Artwork chaining evidence storage and tracing method

Abstract

The invention relates to the technical field of block chains, and discloses an artwork chaining evidence storage and source tracing method, which comprises the following steps: an artwork chaining stage: a seller signs an artwork needing to be chained, and broadcasts a signature and a perceptual hash value of the artwork to a block chain; the committee verifies whether the artwork is repeatedly linked, if not, the artwork is formally linked, and the artwork is sold on a transaction platform specified by a seller; in the artwork transaction stage, the purchaser places an order to purchase artworks; the transaction platform issues the transaction information to the block chain; the seller delivers goods; the purchaser verifies the received artwork, and if verification succeeds, the transaction is completed; in the artwork traceability stage, an inquirer inquires historical records of artworks through a transaction platform or a block chain, and the historical records comprise initial chaining time and previous transaction information. According to the invention, right confirmation, source tracing and trust of artwork transaction are realized based on the block chain.

Description

Technical Field

[0001] The present invention relates to the field of blockchain technology, and particularly to a method for storing evidence and tracing the origin of artworks on the 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 appraisals, evaluations, and negotiations, and relevant transaction records and artwork circulation information are mostly stored in paper or non-standard electronic formats, which results in insufficient transaction transparency, increases the difficulty of tracing the origin and verifying the rights of artworks, and poses challenges to the security and trust of artwork transactions.

[0003] With the continuous development of network technology, artwork trading platforms have gradually improved, providing more convenient, transparent, and efficient channels for buying and selling artworks. Although artwork trading platforms have solved some problems of traditional trading methods and brought convenience, there are still risks in copyright protection and tracing. The opacity of trading platforms may conceal fraudulent and illegal trading behaviors, and user privacy protection cannot be guaranteed. In addition, trading platforms are centralized systems with a single point of failure risk. Once the core system has problems, the entire trading network may be paralyzed, and it is difficult to achieve the verification of rights and tracing of artworks in a centralized system, resulting in difficult copyright protection.

[0004] In view of this situation, an artwork blockchain trading system has emerged and is developing in a more secure, intelligent, and reliable direction. However, despite the progress, there are still obvious deficiencies in the existing systems in terms of security, privacy protection, and transaction efficiency, which to a certain extent restricts the further development of artwork transactions. Therefore, in today's artwork trading market, the issues of verifying rights, tracing the origin, and trust have always been the key issues restricting its development. Summary of the Invention

[0005] The purpose of the present invention is to realize the issues of verifying rights, tracing the origin, and trust in artwork transactions based on the blockchain, and provide a method for storing evidence and tracing the origin of artworks on the blockchain.

[0006] To achieve the above invention purpose, the embodiments of the present invention provide the following technical solutions:

[0007] A method for storing evidence and tracing the origin of artworks on the blockchain, comprising the following steps:

[0008] Step 1, the artwork on-chain stage: The seller signs the artwork to be put on the chain, and broadcasts the signature and the perceptual hash value of the artwork to the blockchain; the committee verifies whether the artwork is uploaded repeatedly. If there is no repeated upload, the artwork is officially put on the chain and sold on the trading platform designated by the seller.

[0009] Step 2, the art transaction stage. The purchaser places an order to buy an artwork. The trading platform publishes the transaction information to the blockchain. The seller checks whether the transaction information is consistent with the information uploaded to the chain. If it is consistent, the seller ships the goods. The purchaser verifies the received artwork. If the verification is successful, the transaction is completed.

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

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0012] This solution combines blockchain technology with art transactions, adopts an efficient and resource-friendly Delegated Proof of Stake (DPOS) consensus mechanism, significantly reduces computing and storage consumption, and is particularly suitable for resource-constrained device environments. Through the immutable feature of the blockchain, the system meticulously records the transaction history and transfer information of each artwork, ensuring transaction transparency and traceability, and effectively alleviating the information asymmetry problem in the art market. The solution introduces advanced technologies such as neural networks, perceptual hash values, and Hamming distance algorithms to generate a unique and counterfeit-proof digital identifier for each artwork. During the transaction process, the solution also combines digital signature technology to ensure the non-repudiation and integrity of the data, thus constructing a secure and reliable transaction authentication system. In addition, the integrated application of smart contracts realizes the automated execution of art transactions, greatly improving transaction efficiency while reducing the risk of human operation. Combining the decentralized feature of blockchain technology, a fair and transparent transaction dispute handling mechanism is established, further ensuring transaction fairness and comprehensive protection of user rights and interests. This solution not only improves the efficiency and security of art transactions but also provides an innovative solution framework for art traceability and copyright protection. Brief Description of the Drawings

