A Geographic Image Encryption Method, System, Device and Medium

Abstract

The present invention provides a method, system, device and medium for encrypting geographical images. The method includes: obtaining a geographical image to be processed; setting the initial value of the hyperchaotic Lorenz system to generate a chaotic signal component DX j ; generating a first encryption sequence E M×N , performing a scrambling operation on the geographical image to be processed to obtain a ciphertext image DE M×N ; compressing the scrambled ciphertext image DE M×N into a ciphertext image YE M1×N by combining a differential rule compression algorithm M1×N ; generating a second encryption sequence E M1×N , performing a diffusion operation on the ciphertext image YE M1×N to obtain a ciphertext image KE M1×N ; transmitting the ciphertext image KE M1×N to an execution terminal and performing decryption processing through a decryption key to obtain the original geographical image. The method utilizes the hyperchaotic Lorenz system, scrambling and diffusion operations, and an efficient compression algorithm to achieve secure and fast image encryption and transmission; and incorporates a reversible destruction mechanism to effectively reduce the risk caused by incorrect decryption, and can be applicable to the encryption requirements of various geographical images.

Description

Technical Field

[0001] The present invention relates to the field of image encryption, and more particularly to a geographical image encryption method, system, device and medium. Background Art

[0002] Most of the existing geographical image encryption methods rely on traditional symmetric key algorithms or public key encryption technologies. Although these methods can ensure data security to a certain extent, they are unable to cope with the increasingly complex network security threats. First, the key space of traditional encryption methods is relatively small, making them vulnerable to brute-force attacks. Second, due to the lack of effective scrambling and diffusion mechanisms, once part of the ciphertext is leaked, it may affect the security of the entire image. Third, the separate processing method of compression and encryption in the prior art leads to low efficiency, increasing the transmission time and cost.

[0003] In addition, when an incorrect key is input during the decryption process, the prior art usually cannot provide effective protection measures, which may lead to partial exposure or complete leakage of the original information, posing a serious security risk to users. At the same time, many encryption schemes fail to fully consider the characteristics of geographical images, such as their high resolution and large data volume, making it difficult to balance encryption strength and processing speed in practical applications.

[0004] Therefore, how to design a geographical image encryption method that can be improved in key management, scrambling and diffusion, compression coding, etc., and can effectively protect the security of information when an incorrect key is encountered is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a geographical image encryption method, which performs efficient and secure encryption processing on geographical images through a hyperchaotic Lorenz system combined with a complex encryption algorithm to protect the security of sensitive image data during transmission and storage, and further enhances security through a reversible destruction mechanism in case of decryption failure.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a geographical image encryption method, including the following steps:

[0008] S1. Obtain a to-be-processed geographical image O with a size of M×N M×N ;

[0009] S2. Set the initial value of the hyperchaotic Lorenz system through an encryption key to generate a chaotic signal component DX j ;

[0010] S3. Based on the chaotic signal component DXj Generate the first encryption sequence E M×N , perform scrambling operation on the geographical image O to be processed M×N , and obtain the ciphertext image DE M×N ;

[0011] S4. Compress the scrambled ciphertext image DE M×N into the ciphertext image YE M1×N ;

[0012] S5. Generate the second encryption sequence E j based on the chaotic signal component DX M1×N , perform diffusion operation on the ciphertext image YE M1×N , and obtain the ciphertext image KE M1×N ;

[0013] S6. Transmit the ciphertext image KE M1×N to the execution terminal, and perform decryption processing through the decryption key to obtain the original geographical image.

[0014] Furthermore, the S2 includes:

[0015] S21. Based on the encryption key, set the initial state of the hyperchaotic Lorenz system as (x 0 , y 0 , z 0 , w 0 ); The hyperchaotic Lorenz system is expressed as:

[0016]

[0017] where x, y, z, w are system state variables, is the first-order derivative corresponding to the system state variable, and a, b, c, r are system parameters;

[0018] S22. Perform numerical integration to generate a multi-dimensional floating-point chaotic sequence x(t) with a length of N;

[0019] S23. Convert the chaotic sequence x(t) into an integer chaotic sequence X(t) through the floor rounding function;

[0020] X(t)=floor(x(t)×2 d )

[0021] where d is equal to 16;

[0022] S24. Update the initial state of the hyperchaotic Lorenz system, and repeat the above S22 to S23 to obtain M chaotic signal components DX with a length of N j ; where j = 1, 2, … M.

