1
edit
Changes
→Research Notes
= Research Notes =
'''Preliminary notes, Non-prioritized into an argument'''
[http://sweerdenburg.escapening.com/Storage/Research%20Notes%20-%20BTH740%20-%20Steven%20Weerdenburg.pdf PDF (includes hand-written)]
Sydik - Design Accessible Web Sites (273-296)
(SCANNED IMAGES HERE)
Horton - Access by Design
(SCANNED IMAGES HERE)
Reid-Web Accessibility Standard for Evolving Web
WCAG 1 was for static web sites, now dynamic sites are much more common. Much more involving technologies. WCAG 1 was HTML specific though WCAG 2 is technology independent. Subjective definitions of WCAG 1 posed issues for testability.
4 Criteria:
Presentable
Observable
Understandable
Robustness
Descriptive guidelines, not prescriptive
Testable by humans or machines
3 levels: A, AA, AAA based on possibility, applicability, reasonability, limitations imposed and existence of workarounds. Levels build on each other (A must be met to be AA, AA must be met to be AAA).
ALL OF ABOVE ALSO COVERED BY SYDIK
Responsibility is blurred (user agents can supply content to wikis, blogs, etc.).
"Programmatically determined" is language to define when information must be interoperable with assistive technology or other user agent.
Web master must allow for user-submitted content to confirm to WCAG guidelines (text alternatives for user-submitted pictures, etc). This may not be completely acceptable (such as emails), "Partial Conformance" may be granted.
Technology that is used must enable conformance, though conformance is not stated with regards to if technology is inaccessible. "Accessibility-supported" is when accessibility features of a technology are supported by a user agent (browser, screen reader, etc.). Accessible supported web technologies are context dependent (intranet is less strict than internet). Content language is also important.
As web evolves, more and more difficult to find alternative versions with comparable functionality. May also discourage usage of newer technologies for conformance sake. "Graceful degradation" allows for integration of new technologies with fallback to old (HTML5 video -> Flash). Distinction between "used" and "relied upon", page must be usable on platform where technology is not reliable.
Permits multiple forms (video, video /w sign language, video /w hard captions). Captions may be spoken text (subtitles), descriptive audio (captions) or full-text descriptive content (A, AA, AAA respectively).
CAPTCHA alternatives (audio, video) to traditional image. Scripting also changes the nature of a web page, makes it difficult for screen readers to differentiate a div with a bunch of links from a div as an interactive menu. Not so much an issue if keyboard accessible, but still no way to notify screen readers when element has focus or has changed as result of scripting.
Accessible Rich Internet Application (ARIA)
• Modernized, Extension of XHTML
• Defines mechanism for mapping custom UI controls to native OS accessibility frameworks
• Defines "role" attribute for all elements
• "State" and "Property" attributes that can be mapped to accessibility APIS (onMenuOpen, etc)
• Keyboard focus (extends tabindex)
• Notification of changes by defining events
• Limited support (NEED UP TO DATE INFO, ONLY LISTS FF3, "upcoming IE8")
○ IE8 more standards compliant and accessible http://blogs.msdn.com/b/ie/archive/2009/01/16/accessibility-improved-aria-support-in-the-ie8-rc.aspx
○ GoogleReader http://googleblog.blogspot.com/2008/03/aria-for-google-reader-in-praise-of.html
○ Firefox 3.5, 4 ongoing as standard changes
§ http://www.marcozehe.de/2009/06/26/new-accessibility-features-in-firefox-3-5/
§ http://www.marcozehe.de/2010/10/04/new-in-accessibility-in-firefox-4-0/
○ Webkit (Safari, Chrome) http://www.paciellogroup.com/blog/?p=454, http://www.paciellogroup.com/blog/aria-tests/ARIA-Safari-RoleTests280909.html
Large number of policies and legislation world wide in Canada, Japan, US, UK, EU, UN, Australia, etc.
Sloan-Contextual Web Accessibility
*Published in 2006, mostly applicable to WCAG 1
(pg 122) Despite a large amount of work into legislation, authoring tools, assistive technology development and best practice identification. Large lack of awareness despite efforts of the Web Accessibility Initiative (WAI). WAI developed Web Content Accessibility Guidelines (WCAG) and the User Agent Accessibility Guidelines (UAAG) and Authoring Tools Accessibility Guidelines (ATAG).
WCAG places focus on end users to be aware of software that suits their needs (must have a screen reader to utilize screen reader formatted page). Standards-conformant browsers also an issue.
(pg 123) Sometimes a web site may be structured to cater to a specific audience (learning-disabled children) but be difficult for another (normal-functioning adult).
"CONTEXT OF USE":
• User characteristics
• Domain requirements
• Technological requirements
• Performance requirements
Takes into account "holistic approach" by which e-learning is supplemented by physical learning when required (124). "reflects a wider approach to learning and therefore is more likely to be embedded within the development
of learning resources." WIDER APPROACH MAY COVER MORE BASES, BUT IMPLEMENTATION FEASIBILITY? GRACEFUL DEGREDATION POINTED OUT BY REID
(125) Brings mention of Podcasts, Powerpoints, points out medium-dependent issues. Notes transcripts of podcasts not normally provided, thus breaking WCAG. All this is based on educational0centric standpoint, what about other sites? "effectiveness of the accessibility solution depends on the context of use of the Presentation". Situation-dependent
(126) Personal Needs Application profiles identifying needs are being developed (IEEE Learning Objects Metadata, LOM). Identifies many other learning standards such as ISO SC36, IEEE RAMLET
(127) Context-dependent alternatives, focus on user-centric design and satisfying their needs. "there is no single
universal solution. Instead the developer can select relevant guidelines in order to implement a solution which is usable to the target audience, and taking into account any access requirements. Web developers will then be expected to make use of a range of guidelines covering best practices in areas of accessibility, usability and interoperability. So for example a simple Web site may make use of well-established guidelines such as WCAG and
Nielsen’s usability heuristics to develop a simple solution." THIS PRESUMES IMPLEMENTATION KNOWLEDGE (UAAG), POTENTIAL EXCLUSION OF CASUAL USERS, THOUGH BETTER FOR MAJORITY OF AUDIENCE
Kreps - How the Web Continues to Fail People with Disabilities
Standard-adherence is important to screen readers as pointed out by Horton, Reid. This is similar to industrial revolution standardization of nail/screw sizes, though difficulty is analogous to having living-room plays, gym recitals, small theatre productions and grand operas all appear one after another on same stage (pg 2). Mentions though that the artisans who yielded control in Industrial gave up easier than Microsoft has (pg 3), and that W3C publishes "reccommendations" rather than "standards".
Cites browser usage statistics with regards to standards compliance (pg 4), but NEEDS UP TO DATE INFO, DATED 2008 (All below from http://en.wikipedia.org/wiki/Usage_share_of_web_browsers)
• NetApplication (40,000 sites, unique visitors) http://marketshare.hitslink.com/browser-market-share.aspx?qprid=0
• W3Counter (last 15,000 nonunique views) http://www.w3counter.com/globalstats.php
• StatCounter (3,000,000 sites, #hits (not unique)) http://gs.statcounter.com/
○ Can drill by region/country. Huge differences between US and EU
• W3Schools Counter http://www.w3schools.com/browsers/browsers_stats.asp
• StatOwl (USA only) http://www.statowl.com/web_browser_market_share.php
• Wikimedia visitors http://en.wikipedia.org/wiki/Usage_share_of_web_browsers#Wikimedia_.28April_2009_to_present.29
