Playback apparatus for performing application-synchronized playback

A playback method employed by a playback apparatus for playing a digital stream in conjunction with an application executing in the playback apparatus, comprising:

• generating, with a package manager provided in the playback apparatus, package information by merging a first file recorded on a first recording medium and a second file recorded on a second recording medium, in accordance with merge management information recorded on the second recording medium, the merge management information indicating the second file on the second recording medium for merging with the first file on the first recording medium;
• detecting, with a selector provided in the playback apparatus, a plurality of titles from the package information and selecting one of the detected titles as a current title;
• executing, with an application executor provided in the playback apparatus, an application associated with the current title, the application being operable to request the package manager to generate new package information using new merge management information, the new merge management information referencing a third file on the second recording medium for merging with the first file on the first recording medium;
• and
• controlling, with a playback controller provided in the playback apparatus, playback of the digital stream associated with the current title, wherein
• the third file is set, by the package manager, to read-only when the application requests generation of the new package information,
• the new package information is generated, by the package manager, when the digital stream playback stops due to a change of the current title,
• the second recording medium includes a plurality of disc dependent areas, and
• one of the plurality of disc dependent areas corresponding to the first recording medium is identified, by the package manager, and the merge management information in the one of the plurality of disc dependent areas is replaced, by the package manger, with the new merge management information specified by the application.

A program recording medium embodying a playback program that causes a playback apparatus to play a digital stream in conjunction with an application executing in the playback apparatus, the playback program comprising program code segments that cause the playback apparatus to execute:

• generating package information by merging a first file recorded on a first recording medium and a second file recorded on a second recording medium, in accordance with merge management information recorded on the second recording medium, the merge management information indicating the second file on the second recording medium for merging with the first file on the first recording medium;
• detecting a plurality of titles from the package information and selecting one of the detected titles as a current title;
• executing an application associated with the current title, the application being operable to request a package manager to generate new package information using new merge management information, the new merge management information referencing a third file on the second recording medium for merging with the first file on the first recording medium;
• and
• controlling playback of the digital stream associated with the current title, wherein
• the third file is set to read-only when the application requests generation of the new package information,
• the new package information is generated when the digital stream playback stops due to a change of the current title,
• the second recording medium includes a plurality of disc dependent areas, and
• one of the plurality of disc dependent areas corresponding to the first recording medium is identified, by the package manager, and the merge management information in the one of the plurality of disc dependent areas is replaced, by the package manger, with the new merge management information specified by the application.