A watermarking algorithm for digital image based on logistic and SVD

A novel watermarking algorithm for digital image based on logistic and SVD is proposed in this paper. Firstly, chaos map is applied in this algorithm. The proposed scheme uses chaotic sequence twice: first to disorder the original mark; second to resolve the distortion in the diagonal. Simulation results prove that the correlation coefficient between the disordered and the original mark is small. If the initial value of chaos is unknown, the characteristic watermarking can not be extracted correctly. Secondly, read larger coefficients in diagonal Block-SVD by the order to create matrix as the same size as the watermarking images, which not only enhance the capacity of embedded information but also survive a variety of geometry attacks. Experimental results show that the new watermarking scheme has a good transparence of embedded watermark image and is robust against attacks such as adding noise, filtering, JPEG compression and geometric distortion.