Research On Robust Digital Watermarking Algorithm Based On Redundant Discrete Wavelets And Schur Decomposition

Specific to the problem of low robustness,small capacity and slow running speed of blind watermarking algorithm,a robust digital watermarking algorithm based on Redundant Discrete Wavelet transform and Schur decomposition is proposed in this paper.The algorithm will be secondary RDWT transform to extract the approximation image subgraph low frequency part,and will block after each piece of low frequency coefficient of Schur decomposition,through modifying the maximum energy element on the diagonal line in the upper triangular matrix after decomposition of each block to complete the embedding of the watermarked image encrypted by Fibonacci transform,watermark extraction process of the realization of the aim of the blind extraction.The experimental results showed that the watermarking algorithm is only 0.97 s,at the same time,the average watermark is 0.211 s.Compared with the similar blind watermarking algorithm,the PSNR value increased by 14.12%.Compared with similar blind watermarking algorithms,the attacks of gaussian noise,salt and pepper noise attack and shear geometry attack increased by 21.32%,17.31% and 27.83% respectively.Using the same scale as the carrier image to ensure the watermarking algorithm's capacity.The results of using RDWT under each level of decomposition,using the sampling mechanism to keep it to time shift invariance,thus effectively overcome the Discrete Wavelet Transform,transfer variant shortcomings,to ensure the robustness of the algorithm and capacity,especially in shear attack.Fibonacci transform encryption technology makes the watermark information dispersed in carrier image,to extract the watermark information will not be a large distortion phenomenon.Moreover,Schur decomposition has its own characteristics of interference and computational time complexity,which further guarantees the robustness of the algorithm and improves the operation speed of the algorithm.