AWC - Accessible Web contents
Visually impaired people must use largely text-based Assistive Technologies
to access the Web. The Web developers must understand how these technologies
operate in order to create compatible contents, which must comply with
the Web Content Accessibility Guidelines (WCAG) of the W3C/WAI (World
Wide Web Consortium/Web Accessibility Initiative).
Some of the Assistive Technologies used are screen readers, magnification
software and Braille display. These technologies offer partial alternatives
to the graphical representation of information, such as graphs, 3D objects,
and images. However, these representations contain a lot of information
which cannot be easily interpreted by screen readers. They are commonly
used by sighted people to present information or exchange ideas more effectively.
Traditionally, to present graphs and images to blind and visually impaired
people, tactile diagrams are used. They can explore the diagrams through
the touch sensation of their fingers. Touch or haptic sense is much more
effective than speech or audio when exploring a graph. It is an active
process in which blind people can have control rather than just being
told by the description through speech. However, through extensive testing
with blind computer users over several years and in different countries,
it is known that presenting graphical images in tactile form to them is
still problematic in the absence of informative annotations, though still
preferable over speech and audio.
As haptic devices become commercially available, research has been conducted
to apply them to the computer-generated graphs. In the previous Framework
programme, research projects such as GRAB has investigated the use of
haptic interfaces to allow blind people to have access to the 3D computer
graphics. Other EU projects such as TIM have tried to present graphs by
using Braille display and tactile boards. Other research projects have
also investigated the use of multimodal interfaces to present 3D virtual
environments to blind people.
Benefits of multimodal representation have been seen from the research
findings of those projects. Therefore, the research effort in this project
will be put on to the use of multimodal representation to make graphs,
3D objects and images accessible.