Methods for storing artworks on-chain and tracing their provenance

Abstract

The present invention relates to the field of blockchain technology and discloses a method for blockchain-based evidence storage and traceability of artworks. The method comprises the following steps: in the blockchain phase, the seller signs the artwork to be blockchained and broadcasts the signature and the perceived hash value of the artwork to the blockchain; a committee verifies whether the artwork has been blockchained repeatedly. If not, the artwork is officially blockchained and sold on a trading platform designated by the seller; in the artwork transaction phase, the buyer places an order to purchase the artwork; the trading platform publishes the transaction information to the blockchain; the seller ships the artwork; the buyer verifies the received artwork, and if the verification is successful, the transaction is completed; in the artwork traceability phase, the inquirer queries the artwork's historical record through the trading platform or blockchain, including the initial blockchain time and previous transaction information. The present invention solves the problems of title confirmation, traceability, and trust in artwork transactions based on blockchain.

Description

Technical Field

[0001] The present invention relates to the field of blockchain technology, and in particular to a method for storing and tracing artworks on a blockchain. Background Art

[0002] Offline transactions of artworks are usually completed through traditional methods such as galleries, auction houses, and private channels. These transaction processes often include complex identification, evaluation, and negotiation, and the relevant transaction records and artwork circulation information are mostly saved in paper or non-standardized electronic formats. This leads to insufficient transparency in transactions, increases the difficulty of tracing the origin and confirming the ownership of artworks, and makes art transactions face challenges in security and trust.

[0003] With the continuous development of network technology, art trading platforms have gradually improved, providing more convenient, transparent, and efficient channels for the sale of art. While these platforms address some of the issues with traditional trading methods and bring convenience, they still pose risks for copyright protection and traceability. The opacity of trading platforms can conceal fraud and illegal transactions, and user privacy cannot be guaranteed. Furthermore, trading platforms are centralized systems with a single point of failure. Once a core system fails, the entire trading network can be paralyzed. Artwork ownership and traceability are difficult to achieve in centralized systems, making copyright protection difficult.

[0004] In response to this situation, blockchain-based art trading systems have emerged and are developing towards greater security, intelligence, and reliability. However, despite these advances, existing systems still suffer from significant deficiencies in security, privacy protection, and transaction efficiency, which, to a certain extent, hinder the further development of art trading. Therefore, in today's art market, issues of title confirmation, traceability, and trust remain key constraints. Summary of the Invention

[0005] The purpose of this invention is to solve the ownership, traceability and trust issues of artwork transactions based on blockchain, and to provide a method for storing and tracing artworks on the blockchain.

[0006] In order to achieve the above-mentioned object of the invention, the embodiment of the present invention provides the following technical solutions:

[0007] The method for storing artworks on-chain and tracing their provenance includes the following steps:

[0008] Step 1: The artwork is put on the blockchain. The seller signs the artwork to be put on the blockchain and broadcasts the signature and the artwork's perceived hash value to the blockchain. The committee verifies whether the artwork has been put on the blockchain twice. If not, the artwork is officially put on the blockchain and sold on the trading platform designated by the seller.

[0009] Step 2: Artwork transaction phase: The buyer places an order to purchase the artwork; the trading platform publishes the transaction information to the blockchain; the seller verifies whether the transaction information is consistent with the information on the blockchain, and if so, the seller ships the artwork; the buyer verifies the received artwork, and if verification is successful, the transaction is completed;

[0010] Step 3, the artwork traceability stage, the inquirer queries the historical records of the artwork through the trading platform or blockchain, including the initial chain time and previous transaction information.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] This solution combines blockchain technology with art transactions, employing an efficient and resource-friendly delegated proof-of-stake (DPOS) consensus mechanism to significantly reduce computational and storage consumption, making it particularly suitable for resource-constrained environments. Leveraging the immutable nature of blockchain, the system comprehensively records the transaction history and flow of each artwork, ensuring transparency and traceability, and effectively alleviating information asymmetry in the art market. The solution incorporates advanced technologies such as neural networks, perceptual hashing, and the Hamming distance algorithm to generate a unique and unforgeable digital identifier for each artwork. During the transaction process, the solution also incorporates digital signature technology to ensure data non-repudiation and integrity, thereby building a secure and reliable transaction authentication system. Furthermore, the integrated application of smart contracts automates the execution of art transactions, significantly improving transaction efficiency while reducing the risk of human intervention. Leveraging the decentralized nature of blockchain technology, a fair and transparent dispute resolution mechanism is established, further ensuring fair transactions and comprehensive protection of user rights. This solution not only improves the efficiency and security of art transactions but also provides an innovative framework for traceability and copyright protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 Flow chart of the method of the present invention;

