Image encryption method based on chaotic sequence and DNA coding

Abstract

The invention provides an image encryption method based on a chaotic sequence and DNA coding. The method comprises the following steps: calculating a hash value of an image matrix converted from a grayscale image, and updating an initial value of a chaotic system; generating a sequence according to a control parameter of the Bernoulli shift mapping and the updated initial value, wherein the sequence is used as a random value of a Knuth-Durstenfeld shuffling method, and scrambling is carried out on the random value of the Knuth-Durstenfeld shuffling method; carrying out iteration on the Lorenz chaotic system to obtain three sequences; intercepting elements as bits of cyclic shift to perform bit-level scrambling, wherein elements in the sequence are used for selecting codes as a DNA sequence according to a DNA coding rule; performing state conversion by using a Mealy state machine to obtain a new DNA sequence, wherein elements in the sequence are used for DNA coding rule selection for DNA decoding, and a ciphertext image is obtained. According to the method, the randomness of chaos and the nonlinearity of DNA coding and Mealy state conversion are fully utilized, the correlation of adjacent pixels of the image is effectively eliminated, and the security of the ciphertext image is improved.

Description

technical field [0001] The invention relates to the technical field of digital image encryption, in particular to an image encryption method based on chaotic sequence and DNA coding. Background technique [0002] As one of the carriers of network information transmission, image has the characteristics of strong intuition and large amount of information, and plays an important role in Internet communication. It contains a large number of private and confidential images, such as personal medical images, military images, and national defense secrets. The use of digital images in various fields is facing severe security threats. Image encryption is an important means to protect image confidentiality. In order to solve the problem of leaking private content of image information in the process of public channel transmission, there are many mature block encryption schemes at this stage, such as RSA, AES, national encryption algorithm SM4, etc. These encryption schemes have been w...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the technical problems of poor anti-statistical analysis ability of some existing image encryption methods and insufficient security performance of the encryption system, the present invention proposes an image encryption method based on chaotic sequence and DNA encoding, which improves encryption by using the random encoding rules of DNA twice. The complexity of the algorithm makes the image encryption algorithm have higher pseudo-randomness

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