公开(公告)号：JPH10285562A

公开(公告)日：1998-10-23

申请号：JP8849397

申请日：1997-04-07

Applicant: IBM JAPAN

Inventor： SHIMIZU SHUICHI

IPC: G06F12/14 ,  G06F21/10 ,  G06F21/60 ,  G06T1/00 ,  H04N1/44 ,  H04N7/08 ,  H04N7/081 ,  H04N7/24

Abstract: PROBLEM TO BE SOLVED: To prevent a security hole in advance in the case of applying the data hiding technology for a still image or the like to a moving image or the like by changing embedded processing depending on each time and frame when a frame pattern (mark) consisting of lots of embedded block patterns of some kinds is used to conduct the embedding processing. SOLUTION: Pluralities of contents are made up of pluralities of consecutive frames 15 consisting of sets of single frames 10. In the case of hiding information 30 with respect to contents consisting of pluralities of the frames 15, data are hidden by imbedding pluralities of frame patterns 45 having different block patterns to each of pluralities of the frames 15 to hide the data. A random element R(t) that generates +1, -1 at random depending on time (t) is introduced to the block pattern. Thus, it is prevented that the pattern is estimated by illegal access and it is detected at the same cost as that by a conventional method.