Image DNA coding method based on double bases

Abstract

The invention discloses an image DNA coding method based on double bases, and belongs to the field of image encryption. In many fields, a large number of images are generated every day. In order to protect image information from being stolen and improve the security and efficiency of image content network transmission, an image DNA coding method based on double bases is designed. The method comprises the following steps: firstly, defining 256 double-base DNA (Deoxyribose Nucleic Acid) coding rules; secondly, generating a chaos sequence by utilizing Logistic mapping, and performing integer processing; and finally, performing double-base DNA coding on the gray image to generate a corresponding DNA coding matrix. Experimental results show that the new method achieves a good effect in the aspect of security, and is beneficial to improving the security of image content network transmission.

Description

Technical Field

[0001] The present invention relates to the field of image encryption, and in particular to a double-base based image DNA encoding method. Background Art

[0002] In recent years, the security issues of network and information systems have gradually attracted people's attention. Images have the characteristics of being intuitive, vivid, vivid and informative, and have become an important information carrier in people's work and life, and are widely used in communication, military and medical fields. However, due to the openness of the Internet, information is easily intercepted or leaked during network transmission, so it is of great significance to study efficient and secure image encryption methods.

[0003] In 1994, Turing Award winner Adleman solved a 7-node directed Hamiltonian path problem by using the molecular biology tool DNA. This was the first time that the feasibility of computing at the molecular level was experimentally proved, demonstrating the powerful parallel computing capabilities of DNA molecules. DNA computing has significant advantages such as strong information storage capacity, sufficient information processing capacity, high parallelism and extremely low energy consumption, making it play an increasingly important role in the field of image encryption. In recent years, people have proposed a variety of image encryption methods based on DNA computing. DNA computing is based on DNA encoding and decoding. DNA encoding is to convert a decimal pixel value into an 8-bit binary number, and each two binary numbers are represented by one base, so an 8-bit binary can be represented by 4 bases. DNA decoding is the reverse process of encoding, which is to convert each 4 DNA bases into the corresponding decimal number through the decoding rules, that is, to decode the image pixel value. However, the current DNA encoding is based on the principle of encoding each 2-bit binary number into 1 DNA base. There are only 8 DNA encoding rules, and the security is weak. Based on this, in order to expand the number of coding rules, 256 double-base DNA coding rules were designed according to the principle of encoding every 4 binary digits into 2 DNA bases to improve the security of DNA coding. Summary of the invention

[0004] The purpose of the present invention is to propose a double-base based image DNA encoding method to solve the problem that there are few types of DNA encoding rules at present.

[0005] Technical solution of the present invention: In order to achieve the above-mentioned invention object, a double-base-based image DNA encoding method is designed, and the steps are described in detail as follows: Step 1: Define the DNA coding rules for double bases: Each DNA sequence is composed of four bases: adenine (A), guanine (G), cytosine (C) and thymine (T). According to the principle of encoding every 4-bit binary number into 2 DNA bases, the DNA coding rules for double bases are defined as follows: , There are 256 encoding rules in total; among them, the first encoding rule: encode 0000 as AA, encode 0001 as AG, encode 0010 as AC, encode 0011 as AT, encode 0100 as GA, encode 0101 as GG, encode 0110 as GC, encode 0111 as GT, encode 1000 as CA, encode 1001 as CG, encode 1010 as CC, encode 1011 as CT, encode 1100 as TA, encode 1101 as TG, encode 1110 as TC, and encode 1111 as TT; the second encoding rule: encode 0000 as AG, encode 0001 as AA, encode 0010 as AC, encode 0011 as AT, encode 0100 as GA, 0101 as GG, 0110 as GC, and encode 0111 as GT. 111 is encoded as GT, 1000 is encoded as CA, 1001 is encoded as CG, 1010 is encoded as CC, 1011 is encoded as CT, 1100 is encoded as TA, 1101 is encoded as TG, 1110 is encoded as TC, and 1111 is encoded as TT; ...; The 256th encoding rule: 0000 is encoded as AA, 0001 is encoded as AG, 0010 is encoded as AC, 0011 is encoded as AT, 0100 is encoded as GA, 0101 is encoded as GG, 0110 is encoded as GC, 0111 is encoded as GT, 1000 is encoded as CA, 1001 is encoded as CG, 1010 is encoded as CC, 1011 is encoded as CT, 1100 is encoded as TA, 1101 is encoded as TG, 1110 is encoded as TT, and 1111 is encoded as TC; Step 2: Image dimension conversion: Convert an image of size m × n Gray image I Convert to a length of mn Vector P ; Step 3: Generate chaotic sequence: Logistic mapping is: x t+1 = rx t (1- x t ), (1) in, r ∈ [3.57, 4) is the control parameter, x t ∈ (0, 1); randomly select control parameter values r 1 and initial value x 0, iterate using formula (1) mn times, we can get a length of mn Chaotic sequence X ; Step 4: Integerization of chaotic sequence: Using formula (2), X After integer processing, we can get a length of mn Integer chaotic sequence Y , y j = mod [ floor ( x j ×10 15 ), 256]+1, (2) in, j =1, 2, …, mn , x j ∈ X , y j ∈ Y , floor (•) is the floor function, mod (•) is the modulo function; Step 5: Two-base DNA encoding: For any pixel value p j ∈ P ,Will p j Convert to binary number and use the y j Encoding rules for p j Carry out double base DNA coding, j =1, 2, …, mn , we can get a size of mn ×4 DNA base matrix M ; Step 6: Base matrix dimension conversion: M Transformed into a size of m × n ×4 three-dimensional DNA base matrix J , that is I The corresponding DNA encoding matrix.

