What is audio description?
Audio description allows people who are blind or vision impaired to have access to your videos. It is a descriptive narration of all the visual elements of a video. Audio description is written and recorded so that it falls in the gaps between dialogue (and other important audio elements).
In Australia, audio description is available on DVDs, in cinemas and theatrical performances and on a small number of online videos. Like captions, audio description may be either 'open' or 'closed'. Open audio description will be heard by anyone who plays the video. Closed audio description can be turned on and off by the viewer.
Audio description and WCAG 2.0
To comply with Web Content Accessibility Guidelines (WCAG 2.0) Level A, full text alternative or audio description must be provided for all pre-recorded audio-video content (Success Criterion 1.2.3). For those who want to meet WCAG 2.0 Level AA, all pre-recorded audio-video must be audio described, replacing the option of a full text alternative that is available at Level A (Success Criterion 1.2.5). If your organisation's implementation strategy for Level AA compliance is to meet Level A before meeting AA, as outlined in the Web Accessibility National Transition Strategy (NTS), you should produce audio description to avoid duplication. At WCAG 2.0 Level AAA, extended audio description is required for pre-recorded audio-video (Success Criterion 1.2.7). There is no requirement under WCAG 2.0 to provide audio description for live audio-video content.
Audio description guidelines
A number of documents containing audio description guidelines are available online.
- The Audio Description Project, an initiative of the American Council of the Blind, has developed a draft set of Guidelines for Audio Description Standards.
- The Described and Captioned Media Program (DCMP), an educational initiative in the US that supplies schools with captioned and audio described videos, has an online Description Key with video samples.
- The UK communications regulator Ofcom has a section on audio description standards in its Code on Television Access Services.
Best practice for creating audio description
The following is a summary of elements generally considered to be essential if audio is to be of acceptable quality.
- The level of description possible will be determined by the soundtrack. Within time constraints, descriptions should include all information which is important to the plot or characterisation — locations, settings, characters, clothing, facial expressions and mannerisms, lighting, colours, etc.
- Descriptions should, as far as possible, coincide with the actions being described
- Descriptions should be written in clear, simple language. Technical terms should be avoided unless the context demands it and if possible explained.
- Descriptions should be in present tense.
- New speakers in a scene should be identified.
- Descriptions should not give any more information than the sighted viewer would have.
- The passage of time between scenes should be indicated.
- Visual elements which are imagined or remembered, or are obviously part of a dream, should be differentiated from 'real' events.
- The description should give a feel for settings but shouldn't overwhelm people with detail.
- Descriptions should be neutral. Interpretive descriptions, value judgments and aesthetic opinions, e.g. "She looks into the distance, thinking of home", should be avoided.
- The source of unidentified sounds and speech should be described (but only when these would be obvious to the sighted viewer).
- Whole sentences should be used where possible when describing action. It is acceptable though to identify characters by just giving their name, or to describe objects or settings in incomplete sentences (e.g. "A lake with a small island in it.")
- The description should not draw attention to itself. The describer should blend in seamlessly with the rest of the audio.
- The term "we see", and cinematic terms like "the camera zooms in…", "a close-up…" should be avoided.
- Racist or offensive terms should never be used, but ethnicity should be noted when it is essential to plot or character.
- The style of the audio description should match the style of the program. For example, it is acceptable to be more colloquial in children's programs.
- Every gap in dialogue does not need to be filled with description. The music and ambience can tell the story too.
- No description is necessary when there is an obvious audio cue such as a phone ringing.
- If a description must fall on either side of a sound, it is better for it to be before the sound than after.
- For subtitled films, the appearance of subtitles should be noted in the first instance then prefixed with "subtitle" or "he says", "she says", etc.
- If it is necessary to describe over a song, important lyrics should be avoided.
- Credits at the beginning and end of a video should be read out.
Creating audio description files
Audio description is still rare on online videos, and no media players support closed audio description. If you want to have your online video audio described, you will need to put up a version with open audio description, or put up two versions: one with audio description and one without it.
If you don't have the capability to create an audio described version of the soundtrack of your video, you can engage a commercial audio description supplier to create it.