Reversible Data Hiding in Encrypted Images using Secret Sharing and Frequency Domain Methods

Reversible data hiding in encrypted images (RDHEI) is an evolving field that aims to embed secret data within encrypted images in such a way that the hidden data can be extracted completely while the original image can be recovered perfectly. This technique is essential for applications that require high privacy and security, such as medical imaging, military communication, and cloud storage. This paper proposes a novel scheme for RDHEI that maintains low distortion while improving data hiding capacity and security. This method typically involves three stages: Image encryption, Data embedding, and Data extraction/image recovery. Initially, an image is encrypted using XOR and permutation to ensure its confidentiality. The encryption key undergoes Shamir secret sharing, which divides it into distinct shares, with a certain threshold set that reconstructs the key using the shares during the decryption process. During the data embedding stage, secret information is added to the encrypted image via the Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) based on block classification. Data embedding is done on blocks based on blocktypes obtained through a block classification stage. Finally, during the process of extraction phase, the data that was embedded is extracted from the blocks based on blocktypes and the original image is restored with little distortion. Compared to several cutting-edge methods, the suggested schemes offer superior security and excellent embedding capacity.