Abstract: According to the data amount and the nature of a video stream and an audio stream included in a program stream which is to be decoded, an audio and video processing apparatus performs processing while allocating higher priority to one or the other of the video and audio streams. Without any increase in circuit complexity or clock speed, this apparatus can reproduce streams in at least two formats, in which the ratios of the amounts of encoded signal data and of the amounts of calculation required for decoding for the video and the audio are very different.

Abstract: A video signal reproduction apparatus is provided for reproducing a multiplexed encoded stream including audio data, video data, sub-picture data, and additional information digitally encoded and multiplexed on a packet-by-packet basis. The multiplexed encoded stream includes a plurality of packs, each of the plurality of packs including at least one packet, the at least one packet including a packet header and packet encoded data. The packet encoded data includes at least one of packet audio encoded data, packet video encoded data, packet sub-picture encoded data, and packet navigation encoded data. The packet audio encoded data forms sub-picture encoded data, the sub-picture encoded data including a first reproduction unit and a second reproduction unit. The first reproduction unit includes a first unit header, first encoded bit map data, and first display control information, and the second reproduction unit includes a second unit header, second encoded bit map data, and second display control information.

Abstract: According to the data amount and the nature of a video stream and an audio stream included in a program stream which is to be decoded, an audio and video processing apparatus performs processing while allocating higher priority to one or the other of the video and audio streams. Without any increase in circuit complexity or clock speed, this apparatus can reproduce streams in at least two formats, in which the ratios of the amounts of encoded signal data and of the amounts of calculation required for decoding for the video and the audio are very different.