Quantum-Secure Digital and Physical Proof of Work

Abstract

A computer-implemented proof-of-work method is disclosed for generating and verifying blocks of a blockchain using at least one printing device. The printing device is configured to generate at least one digital image in response to printer control settings. The method includes the following steps: i) (110) determining a plurality of sequences of numbers by solving at least one cryptographic puzzle; ii) (118) selecting one digit string from the determined plurality of digit strings as a mining printer control setting; iii) (120) printing at least one initial digital image (116) including a plurality of colored pixels using a printing device having selected mining printer control settings (112) and scanning the printed image using at least one scanning device, thereby generating a mined digital image (122) having a plurality of colored pixels different from the initial digital image (116); iv) (124) using at least one processing device, comparing colored pixels of the mined digital image (122) and the task digital image (114), the task digital image (114) including a number of colored pixels that differ from the initial digital image (116). The method includes repeating steps ii) (118) through iv) (124) until the colored pixels of the mining digital image (122) and the task digital image (114) are found to be identical. In each instance of step ii) (118), a different mining printer control setting (112) is selected. The mining printer control setting (112) for which the mining digital image (122) and the task digital image (114) are found to be identical, at least within a tolerance, is used as proof-of-work for generating and validating blocks of the blockchain.

Description

[Technical field]

[0001] The present invention relates to a computer-implemented method for proof-of-work for generating and validating blocks of a blockchain using at least one printing device and the use of said method for cryptocurrency transactions etc. The method and use according to the invention may in particular be used for secure processing of transactions in the fields of smart contracts, financial services, healthcare, personal identification, cryptocurrencies and supply chains. Other applications are also possible. [Background technology]

[0002] In many applications, including financial services, healthcare, personal identification, cryptocurrencies, and supply chains, blockchain technology is an efficient technology that ensures the secure processing of transactions, such as licensing, collaborating with other companies, and selling technology.

[0003] A blockchain is a cryptographically linked list of records called blocks. Each block contains a cryptographic hash of the previous block, a timestamp, and the transaction data. By design, blockchain is resistant to data modification. It is an open, distributed ledger that allows transactions between two parties to be recorded in an efficient, verifiable, and permanent way (see en.wikipedia.org / wiki / Blockchain). When used as a distributed ledger, blockchain is usually managed by a peer-to-peer network that adheres to a protocol for inter-node communication and validation of new blocks. Each block contains a cryptographic hash of the previous block in the blockchain, linking them together. The linked blocks form a chain. This iterative process ensures the integrity of the previous block, all the way back to the first block. Blockchain technology typically requires a cryptographic hash function, a process of multiple pieces of information, and a hash function that maps data of any size to a fixed-size value so that the data in any block cannot be changed retroactively.

[0004] Non-Patent Document 1 (Eshani et al, “A study on the issue of blockchain's energy consumption”, DOI: 10.1007 / 978-981-15-0361-0_5) states that blockchain technology is one of the biggest innovative technologies developed and has potential applications in the fields of education, business, and industry. Since the birth of Bitcoin, blockchain emerged as a way to store digital information without third-party intervention. However, it is now used for various purposes other than as a simple distributed ledger. Over time, blockchain has become a major influence in various sectors of the economy and has become popular due to its immutability. However, there are also problems that blockchain faces. One of them is energy consumption. Blockchain has been found to consume an exorbitant amount of energy due to the algorithms used in its creation. Non-patent literature 2 (Johannes Sedlmeir et al., "The Energy Consumption of Blockchain Technology: Beyond Myth", Bus Inf Syst Eng 62(6):599-608 (2020), https: / / doi.org / 10.1007 / s12599-020-00656-x and Eshani Ghosh and Baisakhi Das, "A study on the issue of blockchain's energy consumption", January 2020, DOI: 10.1007 / 978-981-15-0361-0_5, Proceedings of International Ethical Hacking Conference 2019 (pp.63-75)) describes the enormous energy consumption required for blockchain technology, especially proof-of-work.

[0005] Given recent advances in computer technology, such as the development of quantum computing, there is a risk that significantly more computing power may suddenly become available to perform digital proof-of-work, which could jeopardize the security of cryptocurrencies. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Eshani et al, “A study on the issue of blockchain's energy consumption”, DOI: 10.1007 / 978-981-15-0361-0_5 [Non-Patent Document 2] Johannes Sedlmeir et al., "The Energy Consumption of Blockchain Technology:Beyond Myth", Bus Inf Syst Eng 62(6):599-608 (2020), https: / / doi.org / 10.1007 / s12599-020-00656-x and Eshani Ghosh and Baisakhi Das, "A study on the issue of blockchain's energy consumption", January 2020, DOI: 10.1007 / 978-981-15-0361-0_5, Proceedings of International Ethical Hacking Conference 2019 (pp.63-75) Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, it is desirable to provide a method and apparatus that solves the above-mentioned technical problems. In particular, a computer-implemented proof-of-work method for generating and verifying blocks of a blockchain using at least one printing device should be provided that can increase the security of the proof-of-work. [Means for solving the problem]

[0008] This problem is addressed by a computer implemented method for proof of work for generating and validating blocks of a blockchain using at least one printing device and a method of use having the features of the independent claims. Advantageous embodiments, which may be realized independently or in any combination, are set out in the dependent claims and in the entire specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In a first aspect of the present invention, a computer-implemented method for proof-of-work is proposed for generating and validating blocks of a blockchain using at least one printing device, the printing device being configured to generate at least one digital image in response to printer control settings.

[0010] The method specifically includes the following method steps, which may be performed in a given order, although different orders are possible. Furthermore, two or more method steps may be performed fully or partially simultaneously. Furthermore, one or more, or all, of the method steps may be performed once or may be performed repeatedly, such as once or several times. Furthermore, the method may include additional method steps not listed.

[0011] The method includes the steps of: i) determining a plurality of sequences of numbers by solving at least one cryptographic puzzle; ii) selecting a digit string from the determined plurality of digit strings as a mining printer control setting; iii) printing at least one initial digital image (116) including a plurality of colored pixels with a printing device having selected mining printer control settings and scanning the printed image with at least one scanning device, thereby generating a mined digital image having a plurality of colored pixels different from the initial digital image; iv) using at least one processing device, comparing colored pixels of the mining digital image and the task digital image, the task digital image including a number of colored pixels that differ from the initial digital image.

[0012] The method further includes repeating steps ii) through iv) until colored pixels of the mining digital image and the task digital image are found to be identical. In each instance of step ii), a different mining printer control setting is selected. The mining printer control setting for which the mining digital image and the task digital image are found to be identical, at least within a tolerance, is used as a proof-of-work for generating and validating blocks of the blockchain.

[0013] The term "computer-implemented" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may specifically refer, without limitation, to a process that is fully or partially implemented by using a data processing means, such as a data processing means including at least one processor. Thus, the term "computer" may generally refer to a device having at least one data processing means, such as at least one processor, or a combination or network of devices. The computer may further include one or more further components, such as at least one of a data storage device, an electronic interface, and a human-machine interface.

[0014] The term "block" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may refer to, but is not limited to, a component or element of a blockchain. A blockchain may be defined as a chain of blocks that can hold certain records, and the blocks are linked together using cryptographic principles. For further details, see Eshani et al, "A study on the issue of blockchain's energy consumption", Chapter 2, DOI: 10.1007 / 978-981-15-0361-0_5 or en.wikipedia.org / wiki / Blockchain. Each block may contain transaction data. Blocks may be linked by including a hash value of the previous block. Each block may include a cryptographic hash value of the previous block. Each block may further include a timestamp. A blockchain may include multiple linked blocks.

[0015] A block may include a header that contains several fields. In particular, the header includes information about the block version number, a cryptographic hash of the previous block header, a cryptographic hash based on all transactions in the block, time, bits, and a nonce. The structure of a block may be similar to the Bitcoin block architecture, for example as described in en.bitcoin.it / wiki / Block_hashing_algorithm. The block header may include the following fields: [Table 1]

[0016] The block version number, also denoted as "Version", the cryptographic hash of the previous block header, also denoted as "hashPrevBlock", the cryptographic hash based on all transactions in the block, also denoted as "hashMerkleRoot", and the "Time" fields may be generated in the same manner as in Bitcoin and may retain the same meaning. The time may be a timestamp as the number of seconds since 1970-01-01T00:00 UTC. This method allows for the time to be aligned with the protocol of transactions in each block. However, other times are also possible.

[0017] The term "bits" as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. Bits may define the number of pixels in the initial digital image and / or the number of pixels in the task digital image. The field "bits", e.g., 32 bits "bits", may be used to define the number of pixels in the task digital image. For example, the first 16 bits may be used to define the number of pixels in the initial digital image to be printed. The second 16 bits may be used to define the number of pixels in the task digital image. The field "bits" may define the mining difficulty. The field "bits" may be used to address the difficulty and / or printing time depending on the number of pixels per each printing and scanning iteration. The more pixels printed, the longer the printing time and the longer the iterations. Thus, the field bits can be used like Bitcoin.

[0018] The term "generating a block" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may specifically, but not limited to, refer to adding and / or generating and / or creating a new block to a blockchain. The term "proof of work" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may specifically, but not limited to, refer to a consensus process to ensure the generation of a new block of a blockchain. Before a block can be added to a blockchain, the information it contains needs to be "verified" by a network built on blockchain technology (also called a blockchain network). This may be done by solving a cryptographic puzzle, creating a so-called hash. The process of searching for a solution is usually called "mining" or "mining process". The nodes of the network may check whether the found solution is correct. If the nodes confirm its validity, the block is considered valid and can be added to the blockchain.

[0019] The term "printing device", also referred to as printer, as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art, and should not be limited to a special or customized meaning. The term may specifically, but not exclusively, refer to at least one device configured to apply, e.g. print, at least one material onto at least one printing surface or substrate, particularly in a pattern, according to a printer control setting. In particular, the printing device may include one or more of: a drum, such as an image drum; a conveyor, such as a transport belt; a laser; a lens system, such as a lens system including at least one mirror, e.g. a rotatable mirror; a cleaning element, e.g. a roll, scraper or similar cleaning means, for cleaning the drum or conveyor; a cassette, e.g. a cassette, e.g. a paper cassette, for storing one or more substrates (substrates); at least one transport element, such as a roller and / or a conveyor; and a printer control unit configured to control the printing device. In particular, the material is printed onto the surface of a drum, such as an image drum, or onto a conveyor, such as a transfer belt. For example, the printing device may include a cassette for storing one or more of the substrates, such as a paper cassette; at least one transport element, such as a roller and / or a conveyor, for example for feeding, transporting and / or discharging the substrate, in particular the paper, into, into and / or out of the printing device. The printing device may include at least one pigment collector configured to collect the pigment from the transfer belt. The printing device may include at least one suction mechanism for sucking the pigment from the transfer belt, for example into the pigment collector. Other embodiments for transferring the pigment from the transfer belt to the pigment collector may be possible, for example without using a suction mechanism. The printing device may include at least one, for example further, suction mechanism for transferring the collected pigment from the pigment collector out of the printing device. This makes it possible to guarantee a continuous operation of the printing device 24 / 7 / 365 and to avoid situations where the pigment collector has to be emptied manually when filled with pigment.The printing device may comprise at least one material reservoir configured to supply pigment for printing. The printing device may include at least one dosing mechanism. The dosing mechanism may be configured to transfer pigment from the material reservoir for printing, for example, into the printing device, thereby ensuring a 24 / 7 continuous operation of the printing device and avoiding manual recharging of a pigment reservoir in the printing device in case of an exhaustion of pigment in the pigment reservoir.

