- From: Charles McCathieNevile <charles@w3.org>
- Date: Mon, 30 Jul 2001 04:13:07 -0400 (EDT)
- To: Jason White <jasonw@ariel.ucs.unimelb.edu.au>
- cc: <w3c-wai-gl@w3.org>
I am satisfied that 3.4 represents an important placeholder, and that unless
we can refine it carefully we should keep it. At the point where we have done
so it may be worth considering it again. I have three checkpoint proposals
which I think go some way to clarfying the requirements in reasonably
checkable ways, as follows:
First I would like to add (again) my proposal from may - originally at
http://lists.w3.org/Archives/Public/w3c-wai-gl/2001AprJun/0452 which reads in
part
<quote>
proposed checkpoint
For any description of a process or of relationships, provide a graphic
equivalent.
Techniques stuff...
1. Use case: A description of how to decide whether someting is conformant to
WCAG
Method: Draw a flowchart
2. Use Case: Describing a network
Method: represent the original in RDF and use an RDF to image service to
generate an image
Example:
A textual explanation (of sorts): http://www.w3.org/TR/SVG-access/#Structured
The RDF is incorporated in the SVG version of the image:
http://www.w3.org/TR/SVG-access/rdfnet.svg
There is a gif/png version too:
http://www.w3.org/TR/SVG-access/wholenetwork
The resulting diagram (generated from the RDF - doesn't matter if the
existing image is there or not):
http://www.w3.org/TR/SVG-access/rdfnetViz.png
3. Use Case: A recipe for cooking a pavlova
Method: provide step by step drawings of a process
4. Use case: A description of how to plait a stockwhip or belt
Method: provide a movie demonstrating how to do the process
5. Use case: A description of how to make a medieval-style tent
Method: Provide illustrations of the key steps
</quote>
Proposed checkpoint:
For any page which has a 'concrete thing' as a primary topic, provide a
graphic illustration of that thing.
'concrete thing' is often what the term 'concrete noun' means in grammar - a
person, an animal, a plant, a product. It can also stand for a class of
concrete things - cats, birds, computers, mountains, hotel rooms.
Success criteria:
1. A person who is familiar with the thing recognises the illustration as a
reference performing a "key topic identifier" function. AND
2. A person who reads the page understands the topic that the picture is
illustrating.
techniques:
* Provide a photo of a person on a page about them.
* Provide a photo of a product on a page about it.
* Provide an outline or stylised drawing of a cat on a page about cats. This
will help to identify that this is not a particular cat, but cats in general.
* Provide a stylised image of a TV for a Television guide.
* Provide a stylised image of a bus or train for a bus or train timetable.
* Use clip art images made for the purpose. (Don't break copyright)
* Use a stylised representation for discussing networks.
* Use a stylised representation of sporting equipment (e.g. a football, a
hockey stick, a bicycle)
Rationale:
This will help a person whose dissablity makes reading difficult to undertand
whether the content of the page is reated to the topic they are intersted in,
and therefore to decide if it is worth the effort of reading the entire page.
Why is this better than existing checkpoints:
Because it identifies success criteria, techniques, and circumstances when it
should be applied.
Proposed checkpoint:
For a page that deals with an organisation or concept for which there is a
well known symbol, include that symbol on the page.
Success criteria: as for preceeding proposal.
Techniques:
* Use a national flag
* Use a corporate logo (beware of copyright/trademark!)
* Use music notation fragments as a symbol for music. (Jonathan Chetwynd has
an example - or I can make one)
Rationale as above.
cheers
Charles McCN
On Mon, 30 Jul 2001, Jason White wrote:
Checkpoint 3.4 currently reads:
"Use multimedia to illustrate concepts."
The corresponding checkpoint in WCAG 1.0 (checkpoint 14.2) read as
follows:
"Supplement text with graphic or auditory presentations where they
will facilitate comprehension of the page."
In order to move this discussion forward, please indicate:
a. Whether you are satisfied with either of the above formulations.
b. If not, please provide a proposal that includes the following
information:
1. Your preferred alternative wording for checkpoint 3.4.
2. Your rationale (why you think your proposal is better, whom it
would benefit, and why you think it would benefit them).
3. Success criteria: what would a web content developer need to
accomplish in order to meet the checkpoint.
Unless those who are interested in this issue start providing concrete
proposals of this kind, I suspect the discussion will continue to
reiterate the disagreements and give rise to the confusions which have
characterised it up to this point.
--
Charles McCathieNevile http://www.w3.org/People/Charles phone: +61 409 134 136
W3C Web Accessibility Initiative http://www.w3.org/WAI fax: +1 617 258 5999
Location: 21 Mitchell street FOOTSCRAY Vic 3011, Australia
(or W3C INRIA, Route des Lucioles, BP 93, 06902 Sophia Antipolis Cedex, France)
Received on Monday, 30 July 2001 04:13:10 UTC