Re: feedback requested on WAI CG Consensus Resolutions on Text alternatives in HTML 5 document

On Aug 17, 2009, at 8:39 AM, Steven Faulkner wrote:

> hi benjamin,
>
> understand where your coming from,
>
> the AT could just as well support a mode where all images are  
> available including those with role="presentation"
> this could be achieved by accessing the HTML DOM rather than the  
> accessibility API's, AT's already do this for h1-h6 and other  
> elements that do not have useful mappings to properties in  
> accessibility API's

For the combination of Safari+VoiceOver, the actual AT (VoiceOver) has  
no direct access to the DOM, and we kind of like it that way. I think  
it would be better to specify things without overconstraining how the  
browser and AT talk to each other to fix up broken content.

Regards,
Maciej


>
>
> regards
> steve
>
> 2009/8/17 Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
> On 17/08/2009 11:38, Steven Faulkner wrote:
> hi benjamin,
> <p>As you can see from the chart below, sales increased in 2008:</p>
> <img alt="" src="chart.png">
>
> from my understaning this does not conform to WCAG 2.0.
>
> That matches my understanding.
>
> But the example wasn't supposed to conform to WCAG 2.0 or even my  
> idea of best practice: it was supposed to be an example of the  
> "variety of authoring practice around 'alt'" that makes simply  
> assuming an "img" with alt="" will never need exposure to AT unsafe.
>
> I think it's generally best for AT to ignore such "img" elements by  
> default (when they aren't needed to help generate labels). But I do  
> think a mode where even these "img" elements are exposed has user  
> value, given the alternative is to make users dig through a DOM  
> Inspector or source code.
>
> Example use-case: Joe is a blind advanced screen reader user putting  
> together a presentation about his company's performance over the  
> past year. He goes to the corporate wiki and finds references to  
> charts for sales in 2008 and profit/loss margins in 2008, but can't  
> find them when reading through the page. He switches to a mode that  
> exposes even images with alt="" and retrieves the charts based on  
> the document sequence.
>
> Like I said originally, this use case is "tendentious". People can  
> take different views about whether it's practical to support.
>
> --
> Benjamin Hawkes-Lewis
>
>
>
> -- 
> with regards
>
> Steve Faulkner
> Technical Director - TPG Europe
> Director - Web Accessibility Tools Consortium
>
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