[0015] Figure 2 Schematic diagram of a Merkle tree according to an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0017] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures. At the same time, in the description of the present invention, the terms "first", "second", etc. are used only to distinguish the description and are not to be understood as indicating or implying relative importance, or implying any actual relationship or order between these entities or operations. In addition, the terms "connected" and "connected" can refer to direct connection between elements or indirect connection via other elements.

[0018] Example 1:

[0019] This proposal proposes using a public blockchain to document and trace the provenance of artworks. The system architecture consists of a large number of lightweight nodes (i.e., users, including sellers Ua, buyers Ub, and delivery centers E) and several non-lightweight nodes on the blockchain (including trading platforms S, regulatory authorities RA, and testing agencies VI). Multiple regulatory authorities, testing agencies, and trading platforms form a committee. For each transaction, a portion of the committee is voted on to serve as the verification committee and one as the signing committee. These participants form a blockchain network that utilizes the Delegated Proof of Stake (DPOS) consensus mechanism. The core of the DPOS consensus mechanism is that trading platforms, regulatory authorities, and testing agencies are responsible for block generation and network maintenance, while users only have a verification function. As lightweight nodes, users only store block header information and are granted access to blockchain data, primarily for verifying the transfer of artwork ownership. Trading platforms, regulatory authorities, and testing agencies jointly determine who is allowed to upload and modify blockchain information and are responsible for data entry, updating, and maintenance. This permission allocation mechanism ensures data transparency while effectively saving blockchain resources and improving the system's computing efficiency and response speed.

[0020] This solution requires the information {From, TP, T, PHV, To, Sign TP 、SignFrom , EC, Rm} are stored on the blockchain. Among them, the From column is used to store the seller's identity, the TP column is used to store the trading platform's identity, the T column is used to store the time node, the PHV column is used to store the perceived hash value of the artwork, the To column is used to store the buyer's identity, and the Sign column is used to store the buyer's identity. TP One column is used to store the digital signature of the trading platform, Sign From One column is used to store the seller's digital signature, the EC column is used to store the identity of the courier center, and the Rm column is used to store some notes on the transaction information. TP Sign the information in the From, TP, T, PHV, To, and Rm columns. From The information in the columns From, TP, T, PHV, and To is signed. Assume that the public and private key pair of the seller Ua is (Sk Ua , Pk Ua ), the public and private key pair of the buyer Ub is (Sk Ub , Pk Ub ), the public and private key pair of the express center E is (Sk E , Pk E ).

[0021] The present invention is achieved through the following technical solutions: Figure 1 As shown in the figure, the method for storing and tracing artworks on the blockchain includes the following steps:

[0022] Step 1: When the artwork is put on the chain, the seller signs the artwork to be put on the chain and broadcasts the signature and the perceived hash value of the artwork to the blockchain; the committee verifies whether the artwork has been put on the chain twice. If not, the artwork is officially put on the chain and sold on the trading platform designated by the seller.

[0023] Any artwork needs to be put on the blockchain when it is first sold. After being put on the blockchain, the artwork can undergo multiple transactions on the blockchain. It is necessary to ensure that the perceived hash value of the artwork remains unchanged in each transaction, and that the buyer of this transaction is the seller of the next transaction. Step 1 specifically includes the following steps:

[0024] Step 1-1, the seller Ua calculates the perceived hash value PHV of the artwork A A , and sign to get Sign Ua ; The committee determines that artwork A is not a replica and calculates the perceived hash value PHV of artwork A A `.

[0025] Regarding step 1-1, in detail, it includes the following processes:

[0026] (1) Seller Ua uses a terminal device (such as a mobile phone) to take dynamic multi-angle photos of artwork A. RGB fill light is used during the photo shoot, and artwork A is rotated at a constant speed to shoot. This results in a 10-15 second video with multi-angle and fill light changes. Multiple frames of images with different angles and lighting are extracted from the video. The angle changes of the mobile phone gyroscope are used to extract multiple frames of images. For example, one frame is extracted every 30 degrees, and 6-12 frames of images covering 360 degrees can be extracted. The following data must also be collected synchronously during the photo shoot: the trajectory of the mobile phone gyroscope (i.e., the rotation angle and speed during the photo shoot), the depth information of the ToF sensor (i.e., the distance to the object surface), and the reflection sequence (i.e., the reflective characteristics of the artwork surface under the mobile phone fill light). The multiple frames of images are detected using the Laplacian variance and the blurred frames are discarded.

