A digital cultural relic storage and infringement tracing method and system based on a blockchain digital watermark

Abstract

The present application relates to the field of digital copyright protection, and more particularly to a digital cultural relic storage and infringement tracing method and system based on blockchain digital watermarking, which comprises: on the one hand, the digital cultural relic pictures are pretreated first, then the copyright information and user information are constructed and stored on the chain, and finally the watermark pictures are generated and opened to the outside, which ensures the authenticity and credibility of the data and achieves the copyright protection of the digital cultural relics; on the other hand, the suspected infringement pictures are processed reversely, the watermark information is extracted and analyzed from the suspected infringement pictures, and then the authenticity of the watermark information is verified on the blockchain, so that the credible copyright information and leaker (user) information are obtained, which provides credible evidence for subsequent rights protection, and achieves the infringement tracing of digital cultural relics. Based on the method, strong technical support can be provided for the safe use of digital cultural relics, so that the digital cultural relic owners dare to open the digital cultural relic resources to the outside, which helps to realize the true value of the digital cultural relics.

Description

Technical Field

[0001] This invention relates to the field of digital copyright protection, and in particular to a method and system for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking. Background Technology

[0002] In recent years, the digitization of cultural relics has developed rapidly, and China now possesses a large-scale and diverse collection of precious digital cultural relics resources. These digital cultural relics resources contain a wealth of valuable information on history, culture, art, and technology. How to make full use of these digital cultural relics resources to promote the 5,000-year-old and glorious history and civilization of the Chinese nation and enhance my country's cultural soft power is a major issue that urgently needs to be addressed.

[0003] However, in reality, only a small number of digital cultural relics are open to the public, while the vast majority of digital cultural relics are not fully utilized. The main reason for this is the lack of a complete technical support system, which fails to adequately protect the intellectual property rights of digital cultural relics. As a result, owners of digital cultural relics are unwilling or afraid to open up large amounts of digital cultural relics to the public for fear of theft or misuse.

[0004] Digital watermarking is a digital marker that can be a number, serial number, text, image, or other identifier or copyright information. It typically includes the copyright holder's mark or code, as well as basic information such as a user code that verifies the user's legal ownership of the data. Secretly embedding it into digital works can help identify and determine the product's content, copyright, usage rights, and integrity. Traditional digital watermarking technologies are mainly based on filtering methods, such as discrete wavelet transform and discrete cosine transform. Recently, some deep learning-based digital watermarking technologies have emerged.

[0005] Blockchain technology is essentially a distributed ledger technology built on a peer-to-peer network, possessing characteristics such as decentralization, tamper-proofing, and traceability. Blockchain uses digital digests to verify previous transactions, ensuring data integrity and trustworthiness. Based on these characteristics, digital works can be authenticated and their ownership confirmed.

[0006] Traditional digital watermarking-based copyright protection methods establish copyright ownership by embedding the owner's copyright information into digital cultural relics. However, watermark information lacks tamper-proof integrity and credibility, making it impossible to trace responsibility in case of problems. Conversely, storing watermark information on a blockchain, leveraging the immutability and traceability of data on the blockchain, can effectively protect the watermark information and achieve a trustworthy outcome. Currently, the lack of effective solutions in the field of digital cultural relic protection hinders effective protection. Therefore, there is an urgent need for a solution that integrates blockchain and digital watermarking for the storage and infringement tracing of digital cultural relics, enabling copyright protection and infringement tracking, which will facilitate the full utilization of valuable digital cultural relic resources. Summary of the Invention

[0007] To overcome the aforementioned technical problems, this invention provides a method and system for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking. It integrates blockchain and digital watermarking technologies, and combines encrypted hashing and perceptual hashing technologies to realize digital cultural relic copyright preservation and infringement tracing, thereby achieving copyright protection for digital cultural relics and facilitating the trusted sharing and secure utilization of digital cultural relics.

