DEVICE AND METHOD FOR EMBEDDING FORGERY DETECTION INFORMATION AND DETECTING FORGERY, AND RECORDING MEDIUM RECORDED WITH PROGRAM CONDUCTING THE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a device and a method for embedding information and detecting forgery, which can discriminate a picture processing and a forgery behavior and can specify which position in a picture forgery is conducted for every area. SOLUTION: A forgery detection information embedding device 1 divides the picture into plural frequency bands and calculates a conversion coefficient. A random number group is generated by using key data and authentication data is generated. Key data is embedded in the conversion coefficient of MRA and authentication data is embedded in the conversion coefficient of MRR. MRA and MRR to which a embedding processing is conducted, are synthesized and the picture where information is embedded is reconstituted. A forgery detection device 2 extracts key data from MRA where the picture is band-divided and authentication data which is originally embedded is generated. Embedded information is extracted from MRR. The picture is divided into the plural blocks composed of plural pixels, which are previously decided. The group of information embedded in the conversion coefficient of MRR expressing a spatial area similar to the respective blocks is compares/collated with the group of corresponding authentication data. Then, the presence or absence of forgery is judged for every area.