SECURE WATERMARKING BASED ON SVD AND WAVELETS

Protection of digital multimedia content has become an increasingly important issue for content owners and service providers. As watermarking is identified as a major technology to achieve copyright protection, the relevant literature includes several distinct approaches for embedding data into a multimedia element. Because of its growing popularity, the Discrete Wavelet Transform (DWT) is commonly used in recent watermarking schemes. In a DWT based scheme, the DWT coefficients are modified with the data that represents the watermark. In this paper, we present a hybrid scheme based on DWT and Singular Value Decomposition (SVD). After decomposing the cover image into four bands, we apply the SVD to middle frequency band, and embed the same watermark data by modifying the singular values. Nine families of wavelets, both orthogonal and bi-orthogonal, are compared for efficiency. To objectively measure the success of the algorithm and the influence of the mother wavelet, the PSNR for each wavelet family and image is obtained.