Content generation device and content management device for registering information in block chain using audio data in video file, and control method and program therefor

Abstract

[Problem] To provide a content generation device capable of reducing the processing load of generating a hash value to be registered in a block chain in a configuration using audio data in a video file. [Solution] An imaging apparatus (102) generates a video file including video data, audio data, and metadata, and generates hash values from the audio data and the metadata. The image pickup apparatus (102) transmits the video file and the hash value to a management system (101) for registering the hash value and metadata in a blockchain.

Description

Technical Field

[0001] The present invention relates to a content generation device and a content management device for registering information in a blockchain using audio data in a video file, and a control method and program thereof. Background Art

[0002] In recent years, information dissemination via video distribution sites or audio media has become active, and the era has arrived where anyone can browse and transmit information. Under such circumstances, video file processing technology has further developed, making it more difficult for viewers of information to judge the authenticity of information. This has made problems such as fake news, fraud cases, etc. more serious. In order to solve these problems, a mechanism is increasingly needed to ensure the authenticity of video files (i.e., to ensure that no processing or forgery has been added to the video files).

[0003] As a mechanism to ensure the authenticity of video files, it is considered to use blockchain technology, which is widely used in finance and other industries. Using blockchain technology, it is possible to prevent the falsification of digital data in a decentralized manner and at low cost. For example, a management system using blockchain technology registers the hash value of the content together with the metadata associated with the content in the blockchain to ensure the authenticity of the content from the time the content is generated (for example, refer to patent document 1). This technology makes it possible to obtain content from the management system that has not been processed or otherwise tampered with since the content was generated, and publish the obtained content on the Internet, SNS, etc.

[0004] Citation List

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-204706 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] In recent years, it is not the video file itself that registers various types of information in the blockchain, but the audio data in the video file that is increasingly used. On the other hand, the video file has a larger data volume than other content such as a still image file, and the generation of the hash value of the video file has a larger processing load than the generation of the hash value of the other content. Therefore, in the above-mentioned form of use, a mechanism capable of reducing the processing load of generating the hash value to be registered in the blockchain is required.

[0009] The present invention provides a content generating device and a content managing device capable of reducing a processing load for generating a hash value to be registered in a blockchain in a configuration using audio data in a video file, and a control method and program thereof.

[0010] Solutions for solving problems

[0011] In order to solve the above-mentioned problem, the content generating device according to the present invention includes: a component for generating a video file including video data, audio data and metadata; a component for generating a hash value from the audio data and the metadata; and a transmitting component for transmitting the hash value and the video file to a content management device for registering the hash value and the metadata in a block of a blockchain.

[0012] Advantageous Effects of the Invention

[0013] According to the present invention, in a configuration using audio data in a video file, the processing load of generating a hash value to be registered in a blockchain can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a diagram for explaining the function of a management system as a content management device that communicates with an imaging device as a content generation device according to the present embodiment.

[0015] Figure 2 It is schematically shown Figure 1 A block diagram of the configuration of the camera device in FIG.

[0016] Figure 3 It is shown in Figure 1 Flowchart of steps of data transmission processing performed in a camera device.

[0017] Figure 4 It is schematically shown Figure 1 Block diagram of the configuration of the management system in .

[0018] Figure 5 It is shown Figure 4 FIG. 1 is a diagram of an example configuration of an image database.

[0019] Figure 6 It is shown in Figure 1 Flowchart of the steps of blockchain registration processing performed in a management system.

[0020] Figure 7 It is shown by Figure 4 A diagram of an example of a block data structure of a blockchain managed by a blockchain management unit in .

[0021] Figure 8 It is shown in Figure 1 Flowchart of the steps of authenticity judgment processing performed in the management system. DETAILED DESCRIPTION

[0022] Embodiments of the present invention will be described below. It should be noted that the embodiments of the present invention are not limited to the following description.

[0023] Figure 1 1 is a diagram for explaining the function of a management system 101 as a content management device that communicates with an imaging device 102 as a content generation device according to the present embodiment.

[0024] The management system 101 has a function of managing content acquired from an external device such as a camera device 102 via the Internet or the like. The management system 101 is implemented by one or more computer devices. It should be noted that in the present embodiment, a configuration in which the management system 101 also communicates with and uses the blockchain peer-to-peer network 104 will be described, but the present invention is not limited to this configuration and can be implemented using other networks.