[0020] The printing device is configured to generate at least one digital image. The digital image may result from scanning an optical impression (pattern) of at least one material on a substrate and applying illumination to the scanned area. The term "digital image" (also written as digital picture) as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may represent, but is not limited to, a two-dimensional representation of a physical object. The terms image and picture are used synonymously below. The digital image may include multiple colored pixels. For example, the digital image may be a digital RGB image. The digital RGB image may be a color digital image having three color channels, one each of red (R), green (G) and blue (B). The primary colors of the digital RGB image may be red, green and blue. The RGB digital image may have a color channel for each primary color. The digital color image may include multiple image pixels, each image pixel being made from a combination of the primary colors. For example, the digital RGB image may be 24-bit or 48-bit. Each pixel in a digital RGB image can be specified by two spatial coordinates and three color values. For example, the digital image may be a digital CMYK color image, where the primary colors in the CMYK color space are black, cyan, magenta, yellow, and white. However, other color spaces are possible.

[0021] Printing may include printing an image onto a transfer belt, also referred to herein as a drum, in a printing device.

[0022] The term "printer control settings" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may specifically, but not exclusively, represent printer control information including a plurality of parameters for controlling at least one function of a printing device. For example, the printer control settings may include a character string of a predefined length. The printer control settings may include at least one item of blending information, which will be outlined in more detail below. Thus, typically, a printing device may be configured to generate text and / or images on at least one printing surface according to a printer control setting, such as one or more of a character string, a bitmap image, a vector image, a computer program, such as those provided in at least one printer control language. In particular, the printing device, and in particular at least one function of the printing device, may be controllable via at least one printer control language, such as one or more page description languages ​​(PDLs), printer command language (PCL), PostScript, XML Paper Specification, and the like.

[0023] As described above, step i) includes determining a number of digit strings by solving at least one cryptographic puzzle. The number strings may be potential mining printer control settings for transferring and / or generating a task digital image from an initial digital image. In step ii), one number string of the determined number strings is selected as the mining printer control setting. The term "mining printer control setting" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and is not limited to a special or customized meaning. The term may specifically, but not exclusively, represent a printer control setting that is expected to be used for transferring and / or generating a task digital image from an initial digital image.

[0024] The term "cryptographic puzzle" as used herein is a broad term and is given its ordinary and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may refer to any mathematical challenge with a defined difficulty, but is not limited to any particular one. Solving a cryptographic puzzle may include finding a number that generates a cryptographic hash value (also written hash value) with a defined number of leading digits. The leading digits may be defined. For example, the digits are identical. For example, the input of the cryptographic puzzle may be transactions in a block. For example, the version number of the current block, the data stored in the block, and the hash value of the previous block may be used as inputs for the hash function. The difficulty, which controls the average duration for generating a block, may be adjusted according to the computational power of the network of mining computers involved. The difficulty is set, for example, by the number of leading digits of the hash value. The number of leading digits of the hash value may be fixedly defined, such as set to a number, and / or may be automatically defined, such as using at least one difficulty algorithm. The latter may include redefining and / or adjusting the number of leading digits, such as after a defined number of generated blocks. For example, the number of leading digits may be redefined and / or adjusted for every 2016 blocks. The number of leading digits may be redefined and / or adjusted depending on the average duration for generating a block, for example, 10 minutes. The digits may be symbols or groups of symbols that represent numbers, for example, digit strings, hexadecimal numbers, etc. In particular, the numbers are potential nonces. The term "nonce" as used herein is a broad term and should be given its ordinary and custom meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may represent, but is not limited to, any number (one-dimensional) that can be used only once. One of the found nonce may be a printer control setting configured for transferring the initial digital image to the task digital image.In particular, one of the nonce may be a mining printer control setting that transfers the initial digital image to the task digital image, especially after one or more of printing, scanning, and pixelating. For example, the cryptographic hash value includes a hexadecimal number. Solving the cryptographic puzzle may include finding a hexadecimal number that generates a cryptographic hash value with a defined number of leading hexadecimal numbers, for example, 10 leading zeros. For example, step i) may include finding a nonce by solving a cryptographic puzzle, which is added to the hexadecimal number of the header of the block to generate a specific hash value, for example, a certain number of "zeros".

[0025] The cryptographic hash value may be generated using at least one hash function that takes as input the block number of the block, the data stored in the block, and the cryptographic hash of the previous block. The hash function may be any function that can be used to map data of any size to a fixed-size value. The value returned by the hash function is referred to as the hash value. The term "cryptographic hash value" as used herein is a broad term and is given its ordinary and custom meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may refer to, but is not limited to, any fixed-length numeric value that uniquely represents data. For example, a cryptographic hash value may include a hexadecimal number. The term "data" as used herein is a broad term and is given its ordinary and custom meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may refer to, but is not limited to, any information and / or machine-readable signals or symbols representative of information. Data may specifically be or include one or both of digital data and analog data. For example, the hash function may be at least one secure hash function SHA-2 selected from the group consisting of SHA-224, SHA-256, SHA-384, SHA-512, SHA-512 / 224, SHA-512 / 256. For example, the version number of the current block, the data stored in the block (including the nonce), and the hash value of the previous block may be used as inputs to the hash function.

[0026] Step ii) includes selecting one of the determined number strings as a mining printer control setting, as described above. Specifically, the method includes applying the found number string as a mining printer control setting and checking whether one of the mining control settings transfers the initial digital image to the task digital image. The mining printer control setting may be selected iteratively. The mining printer control setting found to transfer the initial digital image to the task digital image is used to generate a number that is applied as a nonce to generate and verify blocks of the blockchain, which is also referred to as a consensus mechanism.

[0027] As described above, step iii) includes printing at least one initial digital image including a plurality of colored pixels using a printing device having selected mining printer control settings, and scanning the printed image using at least one scanning device, thereby generating a mined digital image having a plurality of colored pixels different from the initial digital image.

[0028] The size of the nonce may be set before printing. For example, the size of the nonce may be set by information defining the color intensity of each color in the color space used for printing. For example, the intensity of each color in the color space, e.g., the CMYK color space, may vary in the range of 0 to 255. Thus, the structure of the nonce may be {CC-MM-YY-KK}. For example, the size of the nonce is 4 bytes to define the color intensity of the color space ranging from 0 to 255. In particular, the size of the nonce is 4 bytes to define the intensity of four colors in the color space ranging from 0 to 255. For example, the size of the nonce is 4 bytes to define the color intensity in the range of 0 to 15 for an eight-color color space, or in the range of 0 to 255 for a four-color color space, or in the appropriate range for further colors in further color spaces, and the color intensity is represented by one or two hexadecimal digits or other numbers, e.g., as decimal digits, for each pigment color. The intensity may be represented by two hexadecimal digits for each color.

[0029] The method may further include generating an initial digital image by converting at least a portion of the cryptographic hash of the previous block header into color values ​​of colored pixels. As used herein, the term "generating at least one initial digital image" is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may specifically, but is not limited to, a process of determining colors of pixels of an initial digital image. As used herein, the term "initial digital image" is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may specifically, but is not limited to, any digital image used as a starting point for mining. The initial digital image may be generated by converting at least a portion of the cryptographic hash of the previous block header into color values ​​of colored pixels of the initial digital image. For example, generating the initial digital image may include converting at least a portion of the hexadecimal of the cryptographic hash of the previous block header into RGB color for printing the initial digital image on a substrate using pigment particles according to a further color space, such as the CMYK color space. For example, the conversion from hexadecimal to color values ​​may be performed using at least one mathematical algorithm and / or at least one predetermined relationship, such as a look-up table, e.g., as described at www.rapidtables.com / convert / color / hex-to-rgb.html, in “The Image-Interface: Graphical Supports for Visual Information”, Everardo Reyes-Garcia, John Wiley & Sons, 2017, ISBN 978-1-1194-7497-5.

[0030] The generation of the initial digital image may include selecting a hexadecimal number from a cryptographic hash value of a previous block header. For example, the cryptographic hash value may be used as included in the header of the block. For example, for a first pixel of the initial digital image, the first six hexadecimal digits may be selected and converted to an RGB color. For further pixels of the initial digital image, the next six consecutive digits may be selected and converted to an RGB color. However, other embodiments of selecting a hexadecimal number from the cryptographic hash are possible. For example, the cryptographic hash value of the previous block header may be processed, for example by sorting and / or at least one further mathematical algorithm. For example, the method may include generating, for each pixel of the initial digital image, a table including rows and columns. Each row may include a different processed version of the initial cryptographic hash value. For example, for a first pixel of the initial digital image, the first six digits of the first column may be selected. For further pixels of the initial digital image, the next consecutive row and / or column may be selected.

[0031] The generation of the initial digital image may include converting the hexadecimal digits of the cryptographic hash value of the previous block header to RGB colors of significant optical differences. As used herein, the term "significant optical differences" is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. For example, the conversion from the hexadecimal digits of the cryptographic hash value to the RGB colors of the optically significant differences may be performed according to a predefined lookup table (illustratively performed for a 4-bit color space): [Table 2]

[0032] The RGB color space may be a 24-bit color space. The RGB color palette is 8 ) 3In order to achieve significant optical differentiation, only two hexadecimal digits may be used to define each RGB color.

[0033] The cryptographic hash value of the previous block header may be used to define a size and / or a shape of a pixel of the initial digital image before printing on the substrate. The hexadecimal value of the cryptographic hash value of the previous block header is preferably used to define the amount of color dots per pixel. The hexadecimal value of the cryptographic hash value of the previous block header may be used to define the amount of color dots per pixel. The method may include generating a table including a row and a column for each pixel of the initial digital image. Each row may include a different processed version of the initial cryptographic hash value. For example, the size of a first pixel of the initial digital image may be defined by the seventh row of the first column. For further pixels of the initial digital image, the next seventh row and / or column in succession may be selected. The shape of the pixel may be defined by a portion of the cryptographic hash value. For example, the seventh row may also be used for the shape and / or another row may be used to define the shape. For example, the pixels may be circular for numbers 0-4, triangular for numbers 5-8, square for numbers 9-B, and / or diamond for numbers C-F. However, other embodiments may be possible. The method may include arranging the pixels in a quadratic curve. The area size of each pixel may be set to 10 mm x 10 mm, preferably 3 mm x 3 mm.

[0034] The term "task digital image" as used herein is a broad term and is to be given its ordinary and customary meaning to those skilled in the art, and is not to be limited to any special or customized meaning. In particular, the term may refer to, but is not limited to, any digital image used as a cryptography puzzle. The task digital image includes a number of colored pixels that are different from the initial digital image. The colored pixels of the task digital image may have the same or different color values. The colored pixels of the initial digital image and / or the task digital image may be colored pixels in the RGB color space.

[0035] The task digital image may be generated by converting at least a part of the cryptographic hash value of the previous block header other than that used for generating the initial digital image into at least one color value of a colored pixel. With regard to converting at least a part of the cryptographic hash value into a color value of a pixel of the task digital image, reference is made to the generation of the initial digital image. However, it is also possible to use a part of the cryptographic hash value other than that for the initial digital image for the task digital image. However, it is also possible to use other color spaces. For example, for mining, the RGB color of the task digital image may first be automatically defined. For this purpose, for example, the last 24 bits of the cryptographic hash of the previous block may be used.

[0036] Additionally or alternatively, the task digital image may be generated using at least one random algorithm. Such random algorithms are generally known to those skilled in the art. The random numbers, such as hexadecimal numbers, generated by the random algorithm may be converted into color values. The conversion from hexadecimal numbers to color values ​​may be performed using at least one mathematical algorithm and / or at least one predefined relationship, such as a lookup table, as described, for example, in "Improving Image Performance by Using Color Lookup Tables, Adobe developer support, Technical Note #5121, 31 March 1992 or https: / / www.rgbtohex.net / hextorgb / ".

[0037] Additionally or alternatively, the task digital image may be provided by converting the transaction digital information of a block, such as the block to be added or the previous block, into color values, e.g., RGB colors or CMYK colors. The transactions may include financial transactions, such as payments, licenses, orders, invoices, and / or logistics transactions, such as deliveries, storage records, travel records, and / or planning transactions, and / or tax returns, and / or contracts, and / or personal health information, and / or the like. The term "transaction digital information" as used herein is a broad term and is to be given its ordinary and customary meaning to those skilled in the art, and is not to be limited to any special or customized meaning. The term may refer to data describing at least one transaction, also referred to as transaction data, but is not limited to such data. The transaction data may include information regarding one or more of the following: time of transaction, value of transaction, text of transaction, digital image of transaction, text of transaction, digital image of transaction, and / or the like. The transaction data may be provided in a binary format.

