Robust Watermarking with Kernels-Alternated Error Diffusion and Weighted Lookup Table in Halftone Images  

作　　者：Jing-Ming Guo 

机构地区：[1]with the Department of Electrical Engineering, National Taiwan University of Science and Technology

出　　处：《Journal of Electronic Science and Technology》2011年第4期306-311,共6页电子科技学刊（英文版）

基　　金：supported by National Science Council under Grants No. NSC 99-2631-H-011-001

摘　　要：A halftone watermarking method of high quality, robustness, and capacity flexibility is presented in this paper. An objective halftone image quality evaluation method based on the human visual system obtained by a least-mean-square algorithm is also introduced. In the encoder, the kernels-alternated error diffusion （KAEDF） is applied. It is able to maintain the computational complexity at the same level as ordinary error diffusion. Compared with Hel-Or using ordered dithering, the proposed KAEDF yields a better image quality through using error diffusion. We also propose a weighted lookup table （WLUT） in the decoder instead of lookup table （LUT）, as proposed by Pei and Guo, so as to achieve a higher decoded rate. As the experimental results demonstrate, this technique is able to guard against degradation due to tampering, cropping, rotation, and print-and-scan processes in error-diffused halftone images.A halftone watermarking method of high quality, robustness, and capacity flexibility is presented in this paper. An objective halftone image quality evaluation method based on the human visual system obtained by a least-mean-square algorithm is also introduced. In the encoder, the kernels-alternated error diffusion （KAEDF） is applied. It is able to maintain the computational complexity at the same level as ordinary error diffusion. Compared with Hel-Or using ordered dithering, the proposed KAEDF yields a better image quality through using error diffusion. We also propose a weighted lookup table （WLUT） in the decoder instead of lookup table （LUT）, as proposed by Pei and Guo, so as to achieve a higher decoded rate. As the experimental results demonstrate, this technique is able to guard against degradation due to tampering, cropping, rotation, and print-and-scan processes in error-diffused halftone images.

关 键 词：Error diffusion halfloning lookup table watermarking. 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术] TN873.94[自动化与计算机技术—计算机科学与技术]