[0025] like Figure 1 As shown, when shooting a video, the camera 102 generates a video file including video data, audio data, and metadata to be described later. Subsequently, the camera 102 generates an audio file including audio data and metadata in the video file. Subsequently, the camera 102 performs a hash function on the generated audio file to generate a hash value of the audio file. Since the audio file does not include video data, the data volume of the audio file is much smaller than the data volume of the video file. Therefore, compared with the case where the hash value is generated from the video file, the generation of the hash value from the audio file reduces the processing load of generating the hash value. In particular, it is highly desirable to reduce the processing load of generating hash values ​​in devices (such as camera devices, etc.) with lower computing performance than personal computers. It should be noted that the metadata includes attribute information of the image data indicating the shooter of the image data, the shooting time, the shooting location, the model of the camera device, the setting value when shooting, etc., and the data volume of the metadata is smaller than the data volume of the video data.

[0026] In addition, in the present embodiment, the camera device 102 performs trimming processing on the audio data included in the generated video file, and performs a hash function on the trimmed audio data and metadata. The portion removed from the audio data by the trimming process (the portion to be trimmed) is, for example, unnecessary information such as silence or noise that lasts for a specific period of time. The conditions for determining such a portion to be trimmed can be pre-set for the camera device 102 by the photographer or the like. By performing trimming processing on the audio data, the amount of audio data can be made smaller than the amount of data before the trimming process is performed, and the processing load for generating the hash value can be further reduced.

[0027] The camera device 102 transmits the video file, the hash value (audio hash value), and the hash value calculation details in association with each other to the management system 101 (step (1)). The camera device 102 may also transmit the audio file in step (1). The audio file does not include video data, but can be widely used as audio content. Similar to the video file, the authenticity of the audio file can also be guaranteed by registering the hash value in the blockchain.

[0028] The hash value calculation details are information describing data (in this embodiment, audio data and metadata included in an audio file) on which a hash function is performed in the data included in the video file. It should be noted that the hash function may not be performed on all items of the metadata, and the hash function may be performed on some items of the metadata. When the hash function is performed on some items of the metadata, the hash value calculation details indicate which item of the metadata the hash function is performed on. In addition, when trimming processing is performed on audio data, the hash value calculation details may describe information indicating conditions for determining a portion to be trimmed.

[0029] It should be noted that for the algorithm of the hash function, only the default algorithm can be used, or one of the multiple algorithms such as SHA256 and MD5 can be selected. In the case of a configuration in which one of the multiple algorithms can be selected, the algorithm used for hash value calculation is also described in the hash value calculation details. When hashing, for example, audio data, the algorithm SHA 256 processes the data in units of 64 bytes from the head to the tail of the data, thereby generating a 32-byte (256-bit) hash value. If the entire audio data is repeatedly processed from the head of the audio data The first 64 bytes are used for processing and the next 64 bytes are skipped and not used for processing, the processing amount will be halved. The hash value calculation details in this case can be expressed as "algorithm, SHA 256, read, 64, skip, 64" in a CSV file format, for example. It should be noted that the format of the hash value calculation details is not limited to the CSV file format. For the hash value calculation details, a widely used file format such as the JSON file format can be used, or a unique file format can be used.

[0030] Note that in this embodiment, description will be given about a configuration in which the camera 102 generates a hash value and transmits the hash value to the management system 101, but the present invention is not limited to this configuration. For example, the management system 101 may generate a hash value based on an audio file acquired from the camera 102.

[0031] Upon receiving the video file, hash value, and hash value calculation detailed information from the camera 102, the management system 101 of this embodiment generates an authenticity assurance number as a unique number in the management system 101. The authenticity assurance number is an identification number for uniquely identifying a video file.

[0032] The management system 101 generates transaction data including video file information such as metadata, hash value, hash value calculation details, and authenticity guarantee number, and connects the block written with the generated transaction data to the blockchain. Specifically, the management system 101 publishes the generated transaction data and broadcasts the transaction data to one or more computers (nodes) participating in the blockchain peer-to-peer network 104 (step (2)). By doing so, the transaction data is temporarily stored in the transaction pool, and when the transaction data is approved by the miner, the verification is completed. Then, a block of transaction data is generated, and the generated block is added to the tail of the blockchain. As a result, the video file information is registered in the blockchain.

[0033] After the block in which the transaction data is written is connected to the blockchain in step (2), the management system 101 stores (provides) the video file and the authenticity guarantee number in association with each other in a later-described Figure 4 The management system 101 then transmits a registration completion notification indicating completion of the process of registering the video file information in the blockchain to the camera device 102 (step (3)).

[0034] Thereafter, the management system 101 enables the user (e.g., the photographer or the image provider) to select a video file to be published on the image publishing website 103 from a plurality of video files registered in the image database 407 (step (4)). Specifically, the user is allowed to access the web page of the management system 101 from the communication device 105a operated by the user, and select the video file to be published on the image publishing website 103 on the web page. The management system 101 provides the video file selected by the user and the authenticity guarantee number associated with the selected video file to the image publishing website 103 (step (5)). At the same time, the management system 101 notifies the communication device 105a that the video file selected by the user in step (4) is now ready to be published on the image publishing website 103.

