Accessible Media Concepts

Captions, audio descriptions and transcripts make online media accessible to people with disabilities. This tutorial will demonstrate how to add captions, audio descriptions and transcripts to video and audio clips. Other accessibility approaches, such as the inclusion of foreign-language subtitles, are also described.

• Captions provide a text version of the video’s dialogue, narration, or other spoken words. They are synchronized with the program audio and displayed within the media player. Captions also include text identifying non-speech information, such as music and sound effects.

• Subtitles are a synchronized text version of a media’s audio track, translated into another language.

• Transcripts are a text version of a video’s audio track, containing narration, dialog and non-speech information such as speaker-identification cues. Transcripts can be static or interactive documents. Interactive transcripts can be synchronized with the media: words are highlighted automatically as they are spoken, or users can select words to move to that spot in the video. Transcripts are crucial for users who are deaf-blind, or for any user who relies on braille.

• Audio descriptions are an extra track of narration (audio or text) that conveys information about important visuals, such as body language, changes in scenery and context, charts and diagrams.

What are high-quality captions and audio descriptions?

Hearing viewers find low-quality, incomplete audio content unacceptable. Similarly, captions that are inaccurate or contain spelling and grammatical errors are unacceptable to deaf and hard-of-hearing viewers. Audio descriptions that provide misleading or inaccurate information, or which provide unnecessary detail (e.g., by giving away clues or answers), are of limited use to viewers who are blind or visually impaired.

Why is this important?

Besides providing crucial communication access for viewers who are deaf, hard of hearing, blind, visually impaired or deaf-blind, captions, audio descriptions and transcripts have benefits beyond their original target audiences:

• Captions, descriptions and transcripts can be used to help all viewers, especially those with cognitive disabilities, engage more directly with media, helping to focus attention or to provide comprehension support.
• Captions are useful when teaching children and adults how to read, or to help people learn a foreign language.
• Everyone can use captions in noisy environments such as a bar, an airport lounge, or in any place where it would be inappropriate to turn up the volume.
• Search engines can use captions and transcripts as a way to locate information in media.
• Audio descriptions can reinforce complex visual concepts, which is especially useful for children or adults with learning disabilities.

For a quick overview on determining whether or not captions and audio descriptions are necessary, see the caption/description decision tree.