Study On Algorithm For Image Digital Watermarking

It is well-known that pirating problem is becoming more and more serious with multimedia technology developing, so protecting copyright is more important. Digital watermarking technology provides a new method. More and more people pay attention to it, or show s lot of interest. And this technology is studied and used widely. So study of the algorithm for digital watermarking becomes hotspot.This paper analyses basic principle of digital watermarking technology and basic model of digital watermarking system. And the attributes, classing and applying matter of digital watermarking technology is presented in a nutshell. Some typical algorithms and performance is analyzed. Then three algorithms based on DCT are carried out. At the same time the performance of watermarking from these algorithms are proved through attracts like image processing, compressing, cutting and adding noise.A coefficient property digital watermarking algorithm is studied, the shortcomings are analyzed, and improving way is presented. The result is that doubling watermarking size, improving the ability of resisting cut and compress, enhancing robustness of the algorithm. At last, the advantage is proved through simulation. In addition, shortage of improving method is analyzed. A digital watermarking algorithm based on HVS is given.A new idea is proposed, which is that image decomposition is applied to digital watermarking algorithm. Many parameters that value watermarking performance are recorded from simulation. Comparing with previous algorithm, the applying of the idea does not enhance robustness and invisible. We have to find out the reason in the future. After all, this idea provides a new way to study digital watermarking.