中文摘要：

根据图像离散余弦变换频谱图特征及结合人眼对亮度和颜色的对比度敏感视觉特性,提出了一种人眼感知图像最小误差即JND阈值的计算方法,通过计算出的JND阈值,提出了一种基于YCrCb颜色空间的彩色图像水印技术方案。方案依据JND阈值筛选彩色图像的3个分量亮度图变换域频谱系数来进行水印的嵌入和提取。从水印技术方案上看,JND阈值的引入使得水印的嵌入达到最大;嵌入算法使得水印嵌入的位置具有随机性,有力地保证了水印信息的安全性。仿真实验和攻击测试表明：含水印图经压缩攻击后的图像与原始图像基本一样,提取的水印信息与原始水印基本相同;攻击后的含水印图具有较好的透明性和较高的鲁棒性。提出的基于YCrCb颜色空间和人眼视觉特性的彩色图像水印技术方案,是一种可行的、较好的彩色图像技术。

英文摘要：

According to the characteristics of discrete cosine transform spectrum images and the characteristics of contrast sensitivity of human vision system to brightness and color,a method was proposed to calculate a minimum error of human eye perceiving images which was JND threshold namely.By calculating the JND threshold,a color image watermark technology program was proposed based on YCrCb color space.According to JND threshold,matrix coefficients of the spectrum images of three components brightness images of color image were filtered to carry out embedding and extracting watermark.From watermarking technology program,JND threshold made the watermark embedded into the maximum.Embedded watermark algorithm made the position embedded watermark random,which effectively ensured the security of watermark information.Simulation experiments and attacks tests result showed that the compressed images which were embedded watermark were basically the same with the original image;the extracted watermark is basically the same with original watermark information;the images embedded watermark after attack has good transparency and high robustness.It was concluded that the proposed color image watermark scheme based on YCrCb color space and human visual system characteristics is a feasible and better color imaging technology.