[0008] The specific technical solution is as follows:

[0009] In a first aspect, this invention provides a method for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking, comprising the following steps:

[0010] (1) Data preprocessing: The original digital cultural relic images are subjected to encrypted hash function and perceptual hash function, the copyright information of the digital cultural relic owner is constructed and signed, and the QR code image is used as the carrier of copyright information;

[0011] (2) Watermarked image generation: The QR code image carrying copyright information is embedded into the original digital cultural relic image using the watermark embedding algorithm to generate a digital cultural relic image with watermark;

[0012] (3) Data storage: The original digital cultural relic images are stored in the internal file system, the digital cultural relic images with watermarks are stored in the IPFS file system, the copyright information of the original digital cultural relic images, the owner's signature, the unique hash of the digital cultural relic images, and the unique hash of the watermark images are stored on the blockchain for notarization, and the index information of the digital cultural relic images with watermarks in the IPFS file system, the on-chain transaction ID, the unique hash of the digital cultural relic images, and the unique hash of the watermark images are stored in the MySQL database to complete the notarization of digital cultural relics;

[0013] (4) Extract the unique hash of the QR code image containing copyright information and the watermark image from the suspected infringing image. Based on the unique hash of the watermark image and the unique hash of the digital cultural relic image carried in the QR code image, retrieve the MySQL database to obtain the blockchain transaction ID;

[0014] (5) Based on the transaction ID obtained in step (4), retrieve the real owner's signature on the blockchain and compare it with the owner's signature carried in the QR code image extracted in step (4). If they are inconsistent, it means that the signature / watermark has been destroyed. If they are consistent, use the owner's public key to verify the owner's signature, extract the corresponding copyright information and user information, and complete the infringement tracing.

[0015] Further, step (1) includes:

[0016] (1-1) Image hashing: The original digital cultural relic images are processed using cryptographic hash function and perceptual hash function respectively to obtain the unique hash and similarity hash of the digital cultural relic images, denoted as hash1 and hash2 respectively; if the similarity hash of the digital cultural relic image to be certified exceeds the threshold, the certification is rejected.

[0017] Cryptographic hashing is used to determine the uniqueness of image files, while perceptual hashing is used to determine the similarity between images. When storing digital cultural relic images, a similarity comparison based on hash2 is performed with existing stored images within the system.

[0018] (1-2) Construct copyright information and sign it: The copyright information of digital cultural relics includes system metadata, personal information of the cultural relic owner, and similarity hash2 of the digital cultural relic image generated in step (1-1); use the private key of the digital cultural relic owner to sign the copyright information to obtain the owner's signature;

[0019] Owners of digital cultural relics need to sign the copyright information because only the owner knows the private key, which can provide security protection such as data integrity and non-repudiation.

[0020] Digital signatures are required not only for evidence preservation but also when an owner authorizes others to use digital cultural relics. Digital signatures provide security when authorizing others to use cultural relics, serving as proof of authorization and preventing the authorizer from reneging. In addition to the copyright information mentioned above, user information must also be added when authorizing others to use the relics; this is crucial for subsequent infringement tracking.

[0021] (1-3) Generate QR code image: Use the unique hash of the digital cultural relic image generated in step (1-1) and the owner's signature generated in step (1-2) as input to the QR code generation algorithm to generate a QR code image carrying copyright information.

[0022] Furthermore, before watermarked digital cultural relic images in the IPFS file system are displayed to other users, QR code images need to be regenerated as carriers of copyright and user information, and the watermarked digital cultural relic images are updated before being displayed to users.

[0023] Furthermore, step (2) uses a watermark embedding algorithm to embed a QR code image carrying copyright information into the original digital cultural relic image, thereby generating a watermarked digital cultural relic image. That is, there are two types of digital cultural relic images in the entire system. The original image of the digital cultural relic is stored in an internal file system, inaccessible to external users, thus preventing leakage of the original image. The system only supports the circulation of images with watermark information on the Internet, thereby ensuring the controllability of digital cultural relic copyright and achieving trusted sharing and secure utilization.

[0024] Furthermore, in step (3), data storage includes the storage of the original digital cultural relic images, the storage of digital cultural relic images with watermarks, the storage of evidence information, and the storage of index information;

[0025] The original digital images of cultural relics are stored in the system's internal file system and are prohibited from being accessed by external users;

[0026] The watermarked digital cultural relic images are stored in the distributed file system IPFS. Each image stored on IPFS is indexed by a unique hash address. IPFS is a distributed file system often used to solve the problem of blockchain's difficulty in storing large files. Only by knowing the hash address can the watermarked image be obtained.

[0027] The aforementioned evidence information is stored on the blockchain, including the copyright information of the digital cultural relic image, the owner's signature, the unique hash of the digital cultural relic image, and the unique hash of the watermark image. After being stored on the blockchain, a unique transaction ID is obtained. Based on the characteristics of the blockchain that data is immutable and traceable, storing the copyright information on the blockchain can ensure the authenticity and credibility of the data.

