WO2021137392A1

WO2021137392A1 - Blockchain-based video asset management method

Info

Publication number: WO2021137392A1
Application number: PCT/KR2020/012720
Authority: WO
Inventors: 신상호; 유수빈; 박윤하; 김대수; 전재현; 김지성; 조정화; 손애선
Original assignee: 재단법인 경주스마트미디어센터; 주식회사 우경정보기술; 주식회사 엘토브
Priority date: 2019-12-30
Filing date: 2020-09-21
Publication date: 2021-07-08
Also published as: KR102234542B1; JP2023521266A

Abstract

The present invention relates to a blockchain-based audiovisual work management method whereby, in a multiple-participant environment, an audiovisual work is managed using a blockchain, secret-sharing and a hash function, and thus copyright disputes over audiovisual works may be fundamentally prevented. According to one embodiment of the present invention, unlike the conventional way whereby the required time and computation amount increases in proportion to the number of participants when using a PKI or hash function having a key, in order to generate a blockchain, the present invention uses secret-sharing and finite field computation whereby the required time and computation amount remains constant regardless of the number of participants, and thus is very efficient when generating a blockchain node in a multiple-participant environment, and has an advantage of being excellent in terms of spatial and temporal aspects also for hardware manufacturing in the future. Further, the present invention has an advantage whereby separate key management is unnecessary.

Description

Blockchain-based video asset management method

The present invention relates to a block chain-based video work management method that can fundamentally prevent copyright disputes over video works by managing video works using block chains and secret sharing and hash functions in a multi-participant environment.

Copyright disputes over works have been going on for a long time, and the majority of disputes exist in the field of sound sources and computer programs. However, as the multi-channel network (MCN) industry that can systematically manage YouTube and the one-person media creation industry by revitalizing and expanding its base, is rapidly emerging, various related issues are occurring. In particular, copyright disputes between MCN companies and creators regarding single media creators managed within the MCN company are on the rise.

However, there is a lack of technology that can fundamentally prevent such disputes, and the method to ensure transparency and reliability in the contract for the production of video works and the actual production process is weak.

On the other hand, as a data storage technology in a distributed ledger environment, block chain provides high transparency and reliability to users in terms of data management because it is impossible to forge or falsify data stored in a specific block using a hash function. There is no need for a central administrator because the blocks connected in the form are distributed and stored, and the maintenance cost for safe data storage and management is relatively low.

The existing block chain creation method is performed through widely known cryptographic techniques and distributed consensus. The encryption technique mainly uses a cryptographic hash function in which a secret key exists or a public key infrastructure (PKI).

The problems caused by this are as follows.

First, it is a problem that requires a large amount of computation when using PKI. PKI mainly uses digital signature and public key cryptographic algorithms such as DSA, RSA, ECC, or EC-DSA. The speed and the amount of computation are increasing exponentially. If the capacity of the data stored in the block increases, the time and amount of computation required for the operation increase accordingly, and as a result, separate software or hardware must be newly developed and constructed in the related field, thereby increasing the cost to solve this problem. will do In addition, in the case of ECC, there is a disadvantage that it cannot be used for storing nodes in the block chain right away because it has only recently entered the commercialization stage and checked various safety.

Second, it is a problem of managing various keys. When data in the block chain is stored through a hash function or PKI in which a private key exists, a new private key (a public key must also be issued if necessary) for participating users must be issued and safely distributed to users, and users must A key management policy and system that can properly address the loss or other issues are needed. In particular, in the case of a hash function in which a secret key exists, a secret key must exist for each authorized user for a specific block chain node. Therefore, if the number of block chain nodes and authorized users increases, the corresponding key will inevitably increase exponentially. , since a more complex type of key management policy must be introduced along with the additional requirement of a key management system, the cost to solve this problem increases. Since PKI is also performed based on digital signature and public key cryptography, key management is very important, and security measures must be prepared for this when designing a system.