[0038] The mining proposed by the present invention relates to finding a mining printer control setting among a plurality of potential mining printer control settings that transfer an initial digital image to a task digital image. A miner first finds a plurality of potential mining printer control settings by solving a cryptographic puzzle, and then attempts to identify a mining printer control setting number among the plurality of potential mining printer control settings that converts an initial digital image to a task digital image. The miner who first finds a mining printer control setting that converts an initial digital image to a task digital image may win. Other miners may check the mining printer control settings.

[0039] The mining digital image has a number of colored pixels different from the initial digital image. The colored pixels of the mining digital image may be colored pixels in a CMYK color space or an RGB color space. In a 24-bit RGB color space, the difference in color code between the mining digital image and the initial digital image may be 1 for one of three colors in the RGB color space for one pixel (for example, the color codes of the pixels of the initial digital image and the mining digital image are the same, but for one pixel, the color code of the mining digital image is 4472C5, and the color code of the same pixel of the initial digital image is 4472C4).

[0040] The term "mining digital images" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may specifically, but not exclusively, refer to a digital image being generated by printing an initial digital image with a printing device and scanning the printed image with at least one scanning device by blending and / or mixing pigments with selected mining printer control settings. Printing may include printing onto a substrate. Blending may include at least one step of mixing pigments in a prescribed manner, thereby creating a blend. The printing device may be configured for use as a blending device. Specifically, the printing device is configured to receive at least one item of blending information and generate a digital image.

[0041] The printing device may in particular be configured to blend at least two materials on at least one substrate according to at least one item of blending information. In particular, the printing device may be configured to blend at least two materials according to an item of blending information, thereby for example producing a blend and blending on a substrate for receiving the blend. For embodiments of the printing device and the scanning device, reference is made to WO2021 / 001147, the entire contents of which are hereby incorporated herein in their entirety. The term "material" as used herein is a broad term and is given its usual and customary meaning to a person skilled in the art and is not limited to a special or customized meaning. The term may represent, but is not limited to, a chemical element or chemical compound, in particular a chemical element or chemical compound that is mixable with other chemical elements or chemical compounds. The material may in particular be suitable for pouring. The material may generally be in a solid state, in particular one or more of a granular solid state, a liquid state or a gaseous state. In particular, the material may be or include at least one of a powder or a liquid. The material may be a homogenous single material. Alternatively, the material may comprise multiple components, homogeneously or heterogeneously mixed. Thus, the material may be a mixture or may itself be a composite. By way of example, the material may be or may comprise a liquid, which may, by way of example, comprise at least one solvent and at least one chemical compound dissolved, emulsified or dispersed in the at least one solvent. The solvent may form part of the material, or the at least one chemical compound may be considered the material and the solvent may simply be considered an adjuvant or additive to the material.

[0042] The term "blending" as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art and should not be limited to a special or customized meaning. The term may specifically, but not exclusively, refer to the process of mixing at least two materials in a defined manner, thereby creating a blend. The terms blending and mixing are used interchangeably herein. The process of creating a blend may include further steps, such as temperature change or temperature treatment of the at least two materials. Mixing is performed in a variety of ways, depending on the nature of the at least two materials. As an example, if the at least two materials include powders, mixing may include co-dispensing or subsequent dispensing of the powders into a common receptacle, including the option of stirring the mixture. Additionally or alternatively, if the at least two materials include liquids, mixing may also include co-dispensing or subsequent dispensing of the liquid into a common receptacle, including the option of stirring the mixture. Additionally or alternatively, mixing may also include a printing process, such as inkjet printing of the at least two materials onto a common substrate, as outlined in more detail below. Additionally or alternatively, blending may include other types of mixing steps of at least two materials, such as mixing at least two materials on at least one common substrate. As an example, blending may include one or more electrostatic deposition steps, such as electrostatic deposition of at least two materials on a common substrate, e.g., on a surface carrying an electrostatic charge. Thus, in particular, blending and / or mixing may include electrostatic deposition in a printing process. For example, blending and / or mixing may include electrostatic deposition of at least two electrostatically charged materials on an electrostatically neutralized surface in a printing process. In this way, the materials may be mixed, thereby at least temporarily changing their charge. In particular, blending and / or mixing may include electrostatic deposition in a laser printing process, such as a process typically performed in a laser printer.In particular, at least two materials, e.g., pigments, may be deposited onto an equally charged image roll that is, for example, first electrostatically charged and then electrostatically neutralized in certain areas, e.g., by using lasers and / or LEDs. These deposited materials may then be drawn off and / or removed from the image roll, as one example, by an oppositely charged substrate, e.g., oppositely charged paper.

[0043] Blending may leave the materials unchanged or may completely or partially change their properties. Thus, by way of example, the materials may simply be mixed without any chemical change. Additionally or alternatively, the materials may be mixed to change their chemical properties. The latter may be done especially when the materials contain solvents that may completely or partially evaporate during or after mixing. In this case, the materials may also additionally or alternatively react with each other, completely or partially, thereby generating at least one reaction product.

[0044] The term "blend" as used herein is a broad term and is given its usual and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may refer to, but is not limited to, a mixture of at least two materials. Specifically, the mixture may be present in at least one receptacle and / or on at least one substrate. The mixture may generally be in one or more of a solid state, specifically a granular solid state, a liquid state, or a gaseous state. Specifically, the mixture may be or include at least one of a powder or a liquid. The mixture may be in the same state as the materials or in a different state. As an example, at least one of the materials may be in a liquid state and the mixture may be in a solid state, for example after drying. Thus, as an example, at least two materials may be mixed in a mixing step in a liquid state, which may be followed by drying, which may evaporate at least one solvent and / or which may change the chemical nature of the mixed materials. As an example, the mixing process may involve printing at least two materials in a liquid state onto at least one substrate followed by a drying or solidifying process, resulting in a blend in a dry or solid state, as another example, may involve a phase change process such as curing or solidification of the materials after mixing.

[0045] The term "item of blending information" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may specifically, but not exclusively, represent at least one item of information describing a defined compounding process. The at least one item of blending information may also represent the mixing process itself, such as the manner in which at least two materials are mixed, e.g., the process parameters of the mixing process. Additionally or alternatively, the at least one item of blending information may represent the materials to be mixed, such as the amounts to be mixed in the mixing process, e.g., the mass or volume of the materials.

[0046] The term "blending device" as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may specifically, but not exclusively, refer to a device configured to perform the blending process described above. Specifically, as outlined in more detail below, the blending device may include at least one supply or container (reservoir) for each material. The blending device may also include at least one blending element, such as a nozzle, an agitator, a printer, a mixer, etc.

[0047] Thus, the term "blend" as used herein is also a broad term and should be given its ordinary and customary meaning to those skilled in the art, and should not be limited to any special or customized meaning. The term may refer to, but is not limited to, a mixture of at least two materials. Specifically, the blend may be present on a substrate or in a receptacle. Specifically, the blend may include a finite amount of material.

[0048] The mining digital image generation may include detecting at least one material property of the blend using at least one detector. The term "material property" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to any special or customized meaning. The term may represent any property of a material, such as, but not limited to, that of a blend. The property may represent, in particular, one or more of a physical property, a chemical property, or a biological property. In particular, the material property may include at least one of a mechanical property or an optical property of the material. The material property may represent, in particular, a measurable property of the respective material. More particularly, the at least one material property may be or may include at least one color of the blend. Additionally or alternatively, at least one property selected from the group consisting of: specific density of the blend; volume of the blend; weight of the blend; optical property of the blend; spectral composition of the blend, specifically the color spectrum of the blend; color intensity of the blend; and viscosity of the blend. Other material properties may be used alternatively or additionally.

[0049] The step of specifically detecting at least one material property of the blend may include generating at least one item of measurement information relating to the material property. The at least one item of measurement information may thus generally represent a measurement result of the at least one material property, such as at least one numerical measurement indicative of or characteristic of the at least one material property of the blend. Thus, by way of example, the at least one item of measurement information may include at least one of the following: a specific density measurement of the blend, a volume measurement of the blend, a weight measurement of the blend, an optical property measurement of the blend, a color measurement of the blend, a spectral composition measurement of the blend, in particular a color spectrum measurement of the blend, a color intensity measurement of the blend, a viscosity measurement of the blend. These measurements may be or include, by way of example, a single or multiple numerical values, such as distributions, spectra, etc., respectively. In particular, the at least one item of measurement information may be or include, at least one numerical value, such as a digital value.

[0050] The term "detection" as used herein is a broad term and is given its ordinary and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may specifically, but not limited to, refer to a process that generates information about a characteristic or measurable variable, and qualitative and / or quantitative information may be retrieved. The term may specifically, but not limited to, refer to a process that measures at least one measurable variable of a physical object. Thus, the term "detector" as used herein is a broad term and is given its ordinary and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may specifically, but not limited to, refer to any device configured to perform a detection process, such as a device having at least one sensor for measuring at least one measurable variable of an object. By way of example, the sensor may include one or more of a weight sensor, specifically a scale, a volume sensor, a density sensor, a color sensor, and a particle size distribution sensor. Other sensors may be used additionally or alternatively.

[0051] At least one item of blend information may specifically include n blend variables, where n is a positive integer. The term "blend variable" as used herein is a broad term and is given its usual and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may specifically, but is not limited to, a variable that quantitatively or qualitatively describes at least one aspect or parameter of a blend. As an example, the blend variable may represent the detection of a blending process of at least two materials, the amount of blending or the flow of materials, etc. Furthermore, m material properties of the blend may be detected, where m is a positive integer. Specifically, the number of detected material properties m may be equal to or greater than the number of blend variables n. In other words, preferably, m≧n. In further other words, in particular, the information generated by detection may be at least as large as the information used to generate the blend, where the term "information" may represent the numbers n and m, respectively, and / or, in general, the number of degrees of freedom and / or the logarithm of the degrees of freedom, such as log n or log m, respectively.

[0052] In particular, the at least two materials to be blended may be different materials, in particular materials that differ with respect to at least one property selected from the group consisting of chemical properties, in particular chemical composition; optical properties, in particular optical appearance such as one or more of color, transparency, brilliance; mechanical properties, in particular one or more of particle size, particle size, density, viscosity or flowability; electrostatic charging properties; compressibility; crystallinity; particle shape. Further, in addition or alternatively, other properties may be used.

[0053] The at least two materials may specifically include bulk materials and / or loose materials. The at least two materials may each independently be selected from the group consisting of solid materials, gaseous materials, and liquid materials. More specifically, the at least two materials may each independently be selected from the group consisting of and / or may include at least two materials selected from the group consisting of: - powders, in particular powders selected from the group consisting of: Inorganic powders, especially those made of minerals; organic powders, in particular organic powders made of polymers; Pigments; Toner powder; a liquid, in particular a liquid selected from the group consisting of a pure liquid, a suspension, an emulsion or a solution, more in particular one or more of liquid colours and inks.

[0054] In this specification, the terms material and pigment can be used synonymously. Thus, the term pigment may include color particles, powders, and liquids containing these particles. The term pigment may include pure pigments and / or pigments with at least one polymer coating, such as styrene acrylate copolymers, polyester resins, styrene butadiene copolymers, or similar polymers. In particular, the term pigment may refer to toner powders. In the context of the present invention, any suitable pigment can be used. In the context of the present invention, it is also possible to use mixtures, including, for example, one or more pigments or one or more pigment toner powders.

[0055] In the context of the present invention, the amount of pigment used may vary. Preferably, the amount of pigment used is 10 -15 g / cm 2 ~1g / cm 2 More preferably, the range is 10 -9 g / cm 2 ~10 -3 g / cm 2 The range is.

[0056] The particle size of the pigments used is preferably in the range from 10 nanometers to 1 mm, preferably in the range from 100 nanometers to 100 micrometers.