[0035] The display of the image publishing website 103 is controlled so that the authenticity assurance number provided together with the video file from the management system 101 is displayed near the video file on the web page, for example. It should be noted that the display position of the authenticity assurance number is not limited to this, and the authenticity assurance number can be displayed at any position where a viewer of the image publishing website 103 can recognize that the authenticity assurance number corresponds to the video file.

[0036] A viewer of the image publishing website 103 may want to confirm that the video file displayed on the web page of the image publishing website 103 has not been tampered with since the time of shooting. In this case, the viewer first uses the communication device 105b to obtain (download) the video file and the authenticity guarantee number associated with the video file from the image publishing website 103 (step (6)). Specifically, the viewer accesses the web page of the image publishing website 103 from the communication device 105b, selects the video file published on the web page, and instructs the download. When receiving the instruction, the image publishing website 103 transmits the video file selected by the viewer and the authenticity guarantee number associated with the selected video file to the communication device 105b.

[0037] When the download is completed in step (6), the communication device 105b (first communication device) transmits the authenticity confirmation request of the video file together with the acquired video file and the authenticity guarantee number to the management system 101 (step (7)). In the present embodiment, the authenticity confirmation request is made by the viewer using the communication device 105b, attaching the video file and the authenticity guarantee number acquired from the image publishing website 103 to an input form provided by the management system 101. However, the authenticity confirmation request is not limited to the method of the present embodiment, and for example, the authenticity confirmation request may be made by transmitting an email to which the video file and the authenticity guarantee number are attached to the management system 101.

[0038] When receiving the authenticity confirmation request from the communication device 105b, the management system 101 determines the authenticity of the video file that is the object of the authenticity confirmation request. It should be noted that here, the timing for determining the authenticity is when the management system 101 receives the authenticity confirmation request for the image data displayed on the image publishing website 103 from the communication device 105b of the viewer of the image publishing website 103, but is not limited to this. For example, the management system 101 can periodically determine the authenticity based on the image database 407. The management system 101 displays the authenticity determination result on the web page of the management system 101, or notifies the communication device 105b of the authenticity determination result by e-mail (step (8)).

[0039] Figure 2 It is schematically shown Figure 1 1 is a block diagram of a configuration of an imaging apparatus 102. The imaging apparatus 102 is a camera such as a digital camera or a digital video camera, or an electronic device having a video capturing function such as a mobile phone having a camera function or a camera-equipped computer.

[0040] refer to Figure 2The camera device 102 includes an MPU 201, a timing signal generating circuit 202, an image sensor 203, an A / D converter 204, a memory controller 205, a buffer memory 206, a video output unit 207, a storage medium I / F 208, a storage medium 209, a hash value generating unit 210, a communication unit 211, an audio processing unit 212, and a video generating unit 213.

[0041] The MPU 201 is a microcontroller for performing control related to the system of the image pickup device 102, such as a shooting sequence. The timing signal generation circuit 202 generates timing signals required for operating the image pickup element 203 and the audio processing unit 212. The image pickup element 203 is an image sensor such as a CCD or a CMOS that receives light reflected from a subject and converts the reflected light into an electrical signal. The A / D converter 204 converts analog video data read from the image pickup element 203 into digital video data.

[0042] The memory controller 205 controls reading from and writing to the memory, refreshing of the buffer memory 206, and the like. The buffer memory 206 stores the video file generated by the video generation unit 213, and the like. The video output unit 207 displays the video data included in the video file stored in the buffer memory 206 through a monitor (not shown) of the camera 102, and the like, and outputs the audio data through a speaker (not shown) of the camera 102, and the like. The storage medium I / F 208 is an interface for controlling reading and writing of data from and to the storage medium 209. The storage medium 209 is a memory card or a hard disk, and the like, and stores programs, audio files, video files, and the like.

[0043] The hash value generation unit 210 performs a hash function on the audio file including the trimmed audio data and metadata to generate a hash value of the audio file. It should be noted that the hash value generation unit 210 can generate a hash value by performing a hash function on the audio data instead of the audio file. In addition, in the present embodiment, the MPU 201 can generate a hash value instead of the hash value generation unit 210. The communication unit 211 is connected to the Internet and transmits and receives data to and from an external device.

[0044] The audio processing unit 212 performs audio processing for converting the sound collected by the sound collecting unit (not shown) such as a microphone of the camera 102 and the ambient sound into an electrical signal, and generates analog audio data. The generated analog audio data is converted into digital audio data by the A / D converter 204. In addition, the audio processing unit 212 can also perform the above-mentioned trimming processing on the digital audio data to generate audio data from which the portion to be trimmed has been removed. The video generation unit 213 generates a video file by synchronizing the audio data and the video data based on a time code or the like.