Third, there is the issue of exposure of data stored in the blockchain. The existing block chain node creation technique can check the data stored in the block chain by using the participant's private key. However, if a participant loses the secret key or is attacked by a malicious attacker, sensitive information stored in the block chain node may be exposed as it is. Moreover, if the stored data in the block chain is a secret, managing it fundamentally depending on the secret key has a problem in that the cost of construction and maintenance in terms of the system increases.

An object of the present invention is to provide a block chain-based video work management method that can fundamentally prevent copyright disputes over video works by managing video works using block chains and secret sharing and hash functions in a multi-participant environment. .

A block chain-based image asset management method according to an embodiment of the present invention,

Deriving a _{hash value (OV H} ) by receiving the image work data including the work content and work result from the participant terminal, and applying a hash function to the received image work data; Reducing polynomial (Finite Field) with the number of participants (n) related to the image work data to be stored in the block chain, the identifiers of the participants (P _i , 1≤i≤n), and the identifiers of the participants as input values ( a preprocessing step of setting f(x)); By inputting the identifier (P _i ) into the irreducible polynomial (f(x)), a hash fragment value (f(P _i )) is generated, and the identifier (P _i ) and hash fragment value (f(P _i )) Distributing an ordered pair of (P _i , f(P _i )) to the participants, respectively, and an additional identifier (P _n+1 ) and an additional hash fragment value (f(P _n+1 )) other than the participants’ identifiers. and a secret sharing step of storing the ordered pair (P _n+1 , f(P _{n+1 )) in the node.}

In the block chain-based image asset management method according to an embodiment of the present invention, the ordered pair (P _i , f(P _i _{)) of the identifier (P i} ) and the hash fragment value (f(P _i )) is converted into a Lagrange interpolation formula An additional hash fragment value generated by inputting _{the additional identifier (P n+1} ) to the derived reduced polynomial (f'(x)) to derive the reduced polynomial (f'(x)) by inputting it into a formula using The method may further include a proof-of-work step of performing proof-of-work by comparing f'(P _n+1 )) with an additional hash fragment value f(P _{n+1 ) stored in the node.}

In the block chain-based image asset management method according to an embodiment of the present invention, the irreducible polynomial (f(x)) may be defined by the following equation (1).

Formula (1):

(Where, t is a threshold value and, a _j is the coefficient value inserted as part of the hash value (OV _H) to be inserted in a block chain, the bit unit after parsing the binary hash value (OV _H), mod is It is a remainder function to find the remainder of arbitrary division, GF is a polynomial belonging to Galois feild, and k means the number of bits)

In the block chain-based image asset management method according to an embodiment of the present invention, _{at least a part of the hash value (OV H} _{) to be inserted into the block chain is a coefficient value (a j} ) in the irreducible polynomial (f(x)). If it cannot be inserted, another irreducible polynomial (g(x), h(x), ...) is additionally set, _{until all transformed binary data of the hash value (OV H} ) are inserted as coefficient values. It is possible to repeatedly perform the secret sharing step.

In the block chain-based image asset management method according to an embodiment of the present invention, the irreducible polynomial (f'(x)) may be defined by the following Equation (2).

Equation (2):

(where x is the variable of the polynomial f'(x), x _o is the identifier (P _o ), x _j is the identifier (P _j ), y _j is the hash fragment value (f(P _j )), Π is a function that means product)

In the block chain-based video work management method according to an embodiment of the present invention, the additional identifier (P _n+1 ) uses at least one of a nonce and a time stamp in a block chain system. Therefore, it can be specified according to the operation policy of the blockchain system.

In the block chain-based image asset management method according to an embodiment of the present invention, in the pre-processing step, a threshold value (t) for starting the proof-of-work step is set, and the threshold value (t) or more among n participants is collusive. Proof of work can be performed by submitting an ordered pair (P _i , f(P _i )) of one’s own identifier (P _i ) and hash fragment value (f(P _{i )) to the blockchain system.}

In the block chain-based image copyright management method according to an embodiment of the present invention, the threshold value t may be set to a higher stake for a certain participant than other participants.

