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Re: [html4all] the alt attribute debate

From: Steven Faulkner <faulkner.steve@gmail.com>
Date: Tue, 25 Sep 2007 12:35:48 +0100
Message-ID: <55687cf80709250435s6f2c17acpea0759b8e97c07ef@mail.gmail.com>
To: "Henri Sivonen" <hsivonen@iki.fi>
Cc: "advocate group" <list@html4all.org>, "John Foliot - WATS. ca" <foliot@wats.ca>, "Anne van Kesteren" <annevk@opera.com>, www-archive@w3.org
Hi Henri,

>Yes, I have noticed that.

so why have you continued to only talk about this point solely in reference
to JAWS?

>The point is that no one has so far explained why that behavior
>(which is awful in some situations as you have demonstrated) would be
>the permanent end state of development for AT and not just a
>transient usability bug that is fixable in a handful of
>implementations. For example, VoiceOver plus Safari on Mac OS X 10.4
>do not share this usability bug, which trivially demonstrates that it
>is possible to construct AT that doesn't have the usability bug.

nobody has said that it is the permanent end state, of course it would be
easy to modify what is announced in response to a an image without an alt in
a particluar context.

The issue is not to do so much with what the AT UA can do with an image
without the alt attribute, it is about what the UA cannot do.
It cannot reliably differentiate between an important image without an alt
attribute and an unimportant image. Therefore they generally treat images
without alt attributes the same way that they treat images with alt="", that
is they ignore them.

The argument used to undermine this issue is that the UA can perform
heuristics to classify (critical content, spacer, decorative, functional,
representation of text etc) the images without alt attributes and then
decide what to announce based on their classification. problem being I
suggest is that there is no reliable way to provide this classification.

 So we come back to the point that not specifying anything for an image is a
worst case and will continue to be.
The only way I can see to identify images that are "critical content" but
the author cannot or will not specify an alt text for them, is to provide a
flag for this in the code,

whether it be:

<img src=001 alt="" noalt>
or
<img src=001 noalt>
or
<img src=001 alt=" ">
or
<img src=001 alt="_noalt">
or
<img src=001 alt="" title="something">
or
<img src=001  title="something">

in this way it can be differentiated from the millions of images out there
of all different sorts that the authors simply did not care to provide alts
for.

>(We shouldn't take stuff under /TR/ as holy writ set in stone when
>following it clearly leads to worse usability than doing something
>smarter.)

who does?


>What I'm talking about isn't rocket science as doesn't involve AI-
>complete UAs describing images to people.

neither does what I am proposing.

>That's a good idea. However, I get a feeling that users may not have
>a good grasp of what kind of ideas would be implementable and,
>therefore, eligible to be suggested.

what you are forgetting is that there are AT users who are also programmers
and designers and spec writers etc. who may be able to grasp the complex
possibilities that reside in a head such as your own.


On 24/09/2007, Henri Sivonen <hsivonen@iki.fi> wrote:
>
> On Sep 24, 2007, at 15:54, Steven Faulkner wrote:
>
> > As have written in response to you on a number of occasions it is
> > not simply JAWS that reads out the a filename (if the image is the
> > sole content of a link) in response to no alt it is also the other
> > major screen reader window eyes and for all i know quite a few others.
>
> Yes, I have noticed that.
>
> The point is that no one has so far explained why that behavior
> (which is awful in some situations as you have demonstrated) would be
> the permanent end state of development for AT and not just a
> transient usability bug that is fixable in a handful of
> implementations. For example, VoiceOver plus Safari on Mac OS X 10.4
> do not share this usability bug, which trivially demonstrates that it
> is possible to construct AT that doesn't have the usability bug.
>
> On the other hand, there being images without human-authored alt text
> seems to be permanent badness instead of a transient problem. It is a
> problem that has been there from the beginning of the Web and shows
> no signs of getting solved. Moreover, it is easy to contemplate new
> situations where some satisfaction (for sighted people) can be
> derived from a workflow (keyboardless camera that uploads to Web
> immediately) that leaves no realistic opportunity for writing
> alternative text. (When there's some satisfaction to be had for a
> notable group of people, people will want to do it, which is why I
> wouldn't expect people to refrain from such workflows for
> accessibility considerations.)
>
> > and these AT are following UAAG: http://www.w3.org/TR/UAAG10-TECHS/
> > guidelines.html#tech-missing-alt
>
> I'm aware of that guideline. I also posit that the guideline taken as-
> is is bad, because there are a lot of real file names out there that
> lead to awful usability when read out load. At minimum, AT should
> check that the filename to be read has some minimal traits of
> readability in the language of the speech synthetizer.
>
> (We shouldn't take stuff under /TR/ as holy writ set in stone when
> following it clearly leads to worse usability than doing something
> smarter.)
>
> > This premise has not been sufficiently tested (actually to my
> > knwoledge, no testing that has been published has been done by
> > proponents of the alt change, so this premise is based on
> > supposition),
>
> That's because it seems so clear to a software developer like me that
> AT software could relatively easily be written to surpass bogus alt
> text in quality. That's why I'd be interested in hearing why AT
> couldn't be improved as suggested below.
>
> (Relative ease above is relative to the ease of making content
> providers abandon the kind of workflows where human-written alt text
> is not one of the products of the workflow.)
>
> > but as my initial testing results revealed much of what you call
> > bogus alt text on images can actually provide some useful
> > information about the image.
>
> Examples of what *I* call bogus alt text are:
> ""
> "image"
> "photo"
> "DSC5413.jpg"
> "IMG8329"
>
> "" has the problem of colliding with the way of indicating that the
> presence of the image should be suppressed from non-visual rendering
> entirely.
>
> "image" and "photo" as part of content are worse than "image" or
> "photo" as AT-generated speech, because they take
> away the opportunities for AT to improve and innovate on how to
> effectively communicate the presence of an image without proper
> alternative text. Examples of what AT could do above the baseline are
> saying "image" or "photo" in the chrome voice instead of the content
> voice (when the AT has different voices for chrome and content) and
> using a audio que that plays faster than those words in the content
> voice.
>
> "DSC5413.jpg" and "IMG8329" are worse than e.g. "image" or "photo"
> said in the chrome voice, because they take a relatively long time to
> read, tell nothing about the image except that it probably came from
> a digital camera and *if* you are able to memorize the numbers as you
> go (a big "if"), you may be able to distinguish images from each
> other as you navigate around.
>
> What I'm talking about isn't rocket science as doesn't involve AI-
> complete UAs describing images to people.
>
> > What needs to be done is more research and hey lets do something
> > novel, lets go and ask the users what they find useful.
>
> That's a good idea. However, I get a feeling that users may not have
> a good grasp of what kind of ideas would be implementable and,
> therefore, eligible to be suggested.
>
> --
> 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, 25 September 2007 11:36:04 UTC

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