Wavelet filter evaluation for image watermarking

Efficient image watermarking techniques have been developed in the wavelet domain. Similar to other wavelet-based image processing, the choice of wavelet filters generally affects the performance of a wavelet-based watermarking system. In this paper, we evaluate the performance of a set of biorthogonal integer wavelets under a multiresolution-watermarking framework. Biorthogonal integer wavelets have been extensively used for image applications because they possess the linear-phase property and can be efficiently implemented. We find that the widely adopted 9/7-F wavelet achieves the best robustness performance. Further investigation is conducted to show that the superiority of the 9/7-F wavelet is primarily owing to its being nearly orthogonal.