Self-Adaptive Chaotic Logistic Map: An Efficient Image Encryption Method

Digital image encryption algorithm is different from text encryption because of some inherent features of image such as huge data capacity and high correlation among the neighboring pixels. Correlation about image is neglected by most encryption algorithm. According to the Shannon's theory, the higher the correlation of the image, the lower the information entropy. This paper proposed improved chaotic map named self-adaptive logistic chaotic map. Encryption intensity of proposed algorithm alerts with information entropy of image by using the properties of the chaotic maps such as sensitivity to the initial conditions and random-like behave. Lyapunov exponent of the logistic map can change with the correlation index and information entropy of the image. That means the lower the correlation index of the image, the higher the Lyapunov exponent, the higher the encryption intensity.