[0045] Figure 3 It is shown Figure 1 Flowchart of steps of data transfer processing performed in the camera 102 in FIG. Figure 3 The data transmission processing of is realized by the MPU 201 of the camera 102 executing a program stored in the storage medium 209 or the like. When the camera 102 receives a predetermined video shooting start operation performed by the photographer, such as performing an audio file hash value output setting and then pressing a video shooting button of the camera 102, the video shooting start operation is realized. Figure 3 The audio file hash value output setting is a setting for generating a hash value of an audio file including audio data and metadata included in a video file.

[0046] exist Figure 3 In the process, the MPU 201 drives a shutter (not shown) to control the exposure time (step S301). Subsequently, the MPU 201 performs an image pickup process in which the image pickup element 203 receives light reflected from the subject and converts the reflected light into an electrical signal (step S302). Subsequently, the MPU 201 performs image processing such as development and encoding on the data obtained by the image pickup process of step S302 (step S303). In this way, video data is generated. Thereafter, the process proceeds to step S305.

[0047] In addition, in parallel with step S302, the MPU 201 controls the audio processing unit 212 to perform audio processing for converting the audio and environmental sound collected by the sound collection unit (such as a microphone, etc.) of the camera 102 into electrical signals (step S304). The analog audio data generated by the audio processing is converted into digital audio data by the A / D converter 204. Subsequently, the MPU 201 determines whether an instruction to perform trimming processing is received from the memory controller 205, etc. (step S305). If the MPU 201 determines in step S305 that an instruction to perform trimming processing is not received from the memory controller 205, etc., the processing proceeds to step S307 to be described later. If the MPU 201 determines in step S305 that an instruction to perform trimming processing is received from the memory controller 205, etc., the processing proceeds to step S306 to be described later. It should be noted that in the present embodiment, the photographer, etc. is allowed to set in advance whether to perform trimming processing for the camera 102, and the MPU 201 can control whether to perform trimming processing based on the setting.

[0048] In step S306, the MPU 201 controls the audio processing unit 212 to perform a trimming process. In the trimming process, the MPU 201 determines whether the digital audio data obtained by the conversion of the A / D converter 204 includes a portion to be trimmed (for example, unnecessary information such as silence or noise that lasts for a certain period of time). When it is determined that the portion to be trimmed is included in the digital audio data, the audio processing unit 212 removes the portion to be trimmed from the digital audio data to generate "trimmed audio data". In addition, in the case of generating the trimmed audio data, the audio processing unit 212 removes data having the same time code as the portion to be trimmed of the audio data in the video data to generate the trimmed video data.

[0049] Subsequently, the MPU 201 generates metadata (step S307). The metadata includes attribute information of the content. The attribute information of the content is, for example, information indicating the photographer, shooting time, shooting location, model of the camera equipment, setting values ​​at the time of shooting, time code of the part to be trimmed, etc. It should be noted that the information included in the metadata is not limited to the above information, and any information that can be set by the photographer can be further included in the metadata. For example, when the photographer is shooting a live music performance, etc., information related to the artist's name or information related to the music can be included in the metadata. In addition, when the photographer performs audio distribution, etc., the photographer's name and SNS account, etc. can be included in the metadata. It should be noted that if the MPU 201 determines in step S305 that no instruction to perform trimming processing has been received from the memory controller 205, etc., the processing of step S307 is also performed.

[0050] Subsequently, the MPU 201 controls the video generation unit 213 to generate a video file (step S308). Specifically, the MPU 201 controls the video generation unit 213 to generate video data by synchronizing the audio data and the video data with a time code, etc., and generates a video file in an MPEG format or the like including the generated video data and metadata. In addition, the MPU 201 generates an audio file in an MP3 format or the like including the trimmed audio data and metadata.

[0051] Subsequently, the MPU 201 performs a hash function on the generated audio file to generate a hash value of the audio file (step S309). Subsequently, the MPU 201 transmits the hash value of the audio file generated in step S309 and the video file generated in step S308 to the management system 101 (step S310). It should be noted that the data transmitted in step S310 may have been encrypted. Subsequently, the MPU 201 stores the video file generated in step S308 in the storage medium 209 (step S311), and ends the present process.

[0052] As described above, in this embodiment, when the audio file hash value output setting is performed and the camera 102 captures a video, not only is the video file recorded in the storage medium 209 , but also the hash value of the audio file and the video file are transmitted to the management system 101 .

[0053] Figure 4 It is schematically shown Figure 1 1 is a block diagram of a configuration of a management system 101 in FIG. The management system 101 includes one or more computers connected to a network.

