Research On Blind Watermarking Of Double Color Images Based On DNA Sequences And DWT

With the rapid development of the Internet science,security issues and copyright protection issues of digital products has become prominent increasingly,the digital watermarking technology has played an important role in solving the above problems.Digital watermarking is a technique that inserts the information into the original data of digital product,in order to achieve the purpose of protection the copyright of the digital products.Therefore,the study of the digital watermarking technology has been highly regarded by the academics.In this paper,we introduct the watermarking technology briefly,aiming at the research of color image watermarking algorithm and in order to realize the blind watermaking extraction,we design the watermarking algorithm based on matrix decomposition and chaos to realize the watermark embedded and extraction.The main research of this thesis is as follows:1.A double color image watermarking scheme based on DNA and QR is proposed.Firstly,the color watermark image is encrypted by DNA and CML,secondly,the color host image is divided into 4x4 non-overlapping pixel blocks,and QR is performed on each selected pixel block to get the matrix R.Thirdly,the DNA sequences encrypted watermark is embed into the host image by modifying the matrix R.The watermark can be extracted from the watermarked image without resorting to the host image and the original watermark.Experimental and analysis show that the watermarking scheme has not only better imperceptibility but a strong robustness.2.A double color image watermarking scheme based on 2D-DWT and SVD is proposed.In order to improve security of the algorithm,we use CML to encrypt the original watermark.The host image and the encrypted watermark are converted into NTSC color space,then the 2D-DWT is performed on the host image,and the encrypted watermark is embedded by modifying the singular values of the low frequency sub-bands of the host image.Experimental and analysis show that the proposed watermarking scheme has not only an excellent imperceptibility but also a strong robustness against the common image processing attacks,geometric attacks and some composite attacks.