- From: Cynthia Shelly <cyns@microsoft.com>
- Date: Thu, 6 Dec 2001 21:18:32 -0800
- To: "Adam Victor Reed" <areed2@calstatela.edu>, <w3c-wai-gl@w3.org>
This is a good start. I'm looking forward to your document in January. This bit isn't quite accurate <quote> ALT parameter contains text which IS presented whenever the corresponding visual is NOT being accessed, and that is NOT normally presented when the visual IS being acccessed. </quote> In Internet Explorer, when images are presneted, the alt-text is also available as a tool-tip. You will see it if you mouse over the image (there is probably also a keyboard way to get to tool-tips, but I don't know what it is). I'm not sure if Netscape does the same thing. Does anyone know? -----Original Message----- From: Adam Victor Reed [mailto:areed2@calstatela.edu] Sent: Thu 12/6/2001 8:34 PM To: w3c-wai-gl@w3.org Cc: Subject: Foundation for text techniques I am planning to write the techniques document on accessibility text (alt, title and longdesc parameters of tags presenting content that would not be universally accessible without those parameters) over the winter break, so this discussion cames just in time. I am not claiming that my current understanding of the relevant issues is necessarily correct, but if I my understanding diverges either from relevant facts or from the concensus of this group, I need to know it now. So please comment on the following summary: 1. The default (pictorial or animated) content and the ALT text are alternatives: when one is presented, the other isn't. Thus the ALT parameter contains text which IS presented whenever the corresponding visual is NOT being accessed, and that is NOT normally presented when the visual IS being acccessed. Constraint: In common ("visual") browsers, the presentation of the ALT text normally uses the same real-estate that would contain, if the user chose to load images, the corresponding visual. To maximize the likelihood of fitting in the reserved area, the ALT text should be as brief as possible. 2. According to the HTML recommendation, <http://www.w3.org/TR/REC-html40/struct/global.html#adef-title>, the TITLE parameter's function is to "offer advisory information about the element". This means that the TITLE text is an optional addition to whatever content (visual or ALT) is already displayed. The presentation of the TITLE text in the user agent usually depends on user actions, or on user-specified browser options. In visual browsers, the TITLE text is normally available as a "tool tip", that is, as text which pops up when the mouse cursor is positioned over the element area, regardless of whether the element area contains the default element or its ALT text. In non-visual (text, auditory etc) browsers, the presentation of the TITLE text may depend on whether an ALT text string is also available. Such browsers may present the TITLE text automatically if ALT is not found. If ALT text is available, the presentation of TITLE text depends on a user-set option, or on user input. Users of text browsers generally prefer that if ALT and TITLE are both displayed, the TITLE be presented in parentheses after the ALT. (I'd like input from list users on what is preferred by users of auditory and other browsers.) 4. LONGDESC is a separate resource which provides, for users unable to access the visual in full detail, all the information that a user to whom the visual is fully accessible would be able to extract from it if she examined the visual exhaustively. It should be usable not only by users who require ALT, but also by users who can extract casually adequate information but not complete detail from the visual itself. For example, a colored image might convey information equivalent to an adequate ALT even to a color-blind user, but this user then might use the LONGDESC resource for access to details that others could deduce from colors in the image. The LONGDESC resource should be available through a user action, such as a link in a menu displayed when the menu button is depressed over the image in a visual browser. (How do users of auditory browsers prefer to access LONGDESC?) Is the above a reasonable starting point for the techniques document? -- Adam Reed areed2@calstatela.edu Context matters. Seldom does *anything* have only one cause.
Received on Friday, 7 December 2001 00:19:05 UTC