[0028] The index information is stored in a MySQL database, including the unique hash of the digital cultural relic image, the unique hash of the watermarked image, the hash address of the watermarked digital cultural relic image in IPFS, and the transaction ID; storing the above information in the MySQL database facilitates data retrieval for subsequent business operations.

[0029] Furthermore, step (4) includes:

[0030] (4-1) Perform watermark extraction algorithm on suspected infringing images. If extraction fails, it means that the watermark has been destroyed or the suspected infringing image has not infringed, and the infringement tracing ends. If extraction is successful, a QR code image is obtained. Continue to perform QR code extraction algorithm on the QR code image to obtain the unique hash hash1' and the owner's signature S' of the digital cultural relic image.

[0031] (4-2) Use a cryptographic hash function to process suspected infringing images and obtain the unique hash hash3' of the watermarked image;

[0032] (4-3) Search the MySQL database using the unique hash hash1' of the digital cultural relic image and the unique hash hash3' of the watermark image. If the search fails, it means that the suspected infringing image has not infringed and the infringement tracing ends; if the search is successful, the transaction ID is obtained.

[0033] Furthermore, step (5) includes:

[0034] (5-1) Query the transaction in the blockchain according to the transaction ID obtained in step (4) to obtain transaction information, wherein the transaction information is on-chain evidence storage information;

[0035] (5-2) Compare the owner's signature in the on-chain evidence information obtained in step (5-1) with the owner's signature extracted in step (4-1). If the signatures match, proceed to step (5-3). If the signatures do not match, the signature / watermark has been destroyed and the infringement tracing ends.

[0036] (5-3) By verifying the owner's signature using the owner's public key, copyright information and user information, consisting of system metadata, the owner's personal information, and similarity hashes of the digital artifact images, are obtained. Infringement tracing ends. Based on the aforementioned reliable information, legal action can be taken against digital artifact infringers and those who leak information (users). The user information is embedded in the QR code image of the digital artifact image before it is displayed to the user. Specifically, the user information is embedded in the QR code image, the watermark carrier of the watermarked digital artifact image, before it is displayed to the user.

[0037] Secondly, this invention provides a digital cultural relic preservation and infringement tracing system based on blockchain digital watermarking, comprising:

[0038] The login and registration module is used to enable user accounts to log in and register. These user accounts include ordinary users, researcher users, and social organization users.

[0039] The key generation module is used to generate private and public keys for social organization users;

[0040] The work preservation module is used for social institutions to upload their digital cultural relics. The system will provide copyright protection for digital cultural relics based on blockchain and digital watermarking technology, and execute steps (1)-(3) in the above-mentioned digital cultural relics preservation and infringement tracing system.

[0041] The work retrieval module is used for users to retrieve works. Before the system displays the digital cultural relics images with watermarks to users, it is necessary to re-execute steps (1)-(3) in the above-mentioned digital cultural relics preservation and infringement tracing system method to update the digital cultural relics images with watermarks so that the updated digital cultural relics images with watermarks carry user information.

[0042] The artwork download module allows users with download permissions to download digital artifact images with watermarks.

[0043] The infringement tracking module is used to track suspected infringing images and execute steps (4)-(5) in the above-mentioned digital cultural relic preservation and infringement tracing system method.

[0044] Furthermore, the aforementioned digital cultural relic preservation and infringement tracing system also includes:

[0045] The access control module manages user access permissions and digital cultural relic resource permissions. The user access permissions include: ordinary users have viewing permissions, researcher users have viewing and downloading permissions, and social institution users have viewing, downloading, uploading, deleting, and updating permissions. The digital cultural relic resource permissions include public access, access upon request, and private access.

[0046] The backend management module is used to verify the registration information of researchers and social organization users. Only after successful verification can they log in to the system.

[0047] Furthermore, researchers and social organizations must obtain authorization from the digital artifact owner before downloading watermarked images of digital artifacts.

