Translator Disclaimer
19 May 2008 A new watermarking method based on the use of the hyperanalytic wavelet transform
Author Affiliations +
Watermarking using pixel-wise masking in the wavelet domain proves to be quite robust against common signal processing attacks. Initially, in a system proposed by Barni et al., embedding is made only in the highest resolution level; there are two disadvantages to this technique: the watermark information can be easily erased by a potential attacker and embedding in the DWT is susceptible to geometric attacks, such as shifting. To enhance this watermarking method, we use a modified perceptual mask that models the human visual system behavior in a better way, previously proposed by the authors. The texture content is appreciated with the local standard deviation of the original image, which is further compressed in the wavelet domain. Since the approximation image of the coarsest level contains too little information, we appreciate the luminance content using a higher resolution level approximation sub-image. To increase the capacity of the watermarking scheme the embedding is made in the HWT domain, using two strategies: in the real parts of the HWT coefficients and in the absolute value of the HWT coefficients of the original image. The implementation of the HWT is made using a new technique, recently proposed by the authors. Moreover, we make use of all the levels except the coarsest one, for attack resilience. We use three types of detectors that take advantage of the hierarchical decomposition. Tests were made for different attacks (JPEG compression, median filtering, resizing, cropping, gamma correction, blurring, shifting and addition of white Gaussian noise), that prove the effectiveness of perceptual watermarking in the HWT domain.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Corina Nafornita, Ioana Firoiu, Jean-Marc Boucher, and Alexandru Isar "A new watermarking method based on the use of the hyperanalytic wavelet transform", Proc. SPIE 7000, Optical and Digital Image Processing, 70000W (19 May 2008);

Back to Top