Certificates Anti-counterfeiting Based On Digital Watermarking And ARM

With the rapid development of information technology and network technology,multimedia data transmission and replication becomes more easily.How to protect the data puts forward higher requirements.In our real life,the most important documents such as commercial documents,confidential documents,certificates and notes are kept in the form of printed papers.Previous digital watermarking algorithms are mainly designed for the copyright protection of digital media,less to printed images.Print-and-scan resilient is a key problem to the digital watermarking technology of printed image.Print-and-scan process is a strong attack to images.Most of watermarking algorithms cannot be tested or extracted after analog-to-digital conversion and digital-to-analog conversion,let alone print-and-scan attack.Combining with the current application background and research status of digital watermarking,the print-and-scan resilient document image digital watermark technology is studied,and some valuable research results are obtained.At first,this paper introduces the current application background and research status of certificate anti-counterfeiting digital watermark,and states digital watermarking technology characteristics,its classification and typical algorithms.And then the print-and-scan process is studied which affects the image quality.The DCT coefficients before and after print-and-scan are studied,found there is an approximate invariant.In this case,it proposes a print-and-scan resilient digital watermarking algorithm based on the plus or minus number of the DCT coefficients.The algorithm has good robustness and can resist to print-and-scan process effectively.Using the Arnold scrambling algorithm to scramble watermark image has good scrambling effect and is safety.Then the design and implementation of certificate anti-counterfeiting digital watermarking system are based on Visual C+ + 6.0 and Open CV and the system is tested.Then,the certificate anti-counterfeiting digital watermarking system based on Visual C + + 6.0 and Open CV is transplanted into the development board S3C6410 and to be tested.Finally,the paper is summarized and prospected according to the experimental results of the watermarking system,and gives the next step work ant its arrangements.