光学学报, 2009, 29 (12): 3310, 网络出版: 2009-12-23
基于相位恢复的傅里叶变换全息图像数字水印
An Image Digital Watermarking with Phase Retrieval Algorithm and Fourier Transformation Hologram
信息光学 信息隐藏 数字水印 相位恢复算法 数字全息 information optics information hiding digital watermarking phase retrieval algorithm digital holography
摘要
提出了一种新的基于信息光学的图像数字水印方法。该方法采用相位恢复算法将需要隐藏的水印图像编码为纯相位,然后用该纯相位代替传统傅里叶变换全息中的物光波频谱与参考光波发生干涉,得到理论对比度为100%的傅里叶变换全息图。采用密钥将此全息图进行加密,并通过离散余弦变换在频域嵌入宿主图像中完成水印信息的嵌入。水印提取时需先用密钥将提取的全息图进行解密,再进行光学或数字全息再现即可完成。理论分析和数值计算实验表明,该水印技术对有损压缩、剪切和滤波等多种图像处理操作均具有很高的稳健性,比传统傅里叶变换全息水印的稳健性有很大提高,具有很好的实用价值。
Abstract
A new approach of digital watermarking based on information optics is proposed. The watermarking image is transformed into virtual object wave after phase retrieval algorithm. Then use the virtual object wave to take the place of traditional Fourier-transformed object wave. It interfered with the reference wave to form Fourier-transformed digital hologram and the contrast is 100% in theory. Hologram is embedded into host image by discrete-cosine-transform and encrypted by security key. It can be extracted with the security key. The watermark is retrieved by reconstruction of optical or digital holography. Theoretical analysis and numerical experiments show that the algorithm has more robustness and practical value to image lossy compression,cropping and filter,comparing with the algorithm based on general digital holography.
陈大庆, 顾济华, 周皓, 姜锦虎. 基于相位恢复的傅里叶变换全息图像数字水印[J]. 光学学报, 2009, 29(12): 3310. Chen Daqing, Gu Jihua, Zhou Hao, Jiang Jinhu. An Image Digital Watermarking with Phase Retrieval Algorithm and Fourier Transformation Hologram[J]. Acta Optica Sinica, 2009, 29(12): 3310.