Reversible data hiding in encrypted images (RDHEI) is a widely used technique for privacy protection, which has been developed in many applications that require high confidentiality, authentication and integrity. Proposed RDHEI methods do not allow high embedding rate while ensuring losslessly recover the original image. Moreover, embedding computational complexity and embedding rate are not satisfactory when using public key encryption-based methods. This paper proposes a new fully reversible method based on Paillier homomorphic cryptosystem and pixel prediction. We use gradient adjust prediction to obtain redundant space in the original image and embed secret information with homomorphic operation after encryption. Experimental results show that our scheme can achieve high capacity (near 0.95 bpp) and can losslessly recover the original images with peak signal to noise ratio of +∞ and structural similarity of 1. Compared with proposed reversible data hiding algorithms, our scheme has a significant improvement in reconstructing quality, safety and capacity.

中文翻译：

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基于同态加密和像素预测的加密图像完全可逆数据隐藏方案

加密图像中的可逆数据隐藏（RDHEI）是一种广泛使用的隐私保护技术，已在许多需要高机密性、身份验证和完整性的应用中得到发展。提出的 RDHEI 方法在确保无损恢复原始图像的同时不允许高嵌入率。此外，当使用基于公钥加密的方法时，嵌入计算复杂度和嵌入率并不令人满意。本文提出了一种基于Paillier同态密码系统和像素预测的新的完全可逆方法。我们使用梯度调整预测在原始图像中获得冗余空间，并在加密后通过同态操作嵌入秘密信息。实验结果表明，我们的方案可以实现高容量（接近 0.