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Presenter(s)
Shin Saito
Email: shinsa@jp.ibm.com
Kentarou Fukuda
Email: kantarou@jp.ibm.com
Hironobu Takagi
Email: takagih@jp.ibm.com
Chieko Asakawa
Email: chie@jp.ibm.com
User Experience and Accessibility Research
IBM Tokyo Research Laboratory
1623-14 Shimo-tsuruma, Yamato-shi, Kanagawa-ken 242-8502, Japan
This session introduces a disability simulator "aDesigner", which helps Web designers ensure that the Web content they develop is accessible and usable by visually impaired users. This presentation is designed to show the audience the functions of aDesigner and how easily and effectively the Web designers can analyze Web pages and fix the problems to improve accessibility and usability.
Web accessibility means access to the World Wide Web for everyone, including people with disabilities and senior citizens. Ensuring Web accessibility improves the quality of the lives of such people by removing barriers that prevent them from taking part in many important life activities.
Existing accessibility tools
To open the way for people with visual impairments, voice browsers, such as IBM Home Page Reader, were developed. Voice browsers enable visually impaired people to hear the text information from Web pages. However, as Web authors increasingly rely on visual aids such as images, Web pages are becoming more inaccessible. To make the Web accessible, authors' efforts are indispensable. Recent changes in the social environment, such as the implementation of Section 508 in 2001, also call for Web authors to make their pages accessible.
Programs called "accessibility checkers" are used as author-side tools to check whether a Web page is compliant with accessibility guidelines (such as the Web Content Accessibility Guidelines issued by the World Wide Web consortium). Such tools can be used as the first step of Web accessibility, but their effectiveness is limited because accessibility guidelines do not give much consideration to usability. In addition, they have very little ability to evaluate the accessibility and usability of a Web page as displayed by a Web browser, because they just analyze the HTML tags and attributes. For example, most accessibility guidelines require page authors to provide an "ALT attribute" (alternate text) for each of the images. However, providing inappropriate ALT attributes makes the usability worse, not better. Conventional accessibility checkers can detect images without ALT attributes, but they cannot evaluate the appropriateness of the ALT attributes.
The disability simulator aDesigner helps you make sure that the Web content you develop is accessible and usable by visually impaired users and also checks that it complies with accessibility guidelines. By simulating or visualizing Web pages, aDesigner helps you understand how low vision or blind users experience content on a given Web page, and it also performs a checking function for two types of problems: (a) problems such as redundant text or the appropriateness of alternate text and (b) lack of compliance with accessibility guidelines.
A new kind of disability simulator
The tool aDesigner overcomes the limitations of existing accessibility tools by helping Web authors (many of whom are young and have good vision) to learn about the real accessibility issues. It simulates two types of disabilities, low vision and blindness, and automatically detects accessibility and usability problems on a page. You can specify the guidelines that you want aDesigner to apply in its review (Section 508, IBM Corporate Instruction 162, JIS (Japanese Industrial Standards) X 8341-3, and three priority levels of the Web Content Accessibility Guidelines).
In the low vision mode, aDesigner checks for fixed font sizes, insufficient contrast between foreground and background, and inappropriate color contrasts in images, all of which present accessibility problems for users with vision problems. In the blind mode, it checks for excessive reaching times (the amount of time required to reach each element from the top of a page), redundant text, inappropriate ALT text, problems with table tags, and failure to comply with accessibility guidelines. In addition, it evaluates how well structured the Web content is by checking for the existence of headings or skip-links in the page. If there is a "skip to main content" link or a heading for the main content, most users can easily find the content they are looking for.
The findings can be saved as an HTML document consisting of three parts: an overall rating, a simulated view, and a problem list. Each line in the problem list is dynamically linked to its corresponding element on the simulated image (which is also highlighted). This facilitates finding problems mentioned in the report and addressing them.
The tool also provides the target page's overall rating for accessibility and usability. In the low vision mode, it provides an overall rating that is based on the number of the problems and a problem map that indicates the positions of the problems. In the blind mode, it provides an overall page rating that is based on the number of the problems and a radar chart that visually shows the target page's rating in terms of compliance, navigability, and listenability.
About this session:
We will present information about:
• History of accessibility research at IBM
• Examples of the Web accessibility problems for blind or low vision people
• aDesigner - new accessibility compliance checking tool
• Blind mode and low vision mode in aDesigner
aDesigner trial version (for 90 days use) can be downloaded from IBM alphaWorks Web site (http://www.alphaworks.ibm.com/).
The presenters will also give a live demonstration of the two modes of aDesigner using some Web sites.
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