[0027] (2) The seller Ua inputs multiple frames of images into the MobileNet model to obtain feature vectors, and calculates the perceptual hash value PHV of the artwork A based on the feature vectors A The MobileNet network is deployed in the blockchain network, and users can use it directly through the port without deploying the model. The seller Ua uses his own private key Sk Ua Sign the information b={From, TP, T, PHV, To}. The specific content of information b is b={ID Ua 、ID S 、Seller's application time for on-chain T1、PHV A , null value}, where ID Ua Indicates the identity of the seller Ua, ID S Indicates the identity of the trading platform S, PHV A Represents the perceived hash value of artwork A. Seller Ua uses private key Sk Ua After signing the information b, the digital signature Sign of the seller Ua is obtained Ua =Sign(Sk Ua , ID Ua ||ID S ||T1||PHV A || null value).

[0028] (3) The seller Ua sends the committee multiple frames of images, the trajectory of the phone's gyroscope, the depth information of the ToF sensor, and the reflection sequence. The committee uses LSTM to analyze the reflection changes between the multiple frames of images and detect the naturalness of the material of the artwork to determine whether it is a forgery, which can greatly resist the attack of 3D imitations. For example, if the reflection changes suddenly, the artwork is judged to be a counterfeit, because the reflection of oil paint is usually gradual, while the reflection of printed materials is sudden. Another example is that the trajectory of the phone's gyroscope does not match the change in the perspective of the multiple frames of images, such as when the phone is stationary but the picture is moving, the artwork is judged to be a counterfeit.

[0029] (4) After the committee determines that artwork A is not a replica, it inputs multiple frames of images into the MobileNet model to obtain feature vectors, and calculates the perceptual hash value PHV of artwork A based on the feature vectors. A `.

[0030] In step 1-2, the seller Ua broadcasts the on-chain information c to the blockchain, indicating the intention to sell the artwork A on the trading platform S.

[0031] Uplink information c={From, TP, T, PHV, To, Sign TP 、Sign From , EC, Rm}, the specific content of the chain information c is c={ID Ua 、ID S , T1, PHV A , null value, null value, Sign(Sk Ua , ID Ua ||ID S ||T1||PHV A ||null), null, null}.

[0032] Step 1-3: After receiving the on-chain information c, the committee uses the public key Pk of the seller Ua Ua Decrypt and view the PHV in the chain information c A Whether and Sign Ua PHV A Consistent with PHV A `Similarly, the ID in the chain information c Ua Whether and Sign Ua If the comparison is successful, proceed to the next step.

[0033] The similarity comparison is as follows. The committee sets the threshold t of the Hamming distance and the PHV in the chain information c. A With PHV A Compare the Hamming distance bit by bit to determine whether the Hamming distance is less than the threshold t. If it is less than t, there is similarity and proceed to the next step (the threshold t here is the same as the threshold t in steps 1-4).

[0034] In steps 1-4, the verification committee verifies whether artwork A is duplicated on the chain.

[0035] The blockchain numbers the committee and uses random numbers to select some as the verification committee. The verification committee will use the perceived hash value PHV in the chain information c A Compare with the existing perceived hash value on the blockchain. The specific process is as follows:

[0036] (1) The verification committee compares PHVs one by one AEach existing perception hash value PHV on the blockchain i The Hamming distance Hd i , assuming that there are n perceived hash values ​​of artworks on the blockchain, then there is PHV i ∈{PHV1,PHV2,...,PHV n The Hamming distance represents the number of different characters at corresponding positions between two strings of equal length and is used to measure the similarity between perceptual hash values.

[0037]

[0038] Where m is the length of the perceived hash value; j is the number of bits of the perceived hash value length; PHV A (j) is PHV A Perceptual hash value at the jth digit; PHV i (j) is PHV i Perceptual hash value on j digits.

