Transcript compsoc

Making IT Accessible
Iain Murray
School of Electrical & Computer Engineering
Curtin University of Technology
[email protected]
What will and won’t be covered
 No HTML.
 No Java.
 No Image Editing.
– Animated GIFS, Blinking text etc.
 How people with disabilities access technology.
 Presentation of content for accessibility.
 Why go to the trouble?
 Awareness Issues.
Areas of Concern
 Corporate IT.
– Legalities.
– Productivity.
 Web content accessibility.
– Market size is growing.
– Greater spending power.
 Applications.
 Hardware design considerations.
– Palm, EFTPOS, Ticketing machines etc.
Why?
 Legalities.
– The Sydney Organizing Committee for the
Olympic Games (SOCOG) was successfully
sued for $20,000.
– This has created a precedent.
– Applies to business and Government.
– Estimated only 25% of Australian Web sites
comply with W3C Guidelines (Innes, 2001).
– Australian Disabilities Discrimination Act
1992.
Why?
 19% of the Australian population have disabilities
or functional limitations, which a major cause is
aging (ABS, 1998).
 Includes those.
– born with disabilities.
– whose abilities diminish during their lifetime through
disease, accident or ageing.
 There is a demographic trend toward a growing
elderly population (particularly as the "babyboom"
generation ages).
– Raises the prospect of a large number of consumers
with decreasing abilities.
Disability Discrimination Act
 DDA is administered by the Human rights
and Equal Opportunities Commission
(HREOC).
 Accepts that some differential treatment is
unavoidable.
 Commonwealth Departments and Agencies
must develop action plans.
 Emerging DDA standards on “Electronic
Communication”.
Economic or Humanitarian?
 Should the mainstream design of products
include consideration of people who have
disabilities or are elderly?
– From a humanitarian standpoint.
– This must also be considered in terms of effects
on personnel, curricula and economic
perspectives.
Economic or Humanitarian?
 It is useful to break this complex question into the
following component questions:
– Who is included in the category of "disabled and elderly
persons"?
– How large is the disabled and elderly population?
– Can't the needs of disabled or elderly persons be handled
separately or as exceptions?
– Is it economically and practically feasible to include disabled
and elderly persons in the design process for mass market
products?
– What are the "costs"?
Prevalence of Impairment
All Ages
Over 65
Impairments (vision, hearing, etc.)
20.3%
50.1%
Circulatory conditions
21.7%
63.8%
Respiratory conditions
26.2%
35%
Skin and musculoskeletal conditions
25.5%
57.4%
Other chronic conditions (diabetes, urinary,
other)
27.8%
30.5%
(based on data from National Center for Health Statistics, 1979, as
reported in Czajka, 1984)
Disabled and Elderly Persons
 Can't the Needs of Disabled and Elderly Persons
Be Handled Separately or As Exceptions?
– Many small groups together represent a large portion of
the population.
 Is it both economically and practically feasible to
include disabled and elderly persons in the design
process for mass market products?
– Aging wealthier population.
– OS&H considerations and employee comfort.
– Discrimination suits.
Disabled and Elderly Persons
 What are the costs?
– With web design, negligible.
• If implemented early.
– Hardware and Application designs becoming
cheaper.
• MS speech API (free).
• Speech recorder chips are relatively cheap.
• Voice recognition.
– Standards are available.
• Trace Research EZ Access system.
Access Methods
 For low vision users.
– Screen enlargement.
• Zoomtext, Magic.
– Screen review programs.
• Jaws, Slimware, Artic.
• Two output methods - speech and Braille displays.
– Screen review software must rely on text
output.
Access Methods
 Other mobility difficulties.
– Quadriplegics.
• Morse, Eye tracking, scan boards.
• Emphasis on keyboard/mouse replacement issues.
– Deaf.
• Subtitles, visual alerts, transcription of
conferences/video.
– Many others.
Speech Demonstration
Jaws
jaws keys and demo.doc
Freedom Scientific assistive
technology for blind and visually
impaired computer users.htm
School of Electrical and Computer
Engineering Home page.htm
W3C Guidelines
 Four Parts:
– Techniques for Web Content Accessibility.
• The gateway to other documents.
– Core Techniques for Web Contents Accessibility.
• Discusses the accessibility themes and general techniques that
apply across technologies (e.g. Validation and testing).
– HTML Techniques for Web Content Accessibility.
• Provides examples and strategies for authoring accessible
HTML content.
– CSS Techniques for Web Accessibility.
• Helps authors write cascading style sheets as part of accessible
content design.
Web Content Accessibility
 Accessibility issues.
– Clients may not be able to see, hear, move or process
some types of information easily or at all.
– They may have difficulty reading or comprehending
text.
– They may not be able to use a keyboard or mouse.
– They may have a text-only screen, a small screen or a
slow Internet connection.
– They may be in a situation where their eyes, ears or
hands are busy or interfered with (e.g. driving to work,
working in a loud environment, etc.).
– They may have an early version of a browser, a
different browser entirely or a voice browser.
Checkpoints
 Each checkpoint has a priority level based
on the checkpoint’s impact on accessibility.
 Priority 1.
– A Web content developer must satisfy this
checkpoint. If not, one or more groups will find
it impossible to access information in the
document. Satisfying this checkpoint is a basic
requirement for some groups to be able to use
Web documents.
Checkpoints
 Priority 2.
– A Web content developer should satisfy this
checkpoint. If not, one or more groups will find it
difficult to access information in the document.
Satisfying this checkpoint will remove significant
barriers to accessing Web documents.
