Image and Video Processing for Visually Handicapped People
1 Computer Science Department, University of Geneva, Battelle Campus, 7 Route de Drize, 1227 Carouge (Geneva), Switzerland
2 Computer Science Department, University of Applied Studies (HES-SO), 4 Rue de la Prairie, 1202 Geneva, Switzerland
3 Center for Research and Technology Hellas (ITI/CERTH), Informatics and Telematics Institute, 1st Km Thermi-Panorama Road, P.O. Box 361, 57001 Thermi-Thessaloniki, Greece
EURASIP Journal on Image and Video Processing 2007, 2007:025214 doi:10.1155/2007/25214Published: 30 March 2008
This paper reviews the state of the art in the field of assistive devices for sight-handicapped people. It concentrates in particular on systems that use image and video processing for converting visual data into an alternate rendering modality that will be appropriate for a blind user. Such alternate modalities can be auditory, haptic, or a combination of both. There is thus the need for modality conversion, from the visual modality to another one; this is where image and video processing plays a crucial role. The possible alternate sensory channels are examined with the purpose of using them to present visual information to totally blind persons. Aids that are either already existing or still under development are then presented, where a distinction is made according to the final output channel. Haptic encoding is the most often used by means of either tactile or combined tactile/kinesthetic encoding of the visual data. Auditory encoding may lead to low-cost devices, but there is need to handle high information loss incurred when transforming visual data to auditory one. Despite a higher technical complexity, audio/haptic encoding has the advantage of making use of all available user's sensory channels.