Research On Image Encryption Algorithm Based On Complex Chaotic System

The Internet which is developing rapidly plays an important role in people's life which provides much convenience for people's learning and communication.But the digital image information is widely transmitted in the network as a kind of information carrier because of its vivid and intuitionistic characteristic.However,the network has two-sided nature,bringing convenience to people at the same time,also causing inestimable loss.Therefore,how to ensure the security of the transmission of image information has become a hot issue.This thesis will study the compound chaotic system,use it to generate the sequence for image encryption,so design the following image encryption algorithms to overcome the little control parameters and small range of low-dimensional chaotic system:(1)Design a new one-dimensional compound chaotic system which connected two Logistic maps and a Sine map in parallel to form a new one-dimensional chaotic system with full map,which is applied to the scrambling and diffusion steps of image encryption.(2)Introducing DNA coding into the field of encryption,using the new one-dimensional chaotic system and hyperchaotic system to generate multiple sets of chaotic sequences,a gray-scale image encryption algorithm is designed.(3)The two-dimensional and three-dimensional chaotic systems are combined into a new six-dimensional hyperchaotic system,and a multi-image encryption algorithm is designed based on the bit-plane level theory.The Algorithm designed in this thesis is tested in MATLAB programming environment.Through security analysis,it is proved that the image encryption algorithm designed in this thesis can transmit the image information safely under the condition of satisfying the evaluation standard of image encryption.