基于虚拟光学信息隐藏理论提出了一种三维空间数字水印算法1 该数字水印算法能成为

一种多媒体数据产权保护的有效方案1 对算法的测试结果表明,该算法对于噪音叠加、剪切、旋转、

有损压缩等常见的图像处理操作具有较高的鲁棒性1 由于引入了虚拟光学信息隐藏思想,将虚拟

光路的几何结构参数作为密钥,设计出了多重“锁”和多重“密钥”1 随机模板编码技术的引入,更进

一步提高了数字水印系统的密钥空间. 仿真实验结果表明该算法具有很好的安全性1-　A new approach to digital watermarking in three2dimensional (32D) space based on virt ual2optics

and random mask encoding is presented. The watermarking algorithm can offer an effective solution to t he

issue of copyright protection of multimedia data dist ributed via t he communication channel . The result s

show t hat t he embedded watermark is robust to normal data manip ulations , such as adding noise ,

cropping , rotation , and J PEG compression. Because t he design concept and met hodology based on

geomet ric parameter s of Virt ual2Optics was adopted , t he proposed 32D watermarking system has good

security. There are large degrees of f reedom existing for designing a security lock ( s)/key ( s) , including

multiple lock ( s)/key ( s) and multi2dimensional lock ( s)/key ( s) . Numerical experiment s are performed to

validate the p roposed met hod , and sensitivities of some parameter s are quantitatively analyzed and

illust rated. The possible dimensions of keys are ro