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RE: alt-text authoring guidelines

From: Charles (Chuck) Oppermann <chuckop@MICROSOFT.com>
Date: Thu, 9 Apr 1998 17:09:49 -0700
Message-ID: <E3A3FFB80F5CD1119CED00805FBECA2F03804314@red-msg-55.dns.microsoft.com>
To: w3c-wai-gl@w3.org
My comments:

"Provide alternative text for all images and image maps"
*	The "good test to determine if alt-text is useful is to imagine
reading the document aloud over the telephone" is excellent.
*	Do not require ALT attribute on APPLET.  Use markup within element.

	"Provide a longer description for graphics that present important
information"
*	I really think an example would be useful here.  Show a pie chart,
or a stock graph and then show, ALT, TITLE and the LONGDESC page

	"Provide a description for each link in an image map"
*	#2 showing the usage of the TITLE attribute is very good.

	"Provide descriptive titles for all images used as links"
*	Using the TITLE attribute on the <A> is good, but needs more
explanation as to why the TITLE is with the <A> and not the <IMG>

	"General Recommendation"
*	With LONGDESC, people can use markup effectively.  For example, a
Pie chart can be rendered textually with a table showing each wedge with a
name and value.

	"Invisible images used as spacers"
*	Null ALT text is generally ALT="", where empty ALT text is ALT=" ".
Maybe it's the programmer in me.

	"Future Notes"
*	There has to be a wide range of examples with the actual image and
calling out the rules used.
*	Include a recommendation that CSS allow the rendering of ALT and
TITLE text.  For example the options can be:
*	Show all ALT text (expand the box) when image not shown
*	Do not show ALT text when image not shown
*	Show TITLE instead of ALT when image not shown
*	Draw ALT text as link when <IMG> is within a <A> when image not
shown
*	Render <AREA> ALT text as a list of links within a <MAP> when image
not shown
*	Do not display ToolTip
*	Other options?

This gives http://www.sony.com <http://www.sony.com>  the ability to not
have ALT text clutter the screen while allowing the user a measure of
control via a user-side style sheet.

Charles Oppermann
Program Manager, Active Accessibility, Microsoft Corporation
 <mailto:chuckop@microsoft.com> mailto:chuckop@microsoft.com
<http://microsoft.com/enable/> http://microsoft.com/enable/
"A computer on every desk and in every home, usable by everyone!"

		-----Original Message-----
		From:	Liam Quinn [mailto:liam@htmlhelp.com]
		Sent:	Thursday, April 09, 1998 4:27 PM
		To:	w3c-wai-gl@w3.org
		Subject:	Re: alt-text authoring guidelines

		At 05:23 PM 09/04/98 -0500, Wendy A Chisholm wrote:
		>We have tried to synthesize all of the comments and
discussion about how to
		>author alt-text for use in the Page Authoring guidelines.
Please read
		>http://trace.ie.wisc.edu/kaboodle/html/tests/alt.htm

		LQ::

		For "Images and Image maps" (section 2.1--the first one),
the first
		paragraph is great, but the examples in that section don't
agree with the
		advice.  ALT="XYZ Logo" does not represent the function of
the image; it
		represents a description of the image.  ALT text
representative of the
		function of the image might be "XYZ" or "Welcome to XYZ",
depending on the
		context.

		Section 2.1.1 recommends using ALT for APPLET and INPUT.  I
don't think ALT
		should be used with APPLET since alternate content can be
given more
		effectively as the content of the APPLET element, allowing
full markup
		whereas ALT text is limited to plain text.  With INPUT, it
should be
		clarified that the ALT attribute is only necessary for
<INPUT TYPE=image>.

		Section 2.2 (which should actually be 2.3) reads as follows:

		| To avoid confusion, if an alternative list of links
follows the image
		map, authors should indicate with | the "alt" attribute of
the MAP element
		that there is an alternate list and its location.

		LQ::  There is no ALT attribute on the MAP element.
Substituting "IMG" for
		"MAP", the advice seems to suggest ALT text of the form "See
text links
		below".  Is this really helpful to those not loading images?
If there are
		text links later in the document, the user will get to them.
Saying "See
		text links below" seems like another reminder that the Web
is made for
		people who can see graphics.  (Of course "below" is also a
poor word choice
		on my part since "below" makes no sense aurally; describing
the location in
		a device-independent way is too difficult to bother with, in
my opinion.)

