A Combined And Blind Watermarking Scheme Based On The Lifting Wavelet Transformation And ECC

Internet has become a main way for us to get information along with the widely use of network and the applications of multimedia technology. Nowadays, digital information products can be distributed via the World Wide Web to a large number of people in a cost efficient way and people can easily get these through Internet. The digital information can be easily duplicated and revised. These characters of digital media, however, bring a new challenge in applications. How to protect the benefits of the owner of the digital information products becomes the first imperative problem to resolve. Digital watermarking technology plays an important role for copyright protection;it allows embedding an imperceptible or perceptible mark (for example, embedded fingerprinting and digital signature information) in multimedia data to identify the owner copyright.Since the traditional coding technology for image and video is using of DCT, the blocked and whole DCT technology in frequency domain was used in order to embed watermarking. However the wavelet transformation has some advantages better than DCT, it can be used as both image compression and watermarking embedding. Because of the standardization process of JPEG2000, we think it is imperative to consider the wavelet transform domain for watermarking embedding.After studying and analyzing the disadvantages of the previous algorithms in digital watermarking, we focus our work on the researching and implementation of the combining watermarking technology. The main idea of the combining watermarking is that the watermarking information is embedded into the high frequency section and the low frequency section of the wavelet domain respectively. So the watermarking will have different characters: robustness and fragile.There are totally five chapters in this paper. In chapter one, we will try to motivate the research effort in watermarking and discuss some applications. The "watermarking problem" is also introduced in chapter one and we analyses why it is hard to design watermarking algorithms that it can fulfill the requirements derived in this chapter. In chapter two, I mainly introduced the theory of watermarking, including the general model of digital watermarking in discrete wavelet transformation domain, and several typicalalgorithms. In chapter three, the wavelet analyses will be introduced, especially the lifting wavelets transform. In this section, we explain why we choose the technology based on discrete wavelet transformation rather than other transformation methods to embed watermarking. In chapter four, I introduced the technology of ECC and random permutation. In chapter five, an improved combined watermarking scheme for image authentication and protection is proposed: A Combined and Blind Watermarking Scheme Based on the Lifting Wavelet Transformation and ECC. Finally, I simulate and implement the algorithm by computer. Comparing with the primary paper, the ability to resist all kinds of tamper is improved. Meanwhile, besides telling you whether an image has been tampered, the fragile watermark can reflect the distortion status truly and intuitively.