RE: 7 November 2000 WCAG 2.0 draft available

Hopefully this won't start an unending thread on writing good ALT text...

I want to echo Anne approval of the inclusion of this material.  The ALT
content on the new graphic before checkpoint 1.1 is just great!

Personally, I keep in mind the behavior of Lynx when composing ALT tags.
Lynx renders ALT inline.  If the image is not associated with a link, there
is no indication whatsoever to distinguish body text from ALT text.  (Is
this a bad thing?  If so, what UA checkpoint does this violate?)  Take a
look at URL:
<http://ppewww.ph.gla.ac.uk/~flavell/alt/alt-text.html#howlers>
especially the examples about the "Photo of a bull in the water canoeing"
and "Oldtown University arms Physics Department".

This behavior has influenced many content providers to use full punctuation
or surrounding brackets in ALT content.  Do any of the WAI documents mention
or endorse this practice?

I aim for a middle ground for ALT content -- since often a true "textual
equivalent" is not possible without a longer description.  One of my
cardinal rules is repeat any graphical text in the ALT tag.  Other than
that, sometimes it IS better to say what something is rather than to do an
adequate job of replacing it.  Follows is my attempt at improving the
examples.

Example 1.  A short label:  A right arrow icon is used to link to the next
slide in a slideshow.  The text equivalent (ALT) is the word "next".
Accessibility could also improved by including the title of the next slide
in the TITLE attribute of the link.

Example 2.  A short label and a longer explanation:  A bar chart compares
how many widgets were sold over a period of three months.  The short label
(ALT) says, "Graph of the numbers of widgets sold in June, July, and
August."  The longer explanation (LONGDESC) provides the data presented in
the chart.

Example 3.  A short label and a longer explanation:  An animation shows how
to tie a knot.  The short label says, "Animation showing a rope turning
itself into square knot."  The longer explanation describes the hand
movements needed to tie the knot (if this information was not otherwise
included on the page).  This example assumes that a textual header of "How
to Tie a Knot" was also on the page, and that words did not appear in the
animation.

I thought the inadvertent reference to a "figure 8" could be confusing, so
changed it to a square knot. I would argue that examples 2 and 3 are
actually good instances where "substituting for the graphic" is not nearly
as functional as "saying what's there".  Both are also good examples of
where LONGDESC (or some other robust explanation) is really required.
Photos IMHO also frequently have this quality.  I think there is merit in
techniques that allow colleagues to discuss pages with a shared reference.
(E.g., "I saw that our new home page has a group shot of us customer reps on
it.  How do you think I look?")

 It would probably be illustrative to come up with another example where the
ALT text truly does substitute for the image.

Just my two cents.
-- Bruce Bailey

> -----Original Message-----
> From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org]On
> Behalf Of Anne Pemberton
> Sent: Tuesday, November 07, 2000 10:20 AM
> To: Wendy A Chisholm; w3c-wai-gl@w3.org
> Subject: Re: 7 November 2000 WCAG 2.0 draft available
>
>
> Wendy,
>
>       Checked out the guidelines (well, the first few
> anyway), and your
> experiment in using graphics was well done. It is, honesty,
> the first time
> I have seen a long description link in use.
>
>       The three examples listed are good, but they, too, beg
> to be illustrated.
>
>       Let me nitpick on the first example.
>
>> Example 1. a short label: A right arrow icon is used to link
>> to the next slide in a slideshow. The text equivalent is the
>> title of the next slide.
>
> The text equivalent for the arrow should be the word "next",
> not the title
> of the next slide, unless the title is also presented in the visual
> version. Technically, to be most correct, and most useful,
> the arrow should
> have the word "next" embedded in it as well as associated in the text
> equivalent.
>
>> Example 2. a short label and a longer explanation: A bar
>> chart compares how many widgets were sold in June, July,
>> and August. The short label says, "Numbers of widgets
>> sold in June, July, and August." The longer explanation
>> provides the data presented in the chart.
>
> This should be provided with an example of such a bar chart
> and the short
> label (alt text?) and longer explanation (D-Link?). 
>
>> Example 3. a short label and a longer explanation: An
>> animation shows how to tie a knot. The short label says,
>> "How to tie a figure 8." The longer explanation describes
>> the hand movements needed to tie the knot.
>
> Again, this begs to be illustrated. You may need to change
> the example if
> an animation on tying a knot doesn't exist. The flash animation on the
> www.ikea.com site to put together a bookcase could be used,
> if a shorter
> example can't be found.
>
> Wendy, you've made an excellent start!
>
>                           Anne

Received on Tuesday, 7 November 2000 10:57:07 UTC