Re: alt crazyness (Re: alt and authoring practices)

On May 3, 2008, at 12:23 , Daniel Glazman wrote:

> A conformance checker will never know what precisely is author's  
> intent.

Indeed. But a conformance checker (piece of software) can't check if a  
page is accessible, either.

However, software can help a *person* assess accessibility. I think  
the Image Report feature of does more to help a person  
who wants to make images accessible than HTML 4 validators checking  
merely for alt presence do. (The feature is also pretty discoverable  
for people who don't yet know that they will want to use it.)

> And I don't expect non-visual user agents to implement such image  
> analysis heuristics just because spec authors think they'll do it.

In general, investments in software don't just happen because spec  
authors said so.

This an economic problem: Does the benefit of implementable image  
analysis (and indeed *some* analysis is implementable given what kind  
of signal processing is known today) justify the opportunity cost?  
That is, do AT vendors get a bigger win by doing something else  
instead? Fortunately, image analysis code would likely be relatively  
separate from the other code in a screen reader, so even if AT vendors  
didn't have economic business incentives to ever pull this off,  
there's opportunity for outside economic disruption by contributing  
code to NVDA or Orca without having to tie up core developer time too  

(I don't think the code size is a big deal these days.)

Henri Sivonen

Received on Saturday, 3 May 2008 10:09:30 UTC