A New Decoding Method for Digital Watermark Based on Error Correcting Codes and Cryptography

摘要

It is conceivable to embed additional information with a view to judge whether certificates existing as paper media or digital image data have been altered. The authors have already proposed and discussed a method for configuration of image information enabling reconstruction of the original image information from contaminated image information on paper by means of coding theory. Based on this proposal, a new method is being proposed for effective detection of alteration of digital image data by applying coding theory and the cryptographic theory at the same time. In the present paper, this method is critically discussed and a new method is proposed.