Multi-dimensional information representation - enabling the visually impaired to access graphical user interfaces and documents.

Derwas, P., 2001. Multi-dimensional information representation - enabling the visually impaired to access graphical user interfaces and documents. PhD, Nottingham Trent University.

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As graphical user interfaces (GUIs) replace text-based interfaces, the computer becomes increasingly accessible to sighted people. But for the visually impaired, this trend causes significant problems. For both types of interface, a screen reading system is required to capture screen information and present it non-visually. For graphical user interfaces, these functions are significantly more difficult than for their text based predecessors. This work addresses the problems and evaluates solutions.

A graphical information access system has been constructed using a continuous process of development and evaluation. The basis for this system is an Off Screen Model maintained using OCR and an Icon Matching recognition engine. On top of this, an interface has been created, enabling the user to access display information via a set of experimental interface features. These features have been designed and developed with continuous input from visually impaired computer users. Qualitative evaluation of their effectiveness has been undertaken throughout the course of the project, and results fed back into the development process.

Input and output techniques have been investigated, including use of the mouse as an additional input device, and non-speech sounds to supplement spoken output. The presentation of spatial information, to provide context as well as content, has been a fundamental aspect of the work. User response to this approach and the implemented methods is described. This work draws from the fields of human factors and psychology in the construction of a usable interface, and from research into non-visual display techniques and sound technology in the addition of access features. Comparisons with both research-based and commercial screen reading systems are drawn, and the benefits of the approach taken in representing graphical information described. Furthermore, the concepts and methods introduced have been applied to alternative sources of multidimensional information, notably, graphical documents and data tables.

User response suggests that presenting spatial information is a valid approach to take and that further work would be worthwhile. Well chosen sounds to convey information can be faster to impart and less distracting than speech in some situations. Maintaining a balance between speech and sound use is essential in providing an efficient interface, therefore guidelines for deciding how to represent a particular piece of information are developed throughout the work. The work has been evaluated using a number of features embodying the main themes of the project, thereby suggesting possible paths for future work to take. Results suggest that the work undertaken can provide the visually impaired user with a means of accessing multi-dimensional information.

Item Type: Thesis
Creators: Derwas, P.
Date: 2001
ISBN: 9781369314151
Divisions: Schools > School of Science and Technology
Record created by: Jeremy Silvester
Date Added: 25 Sep 2020 12:16
Last Modified: 20 Jul 2023 10:45

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