Reproduction device, optical disc, recording medium, program, reproduction method

摘要

A playback apparatus not only plays back an AV stream recorded on a BD-ROM but also downloads an update kit from a WWW server (500) and writes it on a local HD (12). The AV stream stored in the local HD (12) includes an audio stream for an additional language. A control unit (16) reads the AV stream recorded on the BD-ROM and the AV stream recorded in the local HD (12) in units of access units. An audio decoder (6) obtains a necessary audio frame from the access units read from the BD-ROM and the local HD (12) and plays it back. A video decoder (4) obtains video data from the access unit read from the BD-ROM and plays it back.