Color Image Watermarking Algorithm Based on DWT-SVD

Abstract

A novel watermarking scheme of embedding a scrambling watermark into the green component of the color image based on DWT-SVD is proposed. The green component is decomposed for LL <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , HL <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , LH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , HH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> with DWT at the Nth levels. For each subband, adopt different methods to complete the watermark embedding. For the part LL <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , imbed pseudo-random after spreading according to the energy. Decompose the three wavelet matrix coefficients LH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , HL <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , HH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> with SVD. Add the SVD of the scrambled watermarking and the SVD of the wavelet coefficients, and then the imbedding course is accomplished. The retrieving watermark algorithm and the blind detecting algorithm both are designed according to the embedding scheme. The experiment indicates that the watermark is robust to JPEG compression, cropping, Gaussian noise, median filter and resize.