[0054] refer to Figure 4 The management system 101 includes a control unit 400, a data receiving unit 401, a data transmission unit 402, an authenticity guarantee number generation unit 403, and a transaction generation unit 404. The management system 101 also includes a block generation unit 405, a blockchain management unit 406, an image database 407, a hash generation unit 408, and a hash comparison unit 409.

[0055] The control unit 400 controls the entire management system 101 .

[0056] The data receiving unit 401 receives various data from an external device. For example, the data receiving unit 401 receives a hash value of an audio file, hash value calculation detailed information, and a video file from the camera 102. In addition, the data receiving unit 401 receives a video file and an authenticity guarantee number that are the object of authenticity judgment from the communication device 105b operated by a viewer of the image publishing site 103.

[0057] The data transmission unit 402 transmits various data to an external device. For example, the data transmission unit 402 transmits the video file selected to be published on the image publishing website 103 and the authenticity guarantee number corresponding thereto to the communication device 105a operated by the user (e.g., the photographer or the image provider). In addition, the data transmission unit 402 transmits the authenticity judgment result to the communication device 105b operated by the viewer who has made an authenticity confirmation request for the video file.

[0058] Upon receiving the hash value and the video file from the camera 102 , the authenticity assurance number generation unit 403 generates an authenticity assurance number which is a unique number in the management system 101 .

[0059] The transaction generation unit 404 generates transaction data and broadcasts the generated transaction data to one or more computers (nodes) participating in the blockchain peer-to-peer network 104. The transaction data includes a hash value received from the camera device 102, an authenticity guarantee number generated when the hash value is received and associated with the video file, and metadata included in the video file. It should be noted that the transaction data may also include an audio file.

[0060] When the miner approves the broadcasted transaction data and completes its verification, the block generation unit 405 generates a block in which the transaction data is written and connects the block to the blockchain.

[0061] The blockchain management unit 406 manages the blockchain also maintained by one or more computers (nodes) participating in the blockchain peer-to-peer network 104. The management system 101 and the nodes are synchronized with each other so that the blockchains they maintain always have the same content.

[0062] In the image database 407, the video file and the authenticity guarantee number corresponding to the video file are registered. Figure 5 As shown, the image database 407 includes a block ID 501, an authenticity guarantee number 502, and a video file name 503 which are associated with each other.

[0063] In block ID 501, a block ID (ID number) is set, which is issued sequentially each time a block in which a video file is written is connected to the blockchain. That is, each block ID set in block ID 501 corresponds to one of the hash values ​​registered in the blockchain.

[0064] The authenticity assurance number corresponding to the video file is set as the authenticity assurance number 502 .

[0065] The file name of the video file received by the management system 101 from the imaging apparatus 102 or the like is set in the video file name 503 .

[0066] It should be noted that the configuration of the image database 407 is not limited to the above-described configuration, and the image database 407 may include other items.

[0067] Refer again Figure 4 When judging the authenticity, the hash generation unit 408 obtains audio data and metadata from the video file transmitted by the communication device 105b of the user (viewer) who has made an authenticity confirmation request, generates an audio file, and generates a hash value by performing a hash function on the generated audio file.

[0068] The hash comparison unit 409 obtains a block (described later) corresponding to the authenticity guarantee number transmitted from the user who has made an authenticity confirmation request from the blockchain managed by the blockchain management unit 406. Then, the hash comparison unit 409 obtains the hash value (audio hash value) written in the obtained block. The hash comparison unit 409 compares the hash value obtained from the block with the hash value generated by the hash generation unit 408 to judge the authenticity. When the hash value obtained from the block is the same as the hash value generated by the hash generation unit 408, the hash comparison unit 409 determines that the video file transmitted from the user who has made the authenticity confirmation request has not been tampered with since the generation (true). On the other hand, when the hash value obtained from the block and the hash value generated by the hash generation unit 408 are different from each other, the hash comparison unit 409 determines that the video file transmitted from the user who has made the authenticity confirmation request has been tampered with since the generation (not true and false).

[0069] For example, when a video file distributed from the image publishing website 103 to the communication device 105b has been tampered with, the tampered video file is transmitted to the management system 101 together with the authenticity confirmation request. When the video file has been tampered with since it was generated, the hash value generated by the hash generation unit 408 performing a hash function on the audio file generated from the video file is different from the hash value calculated for the audio file generated from the video file before the tampering. In addition, the hash value stored in the blockchain by the management system 101 cannot be changed by anyone. Therefore, when an authenticity confirmation request is made for the tampered video file, the hash value generated by the hash generation unit 408 for the audio file generated from the video file is inconsistent with the hash value stored in the block corresponding to the authenticity assurance number of the authenticity confirmation request in the blockchain.

