Cryptography Based Lossless and Reversible Data Hiding In Encrypted Images

Abstract

For hiding secret data in digital images, large varieties of techniques are available, some are more complex than others. Public key cryptography has various useful applications and the technique employed depends on the requirements of the application to be designed for. Reversible data hiding is a type of data hiding techniques whereby the host image can be recovered exactly. Being lossless makes this technique suitable for medical and military applications. The ciphertext pixels are replaced with the additional data into new values to embed several ciphertext pixels by wet paper coding at multiple layer. From original image the embedded data can be extracted and the original image can be recovered from the decrypted image directly. The embedded data can directly be extracted from the encrypted domain. The decryption of original plaintext image doesn’t affects data embedding operation. With the combined technique, before decryption a receiver may extract a part of embedded data, and recover the original plaintext image after decryption. A slight distortion is introduced due to the compatibility between the lossless and reversible schemes. The data embedding operations can be performed in the two manners simultaneously performed in an encrypted image and decrypted image