Abstract: A two-dimensional encoder stores data on a holographic memory. The encoder encodes data of k bits (where k is an integer and k?3) into n pixels arranged two-dimensionally (where n is an integer and n?6). The encoder includes a first processing section 31 for classifying the n pixels into first and second groups of subblocks 11 and 12 using k1 bits out of the data of k bits (where k1 is an integer and k1?1). Each of the subblocks 11 in the first group consists of m pixels (where m is an integer and m?2), and the number of the subblocks 11 forming the first group is s1 (where s1 is an integer and s1?2). Each of the subblocks 12 in the second group also consists of m pixels, and the number of the subblocks 12 forming the second group is s2 (where s2 is an integer and s2?1).

Abstract: A recording medium for storing a data stream is comprised of first error correcting codes obtained by encoding first information, second error correcting codes obtained by encoding second information, and synchronization signals. In the data stream, the second error correcting codes and the synchronization signals alternatively interleave the first error correcting codes. The second error correcting codes have the same number of corrections as the first error correcting codes. A code length of the second error correcting codes is shorter than a code length of the first error correcting codes.

Abstract: An ECC block is constituted by RS(248, 216, 33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: A recording medium for storing a data stream is comprised of first error correcting codes obtained by encoding first information, second error correcting codes obtained by encoding second information, and synchronization signals. In the data stream, the second error correcting codes and the synchronization signals alternatively interleave the first error correcting codes. The second error correcting codes have the same number of corrections as the first error correcting codes. A code length of the second error correcting codes is shorter than a code length of the first error correcting codes.

Abstract: An optical storage medium can be provided by which illegal usage of the optical storage medium involving an infringement on the copyright can be prevented effectively without impairment of the functions for reproducing physical format information and optical storage medium manufacturing information. The optical storage medium includes a main information region in which encrypted data information is recorded as a pit row that is capable of being read out by means of light and a control data region. In the control data region, key information for decoding the encryption of the data information, the physical format information and the optical storage medium manufacturing information are recorded by wobbling a groove.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: An optical storage medium can be provided by which illegal usage of the optical storage medium involving an infringement on the copyright can be prevented effectively without impairment of the functions for reproducing physical format information and optical storage medium manufacturing information. The optical storage medium includes a main information region in which encrypted data information is recorded as a pit row that is capable of being read out by means of light and a control data region. In the control data region, key information for decoding the encryption of the data information, the physical format information and the optical storage medium manufacturing information are recorded by wobbling a groove.

Abstract: An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are caculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: An optical storage medium can be provided by which illegal usage of the optical storage medium involving an infringement on the copyright can be prevented effectively without impairment of the functions for reproducing physical format information and optical storage medium manufacturing information. The optical storage medium includes a main information region in which encrypted data information is recorded as a pit row that is capable of being read out by means of light and a control data region. In the control data region, key information for decoding the encryption of the data information, the physical format information and the optical storage medium manufacturing information are recorded by wobbling a groove.

Abstract: An optical storage medium can be provided by which illegal usage of the optical storage medium involving an infringement on the copyright can be prevented effectively without impairment of the functions for reproducing physical format information and optical storage medium manufacturing information. The optical storage medium includes a main information region in which encrypted data information is recorded as a pit row that is capable of being read out by means of light and a control data region. In the control data region, key information for decoding the encryption of the data information, the physical format information and the optical storage medium manufacturing information are recorded by wobbling a groove.

Abstract: Sub-information necessary to reproduce main information is recorded without deteriorating the reading accuracy of the main information, so that the illegal duplication of an optical disc is prevented. An optical disc 1 is produced by forming a reflective film 1L on concave and convex marks MK after the concave and convex marks MK synchronized with the integral multiple of a channel bit length are formed in accordance with modulated main information. Thereafter, continuous or intermittent laser light synchronized with the integral multiple of the channel bit length is irradiated at intervals longer than the longest one of the concave and convex marks MK in accordance with a spiral track formed in a circumferential direction of the concave and convex marks MK, whereby an optical characteristic of the reflective film 1L is changed to form a recordable mark SMK and sub-information necessary to reproduce the main information is recorded in a superimposition manner.

Abstract: A recording medium comprising a recording area, the recording area includes a first area and a second area, the first area includes a frame area, the frame area includes an area in which a second synchronization code sequence and at least a portion of data are to be recorded, and the second area includes an area in which a third synchronization code sequence and a fourth synchronization code sequence are to be recorded.

Abstract: A recording medium comprising a recording area, the recording area includes a first area and a second area, the first area includes a frame area, the frame area includes an area in which a second synchronization code sequence and at least a portion of data are to be recorded, and the second area includes an area in which a third synchronization code sequence and a fourth synchronization code sequence are to be recorded.

Abstract: A recording medium for storing a data stream is comprised of first error correcting codes obtained by encoding first information, second error correcting codes obtained by encoding second information, and synchronization signals. In the data stream, the second error correcting codes and the synchronization signals alternatively interleave the first error correcting codes. The second error correcting codes have the same number of corrections as the first error correcting codes. A code length of the second error correcting codes is shorter than a code length of the first error correcting codes.

Abstract: To record specific information to a disk-shaped record medium and reproduce the recorded specific information without any influence on the error correction capability. Copy protection information (CPID) having an error correction code appended thereto, shuffled and otherwise treated is sent as a CPID bit block to an EDC rewrite circuit (14). The EDC rewrite circuit (14) rewrites an error detection code appended to user data in each sector in accordance with bit information in the CPID bit block. Thereafter, the data in each sector is scrambled, and an ECC block including a plurality of sectors is modulated with an error correction code and sync signal appended thereto. The modulated signal is recorded in a reserve area of a lead-in area of the disk-shaped record medium. During reproduction, CPID is restored based on the result of error detection of each sector.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: A recording medium comprising a recording area, the recording area includes a first area and a second area, the first area includes a frame area, the frame area includes an area in which a second synchronization code sequence and at least a portion of data are to be recorded, and the second area includes an area in which a third synchronization code sequence and a fourth synchronization code sequence are to be recorded.

Abstract: A recording medium comprising a recording area, the recording area includes a first area and a second area, the first area includes a frame area, the frame area includes an area in which a second synchronization code sequence and at least a portion of data are to be recorded, and the second area includes an area in which a third synchronization code sequence and a fourth synchronization code sequence are to be recorded.

Abstract: A wobble demodulator for reproducing digital information from an optical recording medium in which a track is formed in accordance with a wobble signal that is MSK-modulated so as to contain the digital information by a carrier signal with a predetermined frequency and a sine wave signal with a frequency different from that of the carrier signal, includes: a wobble signal detector for detecting a wobble signal of the track from the optical recording medium; a wobble PLL for detecting the carrier signal based on the wobble signal detected by the wobble signal detector; a multiplier for multiplying the carrier signal detected by the wobble PLL by the wobble signal detected by the wobble signal detector and outputting a multiplied output; a MSK detector for detecting a MSK modulation mark having a phase or a frequency different from that of the carrier signal, based on an integrated value obtained by integrating the multiplied output from the multiplier on a predetermined section basis; and a MSK synchronization

Abstract: A data converter (1) capable of reducing a size of the total implementation in a device is a processing apparatus that performs secret converting processing predetermined to input data with 64 bits, the data converter including a finite field polynomial cubing unit (10), data integrating units (11a) to (11d), (12) and (13), a first converter (14), a second converter (15), a data splitting unit (16), and a data integrating unit (17). The finite field polynomial cubing unit (10) performs cubing, on the 32 bits data, in the polynomial residue class ring with a value in the finite field GF (28) as a coefficient and respectively outputs data with 32 bits.