CAJ | 학술논문

提出一种基于分数傅里叶变换和随机相位编码的光学加密数字水印技术,可成为一种信息隐藏及保护的有效方案.该数字水印技术对于噪音叠加和常见的图像处理操作具有较强的稳健性.该技术根据光学级联分数傅里叶变换系统,利用两个随机相位分布函数对水印信息编码并经过迭代分数傅里叶变换嵌入到变换域的载体图像中.在水印检测和提取过程中,两个相位分布函数作为密钥.随机相位编码技术的引入,进一步提高了数字水印系统的密钥空间.增强了系统的安全性.该数字水印技术基于光学分数傅里叶变换原理,可以利用光学变换系统方便地实现.
제출일충기우분수부리협변환화수궤상위편마적광학가밀수자수인기술,가성위일충신식은장급보호적유효방안.해수자수인기술대우조음첩가화상견적도상처리조작구유교강적은건성.해기술근거광학급련분수부리협변환계통,이용량개수궤상위분포함수대수인신식편마병경과질대분수부리협변환감입도변환역적재체도상중.재수인검측화제취과정중,량개상위분포함수작위밀약.수궤상위편마기술적인입,진일보제고료수자수인계통적밀약공간.증강료계통적안전성.해수자수인기술기우광학분수부리협변환원리,가이이용광학변환계통방편지실현.
A novel digital watermarking method by optical cascaded fractional Fourier transform and random phase encoding is proposed. This method can be served as an effective way of information hiding and protection. Experimental results show that this watermarking method has strong robustness against noise, shearing, rotation, resizing, and medium filtering. This watermarking method is based on optical cascaded fractional Fourier transform system. The watermark information is iterative fractional Fourier transformed and embedded into host image. And two phase distributions can be obtained as keys to protect the watermark information. With the introduction of double phase encoding, the key space of this watermark system is greatly enlarged. As a result the security of this watermark system is enhanced. This watermark technique can be implemented both optically and digitally.