Crypt analysis of an image encryption algorithm and an enhanced scheme

This paper analyzes the security issues of the recently proposed JPEG image encryption scheme. A new image encryption algorithm using modified logistic map is proposed. The chaotic sequences generated using modified logistic map are used for permutation, bit swapping and random diffusion. These processes impose the confusion and diffusion effect on the image and make the scheme secure. The security parameters such as entropy, correlation, NPCR and UACI are tested and the results show the scheme is secure.