In early days, information’s are shared in the form of text messages. To secure those messages from unauthorized person AES and DES algorithm are used for hiding the information. Later, the development of technologies peoples starts to sending the information in the form of images. In order to secure the images from hackers and unknown person become a serious challenge in this digital world. AES and DES algorithm are not suited for multimedia information due to some characteristics like high data and high correlation among the pixels.
Those two algorithms are typically designed for the purpose of textual information.1-3 Encryption is a efficient method to solve these issues. Encryption is a process which uses finite set of instruction called an algorithm to convert original image to an encrypted form.A chaotic system is rich in significance and in implication because of ergodicity and pseudorandom sequences.
These structures are too complex and difficult to analyze . one round of permutation and substitution are done to get the accurate result. Here, the permutation and substitution are done by row by row / column by column instead of pixels by pixels in order to increase the speed of encryption4.Wang Xing-Yuan at5 presented a image encryption based on chaotic system and cycle shift. Cycle shift is a suitable for scrambling the images and can also change the values in image pixels. It has large key space, high level security encryption scheme and resistive against known attacks.In6Based on RCA combining chaos , In confusion step,each pixel of image is split into units of bits for permutation.
Logistic map is there for generating the keys and 2D RCA is to achieve the bit level at diffusion stage. It belongs to the symmetric system. Enayatifar at al7 Advanced their work by using tinker bell chaotic map, DNA sequence and CA simultaneously. Here CA is used to generate pseudorandom numbers . For encryption chaotic map is combined with Tinkerbell chaotic mapping.
Wang Leyuan8 proposed a color image encryption based on two complex chaotic system. The main purpose of this paper is to mix RGB channel by using pseudorandom numbers . So, in confusion step pixels are modified by using 2D process and one step process. The mix of RGB channel leads to multilevel encryption.