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8.9. Descriptive Audio or Video Description
“Descriptive Audio” “Video Description”
Before we dive in, take a moment to look at a brief video clip from the animation, Frozen (new window).
The terms "Audio Description" and "Description" are also used to name this topic. All 4 terms refer to the verbal depiction of key visual elements in media and live productions not accessible to blind or visually-impaired people. Imagine a TV show, movie, presentation, or live performance with a visual impairment. Hearing the spoken words does not fully convey the crucial information that is expressed visually through gestures, character actions, or scenery. In the Frozen video clip, the limited dialog and sounds conveyed a small portion of the experience. Audio description is needed to convey much of the meaning and the ability to experience the video.
Adding a Second User-Selectable Audio Track
A second user-selectable audio track is the most ideal, but most devices don’t have the capability of merging multiple soundtracks. Just creating two tracks may also be problematic. The description must be timed during or just before the visual content is displayed without talking over the spoken content.
Video with limited speaking portions may be adequately described between speaking portions. The Frozen video used this method. Description was added while it played without notably talking over the dialog or sounds or delaying the playback. It also used a method called "ducking" to lower the main audio track to provide distinct description audio. The volume is restored during the dialog portion.
Video with substantial dialog requires pauses in the playback to provide the description in advance of the portion requiring description. The spoken portion will follow as the video advances. Watch a sample video, My Story: Maria (video with Extended Audio Description), to see this method in action.
In one final example, The Hunger Games with audio description: Katniss hunting (new window), this video clip has no dialog. Without description, a visually impaired user would have no understanding of this portion of the movie. It highlights the need to consider description opportunities. While much of our school and office content is geared toward heavy dialog, there are still huge opportunities to make our content accessible and compliant with 504 standards.
Assessing Description Needs
So does every minute of my video need to be described? Not necessarily. Could you cover the screen and still fully understand what’s going on in the video? If not, it needs some description. Consider these made-up scenes from a nature documentary.
- The narrator says “Look at that!” followed by silence.
- Scene 1 could read, “Look at that man-eating lion! He is ready to pounce as he looks hungrily at the gazelle.”
- The narrator says, “I’ll stand over here while Jim wrestles the anaconda,” followed by the sounds of the snake-wrestling match.
- Scene 2 requires some additional description. How does an anaconda wrestle? Who is winning?
- The narrator says, “I’ll stand over here while Jim wrestles the anaconda,” followed by the sounds of the snake-wrestling match.
- Scene 2 requires some additional description. How does an anaconda wrestle? Who is winning?
Production Improvements
In the previous examples, the decision to add description is made to improve the content that is already developed and published. Like most accessibility concerns, it is much easier to create content with accessibility in mind instead of correcting products at a later time. Using the same examples, look at how the script could change to reduce the need for description in post-production.
- The narrator says “Look at that!” followed by silence.
- Scene 1 could read, “Look at that man-eating lion! He is ready to pounce as he looks hungrily at the gazelle.”
- The narrator says, “I’ll stand over here while Jim wrestles the anaconda,” followed by the sounds of the snake-wrestling match.
- Scene 2 could read, “I’ll stand over here while Jim wrestles the anaconda. He is a big one—over 6 ft long. The snake is wrapped around one of Jim's legs while Jim has both hands wrapped around the snake's neck. Looks like he is in the fight of his life."
Both examples could have more description if needed, but building in more descriptive dialog foundationally brings the whole project much closer for anyone with a visual impairment or someone just listening.
Video Captions and Transcripts
Keep in mind, captions are necessary to make audio content accessible to hearing-impaired people or for users in situations where audio cannot be played. Transcripts should include the text of both the captions and the descriptive audio. Both captions and transcripts are important to make your video more accessible, but the audio description recording should be used in conjunction with these efforts too.