| 摘要 |
PROBLEM TO BE SOLVED: To attain the security of disk contents. SOLUTION: A data reproducing device comprises a subcode decoder 74 to which a reproduced signal is supplied from a recording medium 10, a plurality of storing means 76 and 78 for generating a plurality of polynominals used at decode processing, a memory means 84 stored with the insertion address of secret data, and a control part 82 for controlling decode processing of subcode data. A polynominal G<SB>1</SB>(x) used in decoding data except the secret data is different from a polynominal G<SB>2</SB>(x) used in decoding the secret data. Only when the polynominal G<SB>2</SB>(x) is used, the secret data can be reproduced, so that information on the secret data can be acquired. For example, in the case of key information for contents encryption, contents can be decoded by the key information. Thus, the security of the contents recorded on the recording medium can be ensured. In the case of the polynominal G<SB>1</SB>(x), since an error appears, the secret data can not be obtained. COPYRIGHT: (C)2004,JPO |
