- From: Daniel Dardailler <danield@w3.org>
- Date: Tue, 17 Oct 2000 08:27:47 +0200
- To: Wendy A Chisholm <wendy@w3.org>
- cc: w3c-wai-gl@w3.org
I agree with everything you said except for the concluding rewrite of the checkpoint. Instead of > 3.1 When an appropriate markup language exists, use markup rather than > images to convey information. [Priority 2] For example, use MathML to mark > up mathematical equations, and style sheets to format text and control > layout. Also, avoid using images to represent text -- use text and style > sheets instead -- except for logos and stylized navigation buttons used to > create a distinctive look to a site. Since one can create a distinctive look using SVG for most logos found on the Web, the "except for logos" part is not really correct. The real meat is in the supported/unsupported markup bit. I suggest something like 3.1 When an appropriate markup language exists and is adequately supported in tools, use markup rather than pixel-based images to convey information. [Priority 2] Examples of markup languages that can replace use of images include: MathML to mark up mathematical equations, SVG for vector graphics and HTML plus style sheets to format text and control layout. Note the change in wording in the second part of the checkpoint, as I don't want to make the reader believe that MathML or SVG are deemed to be adequately supported. Or maybe this should be changed into a "until user agent" kind of stuff, except it would be a "if user agent". > Hello, > > I have reread this entire thread both on IG and GL. I have given this a > lot of thought. I expect disagreement with my conclusions. > > The question is: Does checkpoint 3.1completely outlaw the use of text in > images. > <blockquote> > 3.1 When an appropriate markup language exists, use markup rather than > images to convey information. [Priority 2] For example, use MathML to mark > up mathematical equations, and style sheets to format text and control > layout. Also, avoid using images to represent text -- use text and style > sheets instead. > </blockquote> > > I have boiled the arguments into the following two positions: > > 1. Checkpoint 3.1 of WCAG 1.0 is open to interpretation because people > believe that adequate support for "an appropriate markup language" does not > exist. CSS and SVG as languages exist, but the support for them does > not. Therefore, it <em>should be</em> possible to use images to create > text effects and as long as those images have alt-text a site can claim > WCAG 1.0 AA Conformance. > > 2. Checkpoint 3.1 of WCAG 1.0 is <em>not</em> open to interpretation > because CSS and SVG exist and it is possible to create text effects in > markup language. Therefore, it <em>should not be</em> possible to use > images to create text effects and claim WCAG 1.0 AA Conformance. The > primary reason for using markup is for the user to control the > presentation, particularly to increase the font size. > > This is a priority 2 checkpoint. People can clearly claim WCAG 1.0 single > A conformance and use text in images. > > Conformance to Double A becomes cloudy when we discuss logos or proprietary > (or rare) fonts. It is possible to create logos in SVG, however SVG is > not widely supported. As 3.1 is worded, "an appropriate markup language" > exists, but the support does not. Therefore, as it is worded non of the > W3C sites can claim higher than single A conformance because we include > logos on the majority of our site. Note that many of those pages currently > claim AAA conformance. Therefore, we can infer that we have been > interpreting this checkpoint to mean that an appropriate markup language > does not exist. > > In Opera it is possible to increase the font size of all text, including > alt-text for images, up to 1000%. It is very easy to turn images on and > off in Opera. One only need press "g" or click on a button on the menu > bar. Therefore, if someone with low vision were using the page with opera > and had difficulty reading the text in an image, they could easily toggle > between seeing the image and reading the "magnified" alt-text. > > With the current state of browsers, I do not believe it is possible to > avoid using text in images. Tools exist that will allow users to magnify > the alt-text of those images. There are also tools that will read text out > loud. > > I believe that many of the pages in the W3C site can continue to claim > Triple A conformance to WCAG 1.0 because the appropriate markup language is > not supported. As Lisa pointed out, our own WCAG conformance logo does not > conform to checkpoint 3.1. Why? Because it is very important to establish > the "brand" of both the W3C and WCAG, same with Bobby, and all other logos. > > By saying that people can not use logos and claim anything higher than a > single A would make the other levels of conformance pointless. > > Therefore, I have to agree that sites may use text in images and claim > Double A conformance. However, we should limit the use of text in images to > only what is necessary for branding. I propose limiting text in images to > logos and navigation buttons. It should not be possible to put an entire > paragraph of text in an image and claim Double A conformance because you > lose the structure of the document. > > The only case that remains that I find difficult to satisfy is the case > that Cynthia pointed out where a company is using images in headings as > part of branding. My concern is that people could claim "branding" for so > many things to avoid converting something to markup. I believe this > example violates another checkpoint, 3.5 Use header elements to convey > document structure and use them according to specification. [Priority 2] > Therefore, someone that wedded to appearance is probably only going to > claim Single A and we should all be satisfied with that. > > I propose we add the following to the errata: > 3.1 When an appropriate markup language exists, use markup rather than > images to convey information. [Priority 2] For example, use MathML to mark > up mathematical equations, and style sheets to format text and control > layout. Also, avoid using images to represent text -- use text and style > sheets instead -- except for logos and stylized navigation buttons used to > create a distinctive look to a site. > > Thoughts? > --wendy > -- > wendy a chisholm > world wide web consortium > web accessibility initiative > madison, wi usa > tel: +1 608 663 6346 > /--
Received on Tuesday, 17 October 2000 02:27:48 UTC