Audio description is not a novelty, but as necessary to a person with visual disabilities as captioning is to a person who is Deaf or hard-of-hearing.
Videos typically communicate information both visually and aurally. People who are blind as well as many people who have low vision cannot access on-screen graphic content if it is presented only visually.
Audio Description (AD) contains descriptive narration of key visual elements that make visual media inclusive. It takes a video and talks you through it by describing elements such as actions, gestures, scene changes, images of text important to understanding, and any other significant visual information. It makes video and multimedia accessible by capturing what is happening on screen into audible descriptions that are incorporated during natural pauses in the sound track. It provides a mental picture of what is happening.
The following is an audio described version of the New Faculty Orientation Video by the Multimedia Hub:
For comparison a closed captioned only version of the New Faculty Orientation video without video descriptions is available on YouTube.
- Self-Driving Car Test: Steve Mahan (Audio Described) - YouTube
- The Hunger Games with audio description YouTube
- Frozen - Trailer with Audio Description - YouTube
- Nosferatu with Audio Description - YouTube
- The Described and Captioned Media Program YouTube Channel
- HTML5 video accessibility and the WebVTT file format - Audio Described - YouTube
- Audiodescribe - audiodescribe.com
While people with visual disabilities benefit most from audio description, everyone can find this information useful to process visual content more easily. AD aids understanding by explaining visual information that even people who are sighted may overlook.
As the W3C Media Accessibility User Requirements state,
Described video provides benefits that reach beyond blind or visually impaired viewers; e.g., students grappling with difficult materials or concepts. Descriptions can be used to give supplemental information about what is on screen—the structure of lengthy mathematical equations or the intricacies of a painting, for example.
Creating Audio Descriptions
The Multimedia Hub is available to assist the UMD community in providing videos inclusive to all.
Methods that exist to add audio descriptions to videos include:
- Building the descriptions into the video's audio track from the onset. With some planning before a video is created, audio description of key visuals can usually be woven into the audio script. This avoids the need to go back later and add a large number of descriptions post production or doing number 2 or 3 below.
- Making a second video. You create a copy of your finished video, delete the audio track, and add a new one, in which the AD of the visual information is integrated with the original audio track. Post both the audio described video and the captioned video. Many video players such as YouTube do not have the ability to turn audio descriptions on and off. Examples of this method:
- Adding an extra audio track that does not modify the video's original audio. With this method, the video has more than one audio track attached to it i.e., original, captions, and AD. The user can choose which one to play. This is only available if the video player you use supports adding extra audio tracks. Most online video and multimedia players do not support extra audio tracks.
YouDescribe is the Smith-Kettlewell Video Description Research and Development Center's experimental platform for adding audio description to YouTube videos. As they state it allows,
volunteer sighted describers to take a YouTube video and create an audio description soundtrack. Choose a video, pause it to insert brief descriptions, and tell us what you see! When viewed with YouDescribe, your voice is inserted into those spots in the video. Be descriptive, be brief, be part of the solution!
Compliance with University Accessibility Standard
Effective January 1, 2014, the W3C Web Content Accessibility Guidelines 2.0 (WCAG), level AA, serve as the Web accessibility standard for the University of Minnesota.
WCAG 1.2.5 Audio Description (Prerecorded) is a Level AA accessibility requirement. It states that Audio description is provided for all prerecorded video content in synchronized media. The Success Criterion further explains,
The intent of this Success Criterion is to provide people who are blind or visually impaired access to the visual information in a synchronized media presentation. The audio description augments the audio portion of the presentation with the information needed when the video portion is not available. During existing pauses in dialogue, audio description provides information about actions, characters, scene changes, and on-screen text that are important and are not described or spoken in the main sound track.
Note 1: For 1.2.3, 1.2.5, and 1.2.7, if all of the information in the video track is already provided in the audio track, no audio description is necessary.
- Audio Description (Prerecorded): Understanding SC 1.2.5
- Web Contrast Accessibility Guidelines (WCAG) Technique G69: Providing an alternative for time based media
- WCAG Technique G78: Providing a second, user-selectable, audio track that includes audio descriptions
- WCAG Technique G58: Placing a link to the alternative for time-based media immediately next to the non-text content
- Standard techniques in audio description - Joe Clark
- 508 Accessible Videos - How to Make Audio Descriptions
- Description Key
- Provide a Second Video Version Complete With Audio Description - Denis Boudreau
- What is Audio Description? - Leonie Watson