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 It is the flowchart of the method of the present invention;

[0015] Figure 2 It is the schematic diagram of the Merkle tree of the embodiment of the present invention. Detailed Embodiments

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and illustrated in the drawings here 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 the selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0017] It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present invention, terms such as "first" and "second" are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance or implying any such actual relationship or order between these entities or operations. In addition, terms such as "connected" and "coupled" can be directly connected between components or indirectly connected through other components.

[0018] Embodiment 1:

[0019] This solution plans to use a public chain to store and trace artworks. The system architecture consists of a large number of lightweight nodes (i.e., users, including seller Ua, buyer Ub, and express center E) and several non-lightweight nodes on the blockchain (including trading platform S, regulatory department RA, and inspection agency VI). Among them, multiple regulatory departments, inspection agencies, and trading platforms form a committee. In each transaction, a part is selected from the committee as the verification committee by voting, and one is selected as the signature committee. These participants jointly form a blockchain network and adopt the Delegated Proof of Stake (DPOS) consensus mechanism. The core of the DPOS consensus mechanism is that the trading platform, regulatory department, and inspection agency are responsible for block generation and network maintenance, while users only have the function of checking. As lightweight nodes, users only store the block header information of the blockchain and are granted the permission to view blockchain data, mainly used to verify the transfer of ownership of artworks. The trading platform, regulatory department, and inspection agency jointly determine the permission to upload and modify blockchain information and are responsible for data entry, update, and maintenance. This permission allocation mechanism ensures data transparency while effectively saving blockchain resources and improving the computing efficiency and response speed of the system.

[0020] This solution needs to include 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 identity identifier of the seller, the "TP" column is used to store the identity identifier of the trading platform, the "T" column is used to store the time node, the "PHV" column is used to store the perceptual hash value of the artwork, the "To" column is used to store the identity identifier of the purchaser, and Sign TP column is used to store the digital signature of the trading platform, and Sign From column is used to store the digital signature of the seller, the "EC" column is used to store the identity identifier of the express delivery center, and the "Rm" column is used to store some remarks of the transaction information. Sign TP is to sign the information in the columns of From, TP, T, PHV, To, and Rm, and Sign From is to sign the information in the columns of From, TP, T, PHV, and To. Assume that the public-private key pair of the seller Ua is (Sk Ua , Pk Ua ), the public-private key pair of the purchaser Ub is (Sk Ub , Pk Ub ), and the public-private key pair of the express delivery center E is (Sk E , Pk E ).

[0021] The present invention is realized through the following technical solutions. As Figure 1 shown, a method for storing evidence and tracing the origin of artworks on the blockchain includes the following steps:

[0022] Step 1, the stage of artworks being stored on the blockchain. The seller signs the artworks to be stored on the blockchain, and broadcasts the signature and the perceptual hash value of the artworks to the blockchain; the committee verifies whether the artworks are stored on the blockchain repeatedly. If there is no repeated storage on the blockchain, the artworks are officially stored on the blockchain and are sold on the trading platform designated by the seller.

[0023] Any artwork needs to be stored on the blockchain when it is sold for the first time. After being stored on the blockchain, the artwork can undergo multiple transactions on the blockchain. It is necessary to ensure that the perceptual hash value of the artwork remains fixed under each transaction, and the purchaser of this transaction is the seller of the next transaction. The specific steps of the said Step 1 include the following steps:

[0024] Step 1-1, the seller Ua calculates the perceptual hash value PHV A of the artwork A, and obtains Sign Ua by signing; after the committee determines that the artwork A is not a counterfeit, it calculates the perceptual hash value PHV A ` of the artwork A.

