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Re: proposal for "null" alt-text (was "Re: A few thoughts...")

From: Marti <marti47@MEDIAONE.NET>
Date: Sat, 20 Nov 1999 09:26:22 -0500
Message-ID: <025901bf3363$389f3500$ea50da18@ne.mediaone.net>
To: <bbailey@clark.net>, <w3c-wai-ig@w3.org>
Cc: "GARETH P PARKINSON" <298gpp@tay.ac.uk>
 Thank you for the clear statements on this issue. From a personal
standpoint I have frequently be annoyed by the use of alt="", I am always
left wondering what the intent was and what I might be missing, on the other
hand I don't really need to be told about every little 'spacer.gif', that
too can be annoying. A system of punctuation marks to indicate the function
of various graphics seems like a great solution but since we seem to have
trouble getting people to use any alt= in many cases, it seems like a bit of
a dream.

> The difference between null and missing ALT text is the real life
behaviors of
> browsers.  In somecases, MISSING alt text is PREFERABLE to null alt text!
> >From the User Agent Accessibility Guidelines (now in "last call" status)
> URL:
> http://www.w3.org/TR/1999/WD-WAI-USERAGENT-19991105/#gl-content-access
> <Q>2.8 When alternative text has been specified explicitly as empty (i.e.,
> empty string), render nothing.</Q>
> This is how Lynx currently behaves, but not pwWebSpeak.  The guidelines
> nothing about what to do about missing alt (and  invalid html, of which
> be one example.  Lynx (and the big two with image loading off) generate
> something like [IMAGE].  This is different behavior than ALT=" " or
> ALT="nbsp;".  The bigger problem is when an image is a link.  With Lynx,
> link normally gets a number, so the following snippets of code are shown
> to the default rendering with Lynx:
> <A HREF="foobar.html"><IMG SRC="foobar.gif"></A>    [1][LINK]
> <A HREF="foobar.html"><IMG SRC="foobar.gif" ALT="Foobar"></A>    [2]Foobar
> <A HREF="foobar.html"><IMG SRC="foobar.gif" ALT=" "></A>    [3]
> <A HREF="foobar.html"><IMG SRC="foobar.gif" ALT=""></A>
> Notice that the last example generates nothing!  If "hidden" links are the
> links on a page, Lynx generates a warning, but otherwise these hidden
links are
> effectively invisible.  (One can list all links on a page, or look at the
> source code, but these are extreme time consuming measures.)
> We have been over this before, and many have made the arguement that
ALT="" is
> frequently appropriate.  I agree that it should be valid html, but I think
> is a point where the WCAG could make a clear unabigious distinction.
> The problem with ALT="" is that it is ambiguous.  You don't know WHY the
> put that in there.  Is he just trying to get his code validated?  Is this
> REALLY just a decorative, content-free graphic?  Does he have something
> text-based browsers?  Is this some kind of spacer image?  Did he just
> IMHO, ALT="" is NEVER prefereable to other choices.
> For decorative graphics, use a single non-alphanumeric character.  There
> ALWAYS a punctuation mark that is closer in meaning (closer than nothing
> anyway) to a "content free" image.
> The burden of repeated links (one big arguement for using ALT="" within <A
> ... /A>) is much less of a problem than the chance of missing content and
> links!
> Bruce Bailey
> > Hi Len,
> > I was wondering what effect placing a null value in the alt tag. Doesn't
> > this result in the same problem as having no alt tags at all, in that
> > user will be prevented from finding out the reason for the image? I
> > assume that in most cases the image has some meaning, and therefore
> > benefit the user if they could have a description of it.
> >
> > I don't doubt that on a very busy interface there might be call to
> > the amount of text (although perhaps the page is overloaded anyway?) ,
> > such decisions should be made with a lot of caution, and only when
> > no other way to simplify the page. Otherwise,it might wrongly encourage
> > designers to use null values on images that would enhance the page.
> >
> > Gareth Parkinson
> >
> > -----Original Message-----
> > From: Leonard R. Kasday <kasday@acm.org>
> > To: Scott Luebking <phoenixl@netcom.com>; <w3c-wai-ig@w3.org>
> > Date: 15 November 1999 16:09
> > Subject: Re: A few thoughts on using dynamic web pages to improve
> >
> > >Hi Scott,
> > >
> > >Thank for the extra example. I just want to check one thing to preempt
> > >misunderstanding.  Even though you offer a page with alternate layout
> > >other changes to make browsing more efficient with screenreaders, you
> > >make the default page "accessible" in the conventional sense, right?
> > >
> > >For example, the default page would still satisfy the web accessibility
> > >guidelines... alt text, table reading order, etc.   It's just that the
> > >alternate page would be more efficient to use.
> > >
> > >As for the details...
> > >
> > >1. It does seem useful to have an alternate layout where the section of
> > >links and references come at the end instead of the beginning.  It
> > >also be useful to have a link at the start of the page to jump to that
> > section
> > >
> > >2. You speak of leaving out decorative images, but why not accomplish
> > >by simply having null alt text?  A ha.
Received on Saturday, 20 November 1999 09:49:42 UTC

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