[0039] (2) The verification committee sets the threshold t of the Hamming distance to determine whether the artwork A has been put on the chain. , it means that artwork A has not been put on the chain, and the chain information c is put into the transaction pool; otherwise, it means that artwork A has been put on the chain, and there may be plagiarism issues with the artwork, and the artwork is rejected from being put on the chain.

[0040] Steps 1-5: After the committee reaches a consensus, artwork A is officially uploaded to the blockchain.

[0041] The non-validating committee obtains the on-chain information c from the transaction pool and ensures that its content complies with the blockchain protocol requirements, such as correct formatting and a valid timestamp. A Byzantine fault-tolerant vote is then conducted, and consensus is reached if more than two-thirds of the non-validating committee members vote. The validating committee removes the consensus on the on-chain information c from the transaction pool and integrates it into a new block. The validating committee broadcasts the generated new block to the entire blockchain network, and artwork A is officially on-chain.

[0042] Steps 1-6: Trading platform S publicly displays and sells artwork A.

[0043] After artwork A is uploaded to the blockchain, trading platform S verifies whether the TP in the uploaded information c is its own identity ID. S If yes, the trading platform S and the seller Ua negotiate and confirm the price, then select a front image from multiple frames of images, and send the front image of artwork A and the perceived hash value PHV A The price is uploaded to the server for public display and sale on the trading platform S.

[0044] Step 2: Artwork transaction phase. The buyer places an order to purchase the artwork. The trading platform publishes the transaction information to the blockchain. The seller verifies whether the transaction information is consistent with the information on the blockchain. If they are consistent, the seller ships the artwork. The buyer verifies the received artwork. If the verification is successful, the transaction is completed.

[0045] After an artwork is uploaded to the blockchain, transactions primarily take place on the trading platform S, with the blockchain primarily serving as a distributed ledger. Buyers and sellers act as lightweight nodes, and for each transaction, they must locally store information such as the hash of the block containing artwork A (previous block hash), the block's Merkle root, the block's generation timestamp (T1), and the verification committee's signature.

[0046] Taking a transaction of artwork A between seller Ua and buyer Ub as an example, step 2 specifically includes the following steps:

[0047] In step 2-1, the buyer Ub requests the trading platform S to check whether the on-chain information c of artwork A is authentic, and pays if it is authentic.

[0048] Buyer Ub intends to purchase artwork A on trading platform S and requests to view the blockchain information c of artwork A. Trading platform S retrieves the blockchain information c={ID Ua 、ID S , T1, PHV A , null value, null value, Sign(Sk Ua , ID Ua ||ID S ||T1||PHV A ||null value), null value, null value} and transaction number r1 are sent to the buyer Ub.

[0049] After receiving the on-chain information c, the buyer Ub performs hash processing to obtain a hash value H. The received on-chain information c is verified by the hash value H. If the verification is successful, the buyer Ub places an order for artwork A on the trading platform S and completes the payment. The verification process is as follows:

[0050] (1) The buyer Ub performs hash processing on the acquired chain information c to obtain H{ID Ua 、ID S , T1, PHV A , null value, null value, Sign(Sk Ua , ID Ua ||ID S ||T1||PHV A||null value), null value, null value}, initiates a query request to the verification committee and sends transaction number r1. The query request contains a Merkle path query for artwork A.

[0051] (2) After receiving the query request, the verification committee finds the block containing artwork A from the blockchain based on transaction number r1 and returns the Merkle1 path of artwork A to the buyer Ub as a response.

[0052] (3) The buyer Ub calculates the hash values ​​in the Merkle1 path layer by layer based on the hash value H, and finally obtains the Merkle1 root. The calculated Merkle1 root is compared with the locally stored Merkle root. If they are the same, it proves that the chain information c of the artwork A is stored in the blockchain and is correct, indicating that the verification is successful.

[0053] As an example, Figure 2 As shown, assuming that the buyer Ub intends to query the artwork A, after obtaining the information of the artwork A, hash processing is performed to obtain the hash value N0, and N0 is sent to the verification committee to initiate a query request. The verification committee sends the hash value of the found Merkle path {N0→N4→N5} and the node {N0, N1, N4, N5} to the buyer Ub based on N0; the buyer Ub calculates the hash value layer by layer, first calculates N4 through N0 and N1, and then calculates the Root through N4 and N5; the calculated Root (that is, the Merkle1 root) is compared with the locally stored Merkle root. If they are the same, the verification is successful.

