Closed captioning (or subtitling) is the process of displaying text at the bottom of the video player to provide additional or interpretive information to any site viewer who wishes to access it.
Closed captions typically show a transcription of the audio portion of a video as it occurs (either verbatim or in edited form), sometimes including non-speech elements. The XML file will need to be generated by the unit creating the video or by an outside captioning resource.
To install a caption file: