A Pyramid-Based Watermarking Technique for Digital Images Copyright Protection Using Discrete Wavelet Transforms Techniques

With the growth and advances in digital communication technologies, digital images have become easy to be delivered and exchanged. These forms of digital information can be easily copied and distributed through digital media. These concerns motivated significant re‐ searches in images watermarking [1]. New progress in digital technologies, such as com‐ pression techniques, has brought new challenges to watermarking. Various watermarking schemes that use different techniques have been proposed over the last few years [2-10]. To be effective, a watermark must be imperceptible within its host, easily extracted by the own‐ er, and robust to intentional and unintentional distortions [7]. In specific, discrete wavelet transforms (DWT) has wide applications in the area of image watermarking. This is because it has many specifications that make the watermarking process robust. Some of these specifi‐ cations are [4]: Space-frequency localization, Multi-resolution representation, Superior Hu‐ man Visual system (HVS) modeling, and adaptively to the original image. A wavelet-based watermarking technique for ownership verification is presented by Y. Wang [11]. It uses or‐ thonormal filter banks that are generated randomly to decompose the host image and insert the watermark in it.