[0048] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0049] This invention integrates blockchain technology and digital watermarking technology. Firstly, the original digital artifact image is hashed, including both cryptographic hashing and perceptual hashing. Cryptographic hashing determines the image's uniqueness, while perceptual hashing determines its similarity. Then, the perceptual hash is compared with existing digital artifact images stored in the system for similarity. If an image with a similarity exceeding a threshold is found, no further processing is performed. Otherwise, copyright information for the image is constructed and embedded into the original digital artifact image using a QR code, generating a watermarked image. Finally, the cryptographic hashes used to determine the original and watermarked images, along with the copyright information, are stored on the blockchain for notarization, thereby achieving copyright verification and confirmation of the digital artifact.

[0050] On the other hand, since the images displayed to users or downloaded by users in the system all carry copyright information and user information, when a suspected infringing image is discovered, it can be traced back to obtain the copyright information and the information of the leaker (user) on the suspected infringing image. Trustworthy authentication can then be performed based on the same transaction data on the blockchain, thus enabling owners to prove their copyright while simultaneously pursuing the infringer's actions and holding the leaker accountable. This is beneficial for digital cultural relic owners to open up their digital cultural relics to the public, allowing precious digital cultural relic resources to be fully utilized. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the architecture of the digital cultural relic preservation and infringement tracing system according to an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram of the workflow of the digital cultural relic preservation and infringement tracing system according to an embodiment of the present invention;

[0053] Figure 3 A schematic diagram of the workflow for digital cultural relic preservation;

[0054] Figure 4 A schematic diagram of the workflow for tracking digital cultural relic infringements. Detailed Implementation

[0055] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not limit it in any way.

[0056] like Figure 1As shown, the digital cultural relic preservation and infringement tracing system of this invention can be divided into four layers according to its hierarchical structure: presentation layer, business logic layer, data access layer, and storage layer. It can also be divided into eight modules according to its modules: login and registration module, key generation module, permission management module, work preservation module, work retrieval module, work download module, infringement tracking module, and backend management module.

[0057] The login and registration module requires users to register before using the system. Registration involves verifying a mobile phone number and email address. Users must also select a user role: general user, researcher, or social organization user (museums, research institutes, etc.). Researchers must upload their professional qualification certificate and wait for verification; social organizations must upload their organization code certificate and wait for verification. Both researchers and social organization users must wait for administrator verification before logging in. Users can authenticate their identity via email password or mobile phone verification code to access system services.

[0058] The key generation module requires the user's RSA public / private key pair when using this system. Users can generate the key locally or through the system's key generation module, and then store the public / private key pair locally.

[0059] The access control module manages user permissions, ensuring that only users with specific privileges can access relevant digital cultural relics resources and perform authorized operations. System permissions are divided into two types: role-based operation permissions and resource usage permissions. Ordinary users have viewing permissions, researchers have viewing and download permissions, and social organizations have viewing, downloading, uploading, deleting, and updating permissions. Digital cultural relics resources can be configured with three access levels: public access, access upon request, and private access.

[0060] The artwork preservation module allows social organizations to upload their own digital cultural relics through this system. The system will provide strong copyright protection for digital cultural relics based on blockchain and digital watermarking technology, encouraging social organizations to open up a large number of precious digital cultural relics resources to the public.

[0061] The artwork search module allows users to retrieve relevant digital cultural relic information through keyword-based search. Search results will be adjusted based on the user's access permissions and the digital cultural relic's usage rights.

[0062] The download module allows users with download permissions to download digital cultural relics. The downloaded digital cultural relics will be embedded with watermark information, which identifies the copyright information of the digital cultural relics and the user information. The watermark information can be used to investigate the infringement of pirates and the liability of users for leakage.

[0063] The infringement tracking module uses watermarks to track infringements, ensuring that both the digital artifact images displayed in the system and those downloaded by users are watermarked. Non-owners of digital artifacts cannot access the original images within the system, but can use the watermark information to track infringements.

[0064] In the backend management module, administrators need to log in to the management system to verify the identities of researchers and social organizations. Only after successful verification can these users log in to the system. In addition, the backend management system can display system statistics, such as the current system status, the number of users in the system, and the number of digital cultural relics.

[0065] In one specific embodiment of the present invention, the workflow of the above system is as follows: Figure 2 As shown, it includes:

[0066] (1) Users need to register in this system first. If you have already registered, you can skip this step. During the registration process, you need to determine your role category and complete the corresponding identity verification. System roles include ordinary users, researcher users, and social organization users. When registering as a researcher or social organization, you need to upload an identity verification certificate. Only after the backend administrator approves the registration will the user be activated.

