Ciphertext domain reversible information hiding method and device based on secret image sharing

Abstract

The embodiment of the invention discloses a ciphertext domain reversible information hiding method and device based on secret image sharing. A specific embodiment of the method comprises the following steps: carrying out secret sharing on secret information to be embedded to obtain a secret information sharing copy sequence; carrying out system conversion on the secret information sharing part sequence to obtain a converted information sharing part sequence; performing image scrambling on the secret image by using a preset scrambling key to obtain a scrambled image; performing region division on the scrambled image to obtain an image division region sequence; embedding each converted information sharing copy in the converted information sharing copy sequence into a corresponding image division region in the image division region sequence so as to carry out ciphertext domain reversible information hiding, and obtaining a marked sharing copy sequence; and storing the marked shared copy sequence. According to the embodiment, the calculation complexity of the encryption process can be reduced.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the fields of computer technology and information encryption, specifically to a method and apparatus for reversible information hiding in ciphertext domains based on secret image sharing. Background Technology

[0002] With the rapid development of digital multimedia technology, information security and privacy protection issues have become increasingly prominent. Reversible data hiding (RDH), as an important information security technology, can embed additional information into carrier data (such as images, audio, and video) while ensuring the original carrier data can be recovered without loss. Traditional RDH mainly relies on LSB (Least Significant Bit Replacement) substitution, differential expansion (DE), histogram shift (HS), and prediction error expansion (PEE). The sender embeds authentication information and additional information into the carrier, and the receiver extracts the embedded data in a specific way to recover the carrier image, achieving simultaneous transmission of secret images and secret information.

[0003] However, in today's widely used cloud environment, user-uploaded images are usually encrypted, rendering most traditional RDH methods, which rely on the correlation between pixels in plaintext images, unsuitable. Therefore, the Reversible Information Hiding in Cipherfield (RDHEI, RDH in encrypted image) method has emerged, where a data hider embeds information into an encrypted image. Researchers proposed the first joint RDHI scheme, which embeds one bit of secret information by flipping the three least significant bits (LSBs) of a pixel after encrypting the image using a stream cipher. The receiving end obtains the recovered image and the embedded information based on the spatial correlation of the image. However, this scheme suffers from low embedding rates and certain errors. Subsequently, researchers proposed various improved joint RDHI methods. In joint RDHI methods, data extraction is performed after image decryption. To achieve separability between cover image decryption and data extraction, researchers proposed a series of separable RDHI schemes, such as using a stream cipher [9, 10] and a homomorphic public-key encryption method to encrypt the secret image, thus achieving the separability of the scheme.

[0004] While achieving separability, the aforementioned schemes typically rely on a single image as a carrier, making them susceptible to data loss due to transmission errors or malicious attacks. Furthermore, these schemes suffer from single points of failure, lack of fault tolerance, and difficulty in supporting multi-party collaborative scenarios. To address these issues, researchers proposed the RDHIE scheme, which incorporates secret sharing (SS). This scheme utilizes a (k, n) threshold mechanism to achieve distributed storage of secret images and secret data. Only when a sufficient number of labeled shared copies are collected can the original secret image and embedded data be recovered.

[0005] Next, researchers applied secret image sharing (SIS) to RHEI for the first time. They used a polynomial-based SIS scheme to preserve the correlation between adjacent pixels in the plaintext image to facilitate data embedding. This scheme uses both DE and HS techniques to embed secret data into the image sharing to achieve label sharing. In recent years, researchers have proposed various SIS-based RHEI schemes; however, existing schemes struggle to guarantee high performance across multiple metrics simultaneously. For example, they fail to guarantee simultaneous fault tolerance for data and images, and cannot achieve separability between recovering the secret image and extracting the secret data. They cannot achieve complete recovery of the secret image, still have computational complexity issues, and many schemes suffer from low embedding rates (ER). In addition, most schemes require storing a location map to label the embedding positions; during embedding, the location map needs to be embedded along with the secret data, which reduces the payload to some extent.

