基于无损压缩的加密图像可逆信息隐藏

Reversible data hiding in encrypted images based on lossless compression

针对现有方法存在的隐藏容量低、操作不灵活的缺陷,文章提出了一种基于无损压缩的加密图像可逆信息隐藏算法。图像拥有者对原始图像进行替换加密;秘密信息隐藏者将加密图像随机划分为若干个大小相等且互不重叠的块,并且在每个加密块中采用无损压缩技术获得空余空间来隐藏秘密信息;接收者采用提取密钥进行秘密信息提取后,再结合解密密钥能够正确恢复出原始图像。实验仿真结果表明,与现有方法相比,所提出的算法在峰值信噪比和信息隐藏率上都具有很好的效能。

Aiming at the defects of existing algorithms in the embedding capacity and the operation of receiver, an algorithm of reversible data hiding in encrypted images based on lossless compression is proposed. Firstly, the substitution encryption technology is used to encrypt the original image. Secondly, the data hider randomly divides the encrypted image into several equal and non-overlapping blocks, then the ones are compressed with a lossless manner to create a sparse space to embed secret data. Finally, the receiver can obtain secret data and original image by using the data-hiding key and decryption key. The experimental results show that compared with the previous methods, the proposed method achieves excellent efficiency in peak signal-to-noise ratio（PSNR） and embedding rate.