A semi-blind digital watermarking scheme based on singular value decomposition

This paper presents a robust watermarking approach for hiding grayscale watermarks into digital images. Plugging the codebook concept into the singular value decomposition (SVD), the proposed method embeds the singular values (SVs) of the original image into the watermark one to attain the lossless objective. The experimental results show that the proposed scheme guarantees the extracted watermark on an average and the worst PSNR values of 24.91 and 19.96 dB, respectively. In addition to the guarantee of the quality of extracted watermark image, the security of the referenced watermark is further strengthened by applying chaos permutation on it in advance. The proposed scheme leads to satisfactory robustness to various attacks and is compared to other well-known grayscale watermarking methods to reveal its efficiency for practical applications.