Deriving a _{hash value (OV H} ) coupled with a computing device, receiving image work data including at least one of work content and work result from a participant terminal, and applying a hash function to the received image work data ; The number of participants (n) related to the video work data to be stored in the block chain, the identifiers of the participants (P _i , 1≤i≤n), and the irreducible polynomial (f) in a finite field with the identifiers of the participants as input values (x)) a pre-processing step to set; By inputting the identifier (P _i ) into the irreducible polynomial (f(x)), a hash fragment value (f(P _i )) is generated, and the identifier (P _i ) and hash fragment value (f(P _i )) Distributing an ordered pair of (P _i , f(P _i )) to the participants, respectively, and an additional identifier (P _n+1 ) and an additional hash fragment value (f(P _n+1 )) other than the participants’ identifiers. A secret sharing step of storing the ordered pair (P _n+1 , f(P _{n+1 )) in the node;} By inputting the ordered pair (P _i , f(P _i )) of the identifier (P _i ) and the hash fragment value (f(P _i )) into the equation using the Lagrange interpolation equation, the reduced polynomial (f'(x)) is derived. and the additional hash fragment value (f'(P _n+1 _{)) generated by inputting the additional identifier (P n+1} ) to the derived irreducible polynomial (f'(x)) and the additional hash fragment stored in the node In order to execute the proof-of-work step of performing proof-of-work by comparing the values f(P _{n+1 ), it may be implemented as a computer program stored in a computer-readable recording medium.}

According to the block chain-based image copyright management method according to an embodiment of the present invention,

The actual original data (work contents (WR) and work result (CR)) are encrypted and stored in storage, _{a part of the hash value (OV H} ) of the original data is stored in the node, and the data stored in the block chain node is It is impossible to arbitrarily forge or falsify, and all the participants who participated in the work production process check the work results and work contents before storage in the node through the participant terminals. transparency and reliability can be ensured.

In addition, by having some of all participants in the production of the work check the work results and contents of the work drawn by a specific participant, it is possible to present an opinion on whether the work is being performed correctly and to clearly record the production process of the work.

In addition, when using a hash function or PKI with a key to create the existing block chain, the required time and amount of computation increase in proportion to the number of participants, but it is related to the number of participants using secret sharing and finite-body operation. Since the required time and amount of computation are constant, it is very efficient when creating a block chain node in a multi-participant environment, and it has the effect of being excellent in terms of space and time even when manufacturing hardware in the future. In addition, there is an effect that separate key management is not required.

1 is a diagram illustrating a block chain-based image asset management system according to an embodiment of the present invention.

2 is a flowchart illustrating a block chain-based image asset management method according to an embodiment of the present invention.

3 is a view for explaining a process of generating _{a coefficient value a j} of the irreducible polynomial (f(x)) _{from a hash value (OV H} ) in the step of performing secret sharing according to an embodiment of the present invention.

Figure 4 is the Identifier (P _i) the irreducible polynomial (f (x)) by the identifier (P _i) and the hash fragment value (f (P _i)) entered in the performing step shared secret according to an embodiment of the present invention It is a diagram for explaining the process of distributing the ordered pairs (P _i , f(P _{i )) to the participants, respectively.}

5 is a diagram for explaining a work proof step according to an embodiment of the present invention.

6 is a diagram illustrating a computing device according to an embodiment of the present invention.

Since the present invention can apply various transformations and can have various embodiments, specific embodiments are illustrated and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present invention, terms such as 'comprising' or 'having' are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

As a data storage technology in a distributed ledger environment, block chain provides high transparency and reliability to users in terms of data management and provides high transparency and reliability to users in terms of data management because it is impossible to forge or falsify data stored in a specific block using a hash function. Since the connected blocks are distributed and stored, there is no need for a central administrator, and the maintenance cost for safe data storage and management is relatively low.

