A print-scan resistable digital seal system

Digital seal can be used to assure the authenticity, integrity and undeniability of electronic documents. In this paper, we implement a new digital seal system called as ASS (AssureSeal System) based on digital watermarking and digital signature technologies. ASS can protect not only the electronic documents, but also their paper copies through digital signature as well as robust and reliable digital watermarking technology. First we introduce the framework and the function modules of ASS, then propose a new technology that adds seal image into electronic documents, which combines the patented binary digital watermarking algorithm with normal digital signature technology, integrated PKI digital certificate. At last, we introduce the specifications and applications of ASS.