 Priority 3.
– A Web content developer may address this checkpoint.
If not, one or more groups will find it somewhat
difficult to access information in the document.
Satisfying this checkpoint will improve access to Web
documents.
– Some checkpoints specify a priority level that may change under certain
(indicated) conditions.
Conformance
 There are three levels of conformance to the
W3C document:
 Conformance Level "A":
– all Priority 1 checkpoints are satisfied.
 Conformance Level "Double-A":
– all Priority 1 and 2 checkpoints are satisfied.
 Conformance Level "Triple-A":
– all Priority 1, 2 and 3 checkpoints are satisfied.
Web Content Accessibility
Guidelines
Guideline 1
Provide equivalent alternatives to auditory
and visual content.
Provide content that, when presented to the
user, conveys essentially the same
function or purpose as auditory or visual
content.
Web Content Accessibility
Guidelines
Guideline 2
Don’t rely on colour alone.
Ensure that text and graphics are
understandable when viewed without colour.
Web Content Accessibility
Guidelines
Guideline 3
Use markup and style sheets and do so
properly.
Markup Documents with the proper structural
elements. Control presentations with style
sheets rather than with presentation elements
and attributes.
Web Content Accessibility
Guidelines
Cascading Style Sheets (CSS) is a
simple mechanism for adding style
(e.g. fonts, colors, spacing) to Web
documents.
<style type="text/css">
body { color: black;
background: white; }
</style>
Web Content Accessibility
Guidelines
MathML is intended to facilitate the
use and re-use of mathematical
and scientific content on the Web,
and for other applications such as
computer algebra systems, print
typesetting, and voice synthesis.
Web Content Accessibility
Guidelines
Guideline 4
Clarify natural language usage.
Use markup that facilitates pronunciation or
interpretation of abbreviated or foreign text.
Web Content Accessibility
Guidelines
Guideline 5
Create tables that transform gracefully.
Ensure that tables have the necessary markup
to be transformed by accessible browsers
and other user agents.
Web Content Accessibility
Guidelines
Guideline 6
Ensure that pages featuring new
technologies transform gracefully.
Ensure that pages are accessible even when
newer technologies are not supported or are
turned off.
Web Content Accessibility
Guidelines
Guideline 7
Ensure user control of time-sensitive
content changes.
Ensure that moving, blinking, scrolling or auto
updating objects or pages may be paused or
stopped.
Web Content Accessibility
Guidelines
Guideline 8
Ensure direct accessibility of embedded
user interfaces.
Ensure that the user interface follows principles
of accessible design, namely deviceindependent access to functionality, keyboard
operability, self voicing etc.
Web Content Accessibility
Guidelines
Guideline 9
Design for device independence.
Use features that enable activation of page
elements via a variety of input devices.
Web Content Accessibility
Guidelines
Web Content Accessibility
Guidelines
Guideline 10
Use interim solutions.
Use interim accessibility solutions so that
assistive technologies and older browsers will
operate correctly.
Web Content Accessibility
Guidelines
Guideline 11
Use W3C technologies and guidelines.
Use W3C technologies (according to
specification) and follow accessibility
guidelines. Where it is not possible to use a
W3C technology, or doing so results in
material that does not transform gracefully,
provide an alternative version of the content
that is accessible.
Web Content Accessibility
Guidelines
Guideline 12
Provide context and orientation
information.
Provide context and orientation information to
help users understand complex pages or
elements.
Web Content Accessibility
Guidelines
Guideline 13
Provide clear navigation mechanisms.
Provide clear and consistent navigation
mechanisms orientation information,
navigation bars, a site map, etc., to increase
the likelihood that a person will find what they
are looking for at a site.
Web Content Accessibility
Guidelines
Guideline 14
Ensure that documents are clear and
simple.
Ensure that documents are clear and simple so
they may be easily understood.
Validation
 Validate accessibility with automatic tools and
human review.
– Bobby is a good example.
– www.cast.org
– Software tools do not address all accessibility issues,
such as the meaningfulness of link text, the
applicability of a text equivalent etc.
– www.abwa.asn.au has links to many automated
validation methods.
– Use validation methods at the earliest stages of
development.
• Accessibility issues identified early are easier to correct or
avoid.
Validation
 Bobby Demo
 bobby.html
 bobby3.2
 bob47867.html
Validation
 The Murray Method:
– 1: Start the screen review software.
– 2: Turn off the screen.
– 3: Disconnect the mouse.
– 4: (Try to) Navigate your site !
 Jaws is available as a free download.
– Supports a software synthesizer.
– Runs for 40 minutes.
Validation Methods
 Use an automated accessibility tool and browser
validation tool.
 Use a text-only browser or emulator.
 Use multiple graphic browsers, with:
–
–
–
–
–
sounds and graphics loaded,
graphics not loaded,
sounds not loaded,
no mouse,
frames, scripts, style sheets, and applets not loaded
 Use several browsers, old and new.
Validation Methods
 Use a self-voicing browser, a screen reader,
magnification software, etc.
 Use spell and grammar checkers.
 Review the document for clarity and simplicity.
– Readability statistics, such as those generated by some
word processors may be useful indicators of clarity and
simplicity.
 Invite people with disabilities to review
documents.
– They are normally more than happy to help out.
Further Information
 W3C Techniques for Web Content
Accessibility Guidelines.
– www.w3c.org/TR/2000/WCAG10-TECHS
 Trace Research and Development Centre.
– www.trace.wisc.edu
 Association for the Blind WA.
– www.abwa.asn .au
Thank You
Any Questions?