Reversible data hiding in encrypted images using reformed JPEG compression

A scheme of reversible data hiding in encrypted image (RDH-EI) with high embedding capacity is proposed in this paper. First, cover image is transformed to the quantized discrete cosine transform (DCT) coefficients, which are reformed and encrypted to generate the encrypted image. Then the secret message is embedded into the encrypted image in the location of zero alternating current (ac) coefficients to generate the marked encrypted image. The JPEG image can be recovered by using the encryption key. The secret message can be extracted using the embedding key. The experimental results showed that the proposed scheme can obtain a high embedding ratio while ensuring that the recovered image will have good quality.