Audio description background paper

Audio description (AD) was developed in the US during the early 1980s. It is the descriptive narration of all the visual elements of a TV program, movie, DVD, performance or other media, giving access for the blind or vision impaired. It may be pre-recorded and delivered as an option for television programs or DVDs, or it may be performed live (e.g. for a theatrical performance). AD for television is generally created using a software program such as the Swift ADept, produced by Softel in the UK. The describer watches the program and creates a timecoded AD script, much like a captioner creates a timecoded caption file. This takes into account gaps in dialogue where descriptions can be inserted, and the number of words that can be comfortably spoken in that time. The same software is used to record the descriptions, with the describer watching the program and speaking into a microphone. Whenever a point in the program is approaching where some description is needed, the software gives a visual cue (typically a moving bar at the bottom of the screen, which tells the describer when a section of description must begin and end). The software records each section of AD as a separate audio file, and while some sections may need to be done more than once, there is usually no need for rehearsal. During recording, the software automatically lowers the soundtrack whenever there is a section of description, however, once the AD is complete, it may be necessary for a sound engineer to 'tweak' individual sections of AD for optimum audibility. This is usually done when producing AD for cinema and DVDs.