Transformed Logistic Block Cipher Scheme for Image Encryption

Abstract

A transformed logistic block cipher scheme for image encryption is proposed. It includes three major parts, pixel position permutation, block cipher scheme and XORing the resultant values with chaotic key. The key is generated using transformed logistic maps. The proposed chaotic block cipher scheme encrypts blocks of bits rather than blocks of pixels. It encrypts 256-bits of plain image to 256-bits of cipher image with four 32-bit registers. The key space of the proposed method is large enough to protect the system against any brute force, chosen-plaintext/ciphertext, differential and statistical attacks. From the information entropy analysis it is found that, the entropy is very close to the theoretical value which shows that the information leakage is negligible and so the scheme is secure. The simulation results show that the efficient encryption speed is achieved.