- From: Christophe Strobbe <christophe.strobbe@esat.kuleuven.be>
- Date: Tue, 13 Feb 2007 15:55:13 +0100
- To: public-bpwg-comments@w3.org
Hi, Below are a few comments and questions about the working draft [1]. * 3.1 AUTO_REFRESH (partial) and REDIRECTION The draft states: "This test does not determine whether the user is able to opt out of refresh." Is the possibility of opting out going to be covered elsewhere? Using <meta http-equiv="refresh" content="..." /> fails three different success criteria of the Web Content Accessibility Guidelines 2.0 (see failure F40 in "Techniques for WCAG 2.0" [2]). This is because screen readers will start reading from the top of the page again when the page refreshes, thereby taking away control from the user over his interaction with a page. Server-side redirects [3] are preferable, but WCAG 2.0 currently also allows client-side redirects if they have no timeout: see techniques G110 (Using an instant client-side redirect [4]) and H76 (Using meta refresh to create an instant client-side redirect [5]). Note that the if statements for the meta element and the HTTP refresh header are different: one refers to "the current resources's URI", while the second refers to "the current page". Shouldn't the same wording be used in both cases? * 3.4 CONTENT_FORMAT_SUPPORT People are aware of validators for HTML, XHTML and CSS, but how do you check if an image is valid according to GIF89A or JPEG? Do image editors check this or do they just check whether the images are "good enough" for the editor? Could you provide pointers to tools that are reliable "validators" for GIF89A and JPEG? * 3.9 IMAGES_RESIZING and IMAGES_SPECIFY_SIZE This prohibits the definition of image size in style sheets [6]. Is that intentional or an oversight? * 3.14 NON-TEXT_ALTERNATIVES (partial) The draft states: "This test does not determine whether the alternative text is meaningful." Why not? Doesn't a meaningless text alternative defeat the purpose of the alt attribute? Note that the current working draft of WCAG 2.0 requires: "text alternatives serve the same purpose and present the same information as the non-text content. If text alternatives cannot serve the same purpose, then text alternatives at least identify the purpose of the non-text content" (this is just part of success criterion 1.1.1 [7]). * 3.24 TABLES_LAYOUT (partial) The draft states: "This test does not catch all cases where tables are used for layout purposes." I agree. "Techniques for WCAG 2.0" also has a test for layout tables [8]: "Check for layout tables: determine whether the content has a relationship with other content in both its column and its row. If 'no,' the table is a layout table. If 'yes,' the table is a data table." Would that be a better fit? Obviously, the test from WCAG 2.0 cannot be automated. [1] http://www.w3.org/TR/2007/WD-mobileOK-basic10-tests-20070130/ [2] http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#F41 [3] http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#SVR1 [4] http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#G110 [5] http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#H76 [6] http://www.textndata.com/articles/webmaster-world/resizable-images-appears-possible-28181/ ; http://www.bigbaer.com/css_tutorials/css.scale.image.html.tutorial.htm [7] http://www.w3.org/TR/2006/WD-WCAG20-20060427/complete.html#text-equiv-all [8] http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#H39-tests Best regards, Christophe Strobbe -- Christophe Strobbe K.U.Leuven - Departement of Electrical Engineering - Research Group on Document Architectures Kasteelpark Arenberg 10 - 3001 Leuven-Heverlee - BELGIUM tel: +32 16 32 85 51 http://www.docarch.be/ Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
Received on Tuesday, 13 February 2007 14:55:20 UTC