[0023] Further, the S3 includes:

[0024] S31. Extract the corresponding chaotic signal component DX j Generate the first encryption sequence E M×N ;

[0025] S32. Through the first encryption sequence E M×N , use the non-repetitive scrambling algorithm to generate a non-repetitive scrambling index;

[0026] S33. Expand the geographic image O to be processed M×N into a one-dimensional vector, and perform rearrangement processing according to the non-repetitive scrambling index;

[0027] S34. Convert the rearranged one-dimensional vector into a two-dimensional image to obtain the ciphertext image DE M×N .

[0028] Further, the S4 includes:

[0029] S41. Convert the ciphertext image DE M×N into a one-dimensional vector A;

[0030] S42. Subtract adjacent values of the internal elements in the one-dimensional vector A to obtain the signal B;

[0031] B(i)=A(i - 1)-A(i)

[0032] where the initial B(1)=A(1), i = 2, 3, … n, and n represents the length of the one-dimensional vector A;

[0033] S43. Perform binarization processing on the signal B to obtain the signal C;

[0034]

[0035] where j = 2, 3, … n;

[0036] S44. Convert the signal C into uint8 data from 0 to 255 to generate the signal C';

[0037]

[0038] where m represents the number of groups, m = floor(n / 8)+1; k represents the kth group, and f represents the fth digit in each group;

[0039] S45. Superimpose the signal C' and the absolute value signal B' of the signal B to generate the signal D to be compressed;

[0040] S46. Compress the signal D to be compressed through Huffman coding and convert it into a matrix of M1×N to obtain the ciphertext image YE M1×N .

[0041] Further, the S5 includes:

[0042] S51. Extract the corresponding chaotic signal component DX j Generate the second encryption sequence E M1×N ;

[0043] S52. Perform a forward diffusion operation on the ciphertext image YE M1×N to obtain the ciphertext image FE M1×N ;

[0044]

[0045] S53. Perform a reverse diffusion operation on the ciphertext image FE M1×N to obtain the ciphertext image KE M1×N ;

[0046]

[0047] where C1 and C2 are the forward diffusion coefficient and the reverse diffusion coefficient respectively.

[0048] Further, the S6 includes:

[0049] S61. Judge whether the decryption key is the correct key. If the decryption key is the correct key, obtain the original geographical image; if the decryption key is the wrong key, perform a reversible destruction on the geographical image O to be processed M×N to generate a reversible destruction image P M×N , and perform an encryption process on the reversible destruction image P through the encryption key to obtain the updated ciphertext image KE' M×N ; M1×N ;

[0050] S62. Transmit the updated ciphertext image KE' M1×N to the execution terminal, and extract the marked image through the decryption key; if the marked image is a random image, the decryption fails; otherwise, continue the decryption based on the marked image to obtain the original geographical image.

[0051] Further, in the S61, performing a reversible destruction on the geographical image O to be processed M×N includes:

[0052] S611. Divide the geographical image O to be processed M×N into a*a regions;

[0053] S612. Randomly and non-repeatedly select the region according to the number of incorrect key inputs and perform image flipping to obtain a flipped image;

[0054] S613. Generate a pure white image W M×N with the same size as the geographical image O to be processed M×N , mark the flipped image region as black to generate a marked image SY M×N ;

[0055] S614. Embed the marked image SY M×N into the flipped image to obtain a marked reversible destruction image P M×N ;

[0056] P M×N = bitset(O M×N , bit, SY M×N )

[0057] where bit represents the bit position to be set, and bitset represents the bit position setting function.

