Digital color image encryption using RC4 stream cipher and chaotic logistic map

Doing a digital image transmission over internet need a secure protection againts ilegall copying. Unfortunately, many current data encryption methods such as DES, RSA, AES, and other only suitable for test data, but not for digital image. In this paper, we propose new secure algorithm for image encryption, which based on RC4 stream cipher algorithm and chaotic logistics map. The proposed algorithm works as follows: (i0 converting the external key into initial value, (ii) using he initial value to generate a key stream using chaotic logistic map function, and (iii) processing a permutation and the result is then XOR-ed with bytes stream of digital image. The experiment results show that the proposed algorithm (i) is able to make the cipher-image can not be visually identified, (ii) can eliminate the statistical correlation between the plain-image and cipher-image, (iii) is very sensitive to small changes of key, and (iv) has no change in image contents (lossless encryption) during encryption and decryption process which is indicated by the hash value (MD5) of plain-image has the same hash value (MD5) wth decrypted image.