| 摘要 |
PURPOSE:To use effectively a storage capacity, by providing the recording mode, where the redundancy is raised to improve the information reliability, and the recording mode, where the redundancy is lowered to increase the storage capacity, for a storage medium. CONSTITUTION:An optical disc controller 2 decodes commands from a computer 1 and allows an optical disc device 3 to execute a prescribed operation under the control of a microprogram muPG. A recording track 4 on an optical disc consists of plural fixed-length sectors 5. The sector 5 consists of an ID field 6 and a data field 7, and the field 6 indicates the physical position of the sector 4 on the optical disc, and a track number and a sector number are written in the sector 4. A recording mode (a) consisting of a data part 8 and an error correction code ECC part 9 and a recording mode (b) consisting of only a data part 8' are provided for the field 7. The mode (a) which raise the redundancy to improve the reliability is used in an index part indicating the recording position of picture information, and the mode (b) which increases the storage capacity is used for picture information, and they are controlled by the muPG. |