In the present invention, after performing a contract between the parties or multiple participants in order to produce a specific work by using this block chain technology, all persons participating in the contract can participate in the work performed by themselves in the block chain-based copyright management system. Record and upload work contents and work results, respectively, and store them in the blockchain node.

In particular, since there is a separate proof-of-work process for all participants to check the work content and work result drawn by a specific participant when storing in a block chain node, it fundamentally blocks problems with copyright disputes that may occur during the creation of works It is possible, and it is possible to properly settle and distribute copyright revenues after the work is completed.

In addition, in the case of an image work, there are many image samples, which are the results obtained in stages, and in the case of an image, the data capacity is generally large, so when parsing and storing it in the blockchain node, the storage requirement of the blockchain node is very large. To prevent this drawback, the hash value _{derived by applying the hash function to the hash value (OV H} ) is stored in the block chain node by applying the secret sharing of the present invention. This can reduce costs in terms of management and maintenance of blockchain data.

Hereinafter, a block chain-based image copyright management system and management method according to an embodiment of the present invention will be described with reference to the drawings.

1 is a diagram illustrating a block chain-based image copyright management system (hereinafter referred to as “system”) according to an embodiment of the present invention.

As shown in Figure 1, when the work result (WR) and the work result (Content result, CR) performed by the participant are uploaded to the block chain system through the participant terminal (M1), the block chain system performs the work content ( WR) and the work result (CR) are hashed _{to derive a hash value (OV H} ), and the work content (WR) and work result (CR) are encrypted by performing an encryption operation. (See Fig. 1A)

The system generates a hash fragment value (f(P _i )) using the hash value (OV _H ), distributes it to the participants, performs secret sharing, temporarily stores it in the blockchain node, and stores the encrypted work content ( WR) and work results (CR) are stored in the system's storage. (See Fig. 1B)

Participants perform proof of work by submitting the hash fragment value f(P _{i ) to the system through the participant terminal.} The system creates a blockchain node. (See Fig. 1 C)

As shown in FIG. 2 , the block chain-based image asset management method (hereinafter, also referred to as “image asset management method”) according to an embodiment of the present invention includes a hash value derivation step (S100), a pre-processing step (S200) , a secret sharing step (S300), a work proof step (S400), and a block chain storage step (S500). The above steps ( S100 to S500 ) may be performed by a computing device performing an arithmetic function, and the computing device will be described later with reference to FIG. 6 .

S100: Hash value derivation step

First, a specific participant uploads video work data including work details and work results for the work performed by him/her to the system. The system (computing device) receives the work content (WR) and work result (CR) written by a specific participant, and applies a hash function to the received image work data to derive _{a hash value (OV H ).} In this case, the hash function may use SHA (Secure Hash Algorithm)-3. The derived hash value OV _H may be "OV _H = h(WR||CR)".

Simultaneously with deriving the hash value (OV _H ), the system performs cryptographic operations on the work content (WR) and the work result (CR). That is, the actual original data (work contents (WR) and work result (CR)) are encrypted and stored in the storage, and _{a part of the hash value (OV H} ) of the original data is stored in the node. A technique used for encryption operation uses a symmetric key encryption such as AES (Advanced encryption standard) or a one-time password (OTP), but the secret key used for this may be applied differently depending on the system policy.

S200: pre-processing step

In this step, the number of participants (n) related to the image work data to be stored in the blockchain, the identifiers of the participants (P _i ~ P _n ), the irreducible polynomial (f(x)) in the finite field, and the proof of work Set a threshold value (t) for

Set the number (n) of participants participating in the production of video copyrighted data. And, for each participant, a participant's unique identifier (P _i ~ P _n ) is set. The identifiers P _i to P _n may be set to an arbitrary number.

