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]

Stefan wrote:

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

Why is it a flaw? If you ommit the image (alt=""), the screen reader 
user will not know about it and, for example, he will not be able to 
download the image. If you ommit the paragraph, it can be argued that 
the screen reader user is missing the existence of a structure of image 
+ caption instead of just an image.


> 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”.

In addition, it might cause other issues. For example, a voice 
recognition user might want to select the text to copy it and -maybe- 
the @aria-hidden would prevent it. I'm also not sure if an element that 
is explicitly marked to be hidden to the AT should be read by the same 
AT, even if it is associated through @aria-labelledby.

Regards,
Ramón.


> *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@mĺlform.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

Received on Thursday, 28 November 2013 13:32:25 UTC