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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]

From: Loretta Guarino Reid <lorettaguarino@google.com>
Date: Thu, 28 Nov 2013 16:45:58 +0000
Message-ID: <CAHu5OWYushZh_Kf6rOkH=Vu+ycNw1T01TPf527a2h3up+Rc-eQ@mail.gmail.com>
To: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Cc: Steve Faulkner <faulkner.steve@gmail.com>, "Schnabel, Stefan" <stefan.schnabel@sap.com>, Michael Cooper <cooper@w3.org>, David MacDonald <david100@sympatico.ca>, Janina Sajka <janina@rednote.net>, HTML Accessibility Task Force <public-html-a11y@w3.org>, WCAG WG <w3c-wai-gl@w3.org>, "public-comments-wcag20@w3.org" <public-comments-wcag20@w3.org>, Gregg Vanderheiden <gv@trace.wisc.edu>, "kirsten@can-adapt.com" <kirsten@can-adapt.com>
On Thu, Nov 28, 2013 at 5:03 AM, Leif Halvard Silli <
xn--mlform-iua@xn--mlform-iua.no> wrote:

> Leif Halvard Silli, Thu, 28 Nov 2013 13:59:30 +0100:
> > Steve Faulkner, Thu, 28 Nov 2013 12:51:05 +0000:
> >> Hi stefan, issue with this is
> >>
> >> SR output: graphic Giraffe grazing on tree branches ... Giraffe grazing
> on
> >> tree branches
> >
> > Stefan has a point. But perhaps your comment in reality shows that
> > Stefan’s example needs an *empty* alt?
> >
> > <img src="../images/giraffe.jpg" aria-labelledby="123" alt="" />
> > <p id="123">Giraffe grazing on tree branches</p>
>
> Hm. Forget it. Wouldn't change anything. But an aria-hidden="true"
> would help:
>
> <img src="../images/giraffe.jpg" aria-labelledby="123" />
> <p aria-hidden="true" id="123">Giraffe grazing on tree branches</p>
>

Adding aria-hidden completely changes this example, which is one where the
image description is already available as *visible* text. This is a similar
use case to figure and figcaption.

>
> Leif H Silli
>
>
> >> 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> 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]
> >>> 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;
> 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]
> >>>
> >>> 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
> >>>
>
Received on Thursday, 28 November 2013 17:24:31 UTC

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