Abstract: A recording apparatus such as an optical disk and a file management method are disclosed by which wastefulness caused by free slots in an index file can be reduced. To each slot of a property entry of the index file, valid/invalid information representative of whether the slot is valid or invalid is set. Further, to the header of the property entry, a last valid slot number indicative of a last one of those slots which are set to valid with the valid/invalid information is set.

Abstract: A recording apparatus such as an optical disk and a file management method are disclosed by which, where an index file is formed from groups of data wherein extract information is collected for different types and one of the groups of data is used to collectively manage the other groups of data, a process relating to deletion or addition of extract information can be executed simply, easily, and with certainty. In each of slots of a property entry, information representing whether the slot is valid or invalid and information representative of a relationship to different slots to which extract information relating to the same file is allocated are recorded, and a combination of the slots in which the extract information of the one file is allocated is managed with the property entry.

Abstract: A file managing apparatus is disclosed which is capable of restoring deleted files with ease. When a user gives an instruction to delete a file 6, a parent entry number for the file 6 is changed from “1” to “2” in a property list having the entry number 6 associated with the file 6. Because the parent entry number that is set for the value “2” points to the entry of a recycle bin, the file 6 is placed in a virtually deleted state. Any virtually deleted file is later restored easily through simple processing.

Abstract: The present invention is applied, for example, to a video disk apparatus such that a new folder is produced on a recording medium in response to an operation of a folder switch which accepts an instruction to produce a folder and a result of image pickup is recorded under the produced folder.

Abstract: Before each content file is recorded first to a recording medium, a flag indicating a recording state of a content file is generated corresponding to a physical area where an index file can be continuously recorded. An index file is generated which associates attribute information with the generated flag added thereto with real data of each content file, and the generated index file is recorded to the recording medium. Since fragmentation of the physical area where the index file is recorded is restrained to a minimum level, a high-speed reading operation is realized.

Abstract: A recording apparatus such as an optical disk and a file management method are disclosed by which, where an index file is formed from groups of data wherein extract information is collected for different types and one of the groups of data is used to collectively manage the other groups of data, a process relating to deletion or addition of extract information can be executed simply, easily, and with certainty. In each of slots of a property entry, information representing whether the slot is valid or invalid and information representative of a relationship to different slots to which extract information relating to the same file is allocated are recorded, and a combination of the slots in which the extract information of the one file is allocated is managed with the property entry.

Abstract: A recording apparatus such as an optical disk and a file management method are disclosed by which wastefulness caused by free slots in an index file can be reduced. To each slot of a property entry of the index file, valid/invalid information representative of whether the slot is valid or invalid is set. Further, to the header of the property entry, a last valid slot number indicative of a last one of those slots which are set to valid with the valid/invalid information is set.

Abstract: A recording apparatus and a file management method are disclosed which can be applied typically to an optical disk apparatus and make it possible to grasp a hierarchical structure readily and register or delete extract information simply and easily. Reference information pointing to slots of a higher hierarchy, a lower hierarchy and the same hierarchy is set, and a flag is set to delete or register extract information without varying the reference information.

Abstract: Parallel light rays are applied to a cylinder and true exit positions of the rays from the cylinder are measured, phantom exit positions for the incident rays are calculated by using a mathematical function representing a phantom refractive index profile, and the mathematical function is modified so as to minimize the sum of the squared differences between the true and phantom exit positions.