Re: User Testing of Accessiblity Features

On Tue, Aug 28, 2007 at 11:34:01AM -0400, Debi Orton wrote:
>
> We (the NYS Forum IT Accessibility Committee) did some work last year that 
> indicated that screen reader users fell into two camps with regard to the 
> usefulness of alt attributes for images.  Some users wanted to know what 
> EVERY image was so that they could be sure they weren't missing 
> information.  Others wanted only meaningful images described.  We proposed 
> an additional attribute (two values only) for the img element to indicate 
> whether the image was informational or just eye candy.

This classification of screen reader users corresponds exactly to the two
divergent views that have been expressed most consistently in mailing list
discussions of this topic.

Rob's image classification proposal, which makes use of an additional
attribute such as @role, would satisfy this need admirably. Note that under
this scheme, whether the image is categorized as decorative is independent of
whether a description is provided:
<img src="image.jpg" role="decorative" alt="short description">
would be the recommended use, where the description may be provided by the
author, or may be obtained by the authoring tool from an image library in
which the image resides.
>
> Using this flag, if supported by AT manufacturers, a user could select 
> whether they wanted everything or just the informational text.

This would also be true with a role-based solution, while adding the
flexibility to permit more than two categories of image to be defined.
>
> Andrew, I think there's some doubt in the W3C workgroups about the 
> necessity for a number of attributes that have traditionally been used to 
> provide contextual information to AT users, such as headers/id in tables, 
> longdesc in img, and there is some question about the extent to which the 
> alt attribute should be used.

I think this is true of an outspoken minority in the HTML working group; so
far, the question of whether this represents the majority viewpoint remains
untested. The decision-making processes within the working group have not been
worked out, and until this happens, and until substantive design issues are
put to the group for decision, we won't know the full spectrum of opinions on
this and other technical topics, or in which direction the group as a whole is
headed.

Equally, there are outspoken opponents within the working group of deprecating
or omitting such features; in general, I count myself among the latter.

Received on Wednesday, 29 August 2007 02:56:38 UTC