Then, in the work proof step (S400) to be described later, the minimum number of participants required for work proof is set as the threshold value (t). For example, when the number of participants n is 10, the threshold value t may be set to 5. Alternatively, a particular participant may have a higher stake than another participant. That is, a general participant is counted as 1, while a specific participant may be counted as 2 or more.

Then, an arbitrary irreducible polynomial (f(x)) on a finite field is set.

A finite field is a field that has only a finite number of elements and forms an algebraic structure. It means a field in which the result of operation (addition, multiplication, etc.) of elements in a finite field set is again within the set.

An irreducible polynomial is a polynomial that cannot be factored any further. Depending on the finite field range, the reduced polynomial can be different. For example, if f(x) = x ² - 2 and g(x) = x ² + 2, if the finite body is a set of rational numbers, then f(x) and g(x) are irreducible polynomials because they are not factored. If the finite body is a set of real numbers, f(x) = x ² - 2 is factored into f(x) = (x - √2)(x + √2), so f(x) cannot be a reduced polynomial, g(x) becomes a reduced polynomial.

The reduced polynomial (f(x)) on the finite field set in this step is, for example, the following equation (1).

Formula (1):

Here, t is a threshold value, a _j is a coefficient value inserted as part of the hash value (OV _H) to be inserted in a block chain, the bit unit after parsing the binary hash value (OV _H). mod is a remainder function that finds the remainder of any division, and GF is a polynomial belonging to Galois feild. k means the number of bits, generally 8 or 16 is selected, and up to 64 can be selected depending on the amount of data to be stored in the block chain.

S300: Steps to perform secret sharing

In this step, the identifier (P _i ) is input into the reduced polynomial (f(x)) of Equation (1 _{) to generate a hash fragment value (f(P i} )), and the identifier (P _i ) and the corresponding hash Secret sharing is performed by distributing ordered pairs (P _i , f(P _i )) of the fragment values (f(P _i )) to the participants, respectively. Here, the meaning of “secret sharing” means that the hash fragment value f(P _i ) is distributed to several participants, respectively.

The identifier (Pi) performs a function similar to a kind of public key, and the hash fragment value (f(Pi)) performs a function similar to the private key (or private key). However, if the existing private key is exposed for various reasons, the corresponding block data may be hacked, but even if the hash fragment value f(Pi) of the present invention is exposed, since the secret is shared among the participants, Hacking is impossible and block data can be hacked only when t or more hash fragment values (f(P _i )) are exposed, but in the real world, hash fragment values (f(P _i )) are t threshold values. Since there is almost no case of abnormal exposure, the secret sharing method is superior in terms of safety compared to the existing public key or symmetric key.

As part of the formula of (1) coefficient of the polynomial a _j (j is 0 ~ t-1) is a hash value (OV _H) to insert into the physical block chain, and then parse the binary hash value (OV _H) , is inserted into the coefficient value a _{j in a certain unit.} The predetermined unit may be, for example, 8 bits or 16 bits, and may be the k size ^{of GF(2 k ) in Equation (1).} The sum of the coefficient values a _j can be a binary hash value (OV _H ).

The coefficient value a _j will be described with reference to FIG. 3 . 3 is a view for explaining a process of generating _{a coefficient value a j} of the irreducible polynomial (f(x)) _{from a hash value (OV H} ) in the step of performing secret sharing according to an embodiment of the present invention.

As shown in FIG. 3 , the hash value OV _H of the image work data is converted into binary data by the computing device of the present invention. The converted binary data is divided into a certain bit unit, and this is inserted as _{a coefficient value a j of the reduced polynomial (f(x)).} All the converted binary data is divided into a predetermined bit unit and inserted as _{a coefficient value a j of the reduced polynomial (f(x)).} Therefore, if all the coefficient values a _j are summed, the hash value OV _H may be binary data, and the hash value OV _H may be extracted by converting it again.