[0025] Specifically for the said Step 1-1, it includes the following process:

[0026] (1) The seller Ua takes multi-angle dynamic photos of the art piece A through a terminal device (such as a mobile phone). During the shooting, RGB fill light is used, and at the same time, the art piece A is rotated uniformly. A 10 - 15 - second video containing multi - angle and fill - light changes is obtained. Multiple frames of images with different angles and lighting conditions are extracted from the video. The mobile phone gyroscope's angle changes 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 also needs to be collected synchronously during the shooting: the mobile phone gyroscope's trajectory (i.e., the rotation angle and speed during shooting), the depth information of the ToF sensor (i.e., the distance from the object surface), and the reflection sequence (i.e., the light - reflecting characteristics of the art piece's surface under the mobile phone's fill light). Multiple frames of images are detected through the Laplacian variance, and 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 art piece A based on the feature vectors. The MobileNet network is deployed in the blockchain network, and users can directly use it through the port without deploying the model. The seller Ua uses his own private key Sk A to sign the information b = {From, TP, T, PHV, To}. The specific content of the information b is b = {ID Ua , ID Ua , the time T1 when the seller applies to upload to the chain, PHV S , null value}, where ID A represents the identity identifier of the seller Ua, ID Ua represents the identity identifier of the trading platform S, and PHV S represents the perceptual hash value of the art piece A. After the seller Ua signs the information b with the private key Sk A , the digital signature Sign Ua of the seller Ua is obtained, Sign Ua = Sign(Sk Ua , ID Ua || ID S || T1 || PHV A || null value).

[0028] (3) The seller Ua sends multiple frames of images, the mobile phone gyroscope's trajectory, the depth information of the ToF sensor, and the reflection sequence to the committee. The committee uses LSTM to analyze the reflection changes between multiple frames of images, detect the naturalness of the art piece's material, and judge whether it is a forgery, which can resist attacks from 3D replicas to the greatest extent. For example, if the reflection change undergoes a mutation, it is judged that the art piece is a replica, because usually the light reflection of oil paint is a gradual change, and only the light reflection of printed matter is a mutation; another example is that if the mobile phone gyroscope's trajectory does not match the perspective change of multiple frames of images, such as the mobile phone is stationary but the picture moves, then the art piece is judged to be a replica.

[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] Step 1-2: Seller Ua broadcasts the on-chain information c to the blockchain, indicating his intention to sell 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 they are consistent, proceed to the next step after successful comparison.

[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 step 1-4).

[0034] 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 upload 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 AThe Hamming distance Hd with each existing Perceptual Hash Value PHV on the blockchain i Assume that there are n Perceptual Hash Values of artworks existing on the blockchain, then there is PHV i ∈{PHV1, PHV2,..., PHV i}. 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. n}

[0037]

[0038] Among them, m is the length of the Perceptual Hash Value; j is the number of digits of the Perceptual Hash Value length; PHV A (j) is the Perceptual Hash Value of PHV A at the j-th digit; PHV i (j) is the Perceptual Hash Value of PHV i at the j-th digit.

[0039] (2) The verification committee sets a threshold t for the Hamming distance to determine whether the artwork A has been uploaded to the blockchain. If , it means that the artwork A has not been uploaded to the blockchain, and the upload information c is put into the transaction pool; otherwise, it means that the artwork A has been uploaded to the blockchain, and there may be a problem of plagiarism for this artwork, and the upload of this artwork is rejected.

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

[0041] The non-verification committee in the committee obtains the upload information c from the transaction pool and ensures that the content included in the upload information c meets the requirements of the blockchain protocol, such as correct format, valid timestamp, etc. Then a Byzantine Fault Tolerance vote is carried out. If more than 2 / 3 of the non-verification committee votes are obtained, a consensus is reached. The verification committee takes out the upload information c that has reached a consensus from the transaction pool and integrates it into a new block. The verification committee broadcasts the generated new block to the entire blockchain network, and the artwork A is officially uploaded to the blockchain.

[0042] Steps 1 - 6, the trading platform S publicly displays and sells the artwork A.

[0043] After the artwork A is uploaded to the blockchain, the trading platform S verifies whether the TP in the upload information c is its own identity identifier ID S . If so, after the trading platform S and the seller Ua negotiate and confirm the price, a front view is selected from multiple frames of images, and the front view, Perceptual Hash Value PHV A and price of the artwork A are uploaded to the server for public display and sale on the trading platform S.

[0044] Step 2, the art transaction stage. The purchaser places an order to buy an artwork; the trading platform publishes the transaction information to the blockchain; the seller checks whether the transaction information is consistent with the information uploaded to the chain. If it is consistent, the seller ships the goods; the purchaser verifies the received artwork. If the verification is successful, the transaction is completed.