[0070] On the other hand, when the video file has not been edited or tampered with, the audio file generated from the video file by the hash generation unit 408 does not change. Therefore, when the video file has not been edited or tampered with since it was generated, the hash value generated by the hash generation unit 408 for the audio file generated from the video file is consistent with the hash value stored in the block corresponding to the authenticity guarantee number of the authenticity confirmation request in the blockchain.

[0071] As described above, in the present embodiment, the hash values ​​of the video file and the audio file transmitted from the camera 102 are managed in association with each other by the management system 101. Therefore, the audio file and the video file corresponding to the hash value can be easily provided. It should be noted that the image database 407 can also include the file name of the audio file corresponding to the video file as an item.

[0072] Figure 6 It is shown in Figure 1 Flowchart of the steps of blockchain registration processing performed in the management system 101. Figure 6 The blockchain registration process is implemented by the control unit 400 executing a program stored in a storage medium included in a computer constituting the management system 101. For example, when the camera 102 performs Figure 3 When the data transmission process is performed and the hash value and the video file are transmitted from the camera device 102, Figure 6 Blockchain registration processing.

[0073] exist Figure 6 In the embodiment of the present invention, the control unit 400 receives a hash value of an audio file, hash value calculation details, and a video file from the camera 102 (step S601). In the case where the received data has been encrypted, the control unit 400 performs a decryption process on the received data. Thereafter, the control unit 400 stores video file information such as the hash value, hash value calculation details, audio data and metadata included in the received video file in a RAM (not shown).

[0074] Then, the control unit 400 generates an audio file based on the audio data and metadata extracted from the received video file. Then, the control unit 400 applies a hash function to the audio file (performs a hash function on the audio file) to calculate (generate) a hash value (step S602). Then, the control unit 400 determines whether the hash value of the audio file received in step S601 is consistent with the hash value calculated in step S602 (step S603).

[0075] As a result of the determination in step S603, if the hash value of the received audio file is consistent with the calculated hash value, the process proceeds to step S604 to be described later. As a result of the determination in step S603, if the hash value of the received audio file is inconsistent with the calculated hash value, the process proceeds to step S609. In step S609, the control unit 400 issues an error notification indicating that the information and data received from the camera 102 in step S601 cannot be registered in the blockchain. Thereafter, the present process ends.

[0076] In step S604, the control unit 400 controls the authenticity assurance number generation unit 403 to generate an authenticity assurance number for the received video file.

[0077] Subsequently, the control unit 400 registers the video file information such as the hash value, hash value calculation details, and metadata stored in the RAM in step S601 in the blockchain (step S605). Specifically, first, the control unit 400 causes the transaction generation unit 404 to generate transaction data including the hash value, hash value calculation details, and metadata. Subsequently, the control unit 400 causes the transaction generation unit 404 to broadcast the transaction data to one or more computers (nodes) participating in the blockchain peer-to-peer network 104. When the broadcasted transaction data is approved by the miner and its verification is completed, the block generation unit 405 generates a block in which the verified transaction data is written, and connects (registers) the generated block to the blockchain.

[0078] Subsequently, the control unit 400 issues a block ID corresponding to the generated block (step S606). Here, the control unit 400 issues a value generated by performing a hash function twice on the header of the block as the block ID. It should be noted that the block ID is used to refer to the block, but there is no field for the block ID in the block.

[0079] Subsequently, the control unit 400 registers the issued block ID, the video file received in step S601, and the authenticity assurance number generated in step S604 in association with each other in the image database 407 (step S607). The control unit 400 may also generate an audio file from the audio data and metadata included in the video file, and register the audio file in the image database 407 in association with the authenticity assurance number shared with the video file. Subsequently, the control unit 400 transmits a registration completion notification indicating that the process of registering the video file information in the blockchain is completed to the camera device 102 (step S608). Thereafter, the blockchain registration process ends.

[0080] Figure 7 It is shown by Figure 4 FIG. 4 is a diagram of an example of a block data structure of a blockchain managed by the blockchain management unit 406 in FIG. Figure 7 As shown, a blockchain is a database formed by connecting blocks like a chain along a time series. A block 701 connected to the blockchain includes a hash 702 of a previous block, a random number 703, and a transaction 704.

[0081] The hash of the previous block 702 is a hash value in a block connected to the blockchain one block before the block 701. The random number 703 is a random number value used for mining (verification and approval). The transaction 704 is transaction data generated by the transaction generation unit 404. The transaction 704 includes information indicating the transaction type, a hash value of the audio file received from the camera 102 (in Figure 7 , it is described as an "audio hash") along with metadata included in the video file.

