All videos produced should have captions available. Without captions, those who are deaf, hard of hearing, or cannot hear the audio may have difficulty accessing your content. Videos with large amount of visual-only content may require and audio description track for those with vision impairments to describe the video content.
Captions are text versions of all the dialogue and important audio cues synchronized with a video. When creating captions for your video be sure to use correct spelling and punctuation. You have two types of captioning options available: closed captions or open captions.
If possible, avoid using videos with auto-generated captions. If you must use them, make sure the captions are 100% accurate. Even if the words are correct, auto-generated captions do not have punctuation, can be hard to read, and are missing speaker identification.
In many cases, captioned videos on your topic are available for use. When searching YouTube, add “, CC” after your search terms to filter videos to those with captions available.
For Google searches, type “Advanced Video Search” in the search box on Google’s main page. At the top of the form, fill out the Advanced Video Search fields with your search terms. In the Subtitles field, select “closed captioned only” to narrow the results to those with closed captioning.
Audio Description is narration added to a video’s soundtrack to describe important visual details (i.e. actions, characters, scene changes, on-screen text) that cannot be understood from the main soundtrack alone. It is a means to inform individuals who are blind or who have low vision about visual content essential for comprehension. Audio description is a supplement to the regular audio track of a program usually added during existing pauses in dialogue.
It is important to understand what someone who is blind or has low vision needs to know, including reading any titles or wording on the screen that are not spoken aloud in the soundtrack. Use language that is descriptive, accurate and appropriate. Describe what you see without interpretation or personal comment.
Great example: Apple – Accessibility – Sady (Audio Description)