A Chaotic Image Encryption Algorithm Based on Pixel Scrambling and Bit Substitution

By analyzing the current image encryption algorithm based on a class of chaotic systems, we point that they had security flaws widely.Therefore, we propose a new chaotic image encryption algorithm based on bit substitution and scrambling.The algorithm uses Kent map and Logistic map, and makes the encryption process be related closely with the plaintext image's size and the sum of pixel values. First, A chaotic sequence generated by Kent map is used to make image position global scrambling; Then, use Logistic map to generate two chaotic sequence, and embed scrambling image sequence into the two sequence skillfully.The simulation results show that the algorithm can better resist differential attack, statistical characterization, and can effectively resist chosen plaintext (ciphertext) attacks, and have big key space, good encryption effect.