On the evaluation of wavelet filter banks for wavelet-based image watermarking - case of correlation-based watermarking methods

摘要

The digital watermark technology is now drawing attention as a useful method of protecting copyrights of digital contents such as audio, image, and video. Especially, efficient image watermarking methods have been developed in the DWT (discrete wavelet transform) domain. In the wavelet-based watermarking, similar to the wavelet-based coding, the choice of wavelet filter banks generally affects the performance of watermarking methods. Hence a natural question arises for the wavelet-based watermarking: what is the best wavelet filter bank for use? In the preceding paper, we have evaluated wavelet filter banks used in the quantization-based watermarking methods theoretically from the viewpoint of the quality of watermarked image and the robustness of watermark, and given a solution to the 'best wavelet filter bank' problem. In this paper, we discuss the 'best wavelet filter bank' problem for the correlation-based watermarking methods with the same approach as in the preceding paper.