| 摘要 |
PROBLEM TO BE SOLVED: To provide the falsification detection method where a falsified position of an electronic image is located. SOLUTION: A distributor side generates transmission digests DA, DB, DD, DC based on division images A-D that denote sequenced electronic image divisions according to each area, the digests are imbedded to the division images A-D as shown in figure (h), and the division images A-D are built up in a form of the original image to reconfigure the entire image. Then an entire authentication digest generated from this entire image is distributed together with the entire image. A receiver side generates an entire image collation digest from the distributed entire image and compares it with the distributed entire image authentication digest to discriminate presence of an entirely falsified part. In the case that an entirely falsified part is in existence, reception digests D'A, D'B, D'D, D'C are generated and sequentially moved down from division images A-D read from the entire image according to the sequencing as above, and they are sequentially compared with the transmission digests sequentially to detect the presence of falsification for each division area. |
