A novel reversible data hiding in encrypted images based on polynomial arithmetic

Reversible data hiding in encrypted images is an eff ective technique for data hiding and preserving image privacy. In this paper, we propose a novel schema based on polynomial arithmetic, which achieves a high embedding capacity with the perfect recovery of the original image. An effi cient two-layer symmetric en- cryption method is applied to protect the privacy of the original image. One polynomial is generated by the encryption key and a group of the encrypted pixel, and the secret data is mapped into another polynomial. Through the arithmetic of these two polynomials, the purpose of this work is achieved. Fur- thermore, pixel value mapping is designed to reduce the size of auxiliary data, which can further improve embedding capacity. Experimental results demon- strate that our solution has a stable and good performance on various images. Compared with some state-of-the-art methods, the proposed method can get better decrypted image quality with a large embedding capacity.