[0054] In step 2-2, the trading platform S publishes the transaction information d to the blockchain and notifies the seller Ua to ship the goods.

[0055] The transaction platform S publishes the transaction information d to the blockchain to transfer the ownership of the artwork A. The transaction information is d={From, TP, T, PHV, To, Sign TP 、Sign From , EC, Rm}, the specific content of transaction information d is d={ID Ua 、ID S , the time when the buyer pays T2, PHV A 、ID Ub 、Sk S , ID Ua ||ID S ||T2||PHV A ||ID Ub )、Sk Ua , ID Ua ||ID S ||T1||PHVA ||ID Ub ), null value, null value}, where Sk S Indicates the private key of the trading platform S, Sign S =Sign(Sk S , ID Ua ||ID S ||T2||PHV A ||ID Ub ). The committee uses the public key Pk of the trading platform S S Sign S Decode the ID obtained by decoding S If the ID in the transaction information d S If they are consistent, the committee successfully verifies the identity of the trading platform S, and the transaction information d is officially uploaded to the blockchain. The trading platform S notifies the seller Ua to ship the goods and sends the transaction number r2 to the seller Ua, and provides the buyer Ub with the delivery address.

[0056] In step 2-3, the seller Ua verifies whether the ownership of artwork A has been changed through the transaction information d on the blockchain. If the change is successful, the artwork A is shipped.

[0057] The verification process is as follows:

[0058] (1) The seller Ua sends a query request to the committee and sends the transaction number r2 of artwork A to the committee; the committee queries the transaction information d of artwork A and the Merkle2 path of artwork A through transaction number r2, and the committee returns the transaction information d and Merkle2 path to the seller Ua as a response.

[0059] (2) The seller Ua calculates the Merkle2 root layer by layer through the Merkle2 path, and compares the calculated Merkle2 root with the locally stored Merkle root. If they are the same, it means that the ownership of the artwork A has been successfully transferred and it is shipped.

[0060] (3) The seller Ua takes the artwork A to the courier center E. The courier center E extracts the features of the artwork A to obtain the feature vector (same as step 1-1), and calculates the perceptual hash value of the feature vector to obtain PHV A ``, PHV A ``Sent to the committee. The committee based on PHV A ``Search for similar PHVs on the blockchain A If there is a similar one, the transaction information d and Merkle2 path of artwork A will be sent to the express center E.

[0061] (4) The courier center E checks the transaction information d and the Merkle2 path and calculates the Merkle2 root layer by layer. It compares the calculated Merkle2 root with the locally stored Merkle root. If they are the same, the artwork A is packaged and shipped.

[0062] In step 2-4, the express delivery center E applies to upload the shipping information e to the chain, and the seller Ua informs the trading platform S of the express delivery number.

[0063] The express center E will send the shipping information e={From, TP, T, PHV, To, Sign TP 、Sign From , EC, Rm} and digital signature of the express center E Send to the committee to apply for chain, the specific content of the delivery information e is e={ID Ua 、ID S , T2, PHV A 、ID Ub 、Sk S , ID Ua ||ID S ||T2||PHV A ||ID Ub )、Sk Ua , ID Ua ||ID S ||T1||PHV A ||ID Ub ||null value), ID E , null value}, where ID E It is the identity mark of the express center E. E =(Sk E , ID E ) is the digital signature of the courier center E, Sk E It is the private key of the express center E.

[0064] After receiving the delivery information e, the committee uses the public key Pk of the express center E E Sign E Decode to get ID E , the ID obtained by comparing the decryption E and the ID in the shipping information E Are they consistent? If they are consistent, the committee agrees to upload the shipping information e to the chain. After uploading the information to the chain, the committee will send the transaction number r3 to the seller.

[0065] The seller Ua sends the transaction number r3 to the committee. The committee sends the shipping information e and the Merkle path to the seller Ua. The seller Ua verifies whether the value of EC is ID by comparing the hash value of the shipping information e and the locally stored Merkle root. E If so, the seller pays the postage and obtains the courier number. If artwork A is lost or counterfeit, the fault lies with courier center E. Seller Ua informs trading platform S of the courier number, which verifies the tracking number to confirm whether seller Ua has shipped the item.

[0066] Step 2-5, the buyer Ub verifies the perceived hash value PHV of the received artwork A A *, if the verification is successful, the transaction of artwork A is completed.