[0082] According to the above embodiment, a hash value of an audio file is generated from an audio file including audio data and metadata included in a video file, and the hash value of the audio file and the video file are transmitted to the management system 101. That is, in the case where the processing load for generating the hash value is smaller than that for the video file, the hash function is not performed on the video file but on the audio file. Therefore, in a configuration using audio data in a video file, the processing load for generating a hash value to be registered in the blockchain can be reduced.

[0083] In addition, in the above-described embodiment, the camera 102 is a device that captures a subject to generate a video file. Therefore, in the camera 102 that captures a subject to generate a video file, the processing load for generating a hash value to be registered in the blockchain can be reduced.

[0084] It should be noted that in the present embodiment, a configuration has been described in which the camera 102 transmits the hash value of the audio file to the management system 101 together with the video file, but the present invention is not limited to this configuration. For example, the camera 102 may transmit the hash value of the audio file and the audio file to the management system 101. The management system 101 performs the above-mentioned blockchain registration processing based on the received audio file and the hash value of the audio file, and registers the audio file in the image database 407 in association with the hash value of the audio file registered in the blockchain. Therefore, the audio file corresponding to the hash value can be easily provided.

[0085] In addition, in the present embodiment, the camera 102 may transmit the hash value of the audio file together with the video file and the audio file to the management system 101. The management system 101 performs the above-mentioned blockchain registration process based on the hash values ​​of the received audio file, video file, and audio file. Through the blockchain registration process, the video file and the audio file are registered in the image database 407 in association with the hash value of the audio file registered in the blockchain. Therefore, an audio file corresponding to the hash value and a video file obtained by adding video data to the audio file can be easily provided.

[0086] In the present embodiment, a configuration is described in which the camera device 102 generates a hash value of an audio file and transmits the hash value to the management system 101, but the present invention is not limited to this configuration. For example, the management system 101 may acquire an audio file from the camera device 102, and perform a hash function on the acquired audio file to generate a hash value of the audio file. Alternatively, the management system 101 may acquire a video file from the camera device 102, and perform a hash function on the audio file including the audio data and metadata included in the acquired video file to generate a hash value of the audio file. With this configuration, the same effect as the above-described embodiment can also be obtained.

[0087] Furthermore, in the configuration of the present embodiment, the camera 102 performs trimming processing on the audio data, however, the present invention is not limited to this configuration, and the management system 101 may perform trimming processing on the audio data.

[0088] Figure 8 It is shown in Figure 1 Flowchart of the steps of the authenticity judgment process performed in the management system 101. Figure 8 The authenticity judgment processing is implemented by the control unit 400 executing a program stored in a storage medium included in a computer constituting the management system 101. It should be noted that when using Figure 8 In the description, when a viewer of the image publishing website 103 operates the communication device 105b and thus the communication device 105b makes an authenticity confirmation request for the video file displayed on the image publishing website 103 to the management system 101, the authenticity judgment processing is executed. However, the start of the authenticity judgment processing is not limited to this.

[0089] exist Figure 8 In the embodiment, the control unit 400 receives an authenticity confirmation request from the communication device 105b operated by the viewer through the data receiving unit 401 (step S801). At the time of receiving, the control unit 400 also receives the video file as the object of authenticity judgment and the authenticity guarantee number corresponding to the video file through the data receiving unit 401.

[0090] Subsequently, the control unit 400 makes an inquiry to the image database 407 using the authenticity assurance number received in step S801 as a key, and acquires a block ID corresponding to the authenticity assurance number (step S802).

[0091] Subsequently, the control unit 400 accesses the block corresponding to the acquired block ID in the blockchain, and acquires the hash value (audio hash) stored in the block (step S803).

[0092] In addition, in parallel with the processing of steps S802 and S803, the control unit 400 causes the hash generation unit 408 to perform a hash function on the audio file including the audio data and metadata included in the video file received in step S801 (step S804). Therefore, the control unit 400 causes the hash generation unit 408 to generate (acquire) a hash value. Specifically, the control unit 400 accesses a block corresponding to the acquired block ID among the multiple blocks constituting the blockchain, and acquires the hash value calculation detailed information stored in the block. In step S804, a hash value is generated with reference to the hash value calculation detailed information.

[0093] When the processing of steps S802 to S804 is completed, the control unit 400 causes the hash comparison unit 409 to compare the audio hash acquired in step S803 with the hash value generated in step S804 (step S805 ).

[0094] The control unit 400 determines whether the two hash values ​​compared in step S805 match each other (step S806 ).

[0095] As a result of the determination in step S806, if the two hash values ​​match, the control unit 400 determines that the video file received in step S801 is "true" indicating that the video file has not been tampered with since it was generated (step S807). Thereafter, the process proceeds to step S809.

