Research On Digtal Watermarking Technology Based On Two-Dimensional Codebar Of PDF417

With the development of multimedia technology and network technology, there is growingly accustomed to using the Internet to publish their own multimedia works, which not only brings many convenients to our lives, but also facilitates to criminals. They are free to copy and disseminate any copyrighted digital media publications, which not only seriously affects the normal economic order, but greatly hurts the interests of consumers. Currently, how to protect the copyright of digital products has become a very pressing issue in digital world. Therefore, digital watermarking technology can be divided into contented watermark and non-contented watermark according to whether includes meaningful contents, while the contented watermark, which not only protects carrier of digital products, also includes copyright information associated with carrier of digital products, has practical value. The paper uses PDF417 barcode code image as a watermark image, and has been researching the generation of digital watermarking, scrambling processing, embedded algorithms, and anti-attack tests.The paper introduces the coding standard of PDF417 barcode code and RS error-correcting algorithms, and compiles the encoding and decoding procedures under text mode, byte mode and digital mode of PDF417 2D-barcode according to the standard; On the basis of embedded contents, the PDF417 2D- barcode watermark image generated. In order to improve watermark invisibility, according to the encoding rules of PDF417 code, we realize the cutting and compression to barcode watermark and achieve lossless compression at the ratio of 1:17; To improve the robustness of digital watermarking, we discuss principle of Logsitc chaos Sequence, which has been applied to crambling of the digital image, and realize crambling processing of barcode watermark image.The paper introduces the basic principles, features and the application on the image watermarking technique of wavelet analysis theory and acts as watermarking algorithm theoretical basis. Through gradual improvement of several embedded algorithms in the test, we propose adaptive repetitive embedded watermarking algorithm based on the DCT in wavelet domains. The simulation results show that the algorithm has a better resistance on the Gaussian noise compared to other algorithms.The adaptive repetitive embedded watermarking algorithm based on DCT realizes embedding and extraction from PDF two-dimensional barcode watermarking, and the test verifies that PDF417 barcode image can still achieve error correcting of PDF417 barcode watermarking under the situation of scratches, pollution and attack of noise, and realize successful decoding of barcode.