Abstract: There are provided a mounting unit configured to selectively mount first and second optical disks in which characteristics of recording films are different from one another, and a discriminating unit configured to discriminate which of the first and second optical disks is mounted on the mounting unit based on a level of a reproduction signal which is obtained by reproducing innermost peripheral portion of the first or second optical disk mounted on the mounting unit.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: Video data divided into a plurality of cells, attribute information for specifying the playback order of the plurality of cells, and a flag for specifying whether the playback can be effected or not for each of the plurality of cells are recorded on an optical disk. In a playback apparatus, the cell which is specified to be inhibited from being played back by the flag is not played back when a plurality of cells are played back based on the playback order specified by the attribute information.

Abstract: When an error-correcting code is created for the data stored in a memory and added to the data, even if an error occurs in the data on the memory, the adverse effect of the error will be eliminated. In the present invention, when the data is stored in the memory, an error-correcting code PI is created beforehand using another memory, such as an S-RAM. The error-correcting code PI, together with the data, is written into the memory. After 16 sectors of data and PI have been stored, an error-correcting code PO is created for the data and PI and added to them. When the data is read from the memory, a PI correcting process is carried out each time a PI series is read out. This makes it possible to restore the original data, even if the data is destroyed (or an error occurs) on the memory.

Abstract: Video data divided into a plurality of cells, attribute information for specifying the playback order of the plurality of cells, and a flag for specifying whether the playback can be effected or not for each of the plurality of cells are recorded on an optical disk. In a playback apparatus, the cell which is specified to be inhibited from being played back by the flag is not played back when a plurality of cells are played back based on the playback order specified by the attribute information.

Abstract: Video data divided into a plurality of cells, attribute information for specifying the playback order of the plurality of cells, and a flag for specifying whether the playback can be effected or not for each of the plurality of cells are recorded on an optical disk. In a playback apparatus, the cell which is specified to be inhibited from being played back by the flag is not played back when a plurality of cells are played back based on the playback order specified by the attribute information.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: To convert a 12-bit data word into an 18-bit code word, the 12-bit data word is divided into the 8 high-order bits and the 4 low-order bits. The 8 high-order bits are converted into 12 bits and the 4 low-order bits are converted into 6 bits, thereby creating an 18-bit code. This enables conversion using small-scale conversion tables.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

Abstract: An information recording medium includes a first area (DA2) for storing picture data for forming a plurality of pictures, a second area (DA21) which is included in the first area and stores control data of the picture data, and a third area (INFO1) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.