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This article is part of the series Image and Video Processing for Disability.

Open Access Review Article

Image and Video Processing for Visually Handicapped People

Thierry Pun1*, Patrick Roth1, Guido Bologna2, Konstantinos Moustakas3 and Dimitrios Tzovaras3

Author Affiliations

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

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EURASIP Journal on Image and Video Processing 2007, 2007:025214  doi:10.1155/2007/25214

The electronic version of this article is the complete one and can be found online at: http://jivp.eurasipjournals.com/content/2007/1/025214


Received:30 November 2007
Accepted:31 December 2007
Published:30 March 2008

© 2007 Pun et al.

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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.

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