[0045] After the artwork is uploaded to the chain, the transaction mainly takes place on the trading platform S, and the blockchain is mainly recorded as a distributed ledger. As lightweight nodes, the purchaser and the seller need to locally store the following information in each transaction: the hash value of the block where the artwork A is located (Previous Block Hash), the Merkle root of the block (Merkle Root), the timestamp T1` when the block is generated, and the signature of the verification committee (Signature).

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

[0047] Step 2-1, the purchaser Ub requests the trading platform S to check whether the information c uploaded to the chain of the artwork A is true. If it is true, the purchaser makes a payment.

[0048] The purchaser Ub intends to buy the artwork A on the trading platform S and requests the trading platform S to check the information c uploaded to the chain of the artwork A. The trading platform S retrieves the 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 the transaction number r1 of the artwork A from the blockchain and sends them to the purchaser Ub.

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

[0050] (1)The purchaser Ub performs a hash process on the obtained information c uploaded to the chain 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), null, null}, initiate a query request to the verification committee and send the transaction number r1. The query request includes 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 the transaction number r1, and returns the Merkle1 path of Artwork A as a response to the purchaser Ub.

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

[0053] As an example, as Figure 2 shown, assume that the purchaser Ub intends to query Artwork A. After obtaining the information of Artwork A, it performs a hash process to obtain the hash value N0, and sends N0 to the verification committee to initiate a query request. The verification committee sends the found Merkle path {N0→N4→N5} and the hash values of the nodes {N0, N1, N4, N5} to the purchaser Ub according to N0; the purchaser Ub calculates the hash values layer by layer upward, first calculates N4 through N0 and N1, and then calculates Root through N4 and N5; compare the calculated Root (i.e., the Merkle1 root) with the Merkle root stored locally. If they are the same, the verification is successful.

[0054] 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 trading platform S publishes the transaction information d to the blockchain to realize the transfer of ownership of Artwork A. The transaction information is d = {From, TP, T, PHV, To, Sign TP 、Sign From 、EC、Rm}, and the specific content of the transaction information d is d = {ID Ua 、ID S 、The time T2 when the purchaser makes the payment, PHV A 、ID Ub 、Sign(Sk S ,ID Ua ||ID S ||T2||PHV A ||ID Ub )、Sign(Sk Ua ,ID Ua ||ID S ||T1||PHVA ||ID Ub )), null, null}, where Sk S represents the private key of trading platform S, and Sign S = Sign(Sk S , ID Ua ||ID S ||T2||PHV A ||ID Ub ). The committee uses the public key Pk of trading platform S S to verify Sign S . After verification, the obtained ID S If it is consistent with the ID in transaction information d S , then the committee successfully verifies the identity of trading platform S, and the transaction information d is officially recorded on the blockchain. Trading platform S notifies seller Ua to ship the goods, sends the transaction number r2 to seller Ua, and provides the receiving address of buyer Ub.

[0056] Step 2-3: Seller Ua verifies through the transaction information d on the blockchain whether the ownership of art A has been transferred. If the transfer is successful, then ship art A.

[0057] The verification process is as follows:

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

[0059] (2) Seller Ua calculates the Merkle2 root layer by layer through the Merkle2 path, and compares the calculated Merkle2 root with the Merkle root stored locally. If they are the same, it means that the transfer of ownership of art A is successful, and then ship the goods.

[0060] (3) Seller Ua takes art A to express delivery center E. Express delivery center E extracts the features of art A to obtain the feature vector (the same as step 1-1), and calculates the perceptual hash value of the feature vector to obtain PHV A ``, and sends PHV A `` to the committee. The committee searches on the blockchain based on PHV A `` to find whether there is a similar PHV A . If there is a similar one, then send the transaction information d of art A and the Merkle2 path to express delivery center E.

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

[0062] Step 2-4, the courier center E applies to upload the shipping information e, and the seller Ua tells the transaction platform S the courier number.

[0063] The courier center E sends the shipping information e = {From, TP, T, PHV, To, Sign TP , Sign From , EC, Rm} and the digital signature Sign E of the courier center to the committee for applying to upload. The specific content of the shipping information e is e = {ID Ua , ID S , T2, PHV A , ID Ub , Sign(Sk S , ID Ua || ID S || T2 || PHV A || ID Ub ), Sign(Sk Ua , ID Ua || ID S || T1 || PHV A || ID Ub || null value), ID E , null value}, where ID E is the identity identifier of the courier center E. Sign E = (Sk E , ID E ) is the digital signature of the courier center E, and Sk E is the private key of the courier center E.

