VERIFICATION DATA EMBEDDING METHOD, PROGRAM AND APPARATUS, IMAGE TAMPERING DETECTING METHOD, PROGRAM, APPARATUS, AND IMAGE TAMPERING DETECTION SYSTEM

摘要

PROBLEM TO BE SOLVED: To embed verification data in such a way that it is hard to locate the verification data embedding position, and that tampering by exchange of verification data is prevented. SOLUTION: A dividing part 13b divides a block obtaining a division result value into two parts of a "verification data calculation part" and a "verification data embedding part" based on a designation of a designating part 13d. A verification data preparing part 16 obtains a hash value by inputting a division result value D(J, m)/Q(J, m) corresponding to DCT coefficient of verification data calculation part B(J) and an initial vector value VI of the hash function inputted from an initial vector input part 17 into a hash function. A data bit string of the obtained hash value is outputted to a verification data embedding part 13c as verification data. The verification data embedding part 13c embeds the verification data every bit at an embedding position serving as a predetermined coefficient position of a verification data embedding part B(K). COPYRIGHT: (C)2008,JPO&INPIT