- From: Robert Burns <rob@robburns.com>
- Date: Thu, 16 Aug 2007 03:03:10 -0500
- To: Gregory J.Rosmaita <oedipus@hicom.net>
- Cc: Maciej Stachowiak <mjs@apple.com>, Jason White <jason@jasonjgw.net>, public-html@w3.org, wai-xtech@w3.org
- Message-Id: <B344566C-3655-4389-8F32-CCCB00AEC414@robburns.com>
This is example example where Ian hasn't even taken his own advice. He has rightly suggested that we all focus on problems statements and use-cases. The changes he's made to the draft certainly reflect an important problem-statement /use-case. However, the solution fails to benefit from the WG process. Many of the topics slowly developing on the wiki have benefitted form many back and forth threads discussing the topic. Even the issue of different purposes for images has been discussed in a manner similar to that shown in the changes to the draft. On Aug 16, 2007, at 1:35 AM, Gregory J. Rosmaita wrote: > > 3 questions: > > 1. why not raise the issue on public-html? Indeed, some of the discussion have already considered this topic. > 2. why not cross post your concerns/issues to the WHAT WG list > and the w3c-wai-au@w3.org list, which exists precisely to > address authoring tool issues; > > 3. how does leaving alt out entirely when an image is not "purely > decorative" "better" serve someone merely by indicating the > presence of an image? I think a better approach might be to add a new attribute to the | img| element (and maybe the other embedded content elements too). I can't think of a good name for this attribute, but consider something like @embedrel (required) for now (name suggestions welcome). The value of this attribute would reflect the scenarios identified in the recent changes to the draft. missing, icon, decorative, seecontext, seefallback. The value 'missing' would be the default value, unless '@a't had a string (or perhaps some other contingencies for content backwards compatibility ) so not setting either @alt or @embedrel would be considered 'missing'. Considering the scenarios in the draft: • A key part of the content that has no textual alternative (missing; @alt could be left off) This is the default value. Editing UAs, converting UAs, and content management UAs should ensure "missing" is set unless the author inputs a string in length greater tha n into the value of the @alt attribute. • An image in an e-mail or document intended for a specific person who is known to be able to view images (missing) I think the email delivery situation is not really different than HTML delivery so perhaps the same keywords should apply. • Icons: a short phrase or label with an alternative graphical representation (icon) • A purely decorative image that doesn't add any information but is still specific to the surrounding content (decorative). Typically CSS would be the preferred approach for these images. These last two (not the same order as the draft) are the trickiest to capture in a keywords that authors will understand. Perhaps others could come up with better keywords here. The main difference here • A phrase or paragraph with an alternative graphical representation (seefallback; alt required) • A graphical representation of some of the surrounding text (seecontext; alt may be omitted) To set the keyword missing and to leave it off would basically mean the same thing. However by requiring authors to at least set the value of the @embedrel attribute, the conformance checking process would raise awareness of the need to consider alternative text for images and other media. in the future, HTML5 conforming aural browsers could easily help users distinguish between these states for any particular non-text embedded content. Authors could easily set "decorative" or "icon" when adding large numbers of decorative and icon content. A contentious author could recognize the image fit the graphic representation scenario and set the attribute value to 'seecontext'. Conformance checkers could easily tell at least whether the document meets particular criteria. For example, it would be able to tell when @embedrel is missing or set to an invalid value and notify the author. If @embedrel is set to 'missing' or ' This may be a complication, but I think the default values could be handled based on the state of the @alt attribute. I most cases the default would be 'missing'. However, if the element had exactly alt='' the default value could be 'decorative'. The other values would require explicitly setting the value. These defaults would map fairly closely to the current practices (I think but others may have other information). Take care, Rob
Received on Thursday, 16 August 2007 08:03:33 UTC