W4A (Edinburgh, May 22 2006)
1. INTRODUCTION
Web Accessibility is important!
- 1999: WCAG 1.0 → many guidelines and regulations
- 2004: JIS X 8341-3, Japanese WCAG (similar to WCAG 2.0)
- Web accessibility remains deficient. WHY?
Web Content and User Agents
- Web authors sometimes cannot make accessible content
if they do not know how user agents render their content.
- Ex: accesskey, alt&title&longdesc, heading elements
2. OBJECTIVES OF THE CURRENT SURVEY
Conformance to UAAG 1.0
- How well Japanese UA conform to UAAG 1.0?
Japanese Baseline
- WCAG 2.0 requires Japanese baseline, accessible technologies in Japan.
- Can we set appropriate baseline in Japan?
Accessibility Responsibility Between Content and UA
- Poor UA requires content authors to provide repair content.
Poor content is not accessible with good UA.
4. RESARCH METHODS
- Test Suite: 400 test files
- Test procedures and evaluation criteria are given
- Conformance to UAAG 1.0 is evaluated
- Modified test files are also used
5. SUBJECT USER AGENTS
- User Agent:
- combination of Web browser and screen reader
- voice browser
Three popular UA and one high capability UA (JAWS) are tested.
- Home Page Reader 3.04 SP3 (Japanese ed.)
- PC-Talker XP Version 3.04
- 95 Reader Version 6.0
- JAWS for Windows Pro. Version 6.2 (Japanese ed.)
All screen readers read Internet Explorer only.
6. SUMMARY OF TEST RESULTS
In the following, test results are assigned into 3 categories:
- Capabilities satisfied by almost all UA
- Capabilities satisfied by none of UA
- Capabilities differing among UA
6.1 Capabilities Satisfied by Almost All UA
- Accesskey attribute. If not key combinations were identical to the short cut key of OS or IE.
- Button function in the form element. However, 95 Reader did not handle the submit-type input button.
- Tabindex. Except that 95 Reader did not use "tabindex".
- Activation of event handlers such as "onchange", "onfocus", and "onblur". Except that 95 Reader sometimes did not activate "onchange".
- Alt attributes of "img" and input elements
- "Title" attribute of "img" element. Except that PC-Talker and 95 Reader did not read "alt" attributes when both "alt" and "title" attributes were specified.
- "Caption" element of table.
6.2 Capabilities Satisfied by None of the UA
- Activation of "ondblclick" event when both "onclick" and "ondblclick" were specified.
- Toggle (stop) animated image.
- Control of multimedia objects embedded in "object" (or "embd") elements.
- Toggle (stop) animated or blinking test.
- Toggle (stop) redirect and refresh. (JAWS could stop refresh in virtual view when configured.)
- Navigation among "th" elements.
- Navigation among "thead", "tbody", and "tfooter". Every user agents read "tfooter" before "tbody" because "tfooter" was written before "tbody" in the HTML.
6.3 Capabilities Differing Among UA
JAWS and HPR > PC-Talker and 95 Reader
- Navigation of heading elements inside the page.
- Reading table with use of structure markups such as "summary" elements, "th" elements, and "scope" attribute.
- Link to anchors in the same page.
- Text search in a page.
- Reading "title" attributes of "abbr" and "acronyms" elements.
- Selection of arbitrary parts of text in a page using a keyboard.
- Customization of reading functions.
7. DISCUSSION
7.1 Conformance to UAAG 1.0
20/48 Priority 1 CP were met by all UA but no UA met the following 12:
- CP 2.4: Allow time-independent interaction
- CP 2.5: Make captions, transcripts, audio descriptions available
- CP 2.6: Respect synchronization cues
- CP 3.2: Toggle audio, video, animated images
- CP 3.3: Toggle animated or blinking text
- CP 3.5: Toggle automatic content retrieval
- CP 4.2: Configure font family
- CP 4.4: Slow multimedia
- CP 4.5: Start, stop, pause, and navigate multimedia
- CP 4.6: Do not obscure captions
- CP 4.8: Independent volume control
- CP 9.4: Restore viewport state history
7.2 Capability Difference
JIS X 8341-3 requires structure markups but PC-Talker and 95 Reader cannot
- navigate through heading elements inside the page.
- read table with use of structure markups.
WCAG 2.0 WD requires navigation but PC-Talker and 95 Reader cannot
- jump to anchors in the same page.
- search text inside the page.
Those UA cannot make use of structure and navigation markups!
7.2 Capability Difference
In addition to that, PC-Talker and 95 Reader cannot
- read list numbers of ordered list elements.
- read "title" attributes of "abbr" and "acronym" elements.
- select arbitrary parts of text in a page using a keyboard.
- customize reading functions.
because MSAA only not use DOM extensively.
- MSAA is standard and easy technology for assistive software
but limited functions to retrieve information from Web content.
- DOM enables an application to retrieve structured content and operate Web content and style.
Other discussions
7.3 Baseline of WCAG 2.0
- Baseline concept is good. But baseline technologies cannot be always accessible.
- Even (X)HTML, must be included in every baselines,
major japanese screen readers cannot use structure markups.
- Capability survey of UA is important to show what part of technology is accessible.
7.5 Accessibility Responsibility Between Content and UA
Authors should use markup to specify the structure of the content and users should use user agents which make use of structure markups.
8. CONCLUDING REMARKS
- No UA fulfilled all Priority 1 CP of UAAG 1.0.
- All UA lacked functions relating to the control of multimedia objects and time-dependent interactions.
- Some lacked functions should be implemented in Windows OS / IE.
- Two kinds of UA in Japan.
- JAWS 6.2 and HPR 3.04 can use structure markups
- 95 Reader 6.0 and PC-Talker 3.04 did not have these functions.
- Content authors should conform to accessibility standards such as WCAG and JIS X 8341-3 and users should use UA that have enough accessibility capabilities.
- Japanese use PC-Talker and 95 Reader more often than JAWS. This hinders Web accessibility in Japan.