[0067] The buyer Ub signs for artwork A in person and extracts features from artwork A to obtain a feature vector. Based on the feature vector, the perceived hash value PHV is calculated. A *, compared with PHV A * The same as PHV in the upper chain information c A Are they similar? (The similarity comparison method is the same as steps 1-3). If they are similar, it means that artwork A has not been tampered with or forged, and the transaction of artwork A is completed.

[0068] In step 2-6, if the verification fails, the buyer Ub clicks "Reject" on the trading platform S. The trading platform S restores the transaction information f and puts it on the blockchain. The transaction is now complete.

[0069] If they are not similar, the buyer Ub clicks "Reject" on the trading platform S, and the trading platform S will send the transaction information f={ID Ua 、ID S , T2, PHV A , null value, Sign S 、Sign Ua 、ID E , us} to restore, where us indicates that the transaction was unsuccessful, To restores to the state when the buyer Ub did not purchase, Sign S =Sign(Sk S , ID Ua ||ID S ||T2||PHV A ||null value||us), To restores to the state when the buyer Ub did not purchase, broadcasts the transaction information f to the committee, and the committee verifies Sign S Are the IDs inside consistent with the IDs in the transaction information f? If they are consistent, the transaction information f will be uploaded to the chain. After uploading to the chain, the committee will send the transaction number r4 to the seller.

[0070] In summary, the three parties to a transaction (seller Ua, trading platform S, and buyer Ub) will sign a smart contract that details the rights and obligations of each party, ensuring transparency, fairness, and automated execution of the transaction. Specifically, seller Ua is required to pay a deposit to trading platform S as a guarantee of contract fulfillment. If seller Ua fails to ship the artwork within the agreed timeframe, the smart contract automatically triggers a deduction mechanism, deducting a corresponding penalty from the deposit. This ensures a smooth transaction and protects the rights of all parties. If buyer Ub pays trading platform S but discovers that S has delayed updating the blockchain information, S will be penalized accordingly. If the courier EC loses the artwork during delivery, EC assumes full responsibility.

[0071] Step 3, the artwork traceability stage, the inquirer queries the historical records of the artwork through the trading platform or blockchain, including the initial chain time and previous transaction information.

[0072] The artwork traceability process is realized through the blockchain network. The queryer L inputs the perceived hash value PHV of the artwork A. A (In this case, the queryer L is someone who has participated in the transaction of artwork A) or the identity ID of the seller Ua Ua (At this time, the inquirer L is a person who has not participated in the transaction of artwork A) Query the complete circulation history of artwork A, the blockchain verifies the transaction continuity and information integrity, and finally presents key information in a visual way.

[0073] The step 3 specifically includes the following steps:

[0074] Step 3-1: The queryer L enters the perceived hash value PHV of artwork A through the trading platform S or blockchain browser. A Or the seller Ua's identity ID Ua , as the keyword for tracing. The trading platform S or the blockchain node retrieves all historical records related to the artwork A based on the input keyword. These historical records include: initial on-chain information {ID Ua , Application time for on-chain T1, Perception hash value PHV A}、Trading information {ID Ub , multiple transaction times T2, Rm}.

[0075] In step 3-2, the blockchain sorts the retrieved records in chronological order and verifies the continuity and authenticity of the transactions by comparing the perceived hash value of each transaction with the seller's identity. The verification process is as follows:

[0076] (1) Verify whether the buyer Ub of the kth transaction and the seller Ua of the k+1th transaction are the same person.

[0077]

[0078] If the transaction is unsuccessful, a record will appear , , the Rm column is us.

[0079] (2) Ensure the perceived hash value PHV of artwork A A It remains unchanged in each transaction to verify the uniqueness of artwork A.

[0080]

[0081] Step 3-3, use the signature of the verification committee to verify the authenticity and immutability of each record, and use the public key Pk of the trading platform S S Decrypt the signature to ensure that all information about artwork A has not been tampered with since it was uploaded to the blockchain. The decryption process is as follows:

[0082] (1) Extract the signature of the verification committee and the corresponding digest of each record from the blockchain.

[0083] (2) Use the public key Pk of the trading platform S S Decrypt the digital signature to obtain the message digest Digest, and verify whether the message digest Digest is consistent with the Digest in the record. If they are consistent, it means that the record has not been tampered with.