[0006] Beneficial effects: Aiming at the problem of few types of DNA coding rules, the present invention proposes a double-base based image DNA coding method. The main contributions are: (1) According to the principle of encoding every 4-bit binary number into 2 DNA bases, 256 double-base DNA coding rules are designed, which increases the number of DNA coding rules; (2) The proposed double-base based image DNA coding method is simple to operate and easy to implement, which can significantly improve the security of DNA coding. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 :Flowchart of image DNA encoding based on double bases; Figure 2 : Original image. Implementation

[0008] The implementation process of the present invention is further described in detail below with reference to specific drawings and examples.

[0009] Figure 1 It is a flow chart of the double base-based image DNA encoding method.

[0010] The programming software used is Matlab R2023a, and the Figure 2 The Pepper grayscale image with a size of 512×512 is shown as the experimental object.

[0011] Based on the double base image DNA encoding method, the encoding process steps are detailed as follows: Step 1: Define the DNA encoding rules of the double bases: According to the principle of encoding every 4 binary digits into 2 DNA bases, define the DNA encoding rules of the double bases; Step 2: Image Dimension Conversion: Convert a gray image of size 512×512 I Converted into a vector of length 262144 P ; Step 3: Generate chaotic sequence: randomly select control parameter values r 1=3.8469 and initial value x 0=0.4328, using formula (1) and iterating 262144 times, we can get a chaotic sequence with a length of 262144. X ; Step 4: Integerization of chaotic sequence: Using formula (2), X After integer processing, we can get an integer chaotic sequence with a length of 262144. Y； Step 5: Two-base DNA encoding: For any pixel value p j ∈ P ,Will pj Convert to binary number and use the y j Encoding rules for p j Carry out double base DNA coding, j =1, 2, …, 262144, we get a DNA base matrix of size 262144×4 M ; Step 6: Base matrix dimension conversion: M Transformed into a three-dimensional DNA base matrix of size 512×512×4 J , that is I The corresponding DNA encoding matrix.

Claims

1. A double-base based image DNA encoding method, characterized in that: The encoding process includes the following steps: Step 1: Define the DNA coding rules for double bases: Each DNA sequence is composed of four bases: adenine (A), guanine (G), cytosine (C) and thymine (T). According to the principle of encoding every 4-bit binary number into 2 DNA bases, the DNA coding rules for double bases are defined as follows: ， There are 256 encoding rules in total; among them, the first encoding rule: encode 0000 as AA, encode 0001 as AG, encode 0010 as AC, encode 0011 as AT, encode 0100 as GA, encode 0101 as GG, encode 0110 as GC, encode 0111 as GT, encode 1000 as CA, encode 1001 as CG, encode 1010 as CC, encode 1011 as CT, encode 1100 as TA, encode 1101 as TG, encode 1110 as TC, and encode 1111 as TT; the second encoding rule: encode 0000 as AG, encode 0001 as AA, encode 0010 as AC, encode 0011 as AT, encode 0100 as GA, 0101 as GG, 0110 as GC, and encode 0111 as GT. 111 is encoded as GT, 1000 is encoded as CA, 1001 is encoded as CG, 1010 is encoded as CC, 1011 is encoded as CT, 1100 is encoded as TA, 1101 is encoded as TG, 1110 is encoded as TC, and 1111 is encoded as TT; ...; The 256th encoding rule: 0000 is encoded as AA, 0001 is encoded as AG, 0010 is encoded as AC, 0011 is encoded as AT, 0100 is encoded as GA, 0101 is encoded as GG, 0110 is encoded as GC, 0111 is encoded as GT, 1000 is encoded as CA, 1001 is encoded as CG, 1010 is encoded as CC, 1011 is encoded as CT, 1100 is encoded as TA, 1101 is encoded as TG, 1110 is encoded as TT, and 1111 is encoded as TC; Step 2: Image dimension conversion: Convert an image of size m × n Gray image I Convert to a length of mn Vector P ; Step 3: Generate chaotic sequence: Logistic mapping is: x t+1 = rx t (1- x t )，（1） in, r ∈ [3.57, 4) is the control parameter, x t ∈ (0, 1); randomly select control parameter values r 1 and initial value x 0, iterate using formula (1) mn times, we can get a length of mn Chaotic sequence X ; Step 4: Integerization of chaotic sequence: Using formula (2), X After integer processing, we can get a length of mn Integer chaotic sequence Y , y j = mod [ floor ( x j ×10 15 ), 256]+1，（2） in, j =1, 2, …, mn , x j ∈ X , y j ∈ Y , floor (•) is the floor function, mod (•) is the modulo function; Step 5: Two-base DNA encoding: For any pixel value p j ∈ P ,Will p j Convert to binary number and use the y j Encoding rules for p j Carry out double base DNA coding, j =1, 2, …, mn , we can get a size of mn ×4 DNA base matrix M ; Step 6: Base matrix dimension conversion: M Transformed into a size of m × n ×4 three-dimensional DNA base matrix J , that is I The corresponding DNA encoding matrix.

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