A new chaos based color image encryption algorithm using permutation substitution and Boolean operation

A new color image encryption algorithm is proposed by using chaotic maps. Cipher image is constructed in three phases. In the first phase permutation of digital image is performed with the help of a chaotic map. The second phase uses chaotic substitution box for pixel substitution and finally in the third phase a Boolean operator XOR is used for mixing chaotic logistic based random sequence. Chaotic maps have main role in this encryption. Chaos theory, due to its randomness and unpredictable behaviors, is known as favorite for the purpose of image encryption. The RGB components of image scrambled by permutation-substitution and Boolean operation, show good results for security and performance analysis. Different tests of security analysis like key space, key sensitivity, correlation analysis, entropy, histogram analysis, number of pixel change rate (NPCR) and unified average changing intensity (UACI) tests are employed on the proposed scheme. On the basis of these tests, we believe that proposed scheme is well suited for practical applications.