ELECTRONIC EQUIPMENT, DATA PROCESSING METHOD, DIGITAL WATERMARK SYSTEM, DATA PROCESSING SYSTEM, AND STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a data processing system capable of simultaneously satisfying the extraction of optional digital watermark information by a general user and the protection of digital data copyright. SOLUTION: A 1st padding means 101 pads 1st information D1 in digital data G by using a disclosed key kp. A 2nd padding means 104 pads 2nd information D3 in order to restore the 1st information D1. Consequently a receiving side (for digital data G') can optionally extract the 1st information D1 from the digital data G' by using the disclosed key kp, and even when the 1st information D1 in the digital data G' is destructed, the information D1 can be restored by the 2nd information D3.