[0058] In a second aspect, the present invention provides a geographical image encryption system, including:

[0059] Image input module: used to obtain the geographical image O to be processed with a size of M×N M×N ;

[0060] Chaotic signal generation module: used to set the initial value of the hyperchaotic Lorenz system through an encryption key to generate a chaotic signal component DX j ;

[0061] Scrambling operation module: used to generate a first encryption sequence E j based on the chaotic signal component DX M×N , perform a scrambling operation on the geographical image O to be processed M×N to obtain a ciphertext image DE M×N ;

[0062] Compression coding module: used to compress the scrambled ciphertext image DE M×N into a ciphertext image YE M1×N by combining the differential rule compression algorithm;

[0063] Diffusion operation module: used to generate a second encryption sequence E j based on the chaotic signal component DX M1×N , perform a diffusion operation on the ciphertext image YE M1×N to obtain a ciphertext image KE M1×N ;

[0064] Transmission and decryption module: used to transmit the ciphertext image KE M1×NTransmit it to the execution terminal, perform decryption processing through the decryption key, and obtain the original geographical image.

[0065] In a third aspect, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned geographical image encryption method is implemented.

[0066] In a fourth aspect, the present invention provides a computer-readable storage medium. The storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned geographical image encryption method is implemented.

[0067] The descriptions of the second to fourth aspects in the present invention can refer to the detailed description of the first aspect; and, for the beneficial effects of the descriptions of the second to fourth aspects, reference can be made to the analysis of the beneficial effects of the first aspect, which will not be elaborated here.

[0068] It can be seen from the above technical solutions that compared with the prior art, the present invention has the following beneficial effects:

[0069] 1. The geographical image encryption method provides a highly secure and efficient image encryption scheme by combining the hyperchaotic Lorenz system, scrambling operation, compression algorithm, and diffusion operation. It uses complex chaotic signal components generation and non-repeating scrambling algorithm to ensure that even if part of the ciphertext is intercepted, it will not affect the overall security. By introducing the differential rule compression algorithm and Huffman coding, the data volume is reduced and the transmission efficiency is improved. In addition, the application of forward and reverse diffusion operations enhances the anti-attack ability of the system, ensuring a good avalanche effect, and the modular design allows adjusting parameters according to actual needs to adapt to different application scenarios.

[0070] 2. In the decryption stage, the scheme particularly introduces a reversible destruction mechanism. When encountering an incorrect key, it will not only not disclose the original information, but also perform further encryption processing on the image until the correct key is input, which effectively prevents brute-force cracking. At the same time, the technology maintains good compatibility and scalability, is applicable to geographical images of various sizes, and can provide a reliable framework for encrypting other types of data, thus ensuring information security without affecting the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0072] Figure 1 Flow chart of the geographical image encryption method provided by the embodiment of the present invention;

[0073] Figure 2 For the to-be-processed geographical image O provided by the embodiment of the present invention M×N Schematic diagram of the reversible destruction process;

[0074] Figure 3 Framework diagram of the geographical image encryption system provided by the embodiment of the present invention;

[0075] Figure 4 Schematic diagram of the structure of the electronic device provided by the embodiment of the present invention. Detailed implementation manners

[0076] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0077] The encryption method provided by the embodiments of the present application can be applied to an encryption server. The above encryption server can be hardware or software. When the encryption server is hardware, it can be implemented as a distributed server cluster providing encryption services or as a single server. When the encryption server is software, it can be installed in the above-listed servers. It can be implemented as multiple software or software modules, or as a single software or software module, and no specific limitation is made here.

