Audio Description
What It Is
Narration added to the soundtrack to describe important visual details that cannot be understood from the main soundtrack alone. Audio description is a means to inform individuals who are blind or who have low vision about visual content essential for comprehension. Audio description of a video provides information about actions, characters, scene changes, on-screen text, and other visual content. Audio description supplements the regular audio track of a program. Audio description is usually added during existing pauses in dialogue. Audio description is also called “video description” and “descriptive narration”.
When to Include It
The process of audio description can be subjective and considered an art form. Understanding when to describe, what to describe, and when not to describe can feel complex, and finding the right balance takes time. Audio description is required when important information is visually shown on the screen that cannot be observed by individuals with limited or no vision.
It’s important to only describe the seen, and not the unseen. The job of the describer is to describe that which is physically observable and crucial to the viewers’ understanding, but not to offer the listener their personal assumptions, interpretations, or conclusions. Audio description should be used when there is information being portrayed solely through visual means that is required for understanding.
For academic videos, the easiest and most cost-effective method is to verbally describe visual material. Explain the purpose of the visual material, and the required amount of additional audio description can be reduced or even eliminated.
When looking at academic videos, the need for further description of displayed visuals is often critical to not only blind and visually-impaired individuals but to the viewing audience as a whole:
Example:
- An instructor’s video includes a diagram
- Instead of saying "You will note the relationships in this diagram," the instructor can say "You will note that item one and item three directly connect to item four but item five only connects to item two."
When Not to Include It
There are several best practices for creating accessible video for blind and low vision users. While following these guidelines can make implementing audio description easier, it can sometimes eliminate the need for adding audio description in post-production. The best practices include verbally covering all displayed visual information, identifying the speaker and speaker changes, explaining any participation by audience members, and taking frequent pauses. One example of how to describe pertinent visual information when giving a lecture is – rather than saying “I’ve drawn lines on the board,” you can say “I am drawing two parallel lines about three inches apart from one another”. If the original recording covers all of the displayed visual information, audio description may not be needed.
Here are some examples:
- A newscaster introduces the station at the beginning of a video and delivers news of the day without any visual support. In this situation, you need not describe since it does not add to the content.
- An animation of cells dividing in their various stages needs to have audio description. Depending on the narrator’s explanation, an audio describer may offer a more detailed and helpful description of what is visually occurring in the video.
- A video explanation of a math equation: Audio description of each step may be needed depending on the detail of the instructor’s verbal explanation.
Resources
If you would like an opinion on whether audio description is needed, contact MTSU’s Director of ADA Compliance, Faculty Instruction Technology Center, or the Center for Educational Media. When you are ready to move forward with audio description, contact MTSU’sCenter for Educational Media for assistance.
The write up is based on a review of materials from the American Council for the Blind, Penn State University, the University of California at Berkeley, and 3 Play Media.