[0067] (2) Users can authenticate their identity via email password or mobile phone verification code. After successful authentication, they can log in to the system and use system services. For ease of explanation, we will take a social organization user as an example, who has all the operational permissions of the role.

[0068] (3) After entering the system, users can perform operations including work preservation, work retrieval, and infringement tracking;

[0069] (3-1) Evidence of the work

[0070] Social organizations can register their works on this system to authenticate and confirm their rights to their digital cultural relics and declare their copyrights. The system will embed a digital watermark with copyright information into the digital cultural relic images and simultaneously record the copyright information on the blockchain to ensure the authenticity and validity of the information. In this embodiment, the blockchain used is the open-source Hyperledger Fabric consortium blockchain.

[0071] In one specific embodiment of the present invention, the evidence preservation process is as follows: Figure 3 As shown, the process is as follows:

[0072] (3-1a) Users upload images of their digital cultural relics and their private keys, and fill in relevant personal information. User public-private key pairs can be generated through the system's key generation module;

[0073] (3-1b) The system stores digital artifact images in its internal file system;

[0074] (3-1c) The system will perform cryptographic hashing and perceptual hashing on the images uploaded by users to obtain the unique hash and similarity hash of the digital cultural relic images, denoted as hash1 and hash2 respectively. Then, hash2 is used to compare the similarity with the digital cultural relic images already stored in the system. Only when the similarity is lower than the threshold can the subsequent storage process continue.

[0075] (3-1d) The system combines the user's personal information, system metadata, and hash2 to form copyright information; in this embodiment, the system metadata includes the name and version number of the digital cultural relic preservation and infringement tracing system.

[0076] (3-1e) The system uses the user's private key to sign the copyright information and generate the owner's signature S;

[0077] (3-1f) The system takes hash1 and the owner's signature S as input to the QR code generation algorithm and gets the output, obtaining a QR code image;

[0078] (3-1g) The system takes the original digital cultural relic image and the QR code image as input to the watermark embedding algorithm and outputs the watermark image.

[0079] (3-1h) The system stores the watermarked image in IPFS and obtains a unique index, denoted as hash_address;

[0080] (3-1i) The system performs a cryptographic hash algorithm on the watermark image to obtain a unique hash of the watermark image, denoted as hash3;

[0081] (3-1j) The system combines hash1, hash3 and the owner's signature S to construct on-chain information and performs on-chain notarization to obtain the transaction ID, denoted as tx_id;

[0082] (3-1k) The system stores hash1, hash3, hash_address, and tx_id in MySQL as auxiliary index information to facilitate subsequent business queries;

[0083] (3-2) Searching for Works

[0084] (3-2a) Users can enter keywords in the system's search box to retrieve relevant digital cultural relics. The search results will be adjusted based on the user's operation permissions and usage permissions for the digital cultural relics resources. If the digital cultural relic image is being shown to the current user for the first time, then the current user's information needs to be used as user information and adjusted accordingly. Figure 3 The process shown generates corresponding digital artifact images carrying watermark information. To prevent the system from storing too many watermarked images, newly generated watermarked images are set with an expiration time and will be deleted if not used within a certain period.

[0085] (3-2b) If a user has download permissions, they can click to download the digital artifact. The downloaded digital artifact image is watermarked, and the watermark information includes not only the copyright information of the digital artifact but also user information. All digital artifacts in the system are watermarked, and the original images of the digital artifacts are stored in an internal file system that cannot be accessed externally, thereby preventing leakage.

[0086] (3-3) Copyright Infringement Tracking

[0087] When users discover suspected infringing works on the Internet, they can track the infringement through this system. On the one hand, they can prove their copyright and pursue the infringer's infringement; on the other hand, they can find the system users who leaked digital cultural relics and hold them accountable for the leak.

