Research On Parameter Adaptive Image Watermarking Algorith

As one of information hiding technology,digital watermark plays a key role in solving the problem of copyright infringement of image information in network communication.Its principle is to embed secret information into the target source,so that it can withstand a variety of common attacks and still be completely extracted without losing its own meaning.Although digital watermarking technology has incomparable advantages in data ownership certification,in the process of practical application,digital watermarking still has the problem that the embedding parameters are difficult to set adaptively,and it is difficult to adapt to the needs of multi-party copyright sharing.To solve the problem,this paper uses Wang-Landau(WL)sampling and layout evolution strategy(layout evolution strategy,LES)to adaptively adjust the embedding strength parameters and embedding position parameters in image digital watermarking,and studies embedding strength optimization watermarking method and embedding position optimization multiple watermarking method to reconcile watermarking performance and ensure legal rights of image data copyright co-owners.The main research content of this paper is as follows:(1)In this research,an adaptive image watermarking method based on discrete wavelet transform(DWT),singular value decomposition(SVD)and Wang-Landau(WL)sampling is proposed to balance between robustness and imperceptibility by adaptively setting the embedding strength.The three-level approximate subband obtained by applying the three-level transform to host image is used to embed the watermark image after performing the singular value decomposition.The Wang-Landau sampling method aims to adaptively adjust the embedding intensity through the target evaluation function and historical experience to improve the global optimization ability of the algorithm.Finally,a variety of image attack methods are applied to verify the performance of the proposed method,and the test results of image quality test and watermark robustness are given.This method achieve higher robustness and make the invisibility meet the established threshold compared with other watermarking methods.(2)In order to meet the needs of multiple owners to share copyright,a layout evolution strategy(LES)based on an improved strategy of tabu search(TS)is proposed to adaptively search for the optimal embedding positions of multiple watermarks,and then use local images to extract these watermarks.This method starts from the multi-watermark layout in any initial state,through global-local search,continuously updates the current neighbor layout and adaptively adjusts the parameters in the search to obtain the optimal embedding position of multiple watermarks,and the position information will be used as the key Distributed to watermark owners so that these watermarks can be extracted through key information.Finally,the algorithm is tested experimentally,and it is found that the method can make the watermarked image have higher invisibility and improve the robustness of multiple embedded watermarks,which proves that the strategy can be effectively and flexibly adapted to various watermarks and carriers image to generate the corresponding optimal layout.