基于块重构的加密域可逆信息隐藏

提出了一种基于块重构的加密域可逆信息隐藏方法。首先使用一种特定的加密方法对原始图像块进行加密,其中包括置乱和块重构,该方法能够有效地将冗余从最高有效位转移到最低有效位;其次将位平面划分为不重叠的均匀块和非均匀块,通过标签图对这两种类型的图像块进行区分及记录;最后在可嵌入信息的均匀块中嵌入相关辅助数据,并将秘密信息嵌入到剩余的可用块中。基于加密密钥和数据隐藏密钥的可用性,接收端能够可分离地实现准确提取所嵌入的数据以及无损地恢复原始图像。实验结果表明,该方法在一定程度上提高了信息嵌入量和直接解密图像的解密质量。

Reversible Data Hiding in Encrypted Domain with Block Rearrangement

We propose a reversible data hiding scheme in encrypted domain based on block rearrangement in bit plane. Firstly, specific encryption methods, including scrambling and block rearranging, are applied to encrypt an original image. Secondly, scrambled bit planes are divided into non-overlapping blocks, including homogeneous blocks and nonhomogeneous blocks, and a label map is generated to identify these two kinds of blocks. Thirdly, after embedding necessary auxiliary data into embedded homogeneous blocks, data hider can embed additional data into the remaining available blocks. Based on the availability of encryption key and data hiding key, receivers can realize separable operations of data extraction efficiently and image recovery losslessly. Experimental results demonstrate that the proposed scheme gains improvement both in embedding capacity and in the quality of decrypted image.