[0096] On the other hand, as a result of the determination in step S806, if the two hash values ​​do not match, the control unit 400 determines that the video file received in step S801 is "fake" indicating that the video file has been tampered with since it was generated (step S808). Thereafter, the process proceeds to step S809.

[0097] Subsequently, the control unit 400 controls the block generation unit 405 to register the judgment result of step S807 or step S808 in the blockchain (step S809). Specifically, the block generation unit 405 generates a block in which the judgment result of step S807 or S808 is written, and connects the generated block to the blockchain.

[0098] Subsequently, the control unit 400 controls the data transmission unit 402 to notify the communication device 105b, which is the request source of the authenticity confirmation request, of the determination result (step S810), and ends the present process.

[0099] The present invention can also be implemented by supplying a program for implementing one or more functions of the above-mentioned embodiments to a system or device via a network or storage medium and one or more processors in a computer of the system or device read and execute the processing of the program. In addition, the present invention can also be implemented by a circuit (e.g., ASIC) that implements one or more functions.

[0100] Reference numerals list

[0101] 101 Management System

[0102] 102 Camera Equipment

[0103] 201MPU

[0104] 210 Hash value generation unit

[0105] 211 Communication Unit

[0106] 212 Audio Processing Unit

[0107] 213 Video Generation Unit

[0108] 400 control unit

[0109] 401 Data Receiving Unit

[0110] 404 transaction generation unit

[0111] 405 Block Generation Unit

[0112] 406 Blockchain Management Unit

[0113] 407 Image Database

Claims

1. A content generating device, comprising: A component for generating a video file including video data, audio data and metadata; means for generating a hash value from said audio data and said metadata; as well as A transmitting means for transmitting the hash value and the video file to a content management device for registering the hash value and the metadata in a block of a blockchain.

2. The content generating device according to claim 1, wherein: managing the video file in association with the chunk ID and the authenticity guarantee number of the chunk, and The video file is provided together with the authenticity guarantee number.

3. The content generating device according to claim 1, wherein: The transmitting component also transmits the audio file including the audio data and the metadata to the content management device, and The audio file is managed by the content management device in association with the authenticity guarantee number shared with the video file.

4. The content generating device according to claim 1, further comprising a component for performing a trimming process for removing silence or noise lasting for a specific period of time from the audio data, wherein: A hash value is generated from the metadata and the trimmed audio data.

5. The content generating device according to claim 1, wherein: The content generating device is a camera device that captures a subject to generate a video file.

6. A content management device, comprising: A component for obtaining a video file including video data, audio data and metadata and a hash value; means for generating a hash value from said audio data and said metadata; A component for registering an identifier for uniquely identifying the video file and the hash value in a block of the blockchain when the acquired hash value and the generated hash value are consistent; as well as Means for distributing an audio file including the audio data to other devices in association with the identifier.

7. The content management device according to claim 6, further comprising means for managing the video file in association with the chunk ID and the authenticity guarantee number of the chunk.

8. The content management device according to claim 7, wherein: The identifier is an authenticity guarantee number.

9. The content management device according to claim 6, further comprising a component for performing a trimming process for removing silence or noise lasting for a specific period of time from the audio data, wherein: A hash value is generated from the metadata and the trimmed audio data.

10. The content management device according to claim 6, wherein: The video file and the hash value are acquired from a camera device.

11. A method for controlling a content generating device, the method comprising: The step of generating a video file including video data, audio data and metadata; The step of generating a hash value from said audio data and said metadata; as well as The step of transmitting the hash value and the video file to a content management device for registering the hash value and the metadata in a block of a blockchain.

12. A method for controlling a content management device, the method comprising: The step of obtaining a video file including video data, audio data and metadata and a hash value; The step of generating a hash value from said audio data and said metadata; When the acquired hash value and the generated hash value are consistent, registering an identifier for uniquely identifying the video file and the hash value in a block of the blockchain; as well as The step of distributing an audio file including the audio data to other devices in association with the identifier.

13. A program for causing a computer to execute a method for controlling a content generating device, the method comprising: The step of generating a video file including video data, audio data and metadata; The step of generating a hash value from said audio data and said metadata; as well as The step of transmitting the hash value and the video file to a content management device for registering the hash value and the metadata in a block of a blockchain.

14. A program for causing a computer to execute a method for controlling a content management device, the method comprising: The step of obtaining a video file including video data, audio data and metadata and a hash value; The step of generating a hash value from said audio data and said metadata; When the acquired hash value and the generated hash value are consistent, registering an identifier for uniquely identifying the video file and the hash value in a block of the blockchain; as well as The step of distributing an audio file including the audio data to other devices in association with the identifier.

Images