[0064] After receiving the shipping information e, the committee uses the public key Pk E of the courier center E to E decrypt the signature Sign E to obtain ID E . By comparing the ID E obtained by decryption with the ID in the shipping information e, if they are the same, the committee agrees to upload the shipping information e. After uploading, the committee sends the transaction number r3 to the seller.

[0065] The seller Ua sends the transaction number r3 to the committee, and 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 hashing the shipping information e and the Merkle root stored locally. E If so, pay the postage and obtain the express number. At this time, if the artwork A is lost or forged, the liable party is the express center E. The seller Ua notifies the trading platform S of the express number, and the trading platform S verifies the express order number to confirm whether the seller Ua has shipped the goods.

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

[0067] The buyer Ub signs for the artwork A in person, extracts the features of the artwork A to obtain the feature vector, and calculates the perceptual hash value PHV based on the feature vector. A *, compare PHV A * with the PHV in the on-chain information c A to see if they are similar (the similarity comparison method is the same as in Step 1-3). If they are similar, it means that the artwork A has not been tampered with, forged, etc. At this point, the transaction of the artwork A is completed.

[0068] Step 2-6, if the verification is not successful, the buyer Ub clicks to reject on the trading platform S, and the trading platform S restores the transaction information f to the blockchain. At this point, the transaction is completed.

[0069] If they are not similar, the buyer Ub clicks to reject on the trading platform S, and the trading platform S restores the transaction information f = {ID Ua 、ID S 、T2、PHV A 、null value、Sign S 、Sign Ua 、ID E 、us}, where us indicates that the transaction is not successful. To restore to the state before the buyer Ub made the purchase, Sign S = Sign(Sk S ,ID Ua ||ID S ||T2||PHV A ||null value||us), To restore to the state before the buyer Ub made the purchase, broadcast the transaction information f to the committee, and the committee verifies whether the IDs in Sign S are the same as the IDs in the transaction information f. If they are the same, put the transaction information f on the chain. After putting it on the chain, the committee sends the transaction number r4 to the seller.

[0070] In summary, the three parties to the transaction (seller Ua, trading platform S, and buyer Ub) will sign a smart contract, which details the rights and obligations of each party, ensuring the transparency, fairness, and automated execution of the transaction process. Specifically, the seller Ua needs to pay a certain amount of deposit to the trading platform S as a guarantee for fulfilling the contract. If the seller Ua fails to deliver the goods within the agreed time, the smart contract will automatically trigger a deduction mechanism to deduct the corresponding penalty from the deposit, thereby ensuring the smooth progress of the transaction and the protection of the rights and interests of all parties. If the buyer Ub pays the trading platform S but finds that the trading platform S has not updated the information on the blockchain for a long time, the trading platform S will be subject to corresponding penalties. If the express center EC loses the art piece during the transportation process, the express center EC shall bear all responsibilities.

[0071] Step 3, the art piece traceability stage. The inquirer queries the historical records of the art piece through the trading platform or the blockchain, including the initial time of uploading to the chain and the information of previous transactions.

[0072] The art piece traceability process is realized through the blockchain network. The inquirer L inputs the perceptual hash value PHV of the art piece A A (at this time, the inquirer L is a person who has participated in the transaction of the art piece A) or the identity identifier ID of the seller Ua Ua (at this time, the inquirer L is a person who has not participated in the transaction of the art piece A) to query the complete transfer history of the art piece A. The blockchain verifies the continuity of the transaction and the integrity of the information, and finally presents the key information in a visual manner.

[0073] The specific steps of the said Step 3 include the following steps:

[0074] Step 3-1, the inquirer L inputs the perceptual hash value PHV of the art piece A through the trading platform S or the blockchain browser A or the identity identifier ID of the seller Ua Ua , as the keyword for traceability. The trading platform S or the blockchain node retrieves all the historical records related to the art piece A according to the input keyword. These historical records include: the initial information uploaded to the chain {ID Ua , the application time of uploading to the chain T1, the perceptual hash value PHV A}, and the information of previous transactions {ID Ub , multiple transaction times T2, Rm}.