[0088] In one specific embodiment of the present invention, the infringement tracking process is as follows: Figure 4 As shown, the process is as follows:

[0089] (3-3a) Users upload suspected infringing images and their public keys to this system for infringement tracking. User public and private key pairs can be generated through the key generation module of this system;

[0090] (3-3b) The system performs a watermark extraction algorithm on suspected infringing images. If extraction fails, it indicates that the watermark has been damaged or the suspected infringing image is not infringing. If extraction is successful, a QR code image is obtained;

[0091] (3-3c) The system performs a QR code extraction algorithm on the QR code image and obtains the unique hash hash1' and the owner's signature S' of the digital cultural relic image;

[0092] (3-3d) The system performs an encrypted hash algorithm on the suspected infringing image and obtains the unique hash hash3' of the watermarked image;

[0093] (3-3e) The system searches MySQL using the unique hash hash1' of the digital cultural relic image and the unique hash hash3' of the watermark image. If the search fails, it indicates that the suspected infringing image is not infringing, and the system terminates the subsequent process and provides this conclusion. If the search is successful, the tx_id is obtained;

[0094] (3-3f) The system uses tx_id to query transactions in the blockchain and obtain transaction information. This transaction information is the information stored on the blockchain in step (3-2j), including hash1, hash3, and the owner's signature S;

[0095] (3-3g) The system compares the owner's signature S with the owner's signature S' obtained in step (3-3c). If they do not match, it indicates that the signature / watermark has been corrupted, and the system terminates the subsequent process and provides this conclusion. If they match, the following steps can continue.

[0096] (3-3h) The system uses the public key uploaded by the user to verify the owner's signature and obtains system metadata, personal information, hash2, and user information. The user information is added by the system in sub-step (3-2a) of step (3-2) when the user queries digital cultural relic images. The method is similar to steps (3-1c) to (3-1g), except that user information is required in addition to copyright information before the signature algorithm is executed.

[0097] (3-3i) At this point, the user has access to authentic and reliable copyright information as well as information about the user who leaked the digital artifact. The user can then pursue legal action against the infringer for their infringement and the leaker for their liability.

[0098] The embodiments described above provide a detailed explanation of the technical solutions and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, and equivalent substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking, characterized in that, Includes the following steps: (1) Data preprocessing: The original digital cultural relic images are subjected to cryptographic hash function and perceptual hash function, the copyright information of the digital cultural relic owner is constructed and signed, and the QR code image is used as the carrier of copyright information; Step (1) includes: (1-1) Image hashing: The original digital cultural relic images are processed using cryptographic hash function and perceptual hash function respectively to obtain the unique hash and similarity hash of the digital cultural relic images, denoted as hash1 and hash2 respectively; if the similarity hash of the digital cultural relic image to be certified exceeds the threshold, the certification is rejected. (1-2) Construct copyright information and sign it: The copyright information of digital cultural relics includes system metadata, personal information of the cultural relic owner and similarity hash2 of the digital cultural relic image generated in step (1-1); use the private key of the digital cultural relic owner to sign the copyright information to obtain the owner's signature; (1-3) Generate QR code image: Use the unique hash of the digital cultural relic image generated in step (1-1) and the owner's signature generated in step (1-2) as input to the QR code generation algorithm to generate a QR code image carrying copyright information; (2) Watermarked image generation: The QR code image carrying copyright information is embedded into the original digital cultural relic image using the watermark embedding algorithm to generate a digital cultural relic image with watermark; (3) Data storage: The original digital cultural relic images are stored in the internal file system, and the watermarked digital cultural relic images are stored in the IPFS file system. The copyright information, owner signature, unique hash of the digital cultural relic image, and unique hash of the watermarked image of the original digital cultural relic image are stored on the blockchain for notarization. The index information of the watermarked digital cultural relic image in the IPFS file system, the on-chain transaction ID, the unique hash of the digital cultural relic image, and the unique hash of the watermarked image are stored in the MySQL database to complete the notarization of digital cultural relics. Before the watermarked digital cultural relic images in the IPFS file system are displayed to other users, a QR code image needs to be regenerated as a carrier of copyright information and user information. The watermarked digital cultural relic images are updated before being displayed to users. (4) Extract the unique hash of the QR code image containing copyright information and the watermark image from the suspected infringing image. Based on the unique hash of the watermark image and the unique hash of the digital cultural relic image carried in the QR code image, retrieve the MySQL database to obtain the blockchain transaction ID; (5) Based on the transaction ID obtained in step (4), retrieve the real owner's signature on the blockchain and compare it with the owner's signature carried in the QR code image extracted in step (4). If they are inconsistent, it means that the signature / watermark has been destroyed. If they are consistent, use the owner's public key to verify the owner's signature, extract the corresponding copyright information and user information, and complete the infringement tracing.

