An Improved Robust Watermarking Scheme Based On PDE Decomposition

With the rapid development of Internet technology and digital signal processing technology, digital products have been widely popular and how to protect digital products effectively has become today’s necessary elements for information security in nowadays. Since the 1990 s, digital watermarking technology is an effective means of information security and highly valued by many scholars and researcher. This paper describes the current situation and development prospects of domestic and foreign research of digital watermarking, elaborated classification of digital watermarking, typical digital watermarking algorithm, common types of attacks and designs and realization of watermark.This paper presents an improved robust watermark algorithm based on PDE decomposition.In this paper,we firstly take advantage of the logistic chaos mapping to encrypt the watermark image and divide the encrypted watermark image into two parts.Then PDE is used to decompose the host image into cartoon and texture components. And then, DWT and SVD are selected to handle cartoon and texture respectively according to the complexity of these two parts. Lastly the two watermark images are respectively embedded into the low frequencies of DWT and the singular value matrix of SVD. Experiments show that the scheme proposed can efficiently enhance not only transparency,but also robustness for some conventional watermark attacks such as JPEG compression,Gaussian noise,rotation and so on. The main research contents and and innovation is as follow:Firstly, we use TV-G total variation model to decompose the the host image. the energy of the noise part is small and easy to lose part of the watermark.In order to improve the robustness of watermarking algorithm and transparency, the host image is decompose into cartoon and texture part, rather than three parts:cartoon, texture and noise.Secondly, PDE combined with DWT and SVD is applies to improve performanceof the digital watermarking algorithm based on the PDE. On the one hand, DWT was chose to deal with cartoon part instead of DCT(Discrete Cousin Transform). On the other hand, the singular value is an inherent attribute of the image matrix that has a very good stability.the watermark embedded into the singular value in the sequence algorithm has better robustness and after SVD is conducted to texture part.Thirdly, we summarized several kinds of digital watermarking algorithms based on PDE, and analyzed the merits and drawbacks of these watermarking algorithms.Finally,to enhance the robustness and security,we use the Logistic mapping basic that is applied to watermarking algorithm based on PDE.To a certain extent, reducing the impact to the human visual by logistic chaos mapping enhances the transparency the watermarking algorithm.