[0057] Preferably, suitable pigments are selected from inorganic materials, preferably metal oxides, metal oxides, preferably metal oxides of natural origin. Suitable may be, for example, pigments selected from iron oxides. Iron oxide pigments are relatively low-cost materials, resist color change due to exposure to sunlight, have good chemical resistance, and are stable under normal ambient conditions. Iron oxide has been found to be particularly suitable, as it is easy to recycle and reuse. For example, iron oxide pigments can be recovered and used as a raw material in steel production, thus avoiding the disposal of used pigments as waste.

[0058] Suitable iron oxides are also available as natural pigments. Suitable red pigments may be derived from hematite, yellow and brown pigments such as ochre, sierra, amber may be derived from limonite, and magnetite provides black iron oxide pigments. Additionally, synthetic pigments, particularly metal oxides such as iron oxides, produced under controlled conditions to provide excellent uniformity in particle size, distribution and shape, may be used in accordance with the present invention to improve color quality and chemical purity.

[0059] Pigments from natural sources are suitable for the process of the present invention, such as pigments selected from natural organic materials, e.g. organic materials from plants, animals and minerals. Also suitable are pigments selected from synthetic organic materials, e.g. azo pigments. Suitable mineral pigments are, for example, ochre, sienna, azurite, cobalt or ultramarine. Spinel may also be used. Ochre is usually red or yellow, obtained from iron ore or ferruginous clay. Sienna is a type of limonite clay, which produces a deep red color from ferric oxide. Azurite is found in the upper oxidized parts of copper ore deposits. Ultramarine can be obtained from lapis lazuli or can be produced artificially. Spinel is yellow, orange, turquoise or blue. Further examples include Carmine Lake Natural Red 4 (cochineal), Natural Yellow 3 Lake (botanical), Madder Lake Natural Red 9 (madder root), Indigo Lake Natural Blue 2 (woad), Chlorophyllin Green Lake (botanical), vegetable or bone black, titanium white, iron oxide, talc, chalk, kaolin, and other earth pigments.

[0060] According to a further embodiment of the invention, preferably at least 20%, more preferably 30%, most preferably at least 40% of the pigments used should be of natural origin, i.e. derived from natural products other than products of the petrochemical industry by simple separation or purification steps. Other embodiments are possible. For example, 100% of the pigments used may be of natural origin.

[0061] In the context of the present invention, the term pigment also includes pigments that are visible under UV light. Environmentally friendly and eco-friendly pigments may also be used, for example pigments from Clariant available from Ecotrain label, such as pigments selected from the group: Novoperm Yellow HR 72, Hostaperm Blue B2G 03, Hostaperm Green GNX 01, Hansa Brilliant Yellow 2GX 72-S, Hostaperm Yellow H3G EDW VP 5131, https: / / www.clariant.com / de / Solutions / Products / 2014 / 10 / 14 / 10 / 39 / Novoperm-Orange-HL-71 "Novoperm Orange HL 71, and Hostaperm Blue B2G-EDS VP 3491.

[0062] In the context of the present invention, it is also possible to use effect pigments, such as, for example, absorption pigments, metallic effect pigments, pearlescent pigments. Metallic or metallic effect pigments are usually composed of flakes or platelets of aluminium, copper, copper-zinc alloys, zinc and other metals. Suitable pearlescent pigments are, for example, mica-based pigments, but also pigments based on silica or alumina flakes. Pigments of natural mica coated with a thin film of metal oxide, such as TiO2 or iron oxide, are suitable. Furthermore, silica flakes (SiO 2 ) or alumina (AL 2 O 3 ) can be used in the context of the present invention. Suitable substrate-free pearlescent pigments are, for example, natural pearl essences, basic lead carbonate, bismuth oxychloride, finely divided iron oxide and TiO 2 It's a flake.

[0063] Energy consumption can be improved, especially if the above-mentioned pigments are used, such as "natural pigments", which do not require energy input for chemical synthesis. The use of natural pigments in printers can reduce electrical energy consumption by 99% compared to public data on Bitcoin blockchain technology (see publication above). Thus, the invention makes a significant contribution to reducing costs and CO2 emissions.

[0064] The blending of the at least two materials may be performed according to at least one item of blending information. The at least one item of blending information may in particular include at least one of the following: amounts of the at least two materials to be blended; weights of the at least two materials to be blended; volumes of the at least two materials to be blended; blending ratios of the volumes of the at least two materials to be blended; blending ratios of the weights of the at least two materials to be blended; mixing instructions for mixing two or more continuous or discontinuous flows of the at least two materials to be blended; printing instructions for blending the at least two materials to be blended, such as tilt information for blending the at least two materials to be blended using raster images with different tilts (e.g. raster images generated by a raster image processing device) (e.g. raster images generated by a raster image processor (RIP) of a printer), etc. Furthermore, additionally or alternatively, other types of blending information may be used.

[0065] The at least two ingredients may be fed to the blending device continuously or discontinuously. Thus, by way of example, the blending device may include at least two containers (reservoirs) for the at least two ingredients to be blended. However, additionally or alternatively, other means of feeding ingredients to the at least one blending device are also possible. Thus, by way of example, in addition to or instead of using at least one reservoir for the at least one ingredient, a continuous feed is also possible.

[0066] The blending device may further include at least one receiving element for receiving the blend. As used herein, the term "receiving element" may generally refer to any element configured to receive the blend. The receiving element may specifically have at least one receiving surface and / or at least one receiving material for receiving the blend. Thus, by way of example, the at least one receiving element may specifically include at least one element selected from the group consisting of: a receiving vessel for receiving the blend; a substrate for receiving the blend. The at least one receiving element may be a stationary receiving element and / or a moving receiving element, such as a rotatable receiving element. By way of example, the receiving element may include at least one substrate, e.g., a substrate having at least one substrate surface, which may be or may include a planar substrate surface and / or may be or may include a curved substrate surface. By way of example, the receiving element may include at least one drum, such as a rotating drum, having a receiving surface for receiving the blend. The blend may be deposited directly or indirectly by using a blending device, in particular a rotating drum, such as a drum to which the blend is temporarily fixed, for example electrostatically, such electrostatic drums being commonly known in the art of printing, such as laser printing.

[0067] If the receiving element comprises at least one drum, the drum may in particular be a rotating drum. The method may then further comprise at least one cleaning step, in particular removing the blend from the receiving surface of the drum, after detecting the at least one material characteristic. By way of example, powders and / or pigments may be dispensed onto the rotating drum and may in particulately be fixed to the surface of the rotating drum by electrostatic forces. During fixing of the blend to the surface of the rotating drum, at least one material characteristic of the blend on the surface may be detected, for example by optical reading. By way of example and as outlined in more detail below, a color may be detected and then converted into binary information, for example a string of binary numbers. The drum may then be cleaned, for example by rotating the drum by 90° to a cleaning position.

[0068] A similar procedure may also be performed using inkjet printing directly onto the surface of the drum and / or onto a moving substrate, such as a paper substrate, optionally without electrostatic fixation. The drum may be cleaned for reuse after detecting the at least one characteristic. Thus, by way of example, the blending device may include at least one inkjet printer. A material, which may be a liquid material or include a liquid material, may be inkjet printed onto at least one receiving element, such as onto at least one rotating drum and / or onto at least one substrate. Then, detection of at least one material characteristic may be performed, such as detection of at least one optical characteristic, for example by optical reading. By way of example, a color may also be detected and then converted into binary information, such as, for example, a string of binary numbers. Then, the drum may be rotated to a cleaning position and cleaned, for example by rotating the drum 90°. Additionally or alternatively, besides cleaning the at least one receiving element, a new receiving element or a new part of the receiving element may be used for further steps, such as further printing or repeating the blending and detection.

[0069] The blending device may specifically include at least one blending element for producing a blend. The term "blending element" as used herein is a broad term and should be given its usual and customary meaning to those skilled in the art and should not be limited to a special or customized meaning. The term may refer, without limitation, to any element, device or combination of elements configured to specifically blend at least two materials, such as by mixing the at least two materials before, during or after deposition onto at least one optional receiving element. By way of example, the at least one blending element may be or include at least one element selected from the group consisting of: a dispenser for dispensing at least one of the two materials continuously or discontinuously; a printer for printing at least two materials onto at least one receiving element, specifically onto at least one substrate, specifically at least one printer selected from the group consisting of: an inkjet printer, a laser printer. Furthermore, additionally or alternatively, other types of blending elements may be used. Thus, by way of example, the compounding element may be or may include at least one of a mixing element, a dispenser, a nozzle, and an extruder.

[0070] The printer may in particular be configured to blend at least two materials on at least one substrate according to at least one item of blending information. In particular, the printer may be configured to blend at least two materials according to an item of blending information, thereby generating a blend on a substrate for receiving the blend, for example. The substrate may in particular be or include at least one carrier medium, for example a carrier medium selected from the group consisting of a glass carrier, for example a glass plate or sheet; a plastic carrier, for example a plastic plate or sheet; a paper carrier, for example a paper sheet; a canvas. Other substrates may also be used. By way of example, the substrate may be part of the printer itself or may be embedded within the printer. In particular, the substrate included in the printer may be a reusable carrier medium, such as a medium having a cleanable surface, for example a printer drum, for example a rotating drum.

[0071] The printer may further be configured to blend at least two materials such that at least one pattern, in particular at least one interference pattern, is generated. The at least two materials blended by the printer may in particular be different materials, in particular materials that differ with respect to at least one property. As an example, the at least two materials blended by the printer may differ in at least one property selected from the group consisting of chemical properties, in particular chemical composition; optical properties, in particular optical appearance such as one or more of color, transparency, brilliance; mechanical properties, in particular one or more of particle size, particle size, density, viscosity, flowability; electrostatic chargeability; compressibility; crystallinity; particle shape.

[0072] The method may include converting the detected material properties into color values ​​of pixels for generating the mined digital image. The conversion may be performed using at least one data processing device configured to apply at least one conversion algorithm to the material properties. The conversion of the at least one material property into color values ​​may be performed in a computer-implemented manner. Thus, the conversion of the at least one material property into color values ​​is performed by using at least one data processing device configured to apply at least one conversion algorithm to the material properties. The term "data processing device" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art and should not be limited to a special or customized meaning. The term may refer to, but is not limited to, a computer or computer system having at least one processor and optionally having at least one data storage device. Here, by way of example, the processor may include at least one integrated circuit configured to execute computer-readable instructions. The processor may additionally or alternatively be or include at least one application specific integrated circuit and / or at least one field programmable gate array. Configuring the data processing device to apply at least one transformation algorithm may, as an example, be performed by providing a plurality of computer-readable instructions to the data processing device, for example via at least one data storage device and / or via at least one interface.

[0073] The term "processor", as used herein, also referred to as processing device, is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may specifically, but not exclusively, refer to any logic circuit configured to perform basic operations of an electronic device or system, and / or generally to a device configured to perform calculations or logical operations. In particular, a processor may be configured to process basic instructions that run a device or system, such as a computer. As an example, a processor may include at least one arithmetic logic unit (ALU), at least one floating point unit (FPU), such as a math coprocessor or numeric coprocessor, a number of registers, specifically configured to provide operands to the ALU and store results of operations, and memory, such as an L1 cache memory and an L2 cache memory.

[0074] The term "algorithm" as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, and is not limited to any special or customized meaning. The term may specifically, but is not limited to, represent multiple process steps performed in series and / or in parallel. An algorithm may specifically include one or more mathematical operations applied to at least one input variable. As a result, the term "conversion algorithm" may specifically represent an algorithm that performs a conversion process to convert material properties to color values ​​using one or more mathematical operations applied to at least one input variable. The conversion of material properties to color values ​​may be performed in a single step or in multiple steps.

[0075] The conversion of the material properties into color values ​​may include subjecting the at least one material property to at least one test, in particular to at least one predefined test. The at least one test may be or may include a direct or indirect comparison of the at least one material property with at least one comparison value, at least one comparison value range, etc., such as by using at least one item of measurement information. Other mathematical tests are generally feasible and may be applied. Depending on the result of the at least one test, RGB values ​​may be generated. The conversion of the material properties into color values ​​may in particular include a comparison of the at least one material property with at least one threshold value, including the option of using at least one item of measurement information representing the material property. Depending on the result of this comparison, at least one numerical value may be assigned to the material property for each primary color.

