一种基于二元位相加密的大信息量数字全息水印

研究了一种基于二元位相加密的大信息量数字全息水印方法，对需隐藏的水印信息用二元位相编码，然后再用2台阶位相密钥进行加密，作为水印插入宿主图像中，解码后得到了高质量的水印结果.与平面波照明数字全息水印相比，采用位相密钥数字全息水印有效地提高了水印提取的安全性和相对光学效率，并保持了对大信息量水印的提取质量，解码过程不依赖于原图像. 计算和分析了二元位相密钥的空间分布对水印信息提取质量的影响，计算结果验证了理论的正确性.

A Digital Hologram Watermarking with Large Information Contents Based on Binary Phase Encryption Method

A digital hologram watermarking with a phase encryption feature is proposed based on a binary optical phase retrieval algorithm. The watermark has been encoded with the binary optical phase algorithm and encrypted with a binary phase key. Comparing to the digital hologram watermarking with binary phase structure under the plane illumination, the security of the proposed method is greatly improved by using a binary phase key while the quality of decrypted watermark with large information contents is almost maintained unchanged. The decrypting processing is independent of original host image. The quality of decrypting watermark under the different sizes of encryption keys has been discussed. The simulation results prove the theoretical analysis.