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Re: Adaptive Image Element Proposal

From: Laura Carlson <laura.lee.carlson@gmail.com>
Date: Thu, 6 Sep 2012 12:55:59 -0500
Message-ID: <CAOavpvcE-Kw3U7SNX2FdA9tjS=KeiRxC0DGqa9VMEUJ-n+1T5A@mail.gmail.com>
To: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Cc: Adrian Roselli <Roselli@algonquinstudios.com>, Mathew Marquis <mat@matmarquis.com>, Peter Winnberg <peter.winnberg@gmail.com>, Steve Faulkner <faulkner.steve@gmail.com>, HTML WG <public-html@w3.org>, "public-respimg@w3.org" <public-respimg@w3.org>
Hi Lief,

> Needless complexity: The complexity is related to lack of support for
> <picture>

That's right. That is why Mat will be changing the draft spec to use
<img> with alt for the short text alternative not <picture> and a new
text alternative method.

He will be monitoring the outcome of Issue 30 for how to proceed on a
long text alternative.

> Even @longdesc is very complex if you want to implement
> support for it in AT which do not support it already.

Recent research finds that modern screen readers have good support for
the longdesc attribute [1]. A collection of tools that provide support
for longdesc exists [2] for those that need or require that support.
Users who want to access long descriptions supplied via longdesc,
whether they are sighted or not, have a choice of options to do so.
The claim that longdesc isn't exposed to some users is outweighed by
the concrete examples of it being exposed in accessible ways.

On March 11, 2011 professional content producers at the Digital Image
and Graphic Resources for Accessible Materials Center (DIAGRAM)
addressed longdesc support for users. Their testimony states:

"features developed to help people with specific disabilities also
assist other users, and this is true for long image descriptions.
Today, for example, Firefox and Opera allow the user to open a context
menu over an image and choose to see the long description on the
screen, if @longdesc is included with the image. This is an excellent
tool for assisting sighted students with learning disabilities who
need textual reinforcement when deciphering the contents of a
complicated image."

Since March 11, 2011 user agent implementation has grown [4]. The
following examples clearly demonstrate this and how longdesc is
machine readable.

* A new longdesk FireFox extension has been developed that adds a link
to the longdesc under images that provides one. It makes the longdesc
activation easy and intuitive for sighted users who wish access. [5]
* For those who would like an indication of when longdescs are
available on a page without interfering with page design, a new
TellMeMore Opera extension has been developed. It respects visual
design and does not force an on-page visual encumbrance. Instead it
provides an icon in the chrome to indicate when descriptions exist.
Then, upon activating the icon, the user is presented with a popup
containing a list of all descriptions available along with their
thumbnail images. [6]
* New direct replacement functionality has been provided via a
scripted implementation. [7]
* A longdesc favelet by James Thatcher first announces the number of
images on a page that has longdesc attributes. Then it highlights each
image on the page that has a longdesc and provides on-screen text
links to each corresponding description. It provides universal
functionality of longdesc in browsers such as Chrome, FireFox,
Internet Explorer, and Safari. [8]

New text has been specified for HTML5's 10.6.1 rendering section via
Change Change Proposal [9], which illustrates how longdesc can be made
discoverable [10]. It will encourage browser vendors to improve
support. As Anne van Kesteren has said, examples in the specification
serve as an incentive to vendors: "It's an incentive to get the
software fixed." [11]

Best Regards,

[1] http://www.d.umn.edu/~lcarlson/research/ld.html#at
[2] http://www.d.umn.edu/~lcarlson/research/ld.html#tools
[3] http://lists.w3.org/Archives/Public/public-html/2011Mar/0270.html
[4] http://www.d.umn.edu/~lcarlson/research/ld-ua.html
[5] https://addons.mozilla.org/en-US/firefox/addon/longdesk/
[6] https://addons.opera.com/en/extensions/details/tellmemore/
[7] http://blog.ginader.de/dev/jquery/longdesc/examples/webaim/index.php
[8] javascript:void((function(){var%20element=document.createElement('script');element.setAttribute('src','http://jimthatcher.com/IBM/js/LongDescription.js');document.body.appendChild(element)})());
[9] http://www.w3.org/html/wg/wiki/ChangeProposals/InstateLongdesc#Details
[10] http://www.d.umn.edu/~lcarlson/research/ld-rendering2.html
[11] https://www.w3.org/Bugs/Public/show_bug.cgi?id=13531#c6
Received on Thursday, 6 September 2012 17:56:50 GMT

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