[0078] Embodiment 1;

[0079] As Figure 1 shown, this embodiment provides a geographical image encryption method, including the following steps:

[0080] S1. Obtain the to-be-processed geographical image O with a size of M×N M×N ;

[0081] S2. Set the initial value of the hyperchaotic Lorenz system through the encryption key to generate the chaotic signal component DX j ;

[0082] S3. Generate the first encryption sequence E j based on the chaotic signal component DX M×N , and perform a scrambling operation on the to-be-processed geographical image O M×N to obtain the ciphertext image DE M×N ;

[0083] S4. Compress the scrambled ciphertext image DE M×N into the ciphertext image YE M1×N ;

[0084] S5. Generate the second encryption sequence E j based on the chaotic signal component DX M1×N , and perform a diffusion operation on the ciphertext image YE M1×N to obtain the ciphertext image KE M1×N ;

[0085] S6. Transmit the ciphertext image KE M1×N to the execution terminal, and perform decryption processing through the decryption key to obtain the original geographical image.

[0086] This geographical image encryption method uses the complex chaotic signal components generated by the hyperchaotic Lorenz system, and confuses and transforms the pixel values of the image through double encryption sequences of scrambling and diffusion. It combines the non-repetitive scrambling algorithm, differential rule compression, and Huffman coding to optimize the data compression efficiency. Its forward and reverse diffusion operations enhance the anti-attack ability; and combined with the decryption error handling mechanism, when the wrong key is input, the original image is reversibly damaged and re-encrypted, which not only prevents unauthorized access, but also ensures the final decryption right of the correct key holder. The overall solution significantly improves the security and confidentiality of geographical images.

[0087] The following further details each step in the above method;

[0088] In this embodiment S1, obtain the geographical image O to be processed with size M×N M×N ;

[0089] Specifically, the geographical image O to be processed here M×N is a color satellite image of a forest area with a resolution of 1269*843 pixels. It is used to analyze the vegetation cover changes in the area for environmental monitoring; these images will be transmitted to the ground station for further processing and analysis. During the transmission process, the security of these sensitive information must be ensured.

[0090] Before starting the encryption, it is also necessary to preprocess the original image to remove cloud occlusion, correct geometric distortion, or standardize the color balance to ensure the optimal image quality and minimize the influence of external factors on the final result.

[0091] In this embodiment S2, set the initial value of the hyperchaotic Lorenz system through the encryption key to generate the chaotic signal component DX j ; Specifically including:

[0092] S21. Based on the encryption key, set the initial state of the hyperchaotic Lorenz system as (x0 , y 0 , z 0 , w 0 ); The hyperchaotic Lorenz system is expressed as:

[0093]

[0094] where x, y, z, and w are system state variables, are the first-order derivatives corresponding to the system state variables, and a, b, c, and r are system parameters; specifically, a = 10, b = 8 / 3, c = 28, and r = -1;

[0095] S22. Perform numerical integration to generate a multi-dimensional floating-point chaotic sequence x(t) of length N;

[0096] S23. Convert the chaotic sequence x(t) into an integer chaotic sequence X(t) through the floor rounding function;

[0097] X(t) = floor(x(t) × 2 d )

[0098] where d is equal to 16;

[0099] S24. Update the initial state of the hyperchaotic Lorenz system, and repeat the above S22 to S23 to obtain M chaotic signal components DX j ; where j = 1, 2,..., M.

[0100] Set the initial state of the hyperchaotic Lorenz system based on the encryption key, and generate a multi-dimensional floating-point chaotic sequence through numerical integration and the rounding function. It not only provides highly random chaotic signal components but also ensures uniqueness under different keys, making the encryption process more random and unpredictable, thereby enhancing the security of encryption.

[0101] In this embodiment S3, based on the chaotic signal component DX j generate the first encryption sequence E M×N , and perform a scrambling operation on the geographic image O to be processed M×N to obtain the ciphertext image DE M×N ; Specifically, it includes:

[0102] S31. Extract the corresponding chaotic signal component DX j to generate the first encryption sequence E M×N ;

[0103] S32. Through the first encryption sequence E M×N , use the non-repeating scrambling algorithm to generate a non-repeating scrambling index;

[0104] S33. Expand the geographic image O to be processed into a one-dimensional vector and rearrange it according to the non-repeating scrambling index; M×N

[0105] S34. Convert the rearranged one-dimensional vector into a two-dimensional image to obtain the ciphertext image DE M×N .

