The Audio Description of Scientific Multimedia
TED.com, Ideas Worth Spreading University of Vic, Spain · 2014
Audio description is an assistive service that allows the blind and visually impaired to access images. It is part of a communication system known as Visual Assistive Discourse (Piety 2003) which uses language for special purposes. The minimal units of such assistive discourse are called Audio Description units (ADUs); they consist of textual chains with linguistic information dependent on visual representation inserted in the message presented as pre-recorded auditory or textual information, and are read by a text-to-speech system. Audio description can be considered a very specific mode of constrained translation, as defined by Mayoral et al. (1998:357), where the target text is subordinate to other requirements, in this case the image. More specifically, it may be seen as a type of intersemiotic constrained translation, since the descriptions, when not accompanied by the document in which the images are included, do not make sense by themselves.