Wavelet-based self-similar watermarking for still images

This paper presents a wavelet-based watermarking method for copyright protection of still images. Watermarks are structured in such a way to attain spatial self-similarity with respect to a cartesian grid. Embedding and detection are performed in the wavelet domain thus allowing multiresolution detection. The novelty of the current approach is the use of self-similar watermarks (quasi scale-invariant), which are expected to be robust against geometric transformations, especially scaling. The approach proves rather efficient against many kinds of distortions, such as linear and nonlinear filtering, JPEG compression, scaling, cropping and rotation