Image encryption by blockwise pixel shuffling using Modified Fisher Yates shuffle and pseudorandom permutations

Present paper proposed an image encryption technique using Fisher Yates shuffling along with pseudorandom permutation. Hazra et al [1] proposed a technique that encrypts general file. The technique, however, produced an encrypted file whose size was double than that of the plain text file. The said procedure was not implemented for image encryption as well. In this paper, a modification has been suggested such that the process can be applied for grayscale image encryption and the size of the encrypted image increases marginally. The proposed scheme has been subjected to various forms of analysis like histograms, information entropy, horizontal and vertical correlation coefficients and the results obtained suggests that the modified technique can be used for secure image encryptions.