Research Of Digital Image Watermarking Algorithm Based On Wavelet Transform

With the rapid development of computer networks and widely application of mul-timedia technology, the communication of digital media, such as audio, images, video, etc, have reached a depth and breadth of unprecedented. Following come, the digital information of online dissemination is facing many challenges-various modifications, copying and theft, etc, so digital information security and copyright protection have paid more and more attention by people. In such a background, digital watermarking technology as an effective means of protection of multimedia information security is born, which provide a new idea for the protection of multimedia information and the legitimate use of copyright information.Wavelet analysis, as a powerful time-frequency analysis technology, function (sig-nal) can be multi-scale refined by dilation and translation of mother wavelet step by step, with the final breakdown of time at high frequency, breakdown of frequencies at low frequency. This method can be focused to any of the details of the signal. There-fore, the algorithms for digital watermarking based on wavelet transform has become a current research focus and an important direction research on digital watermarking.This dissertation, image digital watermarking algorithms based on wavelet trans-form are discussed, and a series of results are obtained.Firstly, development of wavelet analysis, wavelet transform theory, mu-ltiresolution analysis, wavelet decomposition and reconstruction of digital image are outlined. Dig-ital image watermarking basic knowledge, performance evaluation criteria and some classical digital watermarking algorithms are recalled.Secondly, digital image watermarking algorithm based on wavelet transform is researched. A method of combining Arnold transform with logistic chaos to scram-bling digital watermarking, digital watermarking algorithms based on haar wavelet and Daubechies wavelet respectively. Through aggressive testing, complete the all wa-termark system testing of invisibility and robustness. Finally, relevant conclusions are obtained.