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Re: Redundant alt text??

From: Greg Gay <g.gay@utoronto.ca>
Date: Tue, 17 Nov 1998 16:29:18 -0500
Message-ID: <3651EAAE.AC2C5D93@utoronto.ca>
To: Al Gilman <asgilman@access.digex.net>
CC: w3c-wai-gl@w3.org
Hello Al


> > Listening to alt text and then alternative text
> > links causes confusion.
> >
> > Should it not be one or the other? Preferable text links
>
> Yes, you are hitting on a point where web content, prepared
> according to these guidelines, is still not ideal.  But it still
> needs to be as the guidelines say to work within the limitations
> of HTML.
>

It's not an HTML problem but rather a designer problem. I am not suggesting
that a link be included in the ALT text, though this would be ideal, but
rather a text  link replace the ALT text in a separate link immediately below
the linked image or image map.

Creating an anchor linked from the top of an image map to the text links, as
you suggest, does allow the user to click it and jump to the text links below,
but this is only useful to sighted users, or those with enough scripting
experience to write a script that tells JAWS, for example, to begin reading at
the link immediately following the jumped to anchor tag.


The utility of ALT text in linked images is questionable. Spending a couple
hours with a JAWS user, it became immediately clear that having to listen to
everything twice was a major annoyance to her. She strongly recomended not
including ALT text with linked images and image maps, but rather to include a
text link below without the ALT text, or include the ALT text without the text
links. One or the other, but not both.

In support of using text links, JAWS does not handle ALT text well in
Netscape. It most often reads the URL of linked images, rather than ALT text.
The same goes for image maps. Text links on the otherhand are read as the text
between the href tags rather than its URL. One glitch we noticed with Netscape
and JAWS is that text links are read as URLs when they are in Times Roman, but
read as the linked text when the font is Arial. I have no explanation for this
other than an incompatibility between JAWS and Netscape.  With Internet
Explorer it works somewhat better, reading the ALT text of the linked image,
but the user must still listen to every linked image or image map twice. Text
links are read as the linked text rather than the URL in IE regardless of the
font face.

Since text links are compatible with all browsers and screen readers, they
should be the preferred means of providing alternative descriptions for linked
images.

We currently include both ALT text and text links for  linked images though we
are seriously thinking of eliminating ALT text. The default ALT text of the
image, rather than the image map, points the user to a set of text links
immediately below the map or image. See the SNOW site for an example.

http://snow.utoronto.ca

I strongly recommend that authoring guidelines outline the problems associated
with redundant links and ALT text for linked images and image maps, suggesting
to designers that they include one or the other, but not both, and that for
compatibility purposes text links are preferred over ALT text. One work around
alternative is to place linked images within DIV tags. Screen readers will
ignore DIVs. If text links are included outside images surrounded by DIV tags
the redundancy is avoided for the screen reader user. A LONGDESC of the image
map, if required, will provide the user with a description of what they are
missing if they choose read it.

> One problem is that ALT text mentioning that there are text links
> at the foot of the page is just text, and there is no easy way
> for the screen reader user to find the head of that list of
> links.  This is related to the reasoning that says OBJECT is a
> superior language capability; but OBJECT is snarled in
> implementation inconsistencies from which it may never recover.
>
> If ALT only allowed a fully-formed hyperlink, with both text
> content and jump destination, you could reasonably offer
> navigation to the text links as an alternative to the image map.
> But it ain't like that.  So please document your MAP AREAs.
>
> Try putting together an example with AREA=DEFAULT linking to the
> text-nav panel.  That might be worth a look.
>
> For the "image links" sub-case, the text links at the foot of the
> page lacks the contextual relevance that makes hypertext great.
> The image links appear somewhere in the flow of the page.  Where
> they appear in the page is part of what cues the reader as to why
> the reader might want to jump there.  That is why it is important
> to capture the jump option in text at the point where it arises
> in the flow, and not merely provide _some jump opportunity to the
> same destination_ somewhere else.
>
> Al
>
> -- all quote below
>
> >
> > "http://www.w3.org/WAI/GL/wai-gl-techniques-19980918.html
> > Technique A.1.3.2
> > In addition to providing alt-text, provide redundant textual links. If
> > the A element is used instead of AREA, the author may describe the
> > active regions and provide redundant links at the same time:"
> >
> > Greg Gay
> > Adaptive Technology Resource Centre
> > University of Toronto
> >

Greg Gay
Adaptive Technology Resource Centre
University of Toronto
Received on Tuesday, 17 November 1998 19:37:00 GMT

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