2. The method for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking according to claim 1, characterized in that, In step (3), data storage includes the storage of the original digital cultural relic images, the storage of digital cultural relic images with watermarks, the storage of evidence information, and the storage of index information; The original digital images of cultural relics are stored in the system's internal file system and are prohibited from being accessed by external users; The watermarked digital cultural relic images are stored in the distributed file system IPFS, and each image stored on IPFS is indexed by a unique hash address; The evidence storage information is stored on the blockchain, including the copyright information of the digital cultural relic image, the owner's signature, the unique hash of the digital cultural relic image and the unique hash of the watermark image. After being stored on the blockchain, a unique transaction ID is obtained. The index information is stored in a MySQL database and includes the unique hash of the digital cultural relic image, the unique hash of the watermarked image, the hash address of the watermarked digital cultural relic image in IPFS, and the transaction ID.

3. The method for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking according to claim 1, characterized in that, Step (4) includes: (4-1) Perform watermark extraction algorithm on suspected infringing images. If extraction fails, it means that the watermark has been destroyed or the suspected infringing image has not infringed, and the infringement tracing ends. If extraction is successful, a QR code image is obtained. Continue to perform QR code extraction algorithm on the QR code image to obtain the unique hash hash1' and the owner's signature S' of the digital cultural relic image. (4-2) Use a cryptographic hash function to process the suspected infringing images to obtain the unique hash hash3' of the watermarked image; (4-3) Search the MySQL database using the unique hash hash1' of the digital cultural relic image and the unique hash hash3' of the watermark image. If the search fails, it means that the suspected infringing image has not infringed and the infringement tracing ends; if the search is successful, the transaction ID is obtained.

4. The method for digital cultural relic preservation and infringement tracing based on blockchain digital watermarking according to claim 3, characterized in that, Step (5) includes: (5-1) Query the transaction in the blockchain according to the transaction ID obtained in step (4) to obtain the transaction information, which is the on-chain evidence information; (5-2) Compare the owner's signature in the on-chain evidence information obtained in step (5-1) with the owner's signature extracted in step (4-1). If the signatures match, proceed to step (5-3). If the signatures do not match, the signature / watermark has been destroyed, and the infringement tracing ends. (5-3) Verify the owner's signature using the owner's public key to obtain copyright information and user information consisting of system metadata, personal information of the cultural relic owner, and similarity hash of the digital cultural relic image, thus ending the infringement tracing process; the user information is embedded in the watermark carrier of the digital cultural relic image—the QR code image—before the watermarked digital cultural relic image is shown to the user.

5. A digital cultural relic preservation and infringement tracing system based on blockchain digital watermarking, used to implement the digital cultural relic preservation and infringement tracing method based on blockchain digital watermarking as described in claim 1, characterized in that the system... include: The login and registration module is used to enable user accounts to log in and register. These user accounts include ordinary users, researcher users, and social organization users. The key generation module is used to generate private and public keys for social organization users; The work preservation module is used for social institutions to upload their digital cultural relics works. The system will provide copyright protection for digital cultural relics works based on blockchain and digital watermarking technology, and execute steps (1)-(3) in the digital cultural relics preservation and infringement tracing system method described in claim 1. The work retrieval module is used for users to retrieve works. Before the system displays the digital cultural relic image with watermark to the user, it is necessary to re-execute steps (1)-(3) in the digital cultural relic evidence storage and infringement tracing system method described in claim 1 to update the digital cultural relic image with watermark so that the updated digital cultural relic image with watermark carries user information. The artwork download module allows users with download permissions to download digital artifact images with watermarks. The infringement tracking module is used to track suspected infringing images and execute steps (4)-(5) in the digital cultural relic preservation and infringement tracing system method described in claim 1.

6. A digital cultural relic preservation and infringement tracing system based on blockchain digital watermarking according to claim 5, characterized in that, Also includes: The access control module manages user access permissions and digital cultural relic resource permissions. The user access permissions include: ordinary users have viewing permissions, researcher users have viewing and downloading permissions, and social institution users have viewing, downloading, uploading, deleting, and updating permissions. The digital cultural relic resource permissions include public access, access upon request, and private access. The backend management module is used to verify the registration information of researchers and social organization users. Only after successful verification can they log in to the system.

7. A digital cultural relic preservation and infringement tracing system based on blockchain digital watermarking according to claim 6, characterized in that, Researchers and social organizations need to obtain authorization from the digital artifact owner before downloading images of digital artifacts with watermarks.

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