When the coefficient value a _j is determined from the binarized hash value (OV _H ), an identifier (P _i ) consisting of an arbitrary number is input into the irreducible polynomial (f(x)) of Equation (1) to enter the hash fragment value (f(P) _i )) can be created. Create and this hash slice value generated as (f (P _i)) to the input of identifiers (P _i) and the pair with ordered pairs _{_{(P i, f (P i}} )), the ordered pairs (P _i, f (P _i )) is distributed to the participants (participant terminals) of the corresponding identifier (P _{i ).} (See Fig. 4)

In Figure 4, the identifier (P _i ) is input into the irreducible polynomial (f(x)) in this secret sharing step, and an ordered pair (P _i , f( _{) of the identifier (P i} ) and the hash fragment value (f(P _{i ))} The _{process of distributing P i} )) to each participant is shown.

Finally, in this step, a hash fragment value (f(P _n+1 )) to be temporarily stored in the blockchain node is additionally generated. The hash fragment value (f(P _n+1 )) temporarily stored in the node is called the additional hash fragment value. The additional hash fragment value f(P _n+1 ) is generated by inputting the additional identifier P _n+1 into equation (1). The additional identifier (P _n+1 ) uses values such as nonce and time stamp within the block chain system and may be separately specified according to the operation policy of the block chain system.

The additional hash fragment value f(P _n+1 ) is stored in the node for proof-of-work in the proof-of-work step to be described later.

S400 :　Proof of work step

This step is a process of verifying data through proof-of-work of the additional hash fragment value (f(P _{n+1 )) temporarily stored in the blockchain node.} The proof-of-work step will be described with reference to FIG. 5 . 5 is a diagram for explaining a work proof step according to an embodiment of the present invention.

Proof-of-work to the n people threshold of the participants (t) over collusion submit their identifiers (P _i) and the hash fragment value (f (P _i)) ordered pair _{_{(P i, f (P i}} )) of the system and the system automatically initiates the proof-of-work process when more than the threshold t people are colluded.

The process of proof-of-work is the same as the restoration process of shared secret, and is performed using Lagrange interpolation. The interpolation method is a method of estimating the value of the interval using discrete data, and the Lagrange interpolation method is a method of creating an nth-order polynomial with (n+1) coordinates.

When t participants conspire and t ordered pairs (P _i , f(P _i )) are submitted to the system, the reduced polynomial f'(x) is derived through the following equation (2) using Lagrange interpolation. (See Fig. 5A)

Equation (2):

where x is the variable of the polynomial f'(x), x _o is the identifier (P _o ), x _j is the identifier (P _j ), y _j is the hash fragment value (f(P _j )), Π is a function that means product.

The additional hash fragment value (f'(P _n+1 )) _{by inputting the additional identifier (P n+1} ) stored in the node in step S300 into the reduced polynomial (f'(x)) derived through Equation (2) create Next, the newly created additional hash fragment value f'(P _n+1 ) is compared with the additional hash fragment value f(P _n+1 ) stored in the node, and if they are the same, the proof-of-work is terminated. (See Fig. 5B)

If the newly created additional hash fragment value (f'(P _n+1 )) and the additional hash fragment value stored in the node (f(P _n+1 )) are different, the value stored in the block chain by a malicious attacker Detects that the ordered pair (P _i , f(P _i )) of this altered or collusive participant is not correct.

When the proof-of-work is finished, binary data of the hash value (OV _H _{) is created by summing all the coefficient values a j} , and the hash value (OV _H ) can be extracted by converting it again. (See Fig. 5C)

S500: Blockchain storage stage

After the proof of work is completed, _{a hash value is generated using SHA-3 for the additional hash fragment value (f(P n+1} )) temporarily stored in the block chain, and it is stored in the block chain node. SHA-3 is a cryptographic hash function announced in August 2015 by the US National Institute of Standards and Technology to replace SHA-2.

In addition to the temporarily stored additional hash fragment value (f(P _n+1 )), the hash value of the node before the blockchain to create a block in the form of a chain, a nonce (or time stamp), and other blockchain systems to maintain the blockchain Designates various values that are policy-specified within the SHA-3 input. Through this, a new type of blockchain-based image asset management method using secret sharing is completed.

