Recording medium and recording method reducing processing load in realization of TS packet level copyright protection, and playback device and playback method for playback of such recording medium

A playback apparatus which reads an AV stream, stream information, and a restoration program from a recording medium and plays back the read AV stream, the restoration program calculating a restoration parameter when executed, wherein

• the AV stream includes a primary video stream and a secondary video stream, the primary video stream and the secondary video stream each including a masked table multiplexed therein and each being divided into a plurality of restoration segments,
• each of the restoration segments is composed of one or more TS packets, the TS packets each being either a transformed TS packet or a non-transformed TS packet,
• the stream information includes:
• a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• and
• a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the secondary video stream,
• each group of TS packets constituting an entry point stores an intra-frame encoded image therein,
• each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is in a predetermined relationship with a presentation time stamp of every N-th entry point of the primary video stream, is a non-transformed TS packet, N being an integer of 2 or more,
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points,
• the playback apparatus comprises:
• a reader circuit that reads the TS packets included in each of the restoration segments in accordance with the first entry map and the second entry map;
• a demultiplexer circuit that demultiplexes the read TS packets into the TS packets composing the primary video stream and the TS packets composing the secondary video stream;
• two video decoders that decode the TS packets composing the primary video stream and the TS packets composing the secondary video stream, respectively;
• a read buffer that buffers TS packets between the reader circuit and the demultiplexer circuit;
• and
• a restoration circuit that executes the restoration program and thereby restores, among TS packets in the read buffer, transformed TS packets, wherein
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments.

A recording apparatus that records, on a recording medium, an AV stream, stream information, and a restoration program calculating a restoration parameter when executed, the AV stream including a primary video stream and a secondary video stream, the recording apparatus comprising:

• a multiplexer circuit that multiplexes a masked table with respect to each of TS packets composing the primary video stream and TS packets composing the secondary video stream, and thereby obtains the primary video stream and the secondary video stream;
• a first entry map generator circuit that generates a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point storing therein an intra-frame encoded image with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• a second entry map generator circuit that generates a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point storing therein an intra-frame encoded image with (b) a presentation time stamp of the group of TS packets of the secondary video stream;
• a specification circuit that divides each of the primary video stream and the secondary video stream into a plurality of restoration segments according to the first entry map and the second entry map, respectively, and specifies as untransformable packets, among the TS packets multiplexed in the restoration segments, each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is closest to the presentation time stamp of every N-th entry point of the primary video stream, N being an integer of 2 or more;
• a transformation circuit that obtains the AV stream by performing a restorable transformation with respect to some of TS packets among the TS packets in the restoration segments other than the untransformable TS packets, the restorable transformation being a replacement of the TS packets with another piece of data and a transformed TS packet obtained through the restorable transformation being restorable by using a restoration parameter;
• a program generator circuit that generates the restoration program;
• and
• a recorder circuit that records, onto a recording medium, the AV stream, the first entry map, the second entry map, and the restoration program, wherein
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments, and
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points.

A playback method which reads an AV stream, stream information, and a restoration program from a recording medium and plays back the read AV stream, the restoration program calculating a restoration parameter when executed, wherein

• the AV stream includes a primary video stream and a secondary video stream, the primary video stream and the secondary video stream each including a masked table multiplexed therein and each being divided into a plurality of restoration segments,
• each of the restoration segments is composed of one or more TS packets, the TS packets each being either a transformed TS packet or a non-transformed TS packet, the stream information includes:
• a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• and
• a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the secondary video stream,
• each group of TS packets constituting an entry point stores an intra-frame encoded image therein,
• each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is in a predetermined relationship with a presentation time stamp of every N-th entry point of the primary video stream, is a non-transformed TS packet, N being an integer of 2 or more,
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points,
• the playback method comprises:
• reading the TS packets included in each of the restoration segments in accordance with the first entry map and the second entry map, and buffering the read TS packets into a read buffer;
• restoring, by executing the restoration program, transformed TS packets among TS packets in the read buffer;
• demultiplexing, from the read buffer, the TS packets composing the primary video stream and the TS packets composing the secondary video stream;
• and
• decoding the TS packets composing the primary video stream and the TS packets composing the secondary video stream, respectively, wherein
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments.

