- From: Liam Quinn <liam@htmlhelp.com>
- Date: Thu, 09 Apr 1998 19:26:31 -0400
- To: w3c-wai-gl@w3.org
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 19:27:24 UTC