| 摘要 |
PROBLEM TO BE SOLVED: To provide an encoding method and a decoding method for contents, capable of preventing encoded contents obtained by encoding contents data from being decoded, when the encoded contents are decoded. SOLUTION: Contents data is reversibly compressed and encoded, to obtain reversibly compressed contents, and an encoded environment parameter encoded is read and recorded on a recording medium together with a decoded program. Once the decoded program is started in a computer (S11), the encoded environment parameter is read from the recording medium (S12), and a decoded environment parameter is read from the computer (S13). When both the environment parameters are compared (S14), and possibility of illegal duplication is low, the reversible compressed contents are decoded (S15). When the possibility of the illegal duplication is high and an input CPU-ID does match (S17), it is decided as being illegal duplication, and the decoding of the reversibly compressed contents will not be allowed (S19). COPYRIGHT: (C)2004,JPO |