		If text links are provided in addition to an IMG-based image
map, I'd
		suggest using ALT="" to remove the redundant object for
those not loading
		images.  (And now people will say that they want to know
that an image is
		there, and I will say that they're thinking of the Web as a
visual medium
		and hurting accessibility... <g>)

		Section 2.3.2 (on MAPs including A elements) suggests the
use of the TITLE
		attribute of A.  The example basically just repeats the
content of the A
		element in the TITLE attribute, which seems rather
pointless.  If the
		content of the A element were an abbreviated version and the
TITLE
		attribute gave a full title for the linked resource, use of
TITLE would
		make sense, but I don't think that TITLE should be used when
it just
		repeats information that is more easily available elsewhere.
We have to
		avoid unnecessary redundancies so that user agents don't
start assuming
		that the TITLE attribute is not worth presenting.

		Section 2.4 suggests the use of the TITLE attribute on all A
elements that
		contain an IMG.  Good, functional ALT text should accomplish
the same task,
		as in this modified example from 2.4:

		<A href="home.html"><IMG src="logo.gif" alt="XYZ company
home page"
		title="XYZ Logo"></A>

		Note that this provides the necessary information to the
many user agents
		that lack support for the TITLE attribute.  Even if TITLE
were universally
		supported, I think the preceding use of ALT and TITLE is
more sensible.  An
		alternative would be as follows:

		<A href="home.html" title="XYZ company home page"><IMG
src="logo.gif"
		alt="XYZ" title="XYZ Logo"></A>

		Here I've added the TITLE attribute to A since I've used an
abbreviated ALT
		text.

		In the "Guidelines for writing alt-text", it's suggested
that ALT text
		should end with "proper punctuation, such as a colon or
period".  I'm not
		sure if it's the intention or not, but this seems to suggest
that all ALT
		attribute values should end with some form of punctuation.
First off, ALT
		text may be part of a sentence, in which case punctuation
would most often
		be inappropriate.  Secondly, I commonly use <H1><IMG
src="logo.gif"
		alt="XYZ Company"></H1>, without trailing punctuation since
I want it to be
		presented as <H1>XYZ Company</H1> to those not loading
images.  If
		punctuation should be used in my ALT text here, then it
should also be
		recommended for the end of each heading, which doesn't seem
right.

		For the TITLE attribute, I think the best and most natural
way to use it is
		to provide a title for the IMG, A, or whatever element.
Each image could
		have a title if it were on its own ("XYZ Logo", "My Wedding
Photo", and so
		on).  A elements that link to HTML documents would typically
use the linked
		document's TITLE element as the value of the A element's
TITLE attribute,
		though if the A element's content provides an adequate title
this would
		just be redundant.

		For decorative graphics, I think we need to distinguish
between important
		decorative graphics (such as some photographs) and fluff.
Many decorative
		images, such as a small mailbox icon next to someone's
e-mail address,
		would be best marked up with ALT="" since they are of no use
to those not
		loading images.  Decorative photographs (which in many
respects are
		content) could use descriptive ALT text, though I'd suggest
surrounding the
		ALT text with delimiters such as "[" and "]" to ensure that
the ALT text is
		not misunderstood in a given context.  An example of such a
problem is the
		"Photo of a bull in the water canoeing" howler from Alan
Flavell's article
		on ALT text [1].

		For graphical bullets, I don't see any harm in using style
sheets to
		provide a graphical bullet where the graphical bullet
provides no meaning
		(as is the case with Example 2).  In this case, the
non-graphical browser
		would simply render the list item marker as it normally
would, which should
		not be a problem.  The danger is if the graphical bullet is
depended upon
		to provide a meaning; suitable use of the CLASS attribute
could indicate
		the meaning and style sheets (aural, visual, etc.) could
help express it,
		though the author should not depend on any presentation
getting the meaning
		across.

		[1] http://ppewww.ph.gla.ac.uk/%7Eflavell/alt/alt-text.html

		--
		Liam Quinn
		Web Design Group            Enhanced Designs, Web Site
Development
		http://www.htmlhelp.com/    http://enhanced-designs.com/
Received on Thursday, 9 April 1998 20:10:36 GMT

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