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Re: longdesc using #id

From: Hakkinen, Mark T <mhakkinen@ets.org>
Date: Fri, 23 Nov 2012 22:21:29 +0000
To: David MacDonald <david100@sympatico.ca>, 'HTML Accessibility Task Force' <public-html-a11y@w3.org>
CC: "chaals@yandex-team.ru" <chaals@yandex-team.ru>, 'Steve Faulkner' <faulkner.steve@gmail.com>
Message-ID: <82FAC27AD99C2D44994556F25E7812431914D614@SN2PRD0710MB370.namprd07.prod.outlook.com>
I also agree with Chaals.  Longdesc descriptions may exist within page, or
externally. Both should be supported with appropriate UI.

On 11/23/12 8:58 AM, "David MacDonald" <david100@sympatico.ca> wrote:

>I also concur with Chaals that this is a use case that would be good for
>Longdesc, and that HTML4 allows for it, but that the spec provided no
>example, and did not mention it ...
> I support its inclusion in our extension... I just think we're being a
>strident to say its non-implementation for over 15 years is a "bug".
>	>> ... there have been implementation reports that some screen
>reader / browser combinations don't handle this well.
>Is there one implementation (Browser/AT combination) that *does* handle it
>well? Or was there *ever* a combination that did?
>I think we should say it like it is... that HTML4 does allow for a #id to
>point to the same page, but no one ever did... and at the time, if I
>remember correctly, the team was looking for an alternative to "D" link,
>the thinking was a description separate page, because they thought sighted
>people didn't need the description... (there was not much understanding at
>the time of the needs of the cognitive community)
>There is room to interpret HTML4 this way, but there has never been an
>implementation of it in 15 years, and therefore it is effectively a new
>proposed behaviour, which I wholeheartedly support.

Well, not "never".  The pwWebSpeak browser [1] was the first to implement
longdesc support, and to my recollection, we had it working within days of
the attribute being proposed. A quick search of the w3.org pulls up my
commitment [2] to include it in our browser back in September, 1997 (along
with my, in hindsight, valid concerns on adoption). It still works,
recognizing the last version we released was in 2000.

Implementation was straightforward in pwWebSpeak.  Images with longdesc
were announced as having a description available, and a keystroke command
was available for accessing the londesc (loaded as a new page).  Exit from
the longdesc was achieved by hitting the back button.  We had examples of
both within page (#id) and external links, for testing purposes, and of
course, we tested with the few longdesc's in the wild.


[1] http://www.talkinginterfaces.org/artifacts/pwwebspeak/

[2] http://lists.w3.org/Archives/Public/w3c-wai-wg/1997JulSep/0296.html

>David MacDonald
>CanAdapt Solutions Inc.
>  Adapting the web to all users
>            Including those with disabilities
>-----Original Message-----
>From: Steve Faulkner [mailto:faulkner.steve@gmail.com]
>Sent: November-23-12 6:36 AM
>To: HTML Accessibility Task Force
>Subject: Re: longdesc using #id
>Chair hat off.
>I concur with chaals on this.
>On 23 Nov 2012, at 14:21, "Charles McCathie Nevile"
>> (chair hat off)
>> Hi,
>> there has been some discussion about longdescs whose URL is a relative
>reference to somewhere in the page. And there have been implementation
>reports that some screen reader / browser combinations don't handle this
>> I think that is a bug in the relevant software (maybe screenreader,
>the underlying browser). There is a demo of longdesc that Patrick Lauke
>wrote to go with his Firefox extension, last updated in 2008, which uses
>internal page links, and the extension as well as the browser-native
>implementations of iCab and Opera all handle the case of an internal
>reference just as they would an external one.
>> In the original HTML specification of longdesc, the value of the
>is given as URI, and that can be an internal or an absolute link (the same
>as the href attribute for a link). I don't know of any evidence that
>longdesc was intended to only work on external pages, despite some
>implementations failing if you don't do that.
>> During the seemingly endless discussions of ISSUE-30 in the HTML WG, one
>argument raised against longdesc was that it forced the description to be
>a separate page. This assertion is not backed up by the spec, but by some
>> It seems to me that there are valid use cases for having the description
>on the same page as an image, and pointing to it. So I think the HTML 4
>was right, and we should re-affirm that, and file bugs against the
>that doesn't implement it properly. (I have already done this for the
>> cheers
>> Chaals
>> -- 
>> Charles McCathie Nevile - Consultant (web standards) CTO Office, Yandex
>>      chaals@yandex-team.ru         Find more at http://yandex.com
Received on Friday, 23 November 2012 22:22:04 UTC

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