[0006] In summary, most existing solutions suffer from the following problems: 1. The storage overhead of the location map reduces the effective payload. 2. Image decryption and data extraction are inseparable. 3. The visual quality of the labeled images needs improvement. 4. The embedding rate needs improvement. 5. Some solutions have high computational complexity due to design limitations. Summary of the Invention

[0007] The summary portion of this disclosure is intended to provide a brief overview of the concepts, which will be described in detail in the detailed description portion. This summary portion is not intended to identify key or essential features of the claimed technical solutions, nor is it intended to limit the scope of the claimed technical solutions.

[0008] Some embodiments of this disclosure provide obstacle information generation methods, apparatuses, electronic devices, and computer-readable media to address the technical problems mentioned in the background section above.

[0009] In a first aspect, some embodiments of this disclosure provide a method for generating obstacle information. The method includes: secretly sharing secret information to be embedded to obtain a sequence of shared secret information portions; performing a binary conversion on the sequence of shared secret information portions to obtain a sequence of converted shared information portions; scrambling a secret image using a preset scrambling key to obtain a scrambled image; dividing the scrambled image into regions to obtain a sequence of image regions, wherein each of the converted shared information portions corresponds one-to-one with a different image region; embedding each of the converted shared information portions in the sequence of converted shared information portions into a corresponding image region in the sequence of image regions to perform reversible ciphertext hiding, obtaining a sequence of marked shared information portions; and storing the sequence of marked shared information portions.

[0010] Secondly, some embodiments of this disclosure provide an obstacle information generation apparatus, which includes: a secret sharing unit configured to secretly share secret information to be embedded, obtaining a secret information sharing sequence; a number system conversion unit configured to perform number system conversion on the secret information sharing sequence, obtaining a converted information sharing sequence; an image scrambling unit configured to scramble a secret image using a preset scrambling key, obtaining a scrambled image; a region division unit configured to divide the scrambled image into regions, obtaining an image division region sequence, wherein the converted information sharing portions correspond one-to-one with the image division regions; an embedding unit configured to embed each converted information sharing portion in the converted information sharing sequence into the corresponding image division region in the image division region sequence to perform reversible information hiding in the ciphertext field, obtaining a marker sharing sequence; and a storage unit configured to store the marker sharing sequence.

[0011] Thirdly, some embodiments of this disclosure provide an electronic device, including: one or more processors; and a storage device having one or more programs stored thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the method described in any implementation of the first aspect above.

[0012] Fourthly, some embodiments of this disclosure provide a computer-readable medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the method described in any of the implementations of the first aspect above.

[0013] The above embodiments of this disclosure have the following beneficial effects: The obstacle information generation method of some embodiments of this disclosure achieves the following technical effects: (1) The storage overhead of the location map leads to a reduction in the effective payload, while this solution does not require the storage of the location map, thus increasing the effective payload. (2) The inseparability of image decryption and data extraction limits the practical application of the solution, while the image decryption and data extraction of this solution can be performed independently. (3) The visual quality of the marked images in some solutions needs to be improved, while the marked images (reconstructed images) of this solution have higher visual quality. (4) The embedding rate is high. (5) Due to design reasons, some solutions have high computational complexity, while this solution avoids complex calculations and saves computational overhead. Attached Figure Description

[0014] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and elements are not necessarily drawn to scale.

[0015] Figure 1 This is a flowchart of some embodiments of the ciphertext domain reversible information hiding method based on secret image sharing according to the present disclosure;

[0016] Figure 2 This is a schematic diagram of the image region division method;

[0017] Figure 3 This is a schematic diagram of the sequence of shared components.

[0018] Figure 4 This is an example diagram of information embedding;

[0019] Figure 5 It is a flowchart of the solution design process;

[0020] Figure 6 Here is an example diagram of peak signal-to-noise ratio;

[0021] Figure 7 This is a schematic diagram of the structure of some embodiments of the ciphertext domain reversible information hiding device based on secret image sharing according to the present disclosure;

[0022] Figure 8 This is a schematic diagram of the structure of an electronic device suitable for implementing some embodiments of the present disclosure. Detailed Implementation

[0023] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0024] It should also be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other.

[0025] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0026] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0027] The names of messages or information exchanged between multiple devices in the embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of such messages or information.

