RE: Technique H45 procedure description incomplete

But that's tautologous - the technique IS the use of the LONGDESC element!

The description of the procedure current strongly implies that every IMG requires a LONGDESC attribute, which is not correct.

This should to be contrasted with the ALT attribute, which is required for every IMG element, as per HTML/4.0 and XHTML/1.0 standards.  But oddly enough, the description of the procedure for technique H37 only says "Check that each img element which conveys meaning contains an alt attribute", which is also incorrect - it should say

"Check that every img element contains an alt attribute.  For img elements which convey mening, check that the attribute value is not blank".


________________________________
From: Loretta Guarino Reid [lorettaguarino@google.com]
Sent: Tuesday, 2 December 2008 10:16 AM
To: Dylan Nicholson
Cc: public-comments-wcag20@w3.org
Subject: Re: Technique H45 procedure description incomplete

Any image *that uses this technique* must pass the check. However, different images, even on the same page, may use different techniques to meet the success criterion.

On Mon, Dec 1, 2008 at 3:13 PM, Dylan Nicholson <d.nicholson@hisoftware.com<mailto:d.nicholson@hisoftware.com>> wrote:
No, this is still problematic because it implies every IMG *should* have a LONGDESC attribute.

In reality, only a tiny percentage of real world IMG elements have LONGDESC attributes.

Having to check that the resource exists does make an automatic check somewhat less efficient, but given that LONGDESC is so rare, it shouldn't be an issue.

At this point I doubt we would bother with implementing an automatic check on the actual content of the page linked to.

________________________________
From: Loretta Guarino Reid [lorettaguarino@google.com<mailto:lorettaguarino@google.com>]
Sent: Tuesday, 2 December 2008 9:55 AM
To: Dylan Nicholson
Cc: public-comments-wcag20@w3.org<mailto:public-comments-wcag20@w3.org>
Subject: Re: Technique H45 procedure description incomplete

On Wed, Nov 12, 2008 at 9:20 PM, Dylan Nicholson <d.nicholson@hisoftware.com<mailto:d.nicholson@hisoftware.com>> wrote:
H45 is described as

Procedure

 1.  Check that a longdesc attribute exists.

 2.  Check that the link in the longdesc attribute is valid

 3.  Check that the long description describes the original non-text content associated with it.

Expected Results

 *   #1 through #3 are all true

But a) it doesn't explain on what elements we are to check for the longdesc attribute - presumably it should be IMG elements only in this case, and not FRAMES and IFRAMEs

b) surely it's not implying that to pass H45 every element that supports longdesc attributes must in fact do so??  That would cause virtually every page on the web to fail immediately, as I don't think I've ever seen a commercial site using LONGDESC - at least, not correctly.

c) what is meant by valid?  That it's a valid url?  Or it actually points to a resource that really exists?  If the former, fine (and a very good idea, seeing I've seen quite a few cases where the LONGDESC attribute actually contains the descriptive text in the value, rather than a URL pointing to where to find the text), but if the latter, then testing this automatically becomes potentially expensive on a large site (well, it would, if anyone actually used LONGDESC).

================================
Response from the Working Group
================================

Thank you, we have updated the test procedure to clarify these issues. See http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-TECHS/H45.html .

Could you let us know by Monday, December 8 whether you are satisfied with our resolution? If that date is not possible, please reply to this message indicating when you will be able to respond.

If we do not hear from you by Monday, December 8, we will assume that you are satisfied with the responses to your comments.

Thanks again for the interest that you have taken in these guidelines.

Loretta Guarino Reid, WCAG WG Co-Chair
Gregg Vanderheiden, WCAG WG Co-Chair
Michael Cooper, WCAG WG Staff Contact