[0076] Preferably, the Meinung digital image may be generated by scanning, in particular digitally scanning, the blend or at least an area of ​​interest of the blend. The digital scanning may be performed using at least one scanning device. The term "scanning device" as used herein is a broad term and should be given its usual customary meaning for a person skilled in the art and should not be limited to a special or customized meaning. The term may specifically, but not exclusively, describe a device configured to detect at least one property of at least one object and / or element, for example a blend. In particular, the scanning device may be configured to inspect and / or detect at least one material property of the blend. By way of example, the scanning device may have at least one scanning element configured to optically record and / or capture spatially resolved one-dimensional, two-dimensional or three-dimensional optical information of the blend. Thus, for example for optical detection, the scanning device may include at least one sensor, for example an optical sensor, in particular an image sensor, for example at least one photosensitive capacitor, at least one charge-coupled device (CCD), etc. The scanning device may include, for example, at least one CCD chip and / or at least one CMOS chip. In particular, the scanning device may be configured to detect an optical signal of the blend, for example the blended powder components and / or the mixed powder components, for example by using an optical system. In particular, the scanning device may be configured to convert, for example resolve, the optical signal of the blend into primary colors, for example red, green, blue, for example by using a prism. The scanning device may be configured to convert the optical signal, such as the optical signal converted into primary colors, into at least one digital image, for example by using at least one sensor, such as a sensor including a number of photosensitive capacitors. Furthermore, the scanning device may include at least one illumination element, such as an element configured to illuminate the blend, and the scanning device may be configured to detect at least one characteristic of the blend using the reflection of the blend. Here, the scanning device may also be referred to as a scanner.The scanning device may specifically be or include a device selected from the group consisting of a CCD scanner, a CIS scanner, a camera, and a film. In particular, the scanning device may include at least one optical detection system including one or more of an optical detector, an image sensor, a photomultiplier tube (PMT), such as a vacuum tube that converts incident photons into an electrical signal, and a silicon photomultiplier tube (SiPM), such as a solid-state device that converts incident photons into an electrical signal. The scanning device may specifically include at least one processor, which may be configured to control at least one scanning operation of the scanning device.

[0077] The scanning may be performed, for example, using light having a wavelength in the range of 10 nm to mm, preferably 300 nm to 800 nm, during scanning. 2 The luminous intensity per unit is preferably 0.001 lm / m 2 From 1,000,000 lm / m 2 and more preferably in the range of 10 lm / m 2 From 1,000,000 lm / m 2 The range is.

[0078] The wavelength spectrum may be set by at least one LED light emitting light with a color temperature of, for example, 3,000K.

[0079] The local intensity of light on a printed pixel may be defined by at least one lens or lens system, which may be configured to generate light and dark areas. For example, the lens or lens system may include a magnifying glass foil. Regarding embodiments of the printing device, the scanning device and the pigments, reference is made to WO2021 / 001147, the entire content of which is hereby incorporated herein.

[0080] The method may include a combination of digital proof-of-work and blockchain technology, where first, a cryptographic puzzle is solved by finding potential nonces that, when added to the hexadecimal digits of the block header, generate a specific hash value, for example a certain number of "zeros", and in a second step, these nonces are applied as mining printer control settings to prove whether the mining printer control settings can transfer the initial digital image to the task digital image, especially after printing and pixelation. This physical step of printing and scanning becomes the bottleneck in the processing time, so the computer does not need to be faster than this period. Therefore, it is the printer speed, not the computing power, that governs the frequency of hashing.

[0081] The method may be performed with different and / or adjustable mining difficulty. The mining difficulty may be adjustable by one or more of the following variables: amount of pigment color, size of the initial digital image, size of the task digital image, number of pixels per same printer control setting, pixel color error tolerance (e.g., red ±10%), total error tolerance (10 pixels out of 100 pixels are wrong), rastering, tilt, moiré effects, etc. For example, the method may include continuously changing the size of individual pixels, e.g., 6 dots instead of 4 dots, and / or changing the pixelation settings, e.g., 13 pixels, and even changing the lighting during scanning, especially for additional security. This means that the work needs to be done multiple times, further increasing the cost for the attacker. Setting up a model such as a simulation to replace printing and scanning is very complicated, if possible at all. In particular, the pre-consumption of pigments required for printing would require at least 10 million tons of production per year worldwide.

[0082] The method includes, in step iv), comparing, with at least one processing device, colored pixels of the mining digital image and the task digital image. The method includes repeating steps ii) through iv) until the colored pixels of the mining digital image and the task digital image are found to be identical. In each case, a different mining printer control setting is selected in step ii). The mining printer control setting for which the mining digital image and the task digital image are found to be identical, at least within a tolerance, is used as proof-of-work for generating and validating blocks of the blockchain.

[0083] The comparison of color pixels of the mining digital image and the task digital image may be performed on a pixel by pixel basis. The comparison of colored pixels of the mining digital image and the task digital image may be performed after grouping colored pixels of the mining digital image or / and the task digital image by pixelation. In particular, the method may comprise pixelating the mining digital image and / or the task digital image. The pixelation may comprise dividing the mining digital image and / or the task digital image into pixels, in particular into a predefined number of pixels. For example, the predefined number of pixels of the mining digital image may correspond to the number of pixels of the task digital image. For example, the predefined number of pixels may depend on the difficulty level of mining.

[0084] The method may include determining a color code of the pixelated mined digital image by converting the colored pixels, for example, into a hexadecimal or binary number. For example, the conversion of color values ​​into hexadecimal numbers may be performed using at least one mathematical algorithm and / or at least one pre-determined relationship, such as a look-up table, for example, as described at www.farben-umrechnen.de or in "The Image-Interface: Graphical Supports for Visual Information", Everardo Reyes-Garcia, John Wiley & Sons, 2017, ISBN 978-1-1194-7497-5. The hexadecimal number may be further converted to a binary code by using at least one predetermined relationship, such as at least one mathematical algorithm and / or a lookup table, as described, for example, in “Improving Image Performance by Using Color Lookup Tables, Adobe developer support, Technical Note #5121, 31 March 1992” or at https: / / www.rgbtohex.net / hextorgb / .

[0085] Comparing color pixels of the mining digital image and the task digital image may include comparing color codes of the pixelated mining digital image and the task digital image. The comparing may include determining whether the mining digital image and the task digital image are identical within at least a predefined pixel color tolerance. The mining digital image and the task digital image may be considered identical within a pixel color error tolerance of ±30% for each color of pixel, preferably ±10% for each color of pixel, more preferably ±3% for each color of pixel. Additionally or alternatively, an overall matching of the mining digital image and the task digital image may be determined. The mining digital image and the task digital image may be considered identical within an overall error tolerance of 10% of deviating pixels, preferably 5% of deviating pixels, more preferably 1% of deviating pixels. The comparison may be performed by a processing device of the node, for example a printing device.

[0086] The method may include determining, by the nodes of the network, whether the mining digital image and the task digital image are identical, at least within a predefined tolerance. The pixel color error tolerance of the miner performing the method may be tighter compared to the predefined tolerance of the node. This may ensure that each of the nodes is able to verify that the discovered mining printer control settings are correct within the tolerance, even if the printing device has deviating accuracy. The larger error tolerance may take into account that the printing devices of the nodes do not usually operate identically compared to each other. If the printer control setting number is verified by multiple other nodes, for example 10 or more different other nodes, the proof of work is correct and a defined amount of tokens may be transferred to the node's wallet. Other miners may also generate the same mining digital image and may verify the nonce in this manner. All mining printer control settings that are outside the error tolerance may be rejected. All mining printer control settings that are within the error tolerance may be accepted. Thus, the first one to find it may add a block to the chain and earn a crypto coin reward. The rewards based on mined cryptocurrency units and transaction fees may be the same as for Bitcoin mining, except that printer capacity is used instead of computing power, and pigments are used instead of electricity. The printing device may be implemented in the blockchain network in the same way as the mining computer, and may in particular perform the same functions.

[0087] The method may include at least one calibration step: a number of pre-specified color fields, such as the primary colors of the color space used, may be provided and printed together with the mined digital image, allowing for calibration of the scanning results.

[0088] The method may include generating a header for the subsequent block that includes information about a block version number, a cryptographic hash of the previous block header, a cryptographic hash based on all transactions in the block, a time, a bit, and a nonce. The nonce may be a mining printer control setting discovered when transferring the initial digital image to the task digital image.

[0089] The proposed method has several advantages. In particular, it is quantum-safe and allows for energy-efficient proof-of-work. State-of-the-art blockchain cryptocurrencies require prohibitive CO2 emissions. 2 For environmental and security reasons, it is possible to revolutionize the performance of current cryptocurrency blockchain technology, as it is subject to the risk of being suddenly attacked by new supercomputers (51% attack). As outlined above, the proof-of-work methods disclosed herein may be fully or partially computer-implemented by at least one computer or computer network. Steps i) to iv) may also be partially computer-implemented or computer-assisted.

[0090] The present invention therefore also discloses a computer program and a computer program product having program code means for fully or partially executing or supporting the method for proof of work according to the present invention in one or more embodiments encompassed herein, when the computer program product or computer program is executed on a computer or a computer network. In particular, the program code means may be stored on a computer readable data carrier and / or on a computer readable storage medium. Disclosed and proposed herein is a computer program comprising computer executable instructions for executing the method according to the present invention in one or more embodiments encompassed herein, when the program is executed on a computer or a computer network. In particular, the computer program may be stored on a computer readable data carrier and / or on a computer readable storage medium.

[0091] As used herein, the terms "computer-readable data carrier" and "computer-readable storage medium" may in particular denote a non-transitory data storage means such as a hardware storage medium on which computer-executable instructions are stored. A computer-readable data carrier or storage medium may in particular be or include a storage medium such as a random access memory (RAM) and / or a read-only memory (ROM).

[0092] Thus, in particular, one, more than one or all of the method steps i) to iv) set out above may be carried out using a computer or a computer network, preferably using a computer program.

[0093] Further disclosed and proposed herein is a computer program product having program code means for carrying out the method according to the invention in one or more of the embodiments encompassed herein when said program is executed on a computer or a computer network. In particular, said program code means may be stored on a computer readable data carrier and / or on a computer readable storage medium.

[0094] Further disclosed and suggested in this specification is a data carrier having a data structure stored thereon, which may be loaded into a computer or a computer network, such as a working memory or a main memory of a computer or a computer network, and subsequently perform a method according to one or more embodiments disclosed in this specification.

[0095] Further disclosed and proposed herein is a computer program product having program code means stored on a machine readable carrier for executing a method according to one or more embodiments disclosed herein when the program is executed on a computer or a computer network. In this specification, a computer program product refers to a program as a tradeable product. The product may generally be present in any form, such as a paper medium, or on a computer readable data carrier and / or on a computer readable storage medium. In particular, the computer program product may be distributed via a data network.

[0096] Finally, disclosed and suggested herein is a modulated data signal containing instructions readable by a computer system or computer network for carrying out a method according to one or more embodiments disclosed herein.

[0097] With reference to computer-implemented aspects of the invention, one or more, or even all, of the method steps of the methods according to one or more of the embodiments disclosed herein may be performed using a computer or a computer network. Thus, in general, any of the method steps involving providing and / or manipulating data may be performed using a computer or a computer network. In general, these method steps may include any of the method steps, except those that typically require manual effort, such as certain aspects of providing a sample and / or performing the actual measurement.