[0106] By extracting chaotic signal components to generate the first encryption sequence and using the non-repeating scrambling algorithm to rearrange the original image, it is ensured that each pixel is only moved once, avoiding the risk of pattern leakage. The image content is effectively confused, making it difficult to restore the original image even with partial information.

[0107] In this embodiment S4, the scrambled ciphertext image DE is compressed into the ciphertext image YE in combination with the differential rule compression algorithm; specifically including: M×N M1×N ;

[0108] S41. Convert the ciphertext image DE into a one-dimensional vector A; M×N

[0109] S42. Subtract adjacent values of the internal elements in the one-dimensional vector A to obtain the signal B;

[0110] B(i) = A(i - 1) - A(i)

[0111] where the initial B(1) = A(1), i = 2, 3,... n, and n represents the length of the one-dimensional vector A;

[0112] S43. Binarize the signal B to obtain the signal C;

[0113]

[0114] where j = 2, 3,... n;

[0115] S44. Convert the signal C into uint8 data from 0 to 255 to generate the signal C';

[0116]

[0117] where m represents the number of groups, m = floor(n / 8) + 1; k represents the k-th group, and f represents the f-th digit in each group;

[0118] S45. Superimpose the signal C' and the absolute value signal B' of the signal B to generate the signal D to be compressed;

[0119] S46. Compress the signal D to be compressed through Huffman coding and convert it into an M1×N matrix to obtain the ciphertext image YE M1×N . ​​​

[0120] In this step, the combined differential rule compression algorithm significantly reduces the data volume of the encrypted image, thereby reducing the costs of transmission and storage, making the encryption process more practical and reliable.

[0121] In this embodiment S5, based on the chaotic signal component DX j generate the second encryption sequence E M1×N , and perform a diffusion operation on the ciphertext image YE M1×N to obtain the ciphertext image KE M1×N ; specifically including:

[0122] S51. Extract the corresponding chaotic signal component DX j to generate the second encryption sequence E M1×N ;

[0123] S52. Perform a forward diffusion operation on the ciphertext image YE M1×N to obtain the ciphertext image FE M1×N ;

[0124]

[0125] S53. Perform a reverse diffusion operation on the ciphertext image FE M1×N to obtain the ciphertext image KE M1×N ;

[0126]

[0127] wherein, C1 and C2 are the forward diffusion coefficient and the reverse diffusion coefficient respectively.

[0128] In the diffusion step, by combining the forward and reverse diffusion operations, the chaos degree of the encrypted image is enhanced. Not only does each pixel in the image become associated with other pixels, but also the dependency relationship between pixel values is increased. Even if part of the data is stolen or tampered with, it is difficult to restore the original image through simple analysis or recombination.

[0129] In this embodiment S6, transmit the ciphertext image KE M1×N to the execution terminal, and perform decryption processing through the decryption key to obtain the original geographical image. Specifically including:

[0130] S61. Judge whether the decryption key is the correct key. If the decryption key is the correct key, obtain the original geographical image; if the decryption key is the wrong key, perform reversible destruction on the geographical image O to be processed M×N to generate the reversible destruction image P M×N , and perform encryption processing on the reversible destruction image P M×N through the encryption key to obtain the updated ciphertext image KE' M1×N ;

[0131] In this step, if the decryption key is the correct key, the original geographical image is obtained, specifically including: after the transmission and decryption module receives the ciphertext image KE M1×N , it verifies whether the input decryption key matches. If the key is correct, the diffusion operation will be performed in reverse using this key to reverse the positive and negative diffusion effects applied before and restore the ciphertext image YE M1×N . Then, through the inverse process of Huffman coding and the reverse calculation of the difference rule, the image is decompressed and reorganized to restore to the scrambled ciphertext image DE M×N . Subsequently, according to the first encryption sequence E M×N , the pixels are rearranged in reverse using the non-repeating scrambling index to cancel the scrambling operation, and finally the original geographical image O M×N is reconstructed.

