- From: Jason White <jasonw@ariel.ucs.unimelb.edu.au>
- Date: Wed, 1 Aug 2001 15:04:03 +1000
- To: Web Content Guidelines <w3c-wai-gl@w3.org>
Checkpoint 1.1: The term "non-text content" is too broad. Consider, for example, a document instance conforming to Charles' DTD for musical notation. This would arguably count as non-text content, but it shouldn't attract the application of checkpoint 1.1. What is needed, instead, is software for displaying or typesetting the musical notation, playing it via a sound system, converting it into braille, converting it into a spoken rendering, etc., not a "text equivalent" as defined in checkpoint 1.1. Suggestion: either change the definition under checkpoint 1.1 to be exclusive (that is, "non-text content" means exactly the phenomena mentioned in the definition), or simply say "auditory, graphical and multimedia presentations" in the text of the checkpoint. Some of the examples mentioned in the definition (spacers, bullets, graphical buttons) are very specific to an HTML legacy and also redundant: if one says "all images" then this necessarily includes the more specific cases mentioned, which then don't need to be pointed out explicitly in the definition. 1.2 There is no mention of "multimedia" in the text of the checkpoint, yet it is the first term in the subsequent definitions. The term "media equivalent" is confusing and not defined anywhere. I would rewrite as: Synchronize auditory and textual equivalents with multimedia presentations Nowhere, though, does it state that auditory descriptions must be provided; this is left implicit as a result of combining the checkpoints of earlier drafts and really should be a separate checkpoint if we want to keep it; or we could modify checkpoint 1.1 to handle this special case. In the success criteria, the words "all significant" were criticised in the teleconference a few weeks ago as being too strong. I would suggest deleting the "all". One solution to the checkpoint 1.2 problem would be to insert a note under checkpoint 1.1 stating that in the case of multimedia presentations, where the user agent can't render the text equivalent and synchronize it with the presentation (see checkpoint 1.2), then the text equivalent must be provided as an audio description. Checkpoint 1.4: I would generalize to encompass other semantic distinctions such as emphasis, which are not structural and hence not encompassed by checkpoint 1.3. I would include natural language identification as an example. This needs to be developed further. 1.5 The definitions of content, structure and presentation are missing. Also, the use of the term "content" here is problematic, as has previously been remarked. Perhaps it would be better to say: "Separate meaning and structure from presentation". This could also have implications for the inclusion of semantically rich metadata in appropriate cases. Guideline 2: the requirement for "navigation mechanisms" (see my proposal from earlier this week) has disappeared. The requirement to handle input errors has been introduced as a separate checkpoint, which is not unreasonable. Checkpoint 2.2: All of the examples here are visually oriented. We should try to diversify the examples somewhat to include speech dialogues, for instance, taking account of all the work that has been devoted to "voice browsers" in recent years. Checkpoint 3.1: Same comment as per checkpoint 2.2, but even more so in this case--the existing text gives the impression that presentation is inherently visual, which we all know not to be true. Note that there is an incomplete sentence at the end of the success criteria (delete the "and"). Checkpoint 3.2: Again no mention of voice characteristics (prosodic effects etc.), such as those controlled by CSS speech properties. Checkpoint 3.3: it is ungrammatical: substitute "simply" for "simple" in the text of the checkpoint. "that you might expect" should be "than you might expect". Checkpoint 3.4: The definition of "non-text content" here should be the same as in checkpoint 1.1. I would suggest generalising and correcting the definition, then making sure that the same definition is used in both checkpoints. Checkpoint 4.4: This still won't work well in the case of XML document types for which the user agent provides no support by default. Perhaps it should be restricted to technologies which modify the behaviour (styling, interaction etc.) which user agents provide by default: Ensure that content remains usable when technologies that modify default user agent processing or behaviour are turned off or not supported. (This wording could be improved but the concept is clear).
Received on Wednesday, 1 August 2001 01:10:52 UTC