Blind Watermark Algorithms Based On HVS In DCT Domain

In this paper we introduce a well-known chaotic system "tent-map", showing that "tent-map"can generate series having character as Gauss White Noise series. After that we recommend some results of Human Visual System and show the use of them in digital watermark technology. Then we introduce the formulas of DCT transform By virtue of above results, two blind watermark Algorithms based on HVS in DCT domain are proposed in this paper. In these algorithms, chaotic system"tent-map"is used to generate two chaotic sequence as a key of embedding . All works are done in DCT domain. For the higher robustness, we use the theory of HVS to decide the embedding strength under low distortion. Two blind watermark algorithms are testified both show good performance. The robustness and invisibility of watermark are improved obviously.