[0098] Specifically, the following is further disclosed herein: a computer or computer network comprising at least one processor, the processor being adapted to execute a method according to one of the embodiments described herein, a computer-loadable data structure adapted to carry out a method according to one of the embodiments described herein while said data structure is executed on a computer, a computer program adapted to carry out a method according to one of the embodiments described herein while the program is running on a computer, a computer program comprising program means for carrying out a method according to one of the embodiments described herein while said computer program is being run on a computer or on a computer network, a computer program comprising program means according to the embodiment, the program means being stored on a computer readable storage medium; - a storage medium, on which a data structure is stored, the storage medium being adapted to carry out a method according to one of the embodiments described herein after the data structure has been loaded into a main and / or working storage device of a computer or a computer network, and A computer program product having program code means, which may be stored on a storage medium or is stored on a storage medium, for performing a method according to one of the embodiments described herein when the program code means is executed on a computer or on a computer network.

[0099] In a further aspect of the present invention, a blockchain based on a digital image is disclosed. The blockchain comprises a plurality of linked blocks. The blockchain is generated by using one of the proof-of-work methods according to the invention described above or as described in detail below. For definitions and embodiments, reference is therefore made to the description of the proof-of-work methods.

[0100] In a further aspect, the use of the computer implemented method for proof of work according to any one of the preceding claims is disclosed for one or more purposes of secure processing of transactions in the fields of mining, non-fungible tokens, smart contracts, financial services, healthcare, personal identification, cryptocurrencies, supply chains, secure labels for trading cryptocurrencies. Other applications are possible.

[0101] As used herein, the terms "have", "comprise", "include" or any grammatical variants thereof are used in a non-exclusive sense. Thus, these terms may refer to the situation where there are no further features in the entity described in this context, other than the features introduced by these terms, as well as the situation where there are one or more further features. As an example, the expressions "A has B", "A comprises B" and "A includes B" may refer to both the situation where there are no other elements in A besides B (i.e., A consists only of B) and the situation where, besides B, one or more further elements are present in the entity A, such as element C, elements C and D, or even other elements.

[0102] Furthermore, it should be noted that the terms "at least one," "one or more," or similar expressions indicating that a feature or element may be present one or more times, are typically used only once when introducing each feature or element. In most cases, the expressions "at least one" or "one or more" will not be repeated when referring to each feature or element, regardless of the fact that each feature or element may be present one or more times.

[0103] Furthermore, as used herein, the terms "preferably", "more preferably", "particularly", "more particularly", "particularly", "more particularly" or similar terms are used in combination with any feature without limiting the possibility of substitution. Features introduced by these terms are therefore optional features and are not intended to limit the scope of the claims in any way. The invention can be practiced with alternative features, as the skilled artisan will recognize. Similarly, features introduced by "in an embodiment of the invention" or similar expressions are intended to be optional features, without any limitation on alternative embodiments of the invention, without any limitation on the scope of the invention, and without any limitation on the possibility of combining the feature so introduced with other optional or non-optional features of the invention.

[0104] In summary, without excluding further possible embodiments, the following embodiments may be envisaged:

[0105] "Embodiment 1" A computer-implemented method for proof-of-work for generating and validating blocks of a blockchain using at least one printing device, the printing device being configured to generate at least one digital image in response to printer control settings, the method comprising the steps of: i) determining a plurality of sequences of numbers by solving at least one cryptographic puzzle; ii) selecting a digit string from the determined plurality of digit strings as a mining printer control setting; iii) printing at least one initial digital image including a plurality of colored pixels with a printing device having selected mining printer control settings and scanning the printed image with at least one scanning device, thereby generating a mined digital image having a plurality of colored pixels different from the initial digital image; iv) using at least one processing device, comparing colored pixels of the mining digital image and the task digital image, the task digital image including a plurality of colored pixels that differ from the initial digital image; Including, wherein the method comprises repeating steps ii) to iv) until the colored pixels of the mining digital image and the task digital image are found to be identical; In each case of step ii), a different mining printer control configuration is selected, and the mining printer control configuration for which the mining digital image and the task digital image are found to be identical, at least within a tolerance, is used as a proof-of-work for generating and validating blocks of the blockchain.

[0106] "Embodiment 2" 2. The method of embodiment 1, wherein solving the cryptographic puzzle includes finding a number that produces a cryptographic hash value having a defined number of leading digits.

[0107] "Embodiment 3" 3. The method of embodiment 1 or 2, wherein the preceding numbers are identical.

[0108] "Embodiment 4" The method according to any one of embodiments 1 to 3, wherein the preceding digit is zero.

[0109] "Embodiment 5" The method according to any one of embodiments 1 to 4, wherein the cryptographic hash value comprises a hexadecimal number.

[0110] "Embodiment 6" 6. The method of embodiment 4 or 5, wherein solving the cryptographic puzzle includes finding a hexadecimal number that produces a cryptographic hash value having a defined number of leading hexadecimal digits.

[0111] "Embodiment 7" 7. The method according to any one of embodiments 4 to 6, wherein the cryptographic hash value is generated using at least one hash function having as input the block number of the block, the data stored in the block, and the cryptographic hash of the previous block.

[0112] "Embodiment 8" 8. The method of embodiment 7, wherein the hash function is at least one secure hash function SHA-2 selected from the group consisting of SHA-224, SHA-256, SHA-384, SHA-512, SHA-512 / 224, SHA-512 / 256.

[0113] "Embodiment 9" A method according to any one of embodiments 4 to 8, wherein the method comprises applying the found numbers as mining printer control settings and checking whether one of the mining control settings transfers the initial digital image to the task digital image.

[0114] "Embodiment 10" The method of any one of embodiments 1 to 9, wherein the block includes a header containing information about a block version number, a cryptographic hash of the previous block header, a cryptographic hash of the block, a time, bits, and a nonce, the nonce being a mining printer control setting found in the transfer of the initial digital image to the task digital image, and the bits defining the number of pixels in the initial digital image and / or the number of pixels in the task digital image.

[0115] 『Embodiment 11』 A method according to any one of embodiments 1 to 10, wherein the mining printer control settings found to transfer the initial digital image to the task digital image are used to generate a number that is applied as a nonce to generate and verify blocks of the blockchain, and the size of the nonce is set prior to printing by information defining the color intensity of each color in the color space used for printing.

[0116] 『Embodiment 12』 12. The method of claim 11, wherein the size of the nonce is 4 bytes to define the intensity of a color in a color space ranging from 0 to 255, the intensity being represented by two hexadecimal digits for each pigment color.

[0117] 『Embodiment 13』 13. The method of any one of claims 1 to 12, further comprising generating an initial digital image by converting at least a portion of a cryptographic hash of a previous block header into color values ​​of colored pixels.

[0118] 『Embodiment 14』 14. The method of claim 13, wherein generating the initial digital image comprises converting hexadecimal digits of a cryptographic hash value of a previous block header into RGB colors of significant optical difference.

[0119] 『Embodiment 15』 15. The method of embodiment 13 or 14, wherein a cryptographic hash value of a previous block header is used to define the size and / or shape of pixels in the initial digital image before printing.

[0120] 『Embodiment 16』 A method according to any one of embodiments 13 to 15, wherein the method further comprises generating a task digital image by converting at least one portion of a cryptographic hash value other than the one used to generate the initial digital image into at least one color value of a colored pixel, and / or by using at least one random algorithm, and / or by converting digital information of transactions of a block into a color value.

[0121] 『Embodiment 17』 17. The method according to any one of the preceding embodiments, wherein the comparison of the colored pixels of the mining digital image and the task digital image is performed on a pixel-by-pixel basis.

[0122] 『Embodiment 18』 A method according to any one of embodiments 1 to 17, wherein the comparison of the color pixels of the mining digital image and the task digital image is performed after grouping the color pixels of the mining digital image or / and the task digital image by pixelation.

[0123] 『Embodiment 19』 19. The method of embodiment 18, comprising determining a color code of the pixelated mining digital image by converting colored pixels into numbers, and comparing the colored pixels of the mining digital image and the task digital image comprises comparing the color codes of the mining digital image and the task digital image.

[0124] 『Embodiment 20』 A method according to any one of the preceding embodiments, wherein the mining digital image and the task digital image are considered to be identical within a pixel colour error tolerance of ±30% for each colour of pixel, preferably ±10% for each colour of pixel, more preferably ±3% for each colour of pixel, and / or the mining digital image and the task digital image are considered to be identical within an overall error tolerance of 10% of deviant pixels, preferably 5% of deviant pixels, more preferably 1% of deviant pixels.

[0125] 『Embodiment 21』 A computer program comprising instructions for causing the processors to carry out a method according to any one of the preceding embodiments referring to the methods, when the program is executed by one or more processors.

[0126] 『Embodiment 22』 A computer-readable storage medium comprising instructions that, when executed by one or more processors, cause the processors to perform a method according to any one of the preceding embodiments referring to methods.

[0127] 『Embodiment 23』 A non-transient computer-readable medium comprising instructions that, when executed by one or more processors, cause the processors to perform a method according to any one of the preceding embodiments referring to the methods.

[0128] 『Embodiment 24』 A blockchain based on a digital image, the blockchain comprising a plurality of linked blocks, the blockchain being generated using a method for proof-of-work for generating and validating blocks of the blockchain as described in any one of the preceding embodiments relating to a method for proof-of-work for generating and validating blocks of the blockchain.

[0129] 『Embodiment 25』 Use of the computer-implemented method of any one of the preceding embodiments for a computer-implemented method for proof-of-work to generate and verify blocks of a blockchain for one or more purposes of mining for trading cryptocurrencies, secure processing of transactions in the fields of non-fungible tokens, smart contracts, financial services, healthcare, personal identification, cryptocurrencies, supply chains, and secure labels. [Brief description of the drawings]

[0130] Further optional features and embodiments are disclosed in more detail in the description of the following embodiments, preferably in conjunction with the dependent claims, where each optional feature may be realized in an isolated manner as well as in any possible combination as understood by a person skilled in the art. The scope of the present invention is not limited by the preferred embodiments. The embodiments are illustrated diagrammatically in the figures, where identical reference numbers in these figures represent identical or functionally equivalent elements.

[0131] On the diagram: [Figure 1] FIG. 1 illustrates one embodiment of a proof-of-work method according to the present invention.

[0132] Detailed Description of the Preferred Embodiments 1 illustrates one embodiment of a computer-implemented proof-of-work method for generating and validating blocks of a blockchain using at least one printing device configured to generate at least one digital image in response to printer control settings.

[0133] Generating a block may include adding and / or generating and / or creating a new block in the blockchain. Proof of Work may be a consensus process to ensure the creation of a new block in the blockchain. Before a block can be added to the blockchain, the information it contains must be "validated" by a network built on blockchain technology (also called a blockchain network). This may be done by solving a cryptographic puzzle, creating a so-called hash. The process of finding a solution is usually called "mining" or the "mining process". The nodes of the network may check if the found solution is correct. If the nodes confirm its validity, the block is considered valid and can be added to the blockchain.

[0134] A block may be a component or element of a blockchain. A blockchain can be defined as a chain of blocks that can hold certain records, and the blocks are linked together using cryptographic principles. For further details, see Eshani et al, "A study on the issue of blockchain's energy consumption", Chapter 2, DOI: 10.1007 / 978-981-15-0361-0_5 or en.wikipedia.org / wiki / Blockchain. Each block may contain transaction data. Blocks may be linked by including a hash value of the previous block. Each block may contain a cryptographic hash value of the previous block. Each block may further contain a timestamp. A blockchain may contain multiple linked blocks.

[0135] A block may include a header that contains several fields. In particular, the header includes information about the block version number, a cryptographic hash of the previous block header, a cryptographic hash based on all transactions in the block, time, bits, and a nonce. The structure of a block may be similar to the Bitcoin block architecture, e.g., as described in en.bitcoin.it / wiki / Block_hashing_algorithm. The block header may include the following fields:

[0136] [Table 3]

[0137] The fields block version number, also denoted as "Version", the cryptographic hash of the previous block header, also denoted as "hashPrevBlock", the cryptographic hash based on all transactions in the block, also denoted as "hashMerkleRoot", and "Time" may be generated in the same manner as in Bitcoin and may retain the same meaning. The time may be a timestamp as the number of seconds since 1970-01-01T00:00 UTC. This method may allow for time alignment with the transaction protocol of each block; however, other times are also possible.