[0028] This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] Figure 1 A flow 100 of some embodiments of the ciphertext domain reversible information hiding method based on secret image sharing according to this disclosure is shown. This ciphertext domain reversible information hiding method based on secret image sharing includes the following steps:

[0030] Step 101: Secretly share the secret information to be embedded to obtain a secret information sharing sequence.

[0031] In some embodiments, the executing entity (e.g., a computing device) of the ciphertext domain reversible information hiding method based on secret image sharing can secretly share the secret information to be embedded via wired or wireless means to obtain a sequence of shared secret information. The secret information may be information that needs to be encrypted.

[0032] It should be noted that the aforementioned wireless connection methods may include, but are not limited to, 3G / 4G / 5G connections, WiFi connections, Bluetooth connections, WiMAX connections, Zigbee connections, UWB (Ultra Wide Band) connections, and other currently known or future wireless connection methods.

[0033] It should be noted that the aforementioned computing devices can be either hardware or software. When the computing device is hardware, it can be implemented as a distributed cluster consisting of multiple servers or terminal devices, or as a single server or a single terminal device. When the computing device is software, it can be installed on the hardware devices listed above. It can be implemented as, for example, multiple software programs or software modules used to provide distributed services, or as a single software program or software module. No specific limitations are made here.

[0034] In some optional implementations of certain embodiments, the execution entity performs secret sharing of the secret information to be embedded, obtaining a sequence of shared secret information, including:

[0035] The following (k-1)th degree polynomial is used to secretly share the secret information to be embedded, resulting in a sequence of shared secret information:

[0036] ,

[0037] in, Represents a prime number, with values ​​of 251 or 257. For the threshold, Indicates the number of participants, coefficient For confidential information, coefficient It is a random number. . A polynomial of degree k-1 is used to represent the sequence of secret information sharing components. Let be the independent variable in the polynomial. In practice, in real-world applications, it can be represented by the participant's label. And calculate the value of the polynomial. A user typically specifies the use of a value. , is used to calculate the value of a polynomial.

[0038] Here, the aforementioned executing entity uses a polynomial (k, n) threshold secret sharing method to secretly share the secret information to be embedded, resulting in a sequence of n secret information sharing copies. Participants are entities that hold and participate in the secret sharing (e.g., servers, IoT devices, encryption systems, etc.).

[0039] Step 102: Convert the number system of the secret information sharing sequence to obtain the converted information sharing sequence.

[0040] In some embodiments, the executing entity can perform a base conversion on the aforementioned secret information sharing sequence to obtain a converted information sharing sequence. Specifically, each current information sharing component in the current information sharing sequence can be converted into a base 2n+1 secret information sharing sequence, where the secret information sharing sequence is a secret number sequence. Here, n represents the number of pixels carrying one secret number in the aforementioned secret number sequence.

[0041] Step 103: Using a preset scrambling key, scramble the secret image to obtain a scrambled image.

[0042] In some embodiments, the execution entity described above can use a preset scrambling key to scramble the secret image, thereby obtaining a scrambled image. Here, the secret image can be any image of a preset size.

[0043] Specifically, image scrambling can be done using a scrambling key. The scrambled image is obtained by rearranging the positions of each pixel in the secret image. .

[0044] Step 104: Divide the scrambled image into regions to obtain a sequence of image regions.

[0045] In some embodiments, the execution entity may divide the scrambled image into regions to obtain an image region sequence. Each converted information sharing portion corresponds one-to-one with a different image region.

[0046] To enhance the security of the secret image, this scheme scrambles it using a scrambling key before processing, resulting in a scrambled image. Then, based on the number of participants n, the scrambled image is divided into n non-overlapping regions, which serve as the image region division sequence.

[0047] In practice, image partitioning methods can include, but are not limited to, at least one of the following: complete block partitioning, vertical block partitioning, horizontal block partitioning, and raster scan sequence block partitioning.

[0048] Specifically, the complete segmentation method divides the scrambled image into n non-overlapping regions. The vertical segmentation method divides the scrambled image vertically into n complete regions. The horizontal segmentation method divides the scrambled image horizontally into n complete regions. The raster scan sequence segmentation method divides the scanned i-th, 2i-th, up to ni-th regions as image regions, resulting in an image region sequence.

[0049] Here, the sequence of image region divisions can be labeled as follows: .

