RE: Clarification of WCAG intent and meaning of techniques [Re: WCAG considering amending F65 to NOT fail missing ALT text if title or aria-label is present]

Redundant announcement of accessibility related info by AT using heuristics is not concept issue but an AT implementation flaw.

Your answer implies that all AT reacts in this way and this is defined behavior. As I said, there is no unique definition how speech output should be so you cannot really argument using the current state of AT speech output implementations as a normative method.

As a hint "what should be done to support existing things better" this is an entirely another story. If this is the intention of WCAG recommendations then, well, I don't think it will evolve things but keeps the status quo intact instead. The disadvantage of this approach is that it removes the burden from AT vendors to change anything and fix incorrect or weird behavior, so I don't favorite this approach.

Supporting an empty alt will ease the pain but this renders the Giraffe to "decorative" (unfortunately). Using aria-hidden is not reflecting well the purpose of the technique "association of visible text (used as caption for an image) with the image".

Regards
Stefan

From: Steve Faulkner [mailto:faulkner.steve@gmail.com]
Sent: Donnerstag, 28. November 2013 13:51
To: Schnabel, Stefan
Cc: Leif Halvard Silli; Michael Cooper; David MacDonald; Janina Sajka; HTML Accessibility Task Force; WCAG WG; public-comments-wcag20@w3.org; Gregg Vanderheiden; kirsten@can-adapt.com
Subject: Re: Clarification of WCAG intent and meaning of techniques [Re: WCAG considering amending F65 to NOT fail missing ALT text if title or aria-label is present]

Hi stefan, issue with this is
SR output: graphic Giraffe grazing on tree branches ... Giraffe grazing on tree branches

--

Regards

SteveF
HTML 5.1<http://www.w3.org/html/wg/drafts/html/master/>

On 28 November 2013 12:48, Schnabel, Stefan <stefan.schnabel@sap.com<mailto:stefan.schnabel@sap.com>> wrote:
>> So, to replace @alt with an @aria-* attribute, would be to do the
opposite of what the WCAG Robustness principle requires
No.

<img src="../images/giraffe.jpg" aria-labelledby="123"/>
<p id="123">Giraffe grazing on tree branches</p>
is equivalent since even if the image is missing the text describing the image is still there.

- Stefan


-----Original Message-----
From: Leif Halvard Silli [mailto:xn--mlform-iua@målform.no<mailto:xn--mlform-iua@m%C3%A5lform.no>]
Sent: Donnerstag, 28. November 2013 13:31
To: Steve Faulkner
Cc: Schnabel, Stefan; Michael Cooper; David MacDonald; Janina Sajka; HTML Accessibility Task Force; WCAG WG; public-comments-wcag20@w3.org<mailto:public-comments-wcag20@w3.org>; Gregg Vanderheiden; kirsten@can-adapt.com<mailto:kirsten@can-adapt.com>
Subject: Re: Clarification of WCAG intent and meaning of techniques [Re: WCAG considering amending F65 to NOT fail missing ALT text if title or aria-label is present]

Steve Faulkner, Thu, 28 Nov 2013 10:24:29 +0000:
> Hi Stefan, this only works for criteria that are solely contingent upon
> accessibility APIs exposing information to AT.
>
> For the case of alt it has not been agreed that this is the case.
>
> Ramon, for example brought up the case of a low vision user who turns off
> images in the browser because the information in the images is difficult to
> perceive, but the alt text exposed as text by the browser is not. This
> involves no AT.
>
> In this case what is required for all of the suggested alternatives
> aria-label etc is that they are displayed in place of an image when an
> image is not displayed. This is currently not the case. If we can interest
> browser implementers exposing aria-label as text in this case then we have
> a practical alternative to alt.

So, to replace @alt with an @aria-* attribute, would be to do the
opposite of what the WCAG Robustness principle requires:
http://www.w3.org/TR/WCAG20/#robust

Leif H Silli