针对当前可逆信息隐藏技术可分离性差、载体恢复失真较大的问题,提出了一种可分离的加密域可逆信息隐藏方案。在R-LWE公钥密码算法加密过程中,通过对加密域冗余区间的重量化与对密文数据的再编码,可在密文冗余中嵌入十六进制数构成的秘密信息。嵌入信息后,使用隐写密钥可以完整提取隐藏信息,使用解密密钥可以无差错恢复出加密前数据,提取过程与解密过程可分离。理论推导出了影响信息提取与直接解密正确性的相关参数,通过仿真实验得出了参数的可取值区间,实验结果表明本方案在实现加密域的可分离可逆信息隐藏的基础上充分保证了嵌入后的明文解密的可逆性,而且1比特明文在密文域最大可负载4比特秘密信息。
In view of the poor separability and carrier recovery distortion of the current reversible data hiding technology, a novel scheme of separable reversible data hiding was proposed in encrypted domain. Hexadecimal data was embedded by receding in the cipher text redundancy by the weight of the encrypted domain and the receding of the encrypted data in Ring- Learning With Errors (R-LWE) algorithm. With embedded cipher text, the additional data was extracted by using data-hiding key, and the original data was recovered losslessly by using encryption key, and the processes of extraction and decryption were separable. By deducing the error probability of the scheme, the parameters in the scheme which directly related to the scheme's correctness were mainly discussed, and reasonable values of the parameters were got by experiments. The experimental results demonstrate that the proposed scheme can better guarantee the reversibility losslessly and 1 bit plaintext data can maximally load 4 bits additional data in encrypted domain.