an encryption method

Abstract

The invention provides a double chaotic image encryption method based on two-dimensional discrete fractional order Fourier transform. The method is mainly applied to the field of gray scale image encryption. The algorithm comprises the following main content: firstly an auxiliary secret key matrix is generated with the help of plaintext image information to be combined with an input secret key so that the initial secret key of each pixel matrix in the plaintext is obtained; XOR operation is performed on the generated double chaotic matrixes and the plaintext image so that an intermediate ciphertext is obtained; then the generated intermediate ciphertext acts as a two-dimensional discrete fractional order Fourier transform input matrix to perform order Fourier transform and order Fourier transform; and finally Arnold scrambling operation is performed so that the final ciphertext is obtained. The experimental simulation proves that statistical characteristic attack and differential attack can be effectively resisted by the algorithm to greatly hide the plaintext information, and the defect of unsmoothing of the histogram image after the conventional fractional order Fourier transform can be greatly improved so as to achieve the great encryption effect.

Description

technical field [0001] The invention relates to an encryption method, in particular to a double chaotic image encryption method based on two-dimensional discrete fractional Fourier transform. Background technique [0002] In recent years, with the rapid development of the Internet, the security of image information in the process of transmission has received more and more attention. Therefore, how to encrypt images during image transmission has attracted widespread attention from scholars at home and abroad. [0003] Image information is different from ordinary text information, and its own data has strong correlation and redundancy, while traditional data encryption algorithm (DES), public key algorithm (RSA), and elliptic curve algorithm (ECC) are difficult to apply to Image encryption is in progress. In recent years, experts have found that chaotic systems have the characteristics of high sensitivity to initial conditions, positive Lyapunov exponent, fractal and fractal ...

AI Technical Summary

Problems solved by technology

This method solves the shortcomings of insufficient key space, weak dependence between ciphertext and plaintext, and unsmooth gray image histogram, which greatly increases the security of the image.

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