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

[0076] (1) Verify whether the buyer Ub of the k-th transaction is the same person as the seller Ua of the (k + 1)-th transaction.

[0077]

[0078] If there are records of unsuccessful transactions , In the Rm column, it is us.

[0079] (2)Ensure that the Perceptual Hash Value (PHV) of Artwork A A remains unchanged in each transaction to verify the uniqueness of Artwork A.

[0080]

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

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

[0083] (2)Use the public key Pk of the trading platform S S to decrypt the digital signature Signature to obtain the information digest Digest`. Verify whether the information digest Digest` is consistent with the Digest in the record. If they are consistent, it means the record has not been tampered with.

[0084] Step 3-4: Finally, the traceability result is presented to the querier L in a visual manner. The traceability result includes: the initial seller, the buyers and sellers in previous transactions, and the times of previous transactions.

[0085] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. Method for storing evidence and tracing the origin of artworks, characterized in that, Including the following steps: Step 1, the artworks on-chain stage: The seller signs the artworks to be put on-chain, broadcasts the signature and the perceptual hash value of the artworks to the blockchain. The committee verifies whether the artworks are put on-chain repeatedly. If not, the artworks are officially put on-chain and sold on the trading platform designated by the seller. Step 2, the artworks trading stage: The purchaser places an order to buy the artworks. The trading platform publishes the transaction information to the blockchain. The seller checks whether the transaction information is consistent with the information on-chain. If it is consistent, the seller ships the goods. The purchaser verifies the received artworks. If the verification is successful, the transaction is completed. Step 3, the artworks traceability stage: The querier queries the historical records of the artworks through the trading platform or the blockchain, including the initial on-chain time and previous transaction information.

2. The method for storing evidence and tracing the origin of artworks on the blockchain according to claim 1, wherein The specific steps of Step 1 include the following steps: Step 1-1, the seller Ua calculates the perceptual hash value PHV of the artwork A A , and signs it to obtain Sign Ua ; after the committee determines that the artwork A is not a counterfeit, it calculates the perceptual hash value PHV of the artwork A A `; 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. Step 1-3, after the committee receives the on-chain information c, it uses the public key Pk of the seller Ua Ua to decrypt and view the PHV in the on-chain information c A to check if it is the same as the PHV in Ua Sign, and whether it is similar to the PHV A . Also, check if the ID in the on-chain information c A is the same as that in Sign Ua . After all the comparisons are successful, proceed to the next step; Ua ​ Step 1-4: The verification committee verifies whether the artwork A is put on-chain repeatedly. Step 1-5: After the committee reaches a consensus, the artwork A is officially put on-chain. Step 1-6: The trading platform S publicly displays and sells the artwork A.

3. The method for uploading, storing evidence, and tracing the origin of artworks according to claim 2, wherein In the step 1-1, the seller Ua calculates the perceptual hash value PHV of the artwork A A , and signs it to obtain Sign Ua . The steps include: The seller Ua uses its own private key Sk Ua to sign the information b = {ID Ua 、ID S 、T1、PHV A 、To} to obtain the digital signature Sign Ua = Sign(Sk Ua ,ID Ua ||ID S ||T1||PHV A ||To), where ID Ua is the identity identifier of the seller Ua, ID S is the identity identifier of the trading platform S, T1 is the time when the seller applies to go on the chain, PHV A is the perceptual hash value of the art A, and To is the identity identifier of the purchaser; To is a null value in the information b 4. The method for uploading an artwork to the blockchain for evidence storage and traceability according to claim 3, wherein In the said step 1-2, the on-chain 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 trading platform S, EC is the identity identifier of the express center, and Rm is the remark; in the on-chain information c, To, Sign S , EC, and Rm are all null values.

5. The method for on-chain storage, certification and traceability of artworks according to claim 4, wherein The specific steps of Step 2 include the following steps: Step 2-1: The purchaser Ub requests the trading platform S to check whether the on-chain information c of the artwork A is true. If it is true, the purchaser pays. 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: The seller Ua verifies through the transaction information d on the blockchain whether the ownership of the artwork A has been changed. If the change is successful, the seller ships the artwork A. Step 2-4: The express delivery center E applies to put the delivery information e on-chain, and the seller Ua tells the trading platform S the express delivery number. Step 2-5, the purchaser Ub verifies the perceptual hash value PHV of the received artwork A A *, if the verification is successful, the transaction of the artwork A is completed; Step 2-6: If the verification is not successful, the purchaser Ub clicks to reject on the trading platform S, and the trading platform S restores the transaction information f to the blockchain. Thus, the transaction is completed.