[0084] Step 3-4: Finally, the traceability results are presented to the inquirer L in a visual manner. The traceability results include: the initial seller, the buyers and sellers of all previous transactions, and the time of all previous transactions.

[0085] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. The method for storing artworks on-chain and tracing their provenance is characterized by: The following steps are involved: Step 1: The artwork is put on the blockchain. The seller signs the artwork to be put on the blockchain and broadcasts the signature and the artwork's perceived hash value to the blockchain. The committee verifies whether the artwork has been put on the blockchain twice. If not, the artwork is officially put on the blockchain and sold on the trading platform designated by the seller. The step 1 specifically includes the following steps: Step 1-1, the seller Ua calculates the perceived hash value PHV of the artwork A A , and sign to get Sign Ua ; The committee determines that artwork A is not a replica and calculates the perceived hash value PHV of artwork A A `; Step 1-2: Seller Ua broadcasts the on-chain information c to the blockchain, indicating his intention to sell artwork A on trading platform S. Step 1-3: After receiving the on-chain information c, the committee uses the public key Pk of the seller Ua Ua Decrypt and view the PHV in the chain information c A Whether and Sign Ua PHV A Consistent with PHV A `Similarly, the ID in the chain information c Ua Whether and Sign Ua If the comparison is successful, proceed to the next step; Steps 1-4: The Verification Committee verifies whether artwork A is duplicated on the chain; Steps 1-5: After the committee reaches a consensus, artwork A is officially uploaded to the blockchain. Steps 1-6: Trading platform S publicly displays and sells artwork A; Step 2: Artwork transaction phase: The buyer places an order to purchase the artwork; the trading platform publishes the transaction information to the blockchain; the seller verifies whether the transaction information is consistent with the information on the blockchain, and if so, the seller ships the artwork; the buyer verifies the received artwork, and if verification is successful, the transaction is completed; Step 3, the artwork traceability stage, the inquirer queries the historical records of the artwork through the trading platform or blockchain, including the initial chain time and previous transaction information.

2. The method for storing artworks on-chain and tracing their provenance according to claim 1, characterized in that: In step 1-1, the seller Ua calculates the perceived hash value PHV of the artwork A. A , and sign to get Sign Ua The steps include: The seller Ua uses his own private key Sk Ua For information b={ID Ua 、ID S , T1, PHV A , To} to sign and obtain the digital signature Sign of the seller Ua Ua =Sign(Sk Ua , ID Ua ||ID S ||T1||PHV A ||To), where ID Ua The ID of the seller Ua S is the identity of the trading platform S, T1 is the time when the seller applies for listing on the chain, PHV A is the perceived hash value of artwork A, and To is the identity identifier of the buyer; in information b, To is an empty value.

3. The method for storing artworks on-chain and tracing their provenance according to claim 2, characterized in that: In the steps 1-2, the uplink information c is c={ID Ua 、ID S , T1, PHV A 、To、Sign S 、Sign Ua ,EC,Rm}, where Sign S is the digital signature of the transaction platform S, EC is the identity of the express center, and Rm is the remarks; in the chain information c, To, Sign S , EC, and Rm are all null values.

4. The method for storing artworks on-chain and tracing their provenance according to claim 3 is characterized in that: The step 2 specifically includes the following steps: Step 2-1: Buyer Ub requests the trading platform S to check whether the blockchain information c of artwork A is authentic. If so, payment is made. Step 2-2: The trading platform S publishes the transaction information d to the blockchain and notifies the seller Ua to ship the goods. Step 2-3: Seller Ua verifies whether the ownership of artwork A has been changed through transaction information d on the blockchain. If the change is successful, artwork A is shipped. Step 2-4: Courier center E applies to upload the shipping information e to the blockchain, and seller Ua informs the courier number to trading platform S; Step 2-5, the buyer Ub verifies the perceived hash value PHV of the received artwork A A *, if the verification is successful, the transaction of artwork A is completed; In step 2-6, if the verification fails, the buyer Ub clicks "Reject" on the trading platform S. The trading platform S restores the transaction information f and puts it on the blockchain. The transaction is now complete.

