W3C home > Mailing lists > Public > w3c-wai-au@w3.org > April to June 2006

Re: ATAG 2.0 In-Group Checkpoint Review B.2.4 (JR and TB)

From: Jan Richards <jan.richards@utoronto.ca>
Date: Thu, 20 Apr 2006 09:12:44 -0400
Message-ID: <444788CC.5040701@utoronto.ca>
To: Roberto Scano - IWA/HWG <rscano@iwa-italy.org>
CC: "'List (WAI-AUWG)'" <w3c-wai-au@w3.org>

Hi Roberto,

Yes, you're right - WCAG 2.0 identifies two categories where null 
alternatives are relevant "pure decoration" and "visual formatting only".

I think the existing bullet points are ok for the "pure decoration" case 
because it is something a person has to judge and enter for the tool to 
"know". But for the "visual formatting only" case, tools can create 
blank pics etc. on the fly, so they "know" they should have null 
alternatives. What do people think of adding a third source bullet to 
SC1 to handle this:

1. If the authoring tool offers text alternatives for non-text objects,
then the source of the alternatives for each object must be one or more
of the following:
- alternatives previously entered by *authors* for the non-text object 
(e.g. by the same author, or another author on a collaborative system)
- alternatives stored with the non-text object in image databases
- null alternatives for non-text objects that are only used only for 
visual formatting
Text alternatives from other sources, such as generated from the 
non-text object file name, are not acceptable.



Cheers,
Jan



Roberto Scano - IWA/HWG wrote:
> Hi,
> Remember also that an alternative - if the non-text object is decorative -
> could be null.
> 
> 
> 
> -----Original Message-----
> From: w3c-wai-au-request@w3.org [mailto:w3c-wai-au-request@w3.org] On Behalf
> Of Jan Richards
> Sent: Wednesday, April 19, 2006 9:05 PM
> To: List (WAI-AUWG)
> Subject: ATAG 2.0 In-Group Checkpoint Review B.2.4 (JR and TB)
> 
> 
> 
> Hi,
> 
> Here is the update B.2.4 proposal from Jan and Tim. SC1 has received the 
> most work:
> 
> 
> B.2.4 Assist authors to ensure that equivalent alternatives
> for non-text objects are accurate and fit the context. [Priority 1]
> 
> Rationale:
> Improperly generated equivalent alternatives can create accessibility 
> problems and interfere with accessibility checking.
> 
> Success Criteria:
> 
> 1. If the authoring tool offers text alternatives for non-text objects, 
> then the source of the alternatives for each object must be one or more 
> of the following:
> - alternatives previously entered by *authors* for the non-text object (e.g.
> by the same author, or another author on a collaborative system)
> - alternatives stored with the non-text object in image databases Text
> alternatives from other sources, such as generated from the 
> non-text object file name, are not acceptable.
> 
> 2. The tool must allow the author to accept, modify, or reject 
> equivalent alternatives.
> 
> 
> 
> 

-- 
Jan Richards, M.Sc.
User Interface Design Specialist
Adaptive Technology Resource Centre (ATRC)
Faculty of Information Studies
University of Toronto

   Email: jan.richards@utoronto.ca
   Web:   http://jan.atrc.utoronto.ca
   Phone: 416-946-7060
   Fax:   416-971-2896
Received on Thursday, 20 April 2006 13:12:59 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 22 September 2008 15:53:06 GMT