6. The method for uploading, storing, certifying and tracing artworks according to claim 5, characterized in that, The specific content of Step 2-1 is as follows: After the artworks are put on-chain, in each transaction, the information that the user needs to store locally includes: the hash value of the block where the artwork A is located, the Merkle root, the timestamp T1` when the block is generated, and the signature Signature of the verification committee. The purchaser Ub intends to buy the artwork A on the trading platform S, requests the trading platform S to check the on-chain information c of the artwork A, and the trading platform S retrieves the on-chain information c and the transaction number r1 of the artwork A from the blockchain and sends them to the purchaser Ub. After receiving the on-chain information c, the purchaser Ub performs a hash process to obtain the hash value H, and verifies the received on-chain information c through the hash value H. If the verification is successful, the purchaser Ub places an order for the artwork A on the trading platform S and completes the payment. The verification process is as follows. (1) The purchaser Ub performs a hash process on the uploaded information c obtained, and gets 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 includes the Merkle path query for the artwork A; (2) After receiving the query request, the verification committee finds the block containing the artwork A from the blockchain according to the transaction number r1, and returns the Merkle1 path of the artwork A as a response to the purchaser Ub. (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; compares the calculated Merkle1 root with the Merkle root stored locally. If they are the same, it proves that the blockchain information c of the artwork A is stored in the blockchain and is correct, indicating successful verification.

7. The method for uploading and storing evidence and tracing the origin of artworks according to claim 5, 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 purchaser Ub makes the payment, Sign S = Sign(Sk S , ID Ua || ID S || T2 || PHV A || ID Ub || Rm), and in the transaction information d, EC and Rm are null values; after being uploaded to the chain, the trading platform S sends the transaction number r2 to the seller Ua and notifies the seller Ua to ship the goods.

8. The method for uploading, storing, authenticating and tracing artworks according to claim 7, wherein The specific steps of step 2-3 are as follows: (1) The seller Ua sends a query request to the committee and sends the transaction number r2 of the artwork A to the committee; the committee queries the transaction information d of the artwork A and the Merkle2 path of the artwork A through the transaction number r2, and returns the committee transaction information d and the Merkle2 path as a response to the seller Ua; (2) The seller Ua calculates the Merkle2 root layer by layer through the Merkle2 path, compares the calculated Merkle2 root with the Merkle root stored locally. If they are the same, it means that the transfer of ownership of the artwork A is successful, and the goods are shipped; (3) The seller Ua takes the art A to the express center E. The express center E extracts the features of the art A to obtain a feature vector, and calculates the perceptual hash value of the feature vector to obtain the PHV A ``, and sends the PHV A `` to the committee; Based on the PHV A ``, the committee searches on the blockchain to see if there is a similar PHV A . If so, it sends the transaction information d of the art A and the Merkle2 path to the express center E; (4) The express delivery center E checks the transaction information d and the Merkle2 path, calculates the Merkle2 root layer by layer, compares the calculated Merkle2 root with the Merkle root stored locally. If they are the same, the artwork A is packaged and shipped.

9. The method for storing evidence and tracing the origin of artworks on the blockchain according to claim 7, wherein In the said 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 is the identity identifier of the express center E, and Rm is a null value.

10. The method for storing and tracing the blockchain of artworks according to claim 9, 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 perceived hash value PHV based on the feature vector A *, compared with PHV A * The same as PHV in the link information c A Are they similar? If they are similar, it means that artwork A has not been tampered with or forged, and the transaction of artwork A is now completed; The specific steps 2-6 are as follows: The purchaser Ub clicks "reject" on the trading platform S, and the trading platform S restores and uploads the trading information f = {ID Ua 、ID S 、T2、PHV A 、null value、Sign S 、Sign Ua 、ID E 、us}, where us indicates that the transaction is unsuccessful. To restore to the state before the purchaser Ub made the purchase, Sign S = Sign(Sk S ,ID Ua ||ID S ||T2||PHV A ||null value||us).

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