5. The method for storing artworks on-chain and tracing their provenance according to claim 4 is characterized in that: The step 2-1 is specifically as follows: After the artwork is on-chain, in each transaction, the information that users need to store locally includes: the hash value of the block where the artwork A is located, the Merkle root, the timestamp T1` of the block generation, and the signature of the verification committee; Buyer Ub intends to purchase artwork A on trading platform S and requests to view the blockchain information c of artwork A. Trading platform S retrieves the blockchain information c and transaction number r1 from the blockchain and sends them to buyer Ub. After receiving the on-chain information c, the buyer Ub performs hash processing to obtain a hash value H. The received on-chain information c is verified by the hash value H. If the verification is successful, the buyer Ub places an order for artwork A on the trading platform S and completes the payment. The verification process is as follows: (1) The buyer Ub performs hash processing on the acquired chain information c to obtain H{ID Ua 、ID S , T1, PHV A 、To、Sign S 、Sign Ua , EC, Rm}, initiates a query request to the verification committee and sends the transaction number r1. The query request contains the Merkle path query for artwork A; (2) After receiving the query request, the verification committee finds the block containing artwork A from the blockchain based on transaction number r1 and returns the Merkle1 path of artwork A to the buyer Ub as a response; (3) The purchaser Ub calculates the hash values ​​in the Merkle1 path layer by layer based on the hash value H, and finally obtains the Merkle1 root; the calculated Merkle1 root is compared with the locally stored Merkle root. If they are the same, it proves that the chain information c of the artwork A is stored in the blockchain and is correct, indicating that the verification is successful.

6. The method for storing artworks on-chain and tracing their provenance according to claim 4 is characterized in that: In step 2-2, the transaction information d is d={ID Ua 、ID S , T2, PHV A 、ID Ub 、Sign S 、Sign Ua , EC, Rm}, where T2 is the time when the buyer Ub pays, Sign S =Sign(Sk S , ID Ua ||ID S ||T2||PHV A ||ID Ub ||Rm), EC and Rm are empty in the transaction information d; after being put on the chain, the trading platform S sends the transaction number r2 to the seller Ua and informs the seller Ua to ship the goods.

7. The method for storing artworks on-chain and tracing their provenance according to claim 6, characterized in that: The steps 2-3 are specifically as follows: (1) Seller Ua sends a query request to the committee and sends the transaction number r2 of artwork A to the committee. The committee uses the transaction number r2 to query the transaction information d of artwork A and the Merkle2 path of artwork A. The committee returns the transaction information d and the Merkle2 path to seller Ua as a response. (2) The seller Ua calculates the Merkle2 root layer by layer through the Merkle2 path, and compares the calculated Merkle2 root with the locally stored Merkle root. If they are the same, it means that the ownership of the artwork A is successfully transferred and the artwork is shipped; (3) The seller Ua takes the artwork A to the courier center E. The courier center E extracts the features of the artwork A to obtain the feature vector, and then calculates the perceptual hash value of the feature vector to obtain PHV A ``, PHV A ``Sent to the committee; the committee based on PHV A ``Search for similar PHVs on the blockchain A If yes, then send the transaction information d and Merkle2 path of artwork A to the courier center E; (4) The courier center E checks the transaction information d and the Merkle2 path and calculates the Merkle2 root layer by layer. It compares the calculated Merkle2 root with the locally stored Merkle root. If they are the same, the artwork A is packaged and shipped.

8. The method for storing artworks on-chain and tracing their provenance according to claim 6, characterized in that: In the steps 2-4, the shipping information e is e={ID Ua 、ID S , T2, PHV A 、ID Ub 、Sign S 、Sign Ua 、ID E , Rm}, where ID E It is the identity of the express center E, and Rm is a null value.

9. The method for storing artworks on-chain and tracing their provenance according to claim 8, characterized in that: The steps 2-5 are as follows: the buyer Ub signs for the artwork A in person, extracts features from the artwork A to obtain a feature vector, and calculates the perceptual hash value PHV based on the feature vector. A *, compared with PHV A * The same as PHV in the upper chain information c A Is it similar? If so, it means that Artwork A has not been tampered with or forged, and the transaction of Artwork A is completed. The steps 2-6 are as follows: the buyer Ub clicks "Reject" on the trading platform S, and the trading platform S sends the transaction information f={ID Ua 、ID S , T2, PHV A , null value, Sign S 、Sign Ua 、ID E , us} to restore and upload to the chain, where us indicates that the transaction was unsuccessful, To is restored to the state when the buyer Ub did not purchase, Sign S =Sign(Sk S , ID Ua ||ID S ||T2||PHV A ||NULL||us).

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