new variant proposal on alt=? issues

Ian wrote:

>   D. Mark the image as being
> critical-but-of-unknown-content.

> I'm aware of three syntax proposals for D
> (omitting alt to indicate this case,
> introducing a new attribute value to indicate
> this case, and introducing a new attribute
> to indicate this case) and one conformance
> definition proposal for handling D.

Instead of introducing a new attribute, this might be a good use of
role, particularly in conjunction with a conformance state like "alt
text needed, otherwise valid."

(Details below are indeed similar to the new attribute value case.)

I understand that alt="" is defined to mean presentational, but it
doesn't mean that in practice, because alt="" is the default output of
so many tools.

Elements with aria role="presentation" are likely to be truly
presentational.  Since there are not currently tools putting this out
by default, we can still require that it not be output by default --
and if the choice is explicit, the human author has taken
responsibility.

When the role is absent or not presentational (e.g., "main",
"secondary", or "note"), then the alt is required for a fully valid
document.  Again, it is clearly the user's responsibility (not the
tool's) to change the role or supply this alt text, and that
responsibility can be reflected in the validation status.

For those rare cases where the alt is truly impossible to create, the
user can choose to publish anyhow -- but the validation checkers will
say there is a problem with the content, rather than the tool.

-jJ

Received on Thursday, 17 April 2008 14:04:49 UTC