[0138] The "bits" may define the number of pixels of the initial digital image and / or the number of pixels of the task digital image. The field "bits", e.g. 32-bit "bits", may be used to define the number of pixels of the task digital image 114. For example, the first 16 bits may be used to define the number of pixels of the initial digital image 116 to be printed. The second 16 bits may be used to define the number of pixels of the task digital image 114. The field "bits" may define the mining difficulty. The field "bits" may be used to address the difficulty and / or printing time depending on the number of pixels per each printing and scanning iteration. The more pixels printed, the longer the printing time and the longer the iterations. Thus, the field "bits" may be used differently as for Bitcoin.

[0139] The method may be implemented in whole or in part using a data processing means, such as a data processing means including at least one processor. The data processing means may include at least one computer and / or at least one network of computers. The computer may further include one or more further components, such as at least one of a data storage device, an electronic interface, or a human machine interface.

[0140] The printing device may be or include at least one device configured to apply, e.g. print, at least one material on at least one printing surface or substrate, in particular in a pattern, according to printer control settings. In particular, the printing device may include one or more of the following: a drum, such as an image drum; a conveyor, such as a transport belt; a laser; a lens system, such as a lens system including at least one mirror, e.g. a rotatable mirror; a cleaning element, e.g. a cleaning roll, scraper or similar means for cleaning the drum or conveyor; a cassette, e.g. a cassette; at least one transport element, such as a roller and / or conveyor, for feeding, transporting and / or discharging the substrate, in particular paper, into and / or from the printing device; a printer control unit configured to control the printing device. In particular, the material is printed on the surface of a drum, such as an image drum, or on a conveyor, such as a transfer belt. For example, the printing device may include a cassette for storing one or more of the substrates, such as a paper cassette; at least one transport element, such as a roller and / or a conveyor, for example for feeding, transporting and / or discharging the substrate, in particular the paper, into, into and / or out of the printing device. The printing device may include at least one pigment collector configured to collect the pigment from the transfer belt. The printing device may include at least one suction mechanism for sucking the pigment from the transfer belt, for example into the pigment collector. Other embodiments for transferring the pigment from the transfer belt to the pigment collector may be feasible, for example without using a suction mechanism. The printing device may include at least one, for example further, suction mechanism for transferring the collected pigment from the pigment collector out of the printing device. This makes it possible to ensure a 24-hour-7-day-week continuous operation of the printing device and to avoid manually emptying the pigment collector when it is filled with pigment. The printing device may comprise at least one material reservoir configured to supply the pigment for printing. The printing device may include at least one dosing mechanism. The dosing mechanism may be configured to transport pigment from a material reservoir for printing, for example into a printing device.This ensures 24-hour-7-day-week continuous operation of the printing device and avoids manual refilling of the pigment reservoir in the printing device when the pigment reservoir runs out of pigment.

[0141] The method includes (step i) (reference numeral 110) determining a number of digit sequences by solving at least one cryptographic puzzle, which may be potential mining printer control settings 112 for transferring and / or generating a task digital image 114 from an initial digital image 116.

[0142] The printer control settings may be printer control information including a number of parameters for controlling at least one function of the printing device. For example, the printer control settings may include a character string of a predefined length. The printer control settings may include at least one item of blending information, which is outlined in more detail below. Thus, typically, the printing device may be configured to generate text and / or images on at least one printing surface according to a printer control setting, such as one or more of a character string, a bitmap image, a vector image, a computer program, such as those provided in at least one printer control language. In particular, the printing device, and in particular at least one function of the printing device, may be controllable via at least one printer control language, such as one or more page description languages ​​(PDLs), printer command languages ​​(PCLs), PostScript, XML Paper Specification, etc. The mining printer control settings 112 may be printer control settings that are envisioned to be used to transfer and / or generate the task digital image 114 from the initial digital image 116.

[0143] The determination of the number strings, and in particular the determination of the number of potential mining printer control settings 112, may be performed by digital mining, for example, by solving at least one cryptographic puzzle, as is done for Bitcoin mining. The cryptographic puzzle may be any mathematical task with a defined difficulty. Solving the cryptographic puzzle may include finding numbers that generate a cryptographic hash value (also written hash value) with a defined number of leading digits. For example, the digits are identical. The input for the cryptographic puzzle may be the transactions in a block. The difficulty, which controls the average time to generate a block, may be adjusted depending on the computational power of the network of mining computers involved. The number of leading digits of the hash value may be fixedly defined, such as set to a number, and / or may be automatically defined, such as using at least one difficulty algorithm. The latter may include redefining and / or adjusting the number of leading digits, such as after a defined number of generating blocks. For example, the number of leading digits may be redefined and / or adjusted every 2016 blocks. The number of leading digits may be redefined and / or adjusted depending on the average time to generate a block, e.g., 10 minutes. The definition of the difficulty is depicted in FIG. 1 with reference numeral 113. The digits may be a symbol or a group of symbols representing a digit, e.g., a string of digits, a hexadecimal number, etc. In particular, the digits are potential nonces. One of the found nonces may be a printer control setting configured to transfer the initial digital image to the task digital image. In particular, one of the nonces may be a mining printer control setting 112 that transfers the initial digital image 116 to the task digital image 114, in particular after one or more of printing, scanning, and pixelating. For example, the cryptographic hash value includes hexadecimal numbers. Solving the cryptographic puzzle may include finding a hexadecimal number that generates a cryptographic hash value with a defined number of leading hexadecimal numbers, e.g., 10 leading zeros.For example, step i) 110 may involve finding a nonce that generates a predefined hash value, for example a number of "zeros", by solving a cryptographic puzzle, which is appended to the hexadecimal digits of the block's header.

[0144] The cryptographic hash value may be generated using at least one hash function with the block number of the block, the data stored in the block, and the cryptographic hash of the previous block as input. The hash function may be any function that can be used to map data of any size to a fixed size value. The value returned by the hash function is called the hash value. The cryptographic hash value may be a fixed length number that uniquely represents the data. For example, the cryptographic hash value may include a hexadecimal number. The data may be information and / or a machine-readable signal or symbol representative of the information. The data may specifically be or include one or both of digital data and analog data. For example, the hash function may be at least one secure hash function SHA-2 selected from the group consisting of SHA-224, SHA-256, SHA-384, SHA-512, SHA-512 / 224, SHA-512 / 256. For example, the version number of the current block, the data stored in the block (including the nonce), and the hash value of the previous block may be used as input for the hash function.

[0145] The method further includes, in step ii) 118, selecting one of the determined number strings as the mining printer control setting 112. In particular, the method includes applying the found number as the mining printer control setting 112 and checking whether one of the mining control settings 112 transfers the initial digital image 116 to the task digital image 114. The mining printer control setting may be selected iteratively. The mining printer control setting 112 found to transfer the initial digital image 116 to the task digital image 114 is used to generate a number that is applied as a nonce to generate and verify blocks of the blockchain.

[0146] The method further includes, in step iii), printing 120 at least one initial digital image 116 comprising a plurality of colored pixels using a printing device having selected mining printer control settings 112, and scanning 120 the printed image using at least one scanning device, thereby generating a mined digital image 122 having a plurality of colored pixels different from the initial digital image 116.

[0147] The size of the nonce may be set before printing. For example, the size of the nonce may be set by information defining the color intensity of each color in a color space used for printing. For example, the intensity of each color in a color space, e.g., a CMYK color space, may vary in the range of 0 to 255. Thus, the structure of the nonce may be {CC-MM-YY-KK}. For example, the size of the nonce is 4 bytes to define the color intensity of a color space ranging from 0 to 255. Specifically, to define the intensity of four colors in a color space ranging from 0 to 255, the size of the nonce is 4 bytes. The intensity may be represented by two hexadecimal digits for each color.

[0148] The method may further include generating an initial digital image 116 by converting at least a portion of the cryptographic hash of the previous block header into color values ​​of colored pixels. Generating at least one initial digital image 116 may include determining colors of pixels of the initial digital image 116. The initial digital image 116 may be any digital image used as a starting point for mining. The initial digital image 116 may be generated by converting at least a portion of the cryptographic hash value of the previous block header into color values ​​of colored pixels of the initial digital image 116. For example, generating the initial digital image 116 may include converting at least a portion of the hexadecimal value of the cryptographic hash value of the previous block header into RGB color for printing the initial digital image on a substrate using pigment particles according to a further color space, for example, the CMYK color space. For example, the conversion from hexadecimal to color value may be performed using at least one mathematical algorithm and / or at least one predetermined relationship, such as a look-up table, e.g., as described in www.rapidtables.com / convert / color / hex-to-rgb.html, or in “The Image-Interface: Graphical Supports for Visual Information”, Everardo Reyes-Garcia, John Wiley & Sons, 2017, ISBN 978-1-1194-7497-5.

[0149] The generation of the initial digital image 116 may include selecting a hexadecimal number from a cryptographic hash value of a previous block header. For example, the cryptographic hash value may be used to include in the header of the block. For example, for a first pixel of the initial digital image 116, the first six hexadecimal digits may be selected and converted to an RGB color. For further pixels of the initial digital image 116, the next six digits may be subsequently selected and converted to an RGB color. However, other embodiments for selecting a hexadecimal number from the cryptographic hash are possible. For example, the cryptographic hash value of the previous block header may be processed, for example by sorting and / or at least one further mathematical algorithm. For example, the method may include generating, for each pixel of the initial digital image 116, a table including rows and columns. Each row may include a different processed version of the initial cryptographic hash value. For example, for a first pixel of the initial digital image 116, the first six rows of numbers in the first column may be selected. For further pixels of the initial digital image 116, the next row and / or column may be subsequently selected.

[0150] The generation of the initial digital image 116 may include converting the hexadecimal value of the cryptographic hash value of the previous block header into RGB colors of optical significance. For example, the conversion from the hexadecimal value of the cryptographic hash value to RGB colors of optical significance may be performed according to a predefined lookup table (exemplary for a 4-bit color space):

[0151] [Table 4]

[0152] The RGB color space may be a 24-bit color space. The RGB color palette is 8 ) 3 In order to achieve significant optical differentiation, only two hexadecimal digits may be used to define each RGB color.

[0153] The cryptographic hash value of the previous block header may be used to define the size and / or shape of a pixel of the initial digital image 116 prior to printing on the substrate. The hexadecimal value of the cryptographic hash value of the previous block header is preferably used to define the amount of color dots per pixel. The hexadecimal value of the cryptographic hash value of the previous block header may be used to define the amount of color dots per pixel. The method may include generating a table including a row and a column for each pixel of the initial digital image 116. Each row may include a different processed version of the initial cryptographic hash value. For example, the size of a first pixel of the initial digital image 116 may be defined by the seventh row of the first column. For further pixels of the initial digital image, the next seventh row and / or column may be selected, and so on. The shape of the pixel may be defined by a portion of the cryptographic hash value. For example, the seventh row may also be used for the shape and / or another row may be used to define the shape. For example, a pixel may be circular for values ​​between 0 and 4, triangular for values ​​between 5 and 8, square for values ​​between 9 and B, and diamond for values ​​between C and F.

[0154] The task digital image 114 may be any digital image used as a cryptography puzzle. The task digital image 114 includes a number of different colored pixels than the initial digital image 116. The colored pixels of the task digital image 114 may have the same or different color values. The colored pixels of the initial digital image 116 and / or the task digital image 114 may be colored pixels in the RGB color space.

[0155] The task digital image 114 may be generated by converting at least a portion of the cryptographic hash value of the previous block header other than that used for generating the initial digital image 116 into at least one color value of a colored pixel. With regard to converting at least a portion of the cryptographic hash value into a color value of a pixel of the task digital image 114, reference is made to the generation of the initial digital image 114. However, a portion of the cryptographic hash value other than that of the initial digital image may be used for the task digital image 116. However, other color spaces may also be possible. For example, for mining, the RGB color of the task digital image 114 may first be automatically defined, for this purpose using, for example, the last 24 bits of the cryptographic hash of the previous block.

