All captions must belong to a subtitle. In order to create captions, you must first create a subtitle.
Reference
Find captions
Returns all captions for a given mediacontainer id. This array can have multiple subtitle ids – use filter on the client to disinguish between them! If none found, returns an empty array.
Create Captions
Creates a new caption for a given subtitle. Checks the start and endTime against the original media duration.
Update Captions
Updates a caption
Destroy Captions
Deletes a caption and returns a status 204.