Abstract: A recording/playback device includes an information conversion unit converting video or audio information, received from an external source, to video or audio data for recording on a rewritable optical disk, a recording unit recording the video or audio data on said optical disk, and a playback unit playing back the video or audio data recorded on said optical disk, in which the optical disk has at least two recording layers and, when the video or audio data is recorded in two or more layers of the optical disk and then a part of the video data or audio data recorded in each layer is erased, a part of the video or audio data left unerased is moved so that a number of layers, in which the video or audio data left unerased is recorded, is reduced.

Abstract: An information recording technique which, even when an interruption of recording operation takes place for some reasons, can make the most of the features of a recording medium and can record data on the medium with a good reliability. This can be realized by changing abnormality judging conditions according to the type of the recording medium and changing record resuming conditions after the interruption of the recording operation.

Abstract: When, in the course of recording data to a disk for each basic recording unit, the recording is stopped in the middle of a basic recording unit, data of the basic recording unit of the recording that was stopped remain held in memory. When recording resumes, the recording operation is restarted sequentially from the remaining data held in memory from the position at which recording was stopped. When the remaining data cannot be recorded, dummy data are recorded instead and playback is performed, skipping the dummy data section.

Abstract: Because a series of data is recorded continuously, the recording quality of data recorded in course of recording cannot be evaluated. Accordingly, the laser output cannot be controlled properly and there are a deterioration and dispersion of the recording quality. Further, when the recording lasts for a long time, the temperature in the vicinity of laser rises due to the heat from the inside of a disc drive and the recording quality is deteriorated. To solve this, a series of data to be recorded is split and recording is made intermittently in a split data unit. The recording quality is evaluated by reproducing the data recorded nearby before each split data is recorded using a duration and control is performed by reflecting the evaluation result in the laser output so that the recording quality can be maintained satisfactorily over a series of the whole data to be recorded.

Abstract: A disc device in which recording is possible in a basic recording area in units of a subarea and startable at any position. Even if the recording cannot help stopping due to some external cause during recording on a disc-type recording medium that basically employs real-time sequential recording, the recording is re-openable at the position where the recording stopped when the external cause has disappeared. The disc device includes a reference clock counter that starts to count at the starting point of each basic recording area reference clocks read from the disc, and an address memory that holds an address of the basic recording area under recording. When the recording is stopped due to some external cause, the count of the counter and the address held by the address memory at that time are saved.

Abstract: When, in the course of recording data to a disk for each basic recording unit, the recording is stopped in the middle of a basic recording unit, data of the basic recording unit of the recording that was stopped remain held in memory. When recording resumes, the recording operation is restarted sequentially from the remaining data held in memory from the position at which recording was stopped. When the remaining data cannot be recorded, dummy data are recorded instead and playback is performed, skipping the dummy data section.

Abstract: Because a series of data is recorded continuously, the recording quality of data recorded in course of recording cannot be evaluated. Accordingly, the laser output cannot be controlled properly and there are a deterioration and dispersion of the recording quality. Further, when the recording lasts for a long time, the temperature in the vicinity of laser rises due to the heat from the inside of a disc drive and the recording quality is deteriorated. To solve this, a series of data to be recorded is split and recording is made intermittently in a split data unit. The recording quality is evaluated by reproducing the data recorded nearby before each split data is recorded using a duration and control is performed by reflecting the evaluation result in the laser output so that the recording quality can be maintained satisfactorily over a series of the whole data to be recorded.

Abstract: A disc device in which recording is possible in a basic recording area in units of a subarea and startable at any position. Even if the recording cannot help stopping due to some external cause during recording on a disc-type recording medium that basically employs real-time sequential recording, the recording is re-openable at the position where the recording stopped when the external cause has disappeared. The disc device includes a reference clock counter that starts to count at the starting point of each basic recording area reference clocks read from the disc, and an address memory that holds an address of the basic recording area under recording. When the recording is stopped due to some external cause, the count of the counter and the address held by the address memory at that time are saved.

Abstract: In a method of adjusting a disk apparatus, if adjustment processing has to be performed prior to processing which the user expects to be performed soon, the adjustment processing can be finished in a short time and thus the processing requested by the user can be performed at once enough to meet the user's expectation. A database concerning the adjustment processing is created at the time when the user of the disk apparatus accepts the much time taken to perform the processing requested by the user. Then, when the user makes a request to perform processing, which the user expects to be performed at once, the adjustment processing which has to be performed prior to the performance of the processing requested by the user is performed based on the database to speed up the adjustment processing, thus making it possible to perform the processing requested by the user at once.

Abstract: Processing to confirm management information during starting processing of a disk device is completely executed in a short period of time without scanning a data area to thereby minimize the period of time for the starting processing. The management information confirming processing can be executed after the disk device notifies the condition to the host or the user. Therefore, the response characteristic of the disk device is improved. Authentication information to certify that management information recorded on a disk is valid and invalidating information to invalidate the authentication information are provided. When the invalidating information to invalidate the authentication information is present, it is possible to determine that the management information is invalid or is possibly invalid. When the invalidating information to invalidate the authentication information is absent, it is possible to determine that the management information is valid according to the authentication information.

Abstract: A disc device in which recording is possible in a basic recording area in units of a subarea and startable at any position. Even if the recording cannot help stopping due to some external cause during recording on a disc-type recording medium that basically employs real-time sequential recording, the recording is re-openable at the position where the recording stopped when the external cause has disappeared. The disc device includes a reference clock counter that starts to count at the starting point of each basic recording area reference clocks read from the disc, and an address memory that holds an address of the basic recording area under recording. When the recording is stopped due to some external cause, the count of the counter and the address held by the address memory at that time are saved.

Abstract: An information recording technique which, even when an interruption of recording operation takes, place for some reasons, can make the most of the features of a recording medium and can record data on the medium with a good reliability. This can be realized by changing abnormality judging conditions according to the type of the recording medium and changing record resuming conditions after the interruption of the recording operation.

Abstract: Because a series of data is recorded continuously, the recording quality of data recorded in course of recording cannot be evaluated. Accordingly, the laser output cannot be controlled properly and there are a deterioration and dispersion of the recording quality. Further, when the recording lasts for a long time, the temperature in the vicinity of laser rises due to the heat from the inside of a disc drive and the recording quality is deteriorated.

Abstract: When, in the course of recording data to a disk for each basic recording unit, the recording is stopped in the middle of a basic recording unit, data of the basic recording unit of the recording that was stopped remain held in memory. When recording resumes, the recording operation is restarted sequentially from the remaining data held in memory from the position at which recording was stopped. When the remaining data cannot be recorded, dummy data are recorded instead and playback is performed, skipping the dummy data section.

Abstract: An information recording and control method and apparatus for a recording medium disc having information previously recorded thereon. New information is overwritten at least a portion of the previously recorded information in a recording area of the recording medium disc. Information on the new information is cataloged as control information on the recording medium disc. Residual information which is part of the previously recorded information which is not overwritten by the new information is treated as new information and information on the residual information which is treated as new information is cataloged as control information on the recording medium disc.