_{If the capacity (number of bits) of the binary data of the hash value (OV H} ) of the image work data to be stored in the block chain is large, the secret sharing execution step (S300) is performed with a coefficient value in one irreducible polynomial (f(x)) If it is not completed, another irreducible polynomial (g(x), h(x), ...) is additionally set, and the secret sharing is performed repeatedly until all transformed binary data are inserted as coefficient values (S300). ) is performed. _{In this case, step S300 is completed while additional hash fragment values (g(P n+1} ), h(P _n+1 ), ...) are stored in the node as many as the number of irreducible polynomials.

According to the block chain-based image asset management method according to an embodiment of the present invention as described above,

6 is a diagram illustrating a computing device according to an embodiment of the present invention. The computing device TN100 of FIG. 6 may be a computing device that performs operations S100 to S500 described above.

In the embodiment of FIG. 6 , the computing device TN100 may include at least one processor TN110 , a transceiver device TN120 , and a memory TN130 . In addition, the computing device TN100 may further include a storage device TN140 , an input interface device TN150 , an output interface device TN160 , and the like. Components included in the computing device TN100 may be connected by a bus TN170 to communicate with each other.

The processor TN110 may execute a program command stored in at least one of the memory TN130 and the storage device TN140. The processor TN110 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to an embodiment of the present invention are performed. The processor TN110 may be configured to implement procedures, functions, methods, and the like described in connection with an embodiment of the present invention. The processor TN110 may control each component of the computing device TN100 .

Each of the memory TN130 and the storage device TN140 may store various information related to the operation of the processor TN110 . Each of the memory TN130 and the storage device TN140 may be configured as at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory TN130 may include at least one of a read only memory (ROM) and a random access memory (RAM).

The transceiver TN120 may transmit or receive a wired signal or a wireless signal. The transceiver TN120 may be connected to a network to perform communication.

Meanwhile, the present invention may be implemented as a computer program. The present invention may be implemented as a computer program stored in a computer-readable recording medium in order to execute the block chain-based image copyright management method according to the present invention in combination with hardware.

The methods according to the embodiment of the present invention may be implemented in the form of a program readable by various computer means and recorded in a computer readable recording medium. Here, the recording medium may include a program command, a data file, a data structure, etc. alone or in combination.

The program instructions recorded on the recording medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software.

For example, the recording medium includes magnetic media such as hard disks, floppy disks and magnetic tapes, optical recording media such as CDROMs and DVDs, and magneto-optical media such as floppy disks. optical media), and hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like.

Examples of program instructions may include not only machine language such as generated by a compiler, but also a high-level language that can be executed by a computer using an interpreter or the like.

Such hardware devices may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

In the above, although an embodiment of the present invention has been described, those of ordinary skill in the art can add, change, delete or add components within the scope that does not depart from the spirit of the present invention described in the claims. The present invention may be variously modified and changed by, etc., and this will also be included within the scope of the present invention.

Claims

It is performed by a computing device and is a method of managing image assets based on a block chain consisting of a plurality of nodes,

Deriving a hash value (OV H ) by receiving the image work data including the work content and work result from the participant terminal, and applying a hash function to the received image work data;

Reducing polynomial (Finite Field) with the number of participants (n) related to the image work data to be stored in the block chain, the identifiers of the participants (P i , 1≤i≤n), and the identifiers of the participants as input values ( a preprocessing step of setting f(x));

By inputting the identifier (P i ) into the irreducible polynomial (f(x)), a hash fragment value (f(P i )) is generated, and the identifier (P i ) and hash fragment value (f(P i )) Distributing an ordered pair of (P i , f(P i )) to the participants, respectively, and an additional identifier (P n+1 ) and an additional hash fragment value (f(P n+1 )) other than the participants’ identifiers. A secret sharing step of storing the ordered pair (P n+1 , f(P n+1 )) in the node;

