In this paper, a high-capacity reversible data hiding (RDH) scheme for encrypted images with separability is proposed. The image is first divided into non-overlapping blocks, and each block is encrypted with the same random value. The advantage is that the correlation between adjacent pixels can be preserved. Utilizing the preserved correlation, the prediction difference in encrypted domain is exactly the same as that of plaintext domain, so that the separability can be achieved. Without accessing the original image content, the data-hider can embed additional data into encrypted image through histogram shifting and difference expansion. At the receiving end, the embedded additional data and the original image can be recovered without any error in separable manner. Experimental results are presented to demonstrate the feasibility and efficiency of the proposed scheme.

本文提出了一种具有可分离性的加密图像大容量可逆数据隐藏（RDH）方案。首先将图像划分为不重叠的块，并使用相同的随机值对每个块进行加密。优点是可以保留相邻像素之间的相关性。利用保留的相关性，加密域中的预测差异与明文域中的预测差异完全相同，从而可以实现可分离性。在不访问原始图像内容的情况下，数据隐藏者可以通过直方图移位和差异扩展将其他数据嵌入加密的图像中。在接收端，可以以可分离的方式恢复嵌入的附加数据和原始图像而没有任何错误。