| 摘要 |
PROBLEM TO BE SOLVED: To provide an access control system that has a data corruption function with rigid illegitimate decoding immunity and can optionally control the degree of data corruption so as to attain the compatibility between copyright protection and incentive to raise user's viewing desire. SOLUTION: In an information processing system wherein moving picture contents are generated and reproduced, a contents data generating apparatus embeds an encryption key to the moving picture contents as an electronic watermark, encrypts part of elements of the moving picture contents by using the encryption key, transfers the encrypted contents data to a contents data reproducing apparatus, the contents data reproducing apparatus detects the electronic watermark from the moving picture contents, acquires the encryption key, and uses the encryption key to decode the encrypted contents data the part of elements of which are encrypted to acquire contents data. COPYRIGHT: (C)2004,JPO |
