Re: Investigating the proposed alt attribute recommendations in HTML 5

Hi Henri,

>Great work. Thank you. Based on your testing, it is clear that the
>current state of JAWS is so bad that indeed any generated placeholder
>alt text (even the empty string) is better than omitting it.

thanks, this testing is just a start...

>That behavior is that alt='' suppresses
>the image altogether but the omission of the attribute causes a
>bearable placeholder to be presented so that the user knows that
>there's an image.

The problem with this is that there is no way for the software to know
whether the images presence needs to be announced to the user.
for example in the cases of decorative images or layout images without an
alt attribute how are these to be filtered out from images that contain
"critical content" without an alt attribute. What is clear (to me) is
that using the omission of the alt attribute is not and will not be a
sufficent flag to assitve tech.
Currently something like 30% (not sure of the exact stats) of images on the
web do not have alt attributes, of these how is the assistive tech to
discern which are worthy of announcing to a user and which are to be safely
ignored? One suggestion has been to provide a noalt attribute I am as yet
unsure of the merits of this proposal. Another suggestion would be
to require the alt unless the image has meta data explicitly associated with
it in some other way. I also asked the question on the list (
http://lists.w3.org/Archives/Public/public-html/2007Sep/0150.html)
whether alt="
" (quote space quote) could be used to flag images that should have an alt
text but none is supplied.


I thought it was clear from the information contained in the testing, but
will restate it:
when images are the sole content of a link and it does not have an alt
attribute JAWS looks for a title attribute on the image, if no title is
present then it announces the image src
when images are the sole content of a link and it does not have an alt
attribute Window Eyes looks for a title attribute on the image or parent
element, if no title is present then it announces the image src
For images that are not the sole content of a link then the image is ignored
(presence of image is not announced).

so:

<img scr="poot.jpg"> image is ignored

<img scr="poot.jpg alt=""> image is ignored

<img src="poot.jpg" title="poot"> title is announced

<a href="poot.html"><img scr="poot.jpg"></a> src is announced

<a href="poot.html"><img scr="poot.jpg" title="poot"></a> title  is
announced

<a href="poot.html" title="poot"><img scr="poot.jpg"></a> title is announced
(window eyes) src is announced (JAWS)



>it is clear that the current state of JAWS is so bad
I don't know what you would expect a screen reader to do?
The apparent reasoning (from the spec) behind allowing the alt to be omitted
(in certain circumnstances) is that the image is "critical content" In this
case it is suggested that heuristics be used by the software to provide
information about the image. And that is what it attempts to do.

>When making Web pages today, catering to today's JAWS, which
>apparently has unbearable placeholders, makes sense. It doesn't
>*necessarily* follow, though, that writing the spec to *require* (as
>opposed to *allow*) catering for the flaws of today's version of JAWS
>makes sense considering the entire life span of the spec.

agreed except that we are not just talking about JAWS, we are also talking
about other screen readers such as Window Eyes (a more complete picture will
emerge once further testing is carried out), but simply allowing the alt
attribute to be omitted does not solve the problem, and could conceivably
worsen the problem as authors and authoring tool vendors are sent the
message (via the spec) that the alt is optional.

Anyway thanks for your thoughts Henri.


On 11/09/2007, Henri Sivonen <hsivonen@iki.fi> wrote:
>
> On Aug 29, 2007, at 21:48, Steven Faulkner wrote:
>
> > Investigating the proposed alt attribute recommendations in HTML 5 -
> > http://www.paciellogroup.com/resources/articles/altinhtml5.html
>
> Great work. Thank you. Based on your testing, it is clear that the
> current state of JAWS is so bad that indeed any generated placeholder
> alt text (even the empty string) is better than omitting it.
>
> Back when I advocated for allowing the omission of the alt attribute
> when the markup generator does not have a textual alternative
> available, I based my argument on the behavior of Lynx (at least some
> version with some settings). That behavior is that alt='' suppresses
> the image altogether but the omission of the attribute causes a
> bearable placeholder to be presented so that the user knows that
> there's an image.
>
> When making Web pages today, catering to today's JAWS, which
> apparently has unbearable placeholders, makes sense. It doesn't
> *necessarily* follow, though, that writing the spec to *require* (as
> opposed to *allow*) catering for the flaws of today's version of JAWS
> makes sense considering the entire life span of the spec.
>
> What, in your opinion, is the outlook on JAWS ever getting fixed? (By
> "fixed" I mean to have image place holders that give a better user
> experience than alt="" or alt="image" or page content duplication in
> the case of a non-decorative image.) Should this WG expect that 7
> years from now, the market leader in voice browsing still hasn't
> evolved to have better heuristics to such extent that J. Random Web
> app developer can do better by putting together *some* generated alt
> text (even alt='', alt='image' or duplicating other data already on
> the page)?
>
> (This is not a flame. This is an honest question. I admit that I
> don't understand the competitive landscape of voice browsing. I'm in
> awe that a product behaving like JAWS can be the market leader.)
>
> --
> Henri Sivonen
> hsivonen@iki.fi
> http://hsivonen.iki.fi/
>
>
>


-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

www.paciellogroup.com | www.wat-c.org
Web Accessibility Toolbar -
http://www.paciellogroup.com/resources/wat-ie-about.html

Received on Tuesday, 11 September 2007 10:58:11 UTC