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Re: Investigating the proposed alt attribute recommendations in HTML 5

From: David Poehlman <david.poehlman@handsontechnologeyes.com>
Date: Tue, 11 Sep 2007 16:52:15 -0400
Message-ID: <005601c7f4b5$a3c03890$0601a8c0@HANDS>
To: "Jon Barnett" <jonbarnett@gmail.com>, "Steve Faulkner" <sfaulkner@paciellogroup.com>
Cc: "Henri Sivonen" <hsivonen@iki.fi>, "HTMLWG" <public-html@w3.org>, <wai-xtech@w3.org>

I'd stop at:
alt="Grand Canyon".

----- Original Message ----- 
From: "Jon Barnett" <jonbarnett@gmail.com>
To: "Steve Faulkner" <sfaulkner@paciellogroup.com>
Cc: "Henri Sivonen" <hsivonen@iki.fi>; "HTMLWG" <public-html@w3.org>; 
<wai-xtech@w3.org>
Sent: Tuesday, September 11, 2007 10:17 AM
Subject: Re: Investigating the proposed alt attribute recommendations in 
HTML 5



Steve,

There is a Real Problem we're trying to solve.  Since it's not clear
to me by reading this mess that this problem is understood, I'll try
to state it clearly.

On the web, images are used in various ways.  Sometimes, an image is
iconic and represents text, such as in a menu like this:
[1] <li><a href="..."><img src="home.jpg" alt="Home"></a>
<li><a href="..."><img src="about.jpg" alt="About Us"></a>
<li><a href="..."><img src="store.jpg" alt="Store"></a>
<li><a href="..."><img src="blog.jpg" alt="Blog"></a>

There is no disagreement that alternate text is correct.

Sometimes images are not iconic, but are integral to the meaning of a page:

[2] <img src="grand-canyon.jpg" alt="The grand canyon as viewed from
the east at sunset">

Clearly, that text can't be considered an equivalent for the image -
can a few words replace the grand canyon?  No, the the presence of the
image is important.  A screen reader user needs the presence of the
image announced so that the user knows they're hearing a description
of a picture and not a random sentence out of context.

So, since JAWS can't really tell the difference between [1] and [2],
it sounds from your tests that JAWS announces the presence of the
image.  If it announces the presence of every image [1] gets read as
"Linked Graphic Home Linked Graphic About Us Linked Graphic Store ..."
 Does a blind person really need to be taunted with the presence of 5
or 6 images in a navigational menu?  On the other hand, if JAWS did
NOT announce the presence of an image, [2] would just be read as "The
grand canyon as viewed from the east at sunset" - a single sentence
out of context with no indication that there's an image.

Since @alt is required by HTML4, we often see authors insert text even
when it doesn't belong, such as a list of icons accompanied by text:
[3] <li><a href="..."><img src="home.jpg" alt="Home">Home</a>
<li><a href="..."><img src="about.jpg" alt="About Us">About Us</a>
<li><a href="..."><img src="store.jpg" alt="Store">Store</a>
<li><a href="..."><img src="blog.jpg" alt="Blog">Blog</a>

This, even without announcing the presence of an image, is confusing
when read as "Home Home About Us About Us Store Store Blog Blog".  So,
authors are encourages to simply leave @alt blank:
[4] <li><a href="..."><img src="home.jpg" alt="">Home</a>
<li><a href="..."><img src="about.jpg" alt="">About Us</a>
<li><a href="..."><img src="store.jpg" alt="">Store</a>
<li><a href="..."><img src="blog.jpg" alt="">Blog</a>

That way, a screenreader knows to ignore the image.

But since authors are allowed to just leave @alt blank, they may not
bother describing the grand canyon:
[5] <img src="grand-canyon.jpg" alt="">

Using the logic from [4], the screenreader might think the image can be 
ignored.

That's the problem the draft attempts to solve.  It distinguishes
between [4] (a graphic that can be ignored) and [5] (a meaningful
graphic where the author refused to give any helpful text).  My
suggestion earlier in this thread was to use @title to describe a
meaningful image so there is some accessible text without implying
that text is "equivalent" to the image.

So...


On 9/11/07, Steve Faulkner <sfaulkner@paciellogroup.com> wrote:
> 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)

- In which of these cases is the presence of an image announced?  All
of them?  Are there cases where JAWS sometimes does announce the
presence of an image and when it sometimes does not?  Which ones?

- Does JAWS always treat omitted @alt the same as alt=""?  If so, is
that harmful with the current draft, or is it a reasonable
"degredation" from the current draft?  Would it be reasonable for a
future version of JAWS to follow the draft?

If JAWS's current behavior matches the draft (when it announces the
presence of an image vs. when it doesn't), that great!  But that's not
the important question to ask.  More importantly: If authors use the
semantics laid out in the draft (by omitting @alt and using other
markup for "important" images), does that have harmful side effects in
JAWS, and can a future version of JAWS follow these semantics?

Alternatively, is there a better way to solve these Real Problems in a
way that degrades gracefully and screen readers can implement?  Two
other suggestions have been @noalt - a new attribute to indicate an
important image, and specific markup using <figure> for all
"important" images.  If so, do these solutions solve these Real
Problems in a way that degrades more gracefully in screen readers,
text browsers, and other browsing situations where images are not
loaded?
Received on Tuesday, 11 September 2007 20:52:24 GMT

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