Separable Reversible Data Hiding In Encrypted Image

Abstract

The field steganography is a very popular technique for sending secret messages and a lot of researches are going on it. The project on separable reversible data hiding in encrypted image uses Rijndael algorithm which is an iterated block cipher algorithm that uses encryption or decryption of a block of data that is accomplished by the iteration of a specific transformation. As input, Rijndael accepts 1-D 8-bit byte arrays that create data blocks. The plaintext is input and then mapped onto state bytes. The design of Rijndael is based on easily understandable mathematical concepts including finite field mathematics and linear algebra and matrix manipulation. Using an encryption key, the person which has information to send encrypts the original image. With an encrypted image containing data, if a receiver has the data-hiding key, he can extract the data without knowing the content of the image. The receiver cannot extract the data by just having an encryption key, but by having this key, he can decrypt to obtain an image similar to the original one. If the receiver has both the data-hiding key and the encryption key, he can extract the additional data to recover the original content without any error by exploiting the spatial correlation in natural image when the amount of additional data is not too large
Keywords— Rijndael, AES, encryption, decryption,spatial correlation, steganography