, and it doesn't need to be
> visible by default. The web comic, Penny Arcade (It may have been a
> different comic), used to have a drop-down section of the page that
> had a data table listing characteristics of each pane, including which
> characters were visible, the dialog, and any background information
> including links to events or jokes in previous strips that may have
> been missed by anyone but a regular reader. Though not initially
> visible, this information was useful for numerous reasons.

See, there's another "choice", that ensures access to fuller information on
demand.  It doesn't shove it down your throat, it does not impose itself on
you, it simply makes it available *if* you, as an individual consumer,
wishes to know more.  We need lots of elegant solutions like this, and
currently @longdesc hints at the ability to be another type of elegant
solution.  UI's to date haven't taken full advantage of this, but there *is*
progress being made, and as Leif pointed out in a separate email, exposing
and using @longdesc is fairly easy using JavaScript.  Maybe instead of
dismissing @longdesc out of hand, smart and talented developers should start
exploring creative ways of using @longdesc and share these ideas to the web.
There's a pro-active and positive challenge for you!


> 
> 1. It increased the accessibility for blind readership.
> 2. I, for example, didn't know most of the character's names, so I
> could learn them by looking in the "long description" section. 3.
> Google could more accurately index the content of each page, so
> people could search for content by a phrase they remembered. 
> 4. etc.
> 
> All without the use of longdesc.

Right, but with a non-trivial amount of developer work, and a significant
amount of screen real-estate that may or may not be appropriate in all
instances.  It is one choice, but only one of potentially many possible
choices.


> 
> The "Visual Complexity" gallery <http://www.visualcomplexity.com/vc/>
> has loads of examples where, in its original context, each graph or
> chart should probably have had used longdesc. On the VC site however,
> even though the images are charts and graphs, longdesc is not required
> because each item's page discusses the artistic data visualization
> technique used, and in the context of the gallery, the detail of the
> data itself is irrelevant.

Correct - *IN CONTEXT* @longdesc is probably not required for this site, as
the point is not to convey the information about the values expressed in the
charts, but rather to discuss "artistic visualizations".  And yet...

Let's look at an example: 
http://www.visualcomplexity.com/vc/project_details.cfm?id=592&index=592&doma
in=

"This diagram displays the 20 biggest cross-border sovereign wealth fund
deals since 2005. Each line represents a deal, with thickness scaled by
value of deal and color the nationality of the primary buyer. The diagram
also highlights the financial advisers and lawyers who worked on more than
one of the top 20 deals."

Now, as a sighted user, I can tell you that, even from a smaller, thumbnail
version of the principle image (you know, this one:
http://www.visualcomplexity.com/vc/images/592_big01.jpg, the one without so
much as an @alt value) that the 3 largest "wealth funds" are Citigroup (the
largest) followed by UBS and Merrill Lynch.  I wonder if any of the
non-sighted readers here knew that?... 

Cheers!

JF
Received on Monday, 8 September 2008 18:34:48 GMT

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