What is Audio Description?
Audio Description (AD) is descriptive audio narration of relevant visual elements of a video not represented in the original audio track for the benefit for someone who has vision loss. The AD voice track is written and recorded so that it fits within the gaps between existing dialogue and important audio elements. The final audio description track can be recorded by a voice artist or generated as a synthetic voice.
Types of Audio Description
Standard Audio Description
Standard AD involves adding the spoken description of visual elements in the natural pauses of the video, such as between sections of dialogue and during
the beginning of a scene, so as to keep the video length the same as the
Extended Audio Description
Some videos may not have enough natural pauses and will require extended AD. This involves editing the video to freeze or pause at points throughout the video to add in the spoken description. Extended AD therefore increases the final length of the video.
How is it made?
The first step in producing AD is the creation of the descriptions. The video is given to an Audio Describer to watch and create a script with the descriptions of the video’s visual aspects. The descriptions should include all information which is important to the plot, characterization and purpose of the material. The script includes time codes of the points of the video where the descriptions should be inserted to ensure to not interfere with dialogue and other important audio elements like music and sound effects.
Once the script has been created, it is now time to record the descriptions being said aloud for the AD voice-over track. There are two voice options for Audio Description: Human Voice and Synthetic Voice. Human Voice AD has the descriptions recorded by an Audio Description Voice Artist whereas Synthetic Voice AD is created used a computer-generated voice. People who are blind or have vision loss are often familiar with the sound of computer-generated voices as they often use screen reader technology that reads aloud visual content on their personal devices such as smart phones and computers.
Once the voice-over track has been recorded, the last step is to add it to the video. A video editor will take the audio track with the recorded descriptions and edit them into the video according to the timecodes included in the script. The video will the be re-exported with the AD audio track burnt in.
Check out the videos below to explore the different types of Audio Description using Synthetic and Human Voice.
Standard AD Human Voice
Extended AD Human Voice
Standard AD Synthetic Voice
Extended AD Synthetic Voice
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