[0050] As an example, see Figure 2The diagram shows the image region division method. Figure 2 The image shows four identical sub-images corresponding to different image segmentation methods. Sub-image (a) corresponds to the image segmented using the complete block method. Sub-image (b) corresponds to the image segmented using the vertical block method. Sub-image (c) corresponds to the image segmented using the horizontal block method. Sub-image (d) corresponds to the image segmented using the raster scan sequence method.

[0051] Step 105: Embed each of the transformed information sharing components in the transformed information sharing component sequence into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, thereby obtaining the labeled sharing component sequence.

[0052] In some embodiments, the execution entity may embed each of the converted information sharing portions in the converted information sharing portion sequence into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, thereby obtaining a marker sharing portion sequence.

[0053] In some optional implementations of certain embodiments, the execution entity embeds each of the transformed information sharing components in the transformed information sharing component sequence into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, resulting in a labeled sharing component sequence, including:

[0054] Step S1: For each image region in the above image region segmentation sequence, perform the following steps:

[0055] The first step is to select k pixels from the image regions described above to form a pixel group.

[0056] The second step is to determine the extraction values ​​corresponding to the aforementioned pixel groups. The extraction values ​​for the aforementioned pixel groups can be determined using the following formula:

[0057] .

[0058] in, This indicates the number of pixels in the aforementioned pixel group; Indicates the serial number. Represents a pixel group. Represents the first pixel in the pixel group Each pixel value.

[0059] Third, in response to determining that the extracted value matches the transformed information sharing portion corresponding to the image segmentation region, the transformed information sharing portion corresponding to the image segmentation region is distributed to the corresponding participant. Matching can be achieved when the extracted value is the same as the secret number in the corresponding transformed information sharing portion.

[0060] Specifically, the transformed information corresponding to the image segmentation regions can be shared using the k-1 degree polynomial described above. This yields... Therefore, it can be... Distribute to the corresponding participants.

[0061] Step S2: In response to the completion of the above image region segmentation sequence processing, a marker-shared sequence is generated.

[0062] Here, the secret information in base 2n+1 can be shared as a sequence. Each secret number in the array is mapped to a pixel group. Each pixel group can contain n pixels. The grayscale value of each pixel in a pixel group is represented as... And define the extraction function f as a weighted sum modulo 2n+1.

[0063] Specifically, if the secret number d in the secret information sharing sequence is the same as the extraction function f value corresponding to the pixel group, then there is no need to modify the number of pixels in the pixel group. Calculate the current number of pixels If the current number of pixels is less than or equal to the original number of pixels n: Then let the s-th pixel group Increment the pixel value by 1; otherwise, let the first pixel value be incremented by 1. Pixel group Subtract 1 from the pixel value in the sequence. This yields the marker-shared sequence. In addition, the extraction function is still calculated for pixel values ​​when extracting secret information.

[0064] As an example, when the threshold values ​​(k, n) in the data embedding step are (3, 4) and (4, 8), the corresponding scrambled image and the shared sequence of the markers are as follows: Figure 3 As shown. Figure 3 Subgraph (a) is the secret image, subgraph (b) is the scrambled image with a threshold value of (3, 4), subgraph (d) is the scrambled image with a threshold value of (4, 8), subgraph (c) is the tag-shared sequence with a threshold value of (3, 4), and subgraph (e) is the tag-shared sequence with a threshold value of (4, 8).

[0065] In practice, information hiding schemes typically use the embedding rate (ER) to objectively reflect the embedding capacity. This scheme employs a polynomial-based secret image sharing method. After sharing, the original secret image becomes a sequence of n labeled shared copies, each smaller than the original image. Therefore, the embedding rate of the scheme needs to be determined from two aspects. The first is the embedding rate of all shared data in the reconstructed image: Embedding rate 1 (ER1) = number of bits of the converted information sharing sequence / number of pixels of the secret image.

[0066] The second is the embedding rate of a single data share in a single tag share: Embedding rate 2 (ER2) = number of bits in a single transformed information share / number of pixels in a tag share.

[0067] Specifically, the embedding rates for different threshold values ​​are shown in Table 1 below.

