What types of closed caption files do video players support?

DO-IT Factsheet #1160

Captions are necessary for people who are deaf and hard of hearing to access the audio portion of video presentations. Captions are either open (part of the video, therefore always visible) or closed (a separate text track, which can typically be turned on or off). Open captions are displayed in all video players. However, in some context there are advantages to closed captions as described in the Knowledge Base article What is the difference between open and closed captioning? [1]. Closed captions come in a variety of different file types, and media players vary as to which file types they support.

The following is a summary of some of the more common closed caption file types used to deliver captions for video on the Web:

For information about how to turn captions on or off in various media players, consult the Knowledge Base article How do I turn on captions and descriptive audio in my media player? [8]. For a general overview of multimedia accessibility, consult the Knowledge Base article How do I make multimedia accessible? [9].