A recording method for a recording medium, comprising:

• creating application data;
• and
• recording the created data onto a recording medium, wherein
• the application data includes an AV stream, stream information, and a restoration program calculating a restoration parameter,
• the AV stream includes a primary video stream and a secondary video stream, the primary video stream and the secondary video stream each including a masked table multiplexed therein and each being divided into a plurality of restoration segments,
• each of the restoration segments is composed of one or more TS packets, the TS packets each being either a transformed TS packet or a non-transformed TS packet,
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments,
• the stream information includes:
• a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• and
• a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the secondary video stream,
• each group of TS packets constituting an entry point stores an intra-frame encoded image therein,
• each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is in a predetermined relationship with a presentation time stamp of every N-th entry point of the primary video stream, is a non-transformed TS packet, N being an integer of 2 or more, and
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points.

An integrated circuit of a playback apparatus which reads an AV stream, stream information, and a restoration program from a recording medium and plays back the read AV stream, the restoration program calculating a restoration parameter when executed, wherein

• the AV stream includes a primary video stream and a secondary video stream, the primary video stream and the secondary video stream each including a masked table multiplexed therein and each being divided into a plurality of restoration segments,
• each of the restoration segments is composed of one or more TS packets, the TS packets each being either a transformed TS packet or a non-transformed TS packet,
• the stream information includes:
• a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• and
• a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point with (b) a presentation time stamp of the group of TS packets of the secondary video stream,
• each group of TS packets constituting an entry point stores an intra-frame encoded image therein,
• each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is in a predetermined relationship with a presentation time stamp of every N-th entry point of the primary video stream, is a non-transformed TS packet, N being an integer of 2 or more,
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points,
• the integrated circuit comprises:
• a reader circuit that reads the TS packets included in each of the restoration segments in accordance with the first entry map and the second entry map;
• a demultiplexer circuit that demultiplexes the read TS packets into the TS packets composing the primary video stream and the TS packets composing the secondary video stream;
• two video decoders that decode the TS packets composing the primary video stream and the TS packets composing the secondary video stream, respectively;
• a read buffer that buffers TS packets between the reader circuit and the demultiplexer circuit;
• and
• a restoration circuit that executes the restoration program and thereby restores, among TS packets in the read buffer, transformed TS packets, wherein
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments.

An integrated circuit of a recording apparatus that records, on a recording medium, an AV stream, stream information, and a restoration program calculating a restoration parameter when executed, the AV stream including a primary video stream and a secondary video stream, the integrated circuit comprising:

• a multiplexer circuit that multiplexes a masked table with respect to each of TS packets composing the primary video stream and TS packets composing the secondary video stream, and thereby obtains the primary video stream and the secondary video stream;
• a first entry map generator circuit that generates a first entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the primary video stream, a group of TS packets which constitute an entry point storing therein an intra-frame encoded image with (b) a presentation time stamp of the group of TS packets of the primary video stream;
• a second entry map generator circuit that generates a second entry map indicating a plurality of associations each associating (a) a start position of, among the TS packets composing the secondary video stream, a group of TS packets which constitute an entry point storing therein an intra-frame encoded image with (b) a presentation time stamp of the group of TS packets of the secondary video stream;
• a specification circuit that divides each of the primary video stream and the secondary video stream into a plurality of restoration segments according to the first entry map and the second entry map, respectively, and specifies as untransformable packets, among the TS packets multiplexed in the restoration segments, each TS packet which constitutes one of the entry points of the secondary video stream and whose presentation time stamp is closest to the presentation time stamp of every N-th entry point of the primary video stream, N being an integer of 2 or more;
• a transformation circuit that obtains the AV stream by performing a restorable transformation with respect to some of TS packets among the TS packets in the restoration segments other than the untransformable TS packets, the restorable transformation being a replacement of the TS packets with another piece of data and a transformed TS packet obtained through the restorable transformation being restorable by using a restoration parameter;
• a program generator circuit that generates the restoration program;
• and
• a recorder circuit that records, onto a recording medium, the AV stream, the first entry map, the second entry map, and the restoration program, wherein
• the restoration program, when executed, restores a transformed TS packet by (i) calculating a restoration parameter for the restoration segment including the transformed TS packet based on a segment identifier provided to the restoration segment, (ii) performing a calculation using the masked table and the restoration parameter, and (iii) overwriting the transformed TS packet with a result of the calculation, the restoration program calculating a different restoration parameter for each of the restoration segments, and
• each of the restoration segments, other than a final one of the restoration segments, has the same fixed number of entry points.