[0068] Table 1

[0069] k \ n 2 3 4 5 6 7 8 9 2 1.500 / 1.500 1.500 / 1.000 1.500 / 0.750 1.500 / 0.600 1.500 / 0.500 1.500 / 0.429 1.500 / 0.375 1.500 / 0.333 3 - 1.000 / 1.000 1.000 / 0.750 1.000 / 0.600 1.000 / 0.500 1.000 / 0.429 1.000 / 0.375 1.000 / 0.333 4 - - 1.000 / 1.000 1.000 / 0.800 1.000 / 0.667 1.000 / 0.571 1.000 / 0.500 1.000 / 0.444 5 - - - 0.800 / 0.800 0.800 / 0.667 0.800 / 0.571 0.800 / 0.500 0.800 / 0.444 6 - - - - 0.667 / 0.667 0.667 / 0.571 0.667 / 0.500 0.667 / 0.444 7 - - - - - 0.571 / 0.571 0.571 / 0.500 0.571 / 0.444 8 - - - - - - 0.625 / 0.625 0.625 / 0.556 9 - - - - - - - 0.556 / 0.556

[0070] Specifically, the embedding rate is related to the thresholds k and n. As shown in the table above, the overall embedding rate of the scheme is relatively high.

[0071] As an example, such as Figure 4 As shown, taking the threshold value (3, 4) as an example, assume that the six consecutive pixel values ​​are {100, 101, 102, 98, 101, 100}, and the data sharing is d = {5, 1}. When processing, the pixels are divided into two groups. The original polynomial constructed based on the first group of pixels is... .

[0072] Calculate its extraction function The results are consistent with They are not equal, so the calculation continues. At this point, the value of the 2k+1-s-th pixel in the pixel group is reduced by 1, and the polynomial formed by the updated pixel group becomes... Calculate polynomials The value is used to obtain the result. The four resulting pixel values ​​are then distributed to the four participants. The second group of pixels is... The constructed primitive polynomial is The extraction function is The results are consistent with Since they are equal, there is no need to modify the pixel values; the polynomial can be calculated directly. The value is used to obtain the result. The four resulting pixel values ​​are then distributed to the four participants. As can be seen, for each participant, the original six secret image pixels, after being shared and embedded, become two different pixels, thus saving on transmission and storage costs while maintaining security.

[0073] Step 106: Store the marked shared sequence.

[0074] In some embodiments, the executing entity may store the aforementioned tag-shared sequence. Specifically, the tag-shared sequence may be stored in a pre-defined database.

[0075] In practice, the aforementioned execution entity can also consist of multiple modules. For example, such as... Figure 5 As shown, the aforementioned execution entities may include the image owner (module), the data owner (module), and the data hider (module). Therefore, corresponding steps can be implemented through different modules to achieve the hiding of reversible information in the ciphertext field.

[0076] Specifically, the image owner (module) can use a preset scrambling key to scramble the secret image, obtaining a scrambled image. The scrambled image is then divided into regions to obtain a sequence of image regions. The data owner (module) can share data, obtaining n shared data copies (i.e., a sequence of shared secret information copies). These n shared data copies are then converted to different bases to obtain n converted shared data copies (i.e., a sequence of converted shared information copies). Thus, the data hider (module) can share and hide the image regions and converted shared information copies, obtaining n marked shared copies (i.e., a sequence of marked shared copies). This achieves the hiding of reversible information in the ciphertext field.

[0077] in addition, Figure 5 The document also illustrates the decryption steps for reversible information in the ciphertext field. Specifically, it involves extracting information and reconstructing an image from the tokenized shared copy. Information extraction generates a data shared copy, which is then used to recover the ciphertext information. Image reconstruction generates a scrambled image, which, combined with the scrambling key, yields the secret image. This achieves the purpose of information decryption.

[0078] Optionally, the aforementioned implementing entity may also perform the following steps:

[0079] Step S1: In response to receiving a decryption command, information is extracted from at least k token-shared portions of the aforementioned token-shared portion sequence to obtain a data-shared portion sequence. The decryption command can be an information extraction command for the stored token-shared portions.

