title: Full-screen magnification for windows using DirectX Overlays.
abstract: This paper presents the basic features of software-based magnifiers used by some visually impaired people to read information from a computer screen. The paper briefly presents two major approaches to full-screen magnification for modern multiple window systems (the paper focuses on Microsoft Windows). This paper describes in detail the architecture and operation of a full-screen magnifier that uses Microsoft DirectX Overlays. This approach leads to a robust magnifier that has a low computational overhead. The magnifier has problems with video cards that use a YUV color model but these problems may be addressed by RGB to YUV translation software--an issue that is still to be investigated. The magnifier also has problems when the generic device driver, rather than the manufacturer's device driver, is installed on the system. The paper presents two further strategies for full screen magnification, namely, using multimonitor support and true type fonts for text enlargement.
authors.affiliation: Department of Computation, University of Manchester Institute of Science and Technology (UMIST), Manchester M60 IQD, U.K. p.blenkhorn@co.umist.ac.uk
authors.forename: Paul
authors.initials: P
authors.lastname: Blenkhorn
authors.forename: David Gareth
authors.initials: DG
authors.lastname: Evans
authors.forename: Alex
authors.initials: A
authors.lastname: Baude
mesh_terms: D000465:Algorithms; D003143:Communication Devices for People with Disabilities; D003196:Computer Graphics; D016288:Computer Terminals; D003626:Data Display; D006801:Humans; D019146:Hypermedia; D007089:Image Enhancement / Q000379:methods*; D011381:Programming Languages; D011932:Reading; D012682:Sensory Aids; D012984:Software; D012985:Software Design; D014584:User-Computer Interface; D015354:Vision, Low / Q000534:rehabilitation*