New chaotic systems and application in DNA colored image encryption

In recent years, the safe and reliable transmission of image information has received wide attention from scholars. A "one-image, one-secret" image encryption algorithm using chaotic systems and DNA sequences is proposed to address the problems of smaller key space and inability to resist against cropping attacks in encryption algorithms. A new 2-D chaotic system is used to generate a 2-D random matrix equal in size to the color image. The algorithm layers color images into R, G, B three-channel 2-D matrices, blocking the three 2-D matrices after layering and the 2-D random matrix. Chaotic sequences generated by hyperchaotic systems determine how DNA is encoded, decoded, and operated between DNA sub-blocks, which increases the diversity of DNA encoding and operation. Association of images to be encrypted with the 4-D hyperchaotic system, which ensures the "one image, one secret" encryption effect. Simulation results show the effectiveness of the encryption algorithm. Theoretical analysis and simulation experimental result show that the algorithm has large key capacity, strong key sensitivity, and the encrypted image had anti-crop performance, which is important for the research of improving the image encryption effect.