[0080] Optionally, the aforementioned execution entity extracts information from at least k marked shared portions in the aforementioned marked shared portion sequence to obtain a data shared portion sequence, including:

[0081] The first step is to divide the at least k shared markers into blocks to obtain a block-based shared information sequence. This block division can be performed using the same method as the region partitioning described above.

[0082] The second step is to generate a data sharing sequence based on the above-mentioned block-based shared information sequence.

[0083] Specifically, for each of the aforementioned shared information segments in the segmented shared information sequence, k consecutive pixel values ​​are selected sequentially, denoted as... Then, Lagrange interpolation is used to process each... To obtain the polynomial Next, the extraction function is used to calculate... , , Therefore, the data sharing sequence can be obtained. .

[0084] Step S2: Recover the data from the above-mentioned data sharing sequence to obtain the decrypted secret information.

[0085] Optionally, the aforementioned executing entity performs data recovery on the aforementioned data sharing sequence to obtain decrypted secret information, including:

[0086] The first step is to perform a base conversion on the above-mentioned data sharing sequence to obtain the converted information sequence. Specifically, the above-mentioned data sharing sequence can be converted into a decimal converted information sequence.

[0087] The second step involves interpolating the transformed information sequence to obtain the decrypted secret information. This can be achieved by further interpolating the transformed information sequence using Lagrange interpolation to obtain the decrypted secret information.

[0088] Step S3: Use Lagrange interpolation to perform Lagrange interpolation on the above at least k shared tags. Image interpolation is performed to obtain a reconstructed image, where the participant set , Here, it can be represented as randomly selecting k participants from all n participants for the coding phase. Secondly, the Lagrange interpolation formula... as follows:

[0089] ,

[0090] in, Indicates the serial number. The function value at the interpolation point. This represents the independent variable in a polynomial. Indicates the first The x-coordinates of the interpolation points. Indicates the first The x-coordinates of the interpolation points. Represents a prime number.

[0091] Here, Lagrange interpolation plays a crucial role in threshold-based secret sharing, reconstructing the original secret information using at least k valid shared data through Lagrange interpolation. This ensures that the secret information can only be successfully recovered when a sufficient number (k) of labeled shared copies are collected, demonstrating the security and threshold characteristics of secret sharing.

[0092] Step S4: The reconstructed image is descrambled using the scrambling key to obtain the decrypted image. Specifically, the positions of the scrambled pixels in the reconstructed image can be restored (i.e., descrambled) according to the scrambling key to obtain the decrypted image.

[0093] As an example, during data extraction, the i-th participant extracts data from the i-th region of the labeled shared portion. This region is grouped into k pixels, and an extraction function is calculated to obtain the result, which is the data shared portion d held by that participant. Then, d is converted to decimal format B. After all k participants have extracted their corresponding data shared portions, the secret data can be recovered using Lagrange interpolation. When recovering the image, simply apply Lagrange interpolation to the k labeled shared portions to obtain a scrambled labeled image (the scrambled reconstructed image). Reversing this scrambling using the scrambling key yields the reconstructed image.

[0094] As an example, see Figure 6 The quality of labeled images is evaluated using the peak signal-to-noise ratio (PSNR). When PSNR > 30 dB, it meets the requirements of the human visual system for image observation. A higher PSNR indicates a higher degree of image similarity. Figure 6 As shown, the scheme used a total of 8 test sub-images: test sub-image (a), test sub-image (b), test sub-image (c), test sub-image (d), test sub-image (e), test sub-image (f), test sub-image (g), and test sub-image (h). The PSNR of the reconstructed images were: test sub-image (a): 53.56 dB, test sub-image (b): 49.33 dB, test sub-image (c): 53.64 dB, test sub-image (d): 53.63 dB, test sub-image (e): 53.61 dB, test sub-image (f): 53.62 dB, test sub-image (g): 53.62 dB, and test sub-image (h): 53.62 dB. The test results show that the average PSNR of the reconstructed images is higher than 50 dB, indicating that there is almost no distortion compared to the original images, and the visual quality is extremely high.

[0095] The above-described embodiments of this disclosure have the following beneficial effects: (1) avoiding the additional overhead required for storing location maps, thus improving the payload; (2) achieving the separability of image decryption and data extraction; (3) achieving high visual quality of the labeled images; (4) achieving a high embedding rate; and (5) achieving low computational complexity. This scheme achieves a relatively balanced improvement in all aspects, ensuring superior performance in multiple dimensions.

