关键词: 人类视觉系统, 离散小波变换, JND门限, 鲁棒性

Abstract:

A robust image watermarking algorithm based on Human Visual System（HVS） and Discrete Wavelet Transform（DWT） is proposed.Host image is decomposed through the discrete wavelet transform.The JND threshold is calculated according to the human visual system characteristics，and the significant coefficients of wavelet are selected.Watermark image is embedded to the different frequency of the significant coefficients of wavelet.And watermark image is embedded by the rule of the improved binary operation，changing wavelet coefficients part of the decimal to improve the quality of the image after the watermark embedded.The experimental results show that the proposed algorithm has enhanced the robustness effectively under the premise of guaranteeing watermark invisibility，and it is robust against JPEG compression，additive noise，zooming，cut and median filtering attack.

Key words: Human Visual System（HVS）, Discrete Wavelet Transform（DWT）, Just Noticeable Difference（JND） threshold, robustness