Design and implementation of improved watermarking system in WT domain  

作　　者：ZHANG Deng-yin CHEN Jia-ping SUN Jun-cai 

机构地区：[1]Institute of Digital Processing and Transmission, Nanjing University of Posts s, Nanjing 210003, China

出　　处：《The Journal of China Universities of Posts and Telecommunications》2007年第2期58-63,共6页中国邮电高校学报（英文版）

基　　金：the National Natural Science Foundation of China （60573141）; the Hi-Tech Research and Development Program of China （2004AA775053, 2005AA775050）; the High Technique Research Plan of Jiangsu Province （BG2005037); The Six Heights of Talent Program of Jiangsu Province.

摘　　要：This article presents a watermarking algorithm based on one-dimensional （1-D） chaotic map in wavelet transform （WT） domain. Traditional encryption and watermarking technologies in the WT domain are combined in this algorithm. First, the watermark is encoded by a chaotic sequence, which is generated by a key. On the basis of human visual system （HVS）, it is then divided into two parts and embedded into the low- and intermediate-frequency bands of three-layer WT domain. The encryption of the watermark and the choice of embedded areas based on the perceptivity not only confer the watermark with good invisibility but also with good robustness. Meanwhile, it is difficult to decrypt the watermark extracted from the WT domain.This article presents a watermarking algorithm based on one-dimensional （1-D） chaotic map in wavelet transform （WT） domain. Traditional encryption and watermarking technologies in the WT domain are combined in this algorithm. First, the watermark is encoded by a chaotic sequence, which is generated by a key. On the basis of human visual system （HVS）, it is then divided into two parts and embedded into the low- and intermediate-frequency bands of three-layer WT domain. The encryption of the watermark and the choice of embedded areas based on the perceptivity not only confer the watermark with good invisibility but also with good robustness. Meanwhile, it is difficult to decrypt the watermark extracted from the WT domain.

关 键 词：WATERMARKING chaotic map WT INVISIBILITY ROBUSTNESS 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]