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Re: Screen reader interpretations of images in text (not part of a link)

for

From: Jared Smith
Date: May 7, 2012 1:29PM

On Mon, May 7, 2012 at 12:34 PM, Steve Faulkner wrote:

Thanks for chiming in Steve. I knew if I was wrong that you'd set me straight.

> success or failure techniques are not normative [1]

Of course. Though the intention is that if a page has a failure, it
would rarely be conformant. In this case, assuming HTML5 remains as
is, it seems the failure could simply be updated to not require the
alt attribute if the alternative text is provided elsewhere.

> "In HTML5, the alt attribute is currently optional."
>
> I think it is more correct to say that it may be omitted in one
> circumstance: when a programmatically associated text alternative is
> provided using the figure/figcaption elements. [4]
>
> There are no other circumstances where it may be omitted.

I guess this has changed then. Or maybe I had just misinterpreted it.
This is very good to know and is more restrictive than I had thought.

> There is
> currently a circumstance whereby conformance checking tools may suppress
> errors relating to missing alt , but that does not mean the document is not
> invalid due to its absence.

It really is a double-edged sword. If you flag them as errors, it may
promote accessibility. Or it may simply encourage authors to add null
or bogus alt attribute values (which suggest an image alternative
where none is present) simply to generate valid HTML. Admittedly, this
is the current situation for HTML <5, so I wouldn't really expect
things to change much.

> I provide
>  detail and examples of this and a bridging technique (until
> figure/figcaption is better supported) in section 3.12

To me, it seems that it would be better to omit the alt attribute and
<figcaption> altogether. In the case of unknown alternative text, any
approach that utilizes alt or figcaption suggests that a text
alternative is present, when in fact they do not contain an
alternative at all but instead contain a placeholder for that
alternative. This approach uses the alt attribute for something other
than an alternative, which seems wrong to me. It suggests, "alt and/or
figcaption present the image alternative text, except for when they
don't, so good luck figuring out if they actually present an
alternative or not."

Allowing the absence of the alt attribute altogether could be
absolutely clear - the image is inaccessible and does not have a known
alternative. There's no ambiguity or burden on the user to
differentiate between true alternative text and something else that is
currently in the same place the alternative would go if it were known.
Knowing definitively that something is inaccessible can be quite
useful. AT could try to do something useful with the image.
Additionally, automated accessibility validation tools could easily
flag such images as inaccessible. If the alt and/or figcaption
technique you provided was implemented when the alternative is not
known, there would be no way to automatically differentiate them from
other accessible images.

Please clarify if I am still misunderstanding this.

Jared