Stream generation apparatus, stream generation method, coding apparatus, coding method, recording medium and program thereof

A stream reproduction system comprising:

• (a) a recording medium on which a stream that includes (i) information obtained by coding a command for managing a buffer that holds a decoded picture as a reference picture, and (ii) a coded picture are recorded;
• and (b) a stream reproduction apparatus which reads the stream from said recording medium and reproduces the stream,
• wherein the stream recorded on said recording medium has a structure in which,
• when a first coded picture is a coded picture corresponding to a picture that is to be skipped at a time of trick-play, the first coded picture being added with a first information obtained by coding the command,
• a second information in which same contents as the command shown by the first information are coded is added to a second coded picture that follows the first coded picture in decoding order and that corresponds to a picture which is not to be skipped at the time of the trick-play, and
• said stream reproduction apparatus, which reads the stream from said recording medium and reproduces the stream, includes
• a first decoding unit operable to decode the second information, when the first coded picture is skipped at a time of trick-play;
• a buffer management unit operable to hold, in a buffer, the decoded picture as a reference picture, depending on contents of the decoded command;
• and
• a second decoding unit operable to decode the second coded picture.