Digital Image Encryption Technology Based on Chaos

Abstract

In the era of Internet and big data, the research of digital image encryption algorithm based on chaos has become one of the research hot spots in the field of information security. Compared with traditional text data, digital images have the characteristics of large amount of data and high redundancy. Traditional methods such as DES, AES and RSA can not meet the requirements of digital image encryption. Because of its initial sensitivity and inherent randomness, chaos is very consistent with the confusion and diffusion concepts of cryptography, so the research on chaotic image encryption has developed rapidly. In this paper, the following research work is mainly focused on chaotic image encryption: Aiming at the dependence of key on plain text image, an image encryption algorithm based on bit plane and improved Logistic map is proposed. The algorithm takes the low 4-Bit bit matrix of the scrambled plain text image as the control parameter of the improved Logistic map, which enhances the dependence of the key on the plain text image, and has a remarkable one-time secret characteristic. According to different bits of image information, encryption algorithms with different strengths are designed to improve the efficiency of the algorithms. Aiming at the diffusion mode of image encryption, an image encryption algorithm based on hyper chaotic system and block modulo is proposed. The algorithm uses hyper chaotic system to alliterative generate chaotic sequences, divides random image blocks around encrypted pixels, and performs integral modulo operation on pixel values in the blocks to obtain encrypted pixel gray values, which effectively expands the diffusion range and enhances the randomness of diffusion.