Reproduction device and program

A playback apparatus that plays back video data using basic information for controlling a playback of the video data, from a first recording medium on which the video data and the basic information are recorded, the playback apparatus comprising:

• a non-transitory recording medium;
• an interface into which a second recording medium can be inserted and from which the second recording medium can be removed;
• a detection unit operable to detect that the second recording medium is inserted into the interface;
• and
• a playback control unit operable to control the playback of the video data,
• wherein, when the detection unit detects that the second recording medium is inserted into the interface during the playback of the video data recorded on the first recording medium using the basic information, and when supplementary information for controlling the playback of the video data is recorded on the second recording medium, the playback control unit judges whether the supplementary information is associated with the basic information,
• wherein, when the supplementary information is judged to be associated with the basic information, the playback control unit changes an attribute of the supplementary information to read-only, and performs signature verification on the supplementary information using certificate data recorded on the first recording medium and using signature information recorded on the second recording medium,
• wherein, when the supplementary information is judged to be authentic as a result of the signature verification, after the playback control unit stops the playback of the video data using the basic information, the playback control unit performs control to play back the video data using the basic information on the first recording medium and the supplementary information on the second recording medium,
• wherein the detection unit is stored in the non-transitory recording medium as a detection program, and
• wherein the playback apparatus reads and executes the detection program stored in the non-transitory recording medium.