[0132] Furthermore, if the decryption key is the wrong key, the geographical image O to be processed M×N is reversibly damaged to generate a reversibly damaged image P M×N , and the reversibly damaged image P M×N is encrypted using the encryption key to obtain the updated ciphertext image KE' M1×N ;

[0133] The reversibly damaged image P M×N is encrypted using the encryption key. The process is the same as that in S2 - S5 above and will not be elaborated here;

[0134] S62. Transmit the updated ciphertext image KE' M1×N to the execution terminal, and extract the marked image using the decryption key; if the marked image is a random image, the decryption fails; otherwise, continue decryption based on the marked image to obtain the original geographical image.

[0135] As Figure 2 shown, the reversible damage to the geographical image O to be processed M×N includes:

[0136] S611. Divide the geographical image O to be processed M×N into a * a regions;

[0137] S612. Combine the number of times the wrong key is entered to randomly select the regions without repetition and perform image flipping to obtain a flipped image;

[0138] S613. Generate a pure white image W M×N with the same size as the geographical image O to be processed, mark the flipped regions of the image as black to generate a marked image SY M×N ; M×N ;

[0139] S614. The marked image SYM×N Embedded into the flipped image, we obtain a reversibly damaged image P with a label M×N ;

[0140] P M×N =bitset( M×N , bit, SY M×N )

[0141] Among them, bit represents the bit position to be set, and bitset represents the bit position setting function.

[0142] In formula P M×N =bitset( M×N ,bit,SY M×N ), bitset is a bit position setting function, which sets the position information and the mark image SY according to the bit specified M×N The corresponding position value in the processing geographic image O M×N Set the bit and finally generate a new image P M×N ; If SY M×N The value of the corresponding position in is 0, then P M×N The position specified by the bit in will be set to 0 (off); if the value is non-zero, the corresponding position will be set to 1 (on). This process allows for flexible modification of specific bits in the matrix, thereby achieving precise control and processing of data.

[0143] In this step, the correctness of the decryption key is determined, and the geographic image to be processed is reversibly destroyed and re-encrypted when decryption fails, effectively preventing unauthorized access and data leakage. The reversible destruction mechanism includes steps such as image division, random selection, image flipping, and marker embedding, which ensures the reversibility and controllability of the destruction process. Even in the case of decryption failure, the original image data can be restored by re-entering the correct decryption key. This mechanism not only improves the flexibility of the encryption system, but also provides additional security for users.

[0144] Through the geographic image encryption method described in this embodiment, efficient and secure encryption of geographic images is achieved. The complex chaotic signal components generated by the hyperchaotic Lorenz system are combined with the scrambling and diffusion dual encryption sequences, as well as the difference rule compression algorithm and Huffman coding technology, which significantly improves the security and confidentiality of the encrypted image. At the same time, by introducing the error key processing mechanism and the reversible destruction process, the anti-attack capability and data recoverability of the encryption system are further enhanced.

[0145] Embodiment 2;

[0146] like Figure 3 As shown, this embodiment provides a geographic image encryption system, including:

[0147] Image input module: used to obtain the geographic image O to be processed with dimensions M×N M×N ;

[0148] Chaotic signal generation module: used to set the initial value of the hyperchaotic Lorenz system through an encryption key to generate the chaotic signal component DX j ;

[0149] Scrambling operation module: used to generate the first encryption sequence E based on the chaotic signal component DX j to perform a scrambling operation on the geographic image O to be processed M×N to obtain the ciphertext image DE M×N ; M×N ;

[0150] Compression coding module: used to compress the scrambled ciphertext image DE into the ciphertext image YE by combining the differential rule compression algorithm M×N ; M1×N ;

[0151] Diffusion operation module: used to generate the second encryption sequence E based on the chaotic signal component DX j to perform a diffusion operation on the ciphertext image YE M1×N to obtain the ciphertext image KE M1×N ; M1×N ;