A blockchain-based video asset management method comprising a.
The method according to claim 1,

By inputting the ordered pair (P i , f(P i )) of the identifier (P i ) and the hash fragment value (f(P i )) into the equation using the Lagrange interpolation equation, the reduced polynomial (f'(x)) is derived. and,

The additional hash fragment value (f'(P n+1 )) generated by inputting the additional identifier (P n+1 ) into the derived irreducible polynomial (f'(x)) and the additional hash fragment value stored in the node ( A proof-of-work step that performs proof-of-work by comparing f(P n+1 ))

A blockchain-based video asset management method further comprising a.
The method according to claim 1,

The reduced polynomial (f(x)) is a block chain-based image asset management method defined by the following equation (1).

Formula (1):

(Where, t is a threshold value and, a j is the coefficient value inserted as part of the hash value (OV H) to be inserted in a block chain, the bit unit after parsing the binary hash value (OV H), mod is It is a remainder function that finds the remainder of an arbitrary division, GF is a polynomial belonging to Galois feild, and k means the number of bits)
4. The method according to claim 3,

When at least a part of the hash value (OV H ) to be inserted into the block chain is not inserted as a coefficient value (a j ) in the reduced polynomial (f(x)), another reduced polynomial (g(x), h(x) ), ...) to additionally set, repeating until all the transformed binary data of the hash value (OV H ) are inserted as coefficient values to perform the secret sharing step

A blockchain-based video asset management method.
3. The method according to claim 2,

The reduced polynomial (f'(x)) is a block chain-based image asset management method defined by the following equation (2).

Equation (2):

(where x is the variable of the polynomial f'(x), x o is the identifier (P o ), x j is the identifier (P j ), y j is the hash fragment value (f(P j )), Π is a function that means product)
The method according to claim 1,

The additional identifier (P n+1 ) is specified according to the operation policy of the block chain system using at least one of a nonce and a time stamp in the block chain system.

A blockchain-based video asset management method.
The method according to claim 1,

In the preprocessing step, a threshold value (t) for starting the proof-of-work step is set, and a threshold value (t) or more among n participants is collusive, so that their identifier (P i ) and hash fragment value (f(P i ) ) by submitting the ordered pair (P i , f(P i )) to the blockchain system to perform proof-of-work.

A blockchain-based video asset management method.
8. The method of claim 7,

The threshold value (t) is set to a higher stake than other participants for a specific participant.

A blockchain-based video asset management method.
coupled to the computing device;

Deriving a hash value (OV H ) by receiving the image work data including at least one of the work content and the work result from the participant terminal, and applying a hash function to the received image work data;

The number of participants (n) related to the video work data to be stored in the block chain, the identifiers of the participants (P i , 1≤i≤n), and the irreducible polynomial (f) in a finite field with the identifiers of the participants as input values (x)) a pre-processing step to set;

The identifier (P i ) is input into the reduced polynomial (f(x) ) to generate a hash fragment value (f(P i )), and the identifier (P i ) and hash fragment value (f(P i )) Distributing an ordered pair (P i , f(P i )) to the participants, respectively, and an additional identifier (P n+1 ) and an additional hash fragment value (f(P n+1 )) other than the participants’ identifiers. A secret sharing step of storing the ordered pair (P n+1 , f(P n+1 )) in the node;

By inputting the ordered pair (P i , f(P i )) of the identifier (P i ) and the hash fragment value (f(P i )) into the equation using the Lagrange interpolation equation, the reduced polynomial (f'(x)) is derived. and the additional hash fragment value (f'(P n+1 )) generated by inputting the additional identifier (P n+1 ) to the derived irreducible polynomial (f'(x)) and the additional hash fragment stored in the node A proof-of-work step that performs proof-of-work by comparing values f(P n+1 ).

A computer program stored in a computer-readable recording medium to execute the computer program.