People with visual impairments, particularly blind people face a lot of difficulties browsing the web with assistive technologies such as screen readers, when websites do not conform to accessibility standards and are thus inaccessible. HTML is the basic language for website design but its ALT attribute on the IMG element does not adequately capture comprehensive image semantics and description in a way that can be accurately interpreted by screen readers, hence blind people do not usually get the complete description of the image. Most of the problems however arise from web designers and developers not including a description of an image or not comprehensively describing these images to people with visual impairments. In this paper, we propose the use of the Image Description Assessment Tool (IDAT), a Java-based tool containing some proposed heuristics for assessing how well an image description matches the real content of the image on the web. The tool also contains a speech interface which can enable a visually impaired individual to listen to the description of an image that has been uploaded unto the system.
Nganji, J.T., Brayshaw, M., and Tompsett, B. (2013). Describing and Assessing Image Descriptions for Visually Impaired Web Users with IDAT, In 3rd International Conference on Intelligent Human Computer Interaction, Springer-Verlag, Lecture Notes in Computer Science, August 2011, reprinted in Advances in Intelligent Systems and Computing, Volume 179, Springer Verlag, 2013, pp 27-37, ISSN: 2194-5357 (Print) 2194-5365 (Online). [Link to article] [Link to PDF]