[0152] Transmission and decryption module: used to transmit the ciphertext image KE to the execution terminal and perform decryption processing through the decryption key to obtain the original geographic image M1×N This geographic image encryption system realizes efficient and secure image encryption through the collaborative work of multiple modules. The system uses the chaotic signal generation module to combine the encryption key to generate complex chaotic signals for image scrambling and diffusion, effectively destroying the image structure. The compression coding module reduces the data volume for easy transmission and storage. The overall design not only ensures the security of the geographic image but also improves the efficiency of the encryption process, realizing secure and efficient image encryption and transmission

[0153] Example 3;

[0154] ;

[0155] As shown Figure 4 in this embodiment, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the geographic image encryption method in the above embodiment is realized

[0156] Example 4;

[0157] This embodiment provides a computer-readable storage medium storing a computer program, which when executed by a processor implements the geographic image encryption method in the above embodiment.

[0158] In the above embodiments provided by the present application, it should be understood that the disclosed methods, systems, devices, and media can be implemented in other ways. The method, system, device, and media embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation. Each functional unit can be integrated into a processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0159] Combined with the units and algorithm steps of each example described in the embodiments disclosed in this article, they can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but this implementation should not be considered to exceed the scope of this application.

[0160] Among them, the computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0161] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A geographic image encryption method, characterized in that: The following steps are involved: S1. Obtain the geographic image O to be processed with a size of M×N M×N ; S2, set the initial value of the hyperchaotic Lorenz system through the encryption key to generate the chaotic signal component DX j ; S3, based on chaotic signal component DX j Generate the first encryption sequence E M×N , to be processed geographic image O M×N Perform scrambling operation to obtain the ciphertext image DE M×N ; S4, combined with the difference rule compression algorithm, the scrambled ciphertext image DE M×N Compressed into ciphertext image YE M1×N ; Specifically include: S41, the ciphertext image DE M×N Convert to a one-dimensional vector A; S42, subtract adjacent values ​​of internal elements in the one-dimensional vector A to obtain a signal B; B(i)=A(i-1)-A(i) Wherein, initially B(1)=A(1), i=2,3,…n, n represents the length of the one-dimensional vector A; S43, performing binarization processing on signal B to obtain signal C; Where, j = 2, 3, ... n; S44, converting signal C into uint8 data of 0 to 255 to generate signal C'; Wherein, m represents the number of groups, m=floor(n / 8)+1; k represents the kth group, and f represents the fth digit in each group; S45, superimposing the signal C' with the absolute value signal B' of the signal B to generate a signal D to be compressed; S46, compress the signal D to be compressed by Huffman coding and convert it into a matrix of M1×N to obtain the ciphertext image YE M1×N ; S5, based on chaotic signal component DX j Generate the second encryption sequence E M1×N , for the ciphertext image YE M1×N Perform diffusion operation to obtain the ciphertext image KE M1×N ; S6, the ciphertext image KE M1×N Transmitted to the execution terminal, decrypted using the decryption key to obtain the original geographic image.

2. A geographic image encryption method according to claim 1, characterized in that: The S2 comprises: S21. Based on the encryption key, the initial state of the hyperchaotic Lorenz system is set to (x0, y0, z0, w0); the hyperchaotic Lorenz system is expressed as: Among them, x, y, z, and w are system state variables. is the first-order derivative corresponding to the system state variable, a, b, c, r are system parameters; S22, performing numerical integration to generate a multi-dimensional floating point chaotic sequence x(t) with a length of N; S23, converting the chaotic sequence x(t) into an integer chaotic sequence X(t) by using a floor function; X(t)=floor(x(t)×2 d ) Where d is equal to 16; S24, update the initial state of the hyperchaotic Lorenz system, repeat S22 to S23, and obtain M chaotic signal components DX with a length of N j ; where j=1,2,…M.

3. A geographic image encryption method according to claim 1, characterized in that: The S3 includes: S31, extract the corresponding chaotic signal component DX j Generate the first encryption sequence E M×N ; S32, through the first encryption sequence E M×N , using the non-repetitive scrambling algorithm to generate a non-repetitive scrambling index; S33, the geographic image to be processed O M×N Expand into a one-dimensional vector and rearrange it according to the non-repeating scrambled index; S34, converting the rearranged one-dimensional vector into a two-dimensional image to obtain a ciphertext image DE M×N .