[0096] Further reference Figure 7As an implementation of the methods shown in the above figures, this disclosure provides some embodiments of a ciphertext domain reversible information hiding device based on secret image sharing. These device embodiments are similar to... Figure 1 Corresponding to the method embodiments shown, this ciphertext domain reversible information hiding device based on secret image sharing can be specifically applied to various electronic devices.

[0097] like Figure 7 As shown, some embodiments of the ciphertext domain reversible information hiding device 700 based on secret image sharing include: secret sharing unit 701, number system conversion unit 702, image scrambling unit 703, region division unit 704, embedding unit 705 and storage unit 706. The system includes: a secret sharing unit 701 configured to secretly share the secret information to be embedded, resulting in a secret information sharing sequence; a number system conversion unit 702 configured to perform number system conversion on the secret information sharing sequence, resulting in a converted information sharing sequence; an image scrambling unit 703 configured to scramble a secret image using a preset scrambling key, resulting in a scrambled image; a region division unit 704 configured to divide the scrambled image into regions, resulting in an image region division sequence, wherein the converted information sharing segments correspond one-to-one with the image region divisions; an embedding unit 705 configured to embed each converted information sharing segment from the converted information sharing sequence into the corresponding image region division in the image region division sequence to perform reversible information hiding in the ciphertext field, resulting in a marked sharing sequence; and a storage unit 706 configured to store the marked sharing sequence.

[0098] It is understandable that the units and references described in the ciphertext domain reversible information hiding device 700 based on secret image sharing are related to... Figure 1 The steps in the described method correspond to each other. Therefore, the operations, features, and beneficial effects described above for the method also apply to the ciphertext domain reversible information hiding device 700 based on secret image sharing and the units contained therein, and will not be repeated here.

[0099] The following is for reference. Figure 8 It illustrates a schematic diagram of the structure of an electronic device (such as a computing device) suitable for implementing some embodiments of the present disclosure. Figure 8 The electronic device shown is merely an example and should not be construed as limiting the functionality or scope of the embodiments of this disclosure. Figure 8As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The memory may include a non-volatile storage medium and internal memory. The non-volatile storage medium may store an operating system and a computer program. The computer program includes program instructions that, when executed, cause the processor to perform any of the methods described above. The processor provides computational and control capabilities to support the operation of the entire computer device. The internal memory provides an environment for the execution of the computer program in the non-volatile storage medium; when executed by the processor, the computer program causes the processor to perform any of the methods described above. The network interface is used for network communication, such as sending assigned tasks. Those skilled in the art will understand that... Figure 8 The structure shown is merely a block diagram of a portion of the structure related to the present disclosure and does not constitute a limitation on the computer device to which the present disclosure is applied. A specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0100] It should be understood that the processor can be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among these, a general-purpose processor can be a microprocessor or any conventional processor.

[0101] In one embodiment, the processor is configured to run a computer program stored in a memory to perform the following steps: secretly sharing the secret information to be embedded to obtain a secret information sharing sequence; performing a base conversion on the secret information sharing sequence to obtain a converted information sharing sequence; using a preset scrambling key to scramble the secret image to obtain a scrambled image; dividing the scrambled image into regions to obtain an image region sequence, wherein the converted information sharing segments correspond one-to-one with the image region; embedding each converted information sharing segment in the converted information sharing sequence into the corresponding image region in the image region sequence to perform reversible information hiding in the ciphertext domain to obtain a marked sharing sequence; and storing the marked sharing sequence.

[0102] This disclosure also provides a computer-readable storage medium storing a computer program, the computer program including program instructions, and the method implemented when the program instructions are executed can be referred to the various embodiments of the methods described above.

[0103] The aforementioned computer-readable storage medium may be an internal storage unit of the computer device described in the foregoing embodiments, such as the hard disk or memory of the computer device. Alternatively, the aforementioned computer-readable storage medium may be an external storage device of the computer device, such as a plug-in hard disk, SmartMedia Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the computer device.

[0104] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0105] The above description is merely a selection of preferred embodiments of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in the embodiments of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of this disclosure.

