Abstract: A data compensating method and apparatus for compensating a block from which data cannot be read due to the presence of a scratch or dust when reproducing an optical disk are provided. The data compensating method includes the steps of: (a) setting a first block region for storing a block of data currently being reproduced and a second block region for storing the previous block of data, and reproducing the disk according to a read command; (b) determining the type of data block from a header in a sought block when the number of seek operations is greater than a predetermined value in reproducing the disk in step (a); (c) substituting an address of a block of data in the second block region, corresponding to a data block determined in step (b), for an address requested by a host; and (d) transmitting to the host the block of data in the second block region substituted in step (c).

Abstract: For recording data on and reproducing data from an optical disk of a single spiral land/groove configuration, a header detector detects header regions on the optical disk, a PID error detector judges whether the address information read from the header regions is erroneous, using error detection codes, and detects the number of errors per sector. An error count comparator compares the number of errors per sector with a predetermined value, and a state judging circuit identifies the state of the optical disk device by causing transition to a higher or lower state according to the output of the error count comparator. The recording and reproduction are controlled according to the state thus identified.

Abstract: A control system realizes a playback function by playing back stream data read out from a medium by using a decoder. When special playback functions corresponding to pause, fast forward, and rewind are to be performed, the control system moves a read start pointer to the head of a data block constructing a data format, and sets as a restart position of a playback operation.

Abstract: A method and an apparatus are provided for reproducing data recorded in a format different from CD, such as recorded in ISO9660 format. Specifically, TOC data is generated from the information of a path table storing directory information of different stages (TOC data generating section), and information recorded in a format different from CD is reproduced in accordance with the TOC data (information reproducing section).

Abstract: Data in CD signal format is recorded to a first session. Compressed digital data in CD-ROM format in double density is recorded to a second session. Addresses of the first session are represented in notation of minute, second, and frame. Addresses of the second session are represented in binary notation. At step S1, it is determined whether or not the first session is accessed. When the first session is accessed, the generation of normal addresses is started (at step S2). When the determined result represents that the first session is not accessed, the gap length is calculated at step S3. At step S4, the start address of the second session is generated with (end address+gap length). At step S5, it is determined whether or not the second session has ended. Unless the second session ends, the generation of the second addresses is continued. When the second session ends, the generation of addresses is stopped.

Abstract: Data in the same signal format as conventional CD is recorded to a first part PA1. Compressed digital data in CD-ROM format in double density is recorded to a second part PA2. Addresses of a first session including the first part are represented in the notation of minute, second, and frame. Addresses of a second session including the second part are represented in binary notation. When the record position moved from first session to the second session, the end address of the first session is converted into an address of the second session (at step S3). At step S4, designating the start address as address B, second addresses (for example, addresses represented in binary notation) are generated. When there is a non-record portion between the two sessions, an address value corresponding to the non-record portion is added to the start address. The resultant address is used as the new start address.

Abstract: Management information is read from an information storage medium having the management information recorded thereon, the management information including track number information imparted to at least one track and group management information for managing as selective recording information one or a plurality of tracks as one group. Judgment is then made upon whether the group management information is included in that management information, A display mode is changed depending on a case where the group management information is recorded and a case where it is not recorded, and it is then displayed in a displaying device.

Abstract: A method and apparatus for information signals in which, in recording and/or reproducing information signals responsive to a request from a host device, a first address defined with the time domain information is converted into a second address defined with consecutive hexadecimal numbers and vice versa by way of reciprocal address conversion. Specifically, an uppermost order value in the time domain information in the first address and a second address value are converted reciprocally using a conversion table.

Abstract: An optical disk recording apparatus for recording a main information signal reproduced from a first optical disk on a second optical disk includes a first part which set an address of a start point of each of tracks of the first optical disk and an address of a position ahead of the start point by a predetermined period of time, a second part which searches a part between the start point and the position ahead of the start point of each of the tracks for an address within a range where each of index values included in subcodes reproduced with the main information signal is zero, and a third part which, with respect to each of the tracks, sets the index values within the range to zero and index values other than the index values within the range to a predetermined value other than zero, and records the index values on the second optical disk together with the main information signal.