4. A geographic image encryption method according to claim 1, characterized in that: The S5 comprises: S51, extract the corresponding chaotic signal component DX j Generate the second encryption sequence E M1×N ; S52, ciphertext image YE M1×N Perform forward diffusion operation to obtain the ciphertext image FE M1×N ; S53, ciphertext image FE M1×N Perform reverse diffusion operation to obtain the ciphertext image KE M1×N ; Among them, C1 and C2 are the forward diffusion coefficient and the reverse diffusion coefficient respectively.

5. A geographic image encryption method according to claim 1, characterized in that: The S6 comprises: S61, determine whether the decryption key is a correct key, if the decryption key is a correct key, then obtain the original geographic image; if the decryption key is an incorrect key, then treat the geographic image as M×N Perform reversible destruction and generate a reversible destruction image P M×N , and reversibly destroy the image P through the encryption key M×N Perform encryption processing to obtain the updated ciphertext image KE' M1×N ; S62, the updated ciphertext image KE' M1×N It is transmitted to the execution terminal and the marked image is extracted by the decryption key; if the marked image is an irregular image, the decryption fails; otherwise, the decryption continues based on the marked image to obtain the original geographic image.

6. A geographic image encryption method according to claim 5, characterized in that: In the step S61, the geographic image O to be processed M×N Reversible damage, including: S611, the geographic image to be processed O M×N Divide into a*a areas; S612, randomly selecting the area without duplication based on the number of incorrect key inputs and performing image flipping to obtain a flipped image; S613, generate and process geographic image O M×N Pure white image W of the same size M×N , mark the image flip area as black, and generate the marked image SY M×N ; S614: Mark the image SY M×N Embedded into the flipped image, we obtain a reversibly damaged image P with a label M×N ; P M×N =bitset(O M×N ,bit,SY M×N ) Among them, bit represents the bit position to be set, and bitset represents the bit position setting function.

7. A geographic image encryption system, characterized in that: include: Image input module: used to obtain the geographic image O to be processed with a size of M×N M×N ; Chaotic signal generation module: used to set the initial value of the hyperchaotic Lorenz system through the encryption key and generate the chaotic signal component DX j ; Scrambling operation module: used for chaotic signal component DX j Generate the first encryption sequence E M×N , to be processed geographic image O M×N Perform scrambling operation to obtain the ciphertext image DE M×N ; Compression coding module: used to combine the difference rule compression algorithm to decrypt the scrambled ciphertext image M×N Compressed into ciphertext image YE M1×N ; Specifically include: The ciphertext image DE M×N Convert to a one-dimensional vector A; Subtract adjacent values ​​of internal elements in the one-dimensional vector A to obtain signal B; B(i)=A(i-1)-A(i) Wherein, initially B(1)=A(1), i=2,3,…n, n represents the length of the one-dimensional vector A; Binarize signal B to obtain signal C; Where, j = 2, 3, ... n; Convert signal C into uint8 data of 0 to 255 to generate signal C'; Wherein, m represents the number of groups, m=floor(n / 8)+1; k represents the kth group, and f represents the fth digit in each group; Superimpose the signal C' with the absolute value signal B' of the signal B to generate a signal D to be compressed; The signal D to be compressed is compressed by Huffman coding and converted into a matrix of M1×N to obtain the ciphertext image YE M1×N ; Diffusion operation module: used for chaotic signal component DX j Generate the second encryption sequence E M1×N , for the ciphertext image YE M1×N Perform diffusion operation to obtain the ciphertext image KE M1×N ; Transmission and decryption module: used to convert the ciphertext image KE M1×N Transmitted to the execution terminal, decrypted using the decryption key to obtain the original geographic image.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the geographic image encryption method according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the geographic image encryption method according to any one of claims 1 to 6 is implemented.

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