- From: Wendy A Chisholm <wendy@w3.org>
- Date: Tue, 23 Oct 2001 20:29:03 -0400
- To: w3c-wai-gl@w3.org
At last week's meeting, we all took an action to try to figure out what is included in the minimum or not. Here are some thoughts about a minimum set. It's an initial pass so I expect there will be issues and that I have probably missed something, but it at least gives us a place to start. The minimal set consists of things that only the author knows or can provide. The secondary set are things that could be derived using a tool. In other words, as long as the author has infused the markup with as many semantics as possible, then a tool could be used to do some extra processing to increase accessibility. For example, I did not include Checkpoint 3.1 Use consistent presentation in the minimal set since it could be possible for a tool to do this if it knew the schema/vocabulary/semantics the author is using. Some authors will feel that they are the only one who can provide the presentation, such as particular look and feel for branding or what not. Therefore, it would be one checkpoint above and beyond the minimum set - they would make this decision. But, for authors who write good markup and are comfortable letting it transform, then all they need to do is provide good markup (primarily, follow checkpoints 1.3 and 1.5). So, here is a first stab at the minimal set of checkpoints. Some reasoning behind some decisions follows this as well as thoughts for a secondary set and more questions about what to do with final form languages [0 - definition at the end]. · Checkpoint 1.1 Provide a text equivalent for all non-text content. · Checkpoint 1.2 Provide synchronized media equivalents for time-dependent presentations. · Checkpoint 1.3 Use markup or a data model to provide the logical structure of content. · Checkpoint 1.4 Identify the primary natural language of text and text equivalents and all changes in natural language. · Checkpoint 1.5 Separate content and structure from presentation. · Checkpoint 2.5 Use device-independent event handlers. · Checkpoint 3.3 Write as clearly and simply as is appropriate for the content. · Checkpoint 3.4 Supplement text with non-text content. · Checkpoint 3.5 Annotate complex, abbreviated, or unfamiliar information with summaries and definitions. · Checkpoint 4.2 Use technologies according to specification. Why some checkpoints are not included in this list: I did not include 4.1 [1] in this list, b/c what if someone is using a device-specific final form language? Then, they need to do something else. We talked a bit about this at the Protocols and Formats Working Group face-to-face at the beginning of October. We came up with a proposal for language, but I'll submit that later. Right now, I'd like to focus on minimal set rather than wording of checkpoints. Also, device-specific final form languages are part of the reason for not including Checkpoint 4.1 Choose technologies that support the use of these guidelines. As I said, if people choose final form, we need to think about if we think they ought to provide final form for {some set of devices} or provide something in an accessible format (similar to 11.4 in WCAG 1.0 - http://www.w3.org/TR/WCAG10/#alt-pages) I did not include 4.4 [2] because if someone does all of these other things, then 4.4 should be satisfied (I think....). Again, not an issue to get into so much right now perhaps. I *did* include Checkpoint 3.3 Write as clearly and simply as is appropriate for the content since the author should write as clearly and simply as is appropriate, but no simpler. If someone (a user, or teacher, etc) wants to make it simpler or present it in a different language, then tools should exist to do those things. Therefore, the author needs to make it as simple as is appropriate, but tools should exist that can simplify it. For example, if we can translate a document from English to French (http://world.altavista.com/) then we should be able to translate a document from English to symbols or simpler English or .... something. Like summarizer tools, such as Summarizer http://www.copernic.com/products/summarizer/ Therefore, of 21 checkpoints, I would say that 10 are core. I expect developers to scream "too much" and disability advocates to scream "too little." <grin/> With the rest of the checkpoints I propose the following - those things that most tools do not yet do today and therefore good for authors to do, basically level 2: · Checkpoint 2.1 Provide multiple site navigation mechanisms. · Checkpoint 2.2 Provide consistent and predictable responses to user actions. · Checkpoint 2.3 Either give users control of mechanisms that cause extreme changes in context or warn them of pending changes. · Checkpoint 2.4 Either give users control over how long they can interact with content that requires a timed response or give them as much time as possible. · Checkpoint 2.6 Avoid causing the screen to flicker. · Checkpoint 2.7 Handle input errors, such as misspellings. · Checkpoint 3.1 Use consistent presentation. · Checkpoint 4.1 Choose technologies that support the use of these guidelines · Checkpoint 4.3 Design user interfaces compatible with assistive technology. · Checkpoint 4.4 Ensure that content remains usable when technologies that modify default user agent processing or behavior are turned off or not supported. Therefore I've sorted this into the following levels or sets of checkpoints: minimal level - 10 checkpoints secondary level - 21 checkpoints (10 minimal + 11 secondary) intermediate levels that may be described in detail in a conformance claim (e.g. minimal+). conformance for device-specific final form languages - similar to 11.4 of WCAG 1.0. Exception to checkpoint 4.1 or its own set of checkpoints? 4.1 seems to be a meta checkpoint of sorts. Either you choose a language that supports these guidelines (and therefore either conform to the minimal level or the secondary level as described above) or you use a device-specific final form language that you have chosen as well as other device-specific final forms or a form that meets at least minimal level or....?. Thoughts? --wendy [0] final form: usually used when data is being stored in some form and then some presentation is generated for a person. device-specific final form languages are written for a specific device, such as a printer, a speech synthesizer, etc. (also called a "formatting object.") For example, speech synthesis markup language is the "final form" representation to be passed to the speech synthesis engine. http://www.w3.org/TR/speech-synthesis WML is a final form for mobile devices. HTML is a final form for desktop browsers. Therefore, a final form can be accessible, but if it is media specific (such as a speech language) then other final forms in other medias will need to be provided. I think this is a fair definition. Please correct me if I am wrong. [1] Checkpoint 4.1 Choose technologies that support the use of these guidelines. [2] Checkpoint 4.4 Ensure that content remains usable when technologies that modify default user agent processing or behavior are turned off or not supported. -- wendy a chisholm world wide web consortium web accessibility initiative seattle, wa usa /--
Received on Tuesday, 23 October 2001 20:23:39 UTC