A write-once type information recording medium according to one aspect of the present disclosure includes at least one recording layer. In the information recording medium, the at least one recording layer has a spiral shape in which a land track and a groove track are alternately arranged as a recording track, the recording track is divided into blocks each of which being minimum unit in which recording is performed, and the information recording medium includes a management information area where management information is recorded and a user data area where user data is recorded. Each of the management information areas of both the land track and the groove track on each recording layer of the at least one recording layer is disposed at a same distance from the center of the information recording medium.

A data recording device includes a recording medium, a control circuit configured to execute a read operation to read data from the recording medium or a write operation to write data on the recording medium, in response to a read or write request from an external device, and in accordance with one of a plurality of recording methods, a cache, a storage circuit configured to store a cache priority table in which a priority for storing read data or write data in the cache is set for each of the recording methods, and a cache control circuit configured to store the read data or the write data in the cache according to a priority set in the cache priority table for the read data and the recording method for the read data or for the write data and the recording method for the write data.

An object of the present invention is to realize an imaging device and recording control system in which the usability thereof can be improved dramatically. In an imaging device configured to output imaging data that is obtained as a result of imaging of an object, and a recording control system, the imaging device comprises a control means for recognizing a controlled state of an external recording device when a communication is enabled with the recording device through a communication means conforming to a predetermined transmission method and an input means for allowing the recording device to execute an application needed for a recording operation obtained by controlling the recording device, and the recording device records the imaging data obtained through the communication means when the application is executed by means of the input means.

In an information recording device, when receiving an erase command by a receiver, a controller erases data of an erased area by overwriting data in an information area, to corrupt the data in the information area, using an erasing pattern. The erased area is specified by an erase start position and a size of the data to be erased on the optical disc. The data in the information area is arranged as partial data in a series of data arranged in a direction of internal parity of error correction so that correction is disabled in both of a correction processing by the internal parity of the error correction and a correction processing by external parity of the error correction when the data in the information area is overwritten using the erasing pattern.

In an information recording device, when receiving an erase command by a receiver, a controller erases data of an erased area by overwriting data in an information area, to corrupt the data in the information area, using an erasing pattern. The erased area is specified by an erase start position and a size of the data to be erased on the optical disc. The data in the information area is arranged as partial data in a series of data arranged in a direction of internal parity of error correction so that correction is disabled in both of a correction processing by the internal parity of the error correction and a correction processing by external parity of the error correction when the data in the information area is overwritten using the erasing pattern.

On each of a plurality of recording layers of a write-once optical disc, two tracks constituted of adjacent land and groove are formed in a spiral shape. A writing method of data includes: a step of receiving data and a writing instruction of the data; and a step of recording management information, wherein the management information includes: virtual sequential recording range information that manages a last recorded address of the data as a virtual physical sector number; defect list that indicates a replacement correspondence relationship between the virtual physical sector number and an actually recorded physical sector number; and real next writable address information that indicates a real next writable address that is actually recordable subsequently to the physical sector number.

A system may include a key management server configured to store encryption keys. The system may also include a storage device that includes a processor, a memory coupled to the processor, and an optical medium coupled to the processor. The processor may be configured to encrypt and write data to the optical medium based upon the encryption keys, the data having metadata associated therewith, store the metadata in the memory, and read selected encrypted data from the optical medium. The processor may also be configured to retrieve the metadata associated with the selected encrypted data, retrieve a respective encryption key based upon the retrieved metadata, and decrypt the selected encrypted data based upon the respective encryption key. The processor may further be configured to delete selected metadata from the memory in response to a delete instruction so that the respective data is unreadable.

A method of storing a substantially real time stream of information signals arranged in separate, consecutive data packets of digital format on a disc like record carrier. A new stream pack (S_PCK) is defined comprising a pack header and a multiple of source packets containing said data packets with corresponding added time stamps related to a time of arrival of said data packets. The pack header comprises data packet retrieval information, such as the number of new source packets in the stream pack and the effect of the start location of the first source packet in the stream pack. Preferably private stream 2 of the MPEG-format is employed for this new stream.

On each of a plurality of recording layers of a write-once optical disc, two tracks constituted of adjacent land and groove are formed in a spiral shape. A writing method of data includes: a step of receiving data and a writing instruction of the data; and a step of recording management information, wherein the management information includes: virtual sequential recording range information that manages a last recorded address of the data as a virtual physical sector number; defect list that indicates a replacement correspondence relationship between the virtual physical sector number and an actually recorded physical sector number; and real next writable address information that indicates a real next writable address that is actually recordable subsequently to the physical sector number.

An object of the present invention is to realize an imaging device and recording control system in which the usability thereof can be improved dramatically. In an imaging device configured to output imaging data that is obtained as a result of imaging of an object, and a recording control system, the imaging device comprises a control means for recognizing a controlled state of an external recording device when a communication is enabled with the recording device through a communication means conforming to a predetermined transmission method and an input means for allowing the recording device to execute an application needed for a recording operation obtained by controlling the recording device, and the recording device records the imaging data obtained through the communication means when the application is executed by means of the input means.