Research On Color Image Watermarking Algorithm Based On DWT Domain

The development of computer technology makes the multimedia products become easy to spread,which brings another problem: copyright protection.Due to illegal copying privacy is becoming more and more serious,digital products copyright ownership and protection need to be solved.So far,the most wide and reliable solution of copyright protection is digital watermarking technology.Digital watermarking technology is important branch of information hiding technology.It inherits the advantages of traditional cryptography and makes up its disadvantages.And the current research focus and hot spot is digital watermarking technology.The basic theory of digital watermarking technology is introduced,which includes the development background of the watermark,the research purpose,the concept and classification of watermarking and so on.A watermarking algorithm based on biorthogonal wavelet transform and HVS feature is proposed.Compared with the favor of orthogonal in digital watermarking,the article chose to birorthogonal wavelet.The biorthogonal wavelet made a sacrifice in orthogonality,but gaining the linear phase which means digital watermarking system would avoid distortion in some extent.So the biorthogonal wavelet had the advantages of compact support,orthogonality and symmetry.It had more advantages than the orthogonal wavelet in the field of digital watermarking.The watermark embedding area selection scheme has been improved,choosing the intermediate frequency image after the wavelet decomposition as embedded area.There is good transparency in the low frequency sub image,and good resistance in the high frequency sub image.Most watermarking algorithms only considered the transparency or robustness,in low or high sub image to embed the watermark.The article did better trade-off between transparency and robustness,so chose the low and middle sub image as the embedded area.The experimental simulation method is used to verify the performance of the proposed watermarking algorithm,and the data obtained are analyzed and compared to determine the need to improve the algorithm in this paper.Digital watermarking algorithm is proposed in this paper for improvement of domain watermarking algorithm.The proposed algorithm improves its robustness and expands the scope of application of watermarking technology,at the same time provides the technical support for copyright protection of color images.