Claims

1. A method for reversible information hiding in the ciphertext domain based on secret image sharing, characterized in that, include: The embedded secret information is secretly shared to obtain a sequence of shared secret information. The secret information sharing sequence is converted to a different number system to obtain the converted information sharing sequence. Using a preset scrambling key, the secret image is scrambled to obtain a scrambled image; The scrambled image is divided into regions to obtain an image region sequence, wherein the converted information sharing portion corresponds one-to-one with the image region; Each transformed information sharing component in the transformed information sharing component sequence is embedded into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, thereby obtaining the labeled sharing component sequence; The shared sequence of the markers is stored.

2. The method according to claim 1, characterized in that, The process of secretly sharing the secret information to be embedded, resulting in a sequence of shared secret information, includes: The following (k-1)th degree polynomial is used to secretly share the secret information to be embedded, resulting in a sequence of shared secret information: ， in, Represents a prime number, with values ​​of 251 or 257. For the threshold, Indicates the number of participants, coefficient For confidential information, coefficient It is a random number. A polynomial of degree k-1 is used to represent the sequence of secret information sharing components. is the independent variable in the polynomial.

3. The method according to claim 2, characterized in that, The step of dividing the scrambled image into regions to obtain an image region sequence includes: Based on the number of participants The scrambled image is divided into By dividing the image into regions of equal size and without overlap, a sequence of image regions is obtained.

4. The method according to claim 3, characterized in that, The step of embedding each transformed information-sharing portion in the transformed information-sharing portion sequence into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, resulting in a labeled shared portion sequence, includes: For each image region in the image region segmentation sequence, perform the following steps: Select k pixels from the image segmentation region to form a pixel group; Determine the extracted value corresponding to the pixel group; In response to determining that the extracted value matches the transformed information sharing portion corresponding to the image segmentation region, the transformed information sharing portion corresponding to the image segmentation region is distributed to the corresponding participant; In response to the completion of the image region segmentation sequence processing, a marker-shared sequence is generated.

5. The method according to claim 4, characterized in that, The method further includes: In response to receiving a decryption command, information is extracted from at least k token-shared portions in the token-shared portion sequence to obtain a data-shared portion sequence; Data recovery is performed on the shared data sequence to obtain the decrypted secret information; The reconstructed image is obtained by interpolating the at least k labeled shared portions using Lagrange interpolation. The reconstructed image is then reverse-scrambled using the scrambling key to obtain the decrypted image.

6. The method according to claim 5, characterized in that, The step of extracting information from at least k labeled shared portions in the labeled shared portion sequence to obtain a data shared portion sequence includes: The at least k shared markers are divided into blocks to obtain a block-based shared information sequence. Based on the block-based shared information sequence, a data sharing sequence is generated.

7. The method according to claim 6, characterized in that, The step of recovering the data from the shared data sequence to obtain the decrypted secret information includes: The data sharing sequence is converted to a different number system to obtain the converted information sequence. Interpolate the transformed information sequence to obtain the decrypted secret information.

8. A reversible information hiding device for ciphertext domain based on secret image sharing, characterized in that, include: The secret sharing unit is configured to secretly share the secret information to be embedded, thereby obtaining a sequence of secret information sharing copies; The number system conversion unit is configured to perform number system conversion on the secret information sharing sequence to obtain the converted information sharing sequence. The image scrambling unit is configured to scramble the secret image using a preset scrambling key to obtain a scrambled image; The region segmentation unit is configured to segment the scrambled image into regions to obtain an image segmentation region sequence, wherein the converted information sharing portion corresponds one-to-one with the image segmentation region; The embedding unit is configured to embed each of the transformed information sharing components in the transformed information sharing component sequence into the corresponding image segmentation region in the image segmentation region sequence to perform reversible information hiding in the ciphertext domain, thereby obtaining a marker sharing component sequence. The storage unit is configured to store the sequence of tokenized shares.

9. An electronic device, characterized in that, include: One or more processors; Storage device, on which one or more programs are stored, When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-7.

10. A computer-readable medium, characterized in that, It stores a computer program thereon, wherein the program, when executed by a processor, implements the method as described in any one of claims 1-7.

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