[0156] Additionally or alternatively, the task digital image 114 may be generated using at least one random algorithm. Such random algorithms are generally known to those skilled in the art. The random numbers, such as hexadecimal numbers, generated by the random algorithm may be converted to color values. The conversion from hexadecimal numbers to color values ​​may be performed using at least one mathematical algorithm and / or at least one predefined relationship, such as a lookup table, as described, for example, in “Improving Image Performance by Using Color Lookup Tables, Adobe developer support, Technical Note #5121, 31 March 1992 or https: / / www.rgbtohex.net / hextorgb / ”.

[0157] Additionally or alternatively, the task digital image 114 may be provided by converting digital information of a transaction of a block, such as the block to be added or the previous block, into color values, e.g., RGB or CMYK colors. The transaction may include financial transactions, such as payments, licenses, orders, invoices, and / or logistics transactions, such as deliveries, storage records, travel records, and / or planning transactions, and / or tax returns, and / or contracts, and / or personal health information, etc. The digital information of the transaction may be data describing at least one transaction, also referred to as transaction data. The transaction data may include information regarding one or more of the following: time of transaction, value of transaction, text of transaction, digital image of transaction, text of transaction, digital image of transaction, etc. The transaction data may be provided in binary format.

[0158] The mining proposed by the present invention relates to finding a mining printer control setting 112 among a plurality of mining printer control settings 112 that transfers an initial digital image 116 to a task digital image 114. Miners (miners) compete to first find a plurality of potential mining printer control settings by solving a cryptographic puzzle, and then identify the number of the mining printer control setting 112 among the plurality of potential mining printer control settings 112 that converts the initial digital image to the task digital image. The miner who first finds the mining printer control setting 112 that converts the initial digital image 116 to the task digital image 114 may be awarded. Other miners may check the mining printer control settings 112.

[0159] The mined digital image 122 has a number of different colored pixels than the initial digital image 116. The colored pixels of the mined digital image 122 may be colored pixels in CMYK color space or RGB color space. The mined digital image 122 may be a digital image generated by printing the initial digital image 116 with a printing device by blending and / or mixing pigments with selected mining printer control settings 112 and scanning the printed image with at least one scanning device. Printing may include printing on a substrate. Blending may include at least one step of mixing pigments in a prescribed manner, thereby creating a blend. The printing device may be configured for use as a blending device. In particular, the printing device is configured to receive at least one item of blending information and generate a digital image. Regarding embodiments of the printing device, the scanning device and the pigments, reference is made to WO 2021 / 001147, the entire content of which is hereby incorporated by reference.

[0160] This method may include a combination of digital proof-of-work and blockchain technology, first solving a cryptographic puzzle by finding potential nonces that, when added to the hexadecimal digits of the block header, produce a specific hash value, for example a number of "zeros", and in a second step applying these nonces as mining printer control settings to prove whether the mining printer control settings are capable of transferring the initial digital image 116 to the task digital image 114, especially after printing and pixelation. The computer does not need to be faster than this period, since this physical step of printing and scanning is the bottleneck in the processing time. Therefore, the printer speed, not the computing power, governs the hash frequency.

[0161] The method further includes, in step iv) 124, comparing, using at least one processing device, the colored pixels of the mining digital image 122 and the task digital image 114. The method includes repeating steps ii) through iv) until the colored pixels of the mining digital image 122 and the task digital image 114 are found to be identical. In each case, in step ii), a different mining printer control setting 112 is selected. The mining printer control setting 112 for which the mining digital image 122 and the task digital image 114 are found to be identical, at least within a tolerance, is used as proof-of-work for generating and verifying blocks of the blockchain.

[0162] The comparison of color pixels of the mining digital image 122 and the task digital image 114 may be performed pixel by pixel. The comparison of colored pixels of the mining digital image 122 and the task digital image 114 may be performed after grouping colored pixels of the mining digital image or / and the task digital image by pixelation. In particular, the method may comprise pixelating the mining digital image 122 and / or the task digital image 114. The pixelation may comprise dividing the mining digital image 122 and / or the task digital image 114 into pixels, in particular into a predefined number of pixels. For example, the predefined number of pixels of the mining digital image 122 may correspond to the number of pixels of the task digital image 114. For example, the predefined number of pixels may depend on the difficulty level of mining.

[0163] The method may include determining a color code of the pixelated mined digital image 122 by converting the colored pixels, for example, into a hexadecimal or binary number. For example, the conversion of color values ​​into hexadecimal numbers may be performed using at least one mathematical algorithm and / or at least one pre-determined relationship, such as a look-up table (for example, as described at www.farben-umrechnen.de or in "The Image-Interface: Graphical Supports for Visual Information", Everardo Reyes-Garcia, John Wiley & Sons, 2017, ISBN 978-1-1194-7497-5). The hexadecimal number may be further converted to a binary code by using at least one mathematical algorithm and / or at least one predetermined relationship, such as a lookup table, as described, for example, in “Improving Image Performance by Using Color Lookup Tables, Adobe developer support, Technical Note #5121, 31 March 1992” or at https: / / www.rgbtohex.net / hextorgb / .

[0164] The comparison of colored pixels of the mined digital image 122 and the task digital image 114 may include comparing color codes of the pixelated mined digital image 122 and the task digital image 114. The comparison may include determining whether the mined digital image 122 and the task digital image 114 are identical within at least a predefined pixel color tolerance. The mined digital image 122 and the task digital image 114 may be considered identical within a pixel color error tolerance of ±30% for each color of pixel, preferably ±10% for each color of pixel, and more preferably ±3% for each color of pixel. Additionally or alternatively, an overall match of the mined digital image 122 and the task digital image 114 may be determined. The mined digital image 122 and the task digital image 114 may be considered identical within an overall error tolerance of 10% of deviant pixels, preferably 5% of deviant pixels, and more preferably 1% of deviant pixels. The comparison may be performed by a processing device of the node, for example a printing device.

[0165] The method may include determining, by the nodes of the network, whether the mining digital image 122 and the task digital image 114 are identical, at least within a predefined tolerance. The pixel color error tolerance of the miner performing the method may be tighter compared to the predefined tolerance of the other nodes. This may ensure that each node can verify that the discovered mining printer control setting 112 is correct within the tolerance, even if the printing device has a deviating accuracy. Other miners may generate the same mining digital image 122, thus verifying the nonce. All mining printer control settings 112 that are outside the error tolerance are rejected. All mining printer control settings 112 that are within the error tolerance are accepted. Thus, whoever finds it first can add the block to the chain and get a reward in crypto coins. The reward based on mined cryptocurrency units and transaction fees may be the same as for Bitcoin mining, but with printer capacity instead of computing power and pigments instead of electricity. The printing device may be implemented in the blockchain network in the same way as the mining computer, and in particular may perform the same functions.

[0166] The method may include at least one calibration step: a number of pre-specified color fields, such as the primaries of the color space used, may be provided and printed together with the mined digital image 122, which may allow for calibration of the scanning result.

[0167] The method may include generating a header for the subsequent block that includes information about a block version number, a cryptographic hash of the previous block header, a cryptographic hash based on all transactions in the block, a time, a bit, and a nonce. The nonce may be the mining printer control settings 112 discovered for transferring the initial digital image 116 to the task digital image 114.

[0168] Reference Number List 110 Step i) 112 Mining Printer Control Settings 113 Difficulty 114 Task Digital Image 116 Early Digital Images 118 Step ii) 120 Step iii) 122 Mining Digital Images 124 Step iv)

Claims

1. A computer-implemented method for proof of work for generating and validating blocks of a blockchain using at least one printing device, the printing device configured to generate at least one digital image in response to printer control settings, the method comprising the steps of: i) (110) determining a plurality of number sequences by solving at least one cryptographic puzzle; ii) (118) selecting one of the determined plurality of digit strings as a mining printer control setting (112); iii) (120) printing at least one initial digital image (116) including a plurality of colored pixels using a printing device having selected mining printer control settings (112) and scanning the printed image using at least one scanning device, thereby generating a mined digital image (122) having a plurality of colored pixels different from the initial digital image (116); iv) (124) using at least one processing device, comparing colored pixels of the mined digital image (122) and the task digital image (114), the task digital image (114) including a number of colored pixels that differ from the initial digital image (116); Including, wherein the method comprises repeating steps ii) (118) to iv) (124) until the colored pixels of the mining digital image (122) and the task digital image (114) are found to be identical; In each instance of step ii) (118), a different mining printer control setting (112) is selected, and the mining printer control setting (112) for which the mining digital image (122) and the task digital image (114) are found to be identical, at least within a tolerance, is used as a proof of work for generating and verifying blocks of the blockchain.

2. The method of claim 1 , wherein solving the cryptographic puzzle comprises finding a number that produces a cryptographic hash value having a defined number of leading digits.

3. 3. The method of claim 2, wherein solving the cryptographic puzzle comprises finding a hexadecimal number that produces a cryptographic hash value having a defined number of leading hexadecimal digits.

4. 4. The method of claim 2 or 3, wherein the cryptographic hash value is generated using at least one hash function having as input the block number of the block, the data stored in the block and the cryptographic hash of the previous block.

5. 4. The method of claim 2 or 3, further comprising: applying the found number as mining printer control settings (112); and checking whether one of the mining control settings (112) transfers the initial digital image (116) to the task digital image (114).

6. 3. The method of claim 1 or 2, wherein the block includes a header containing information regarding a block version number, a cryptographic hash of a previous block header, a cryptographic hash of the block, a time, a bit, and a nonce, the nonce being a mining printer control setting found in the transfer of the initial digital image (116) to the task digital image (114), and the bit defining a number of pixels in the initial digital image (116) and / or a number of pixels in the task digital image (114).

7. 3. The method according to claim 1 or 2, wherein the mining printer control settings (112) found for transferring the initial digital image (116) to the task digital image (114) are used to generate a number to be applied as a nonce for generating and verifying blocks of the blockchain, the size of the nonce being set before printing by information defining the color intensity of each color in the color space used for printing.

8. 3. The method of claim 1 or 2, further comprising generating the initial digital image (116) by converting at least a portion of a cryptographic hash of a previous block header into color values ​​of colored pixels.

9. 9. The method of claim 8, further comprising generating the task digital image (114) by converting at least a portion of a cryptographic hash value other than that used to generate the initial digital image (116) into at least one color value of a colored pixel, and / or by using at least one random algorithm, and / or by converting digital information of the transactions of the block with color values.

10. 3. The method of claim 1 or 2, wherein the comparison of colored pixels of the mining digital image (122) and the task digital image (114) is performed after grouping the colored pixels of the mining digital image (122) or / and the task digital image (114) by pixelation, and the method comprises determining a color code of the pixelated mining digital image (122) by converting the colored pixels into numbers, and the comparison of colored pixels of the mining digital image (122) and the task digital image (114) comprises comparing the color codes of the mining digital image (122) and the task digital image (114).

11. 3. The method of claim 1 or 2, wherein the mining digital image (122) and the task digital image (114) are considered to be identical within a pixel color error tolerance of ±30% for each pixel color, preferably ±10% for each pixel color, more preferably ±3% for each pixel color, and / or the mining digital image (122) and the task digital image (114) are considered to be identical within an overall error tolerance of 10% of deviant pixels, preferably 5% of deviant pixels, more preferably 1% of deviant pixels.

12. A computer program comprising instructions which, when the program is executed by one or more processors, cause the processors to carry out the method according to claim 1 or 2.

13. A non-transitory computer readable medium comprising instructions that, when executed by one or more processors, cause the processors to perform the method of claim 1 or 2.

14. 3. A blockchain based on a digital image, the blockchain comprising a plurality of linked blocks, the blockchain being generated using a method for proof of work for generating and verifying blocks of a blockchain as claimed in claim 1 or 2, which relates to a method for proof of work for generating and verifying blocks of a blockchain.

15. Use of the computer-implemented method for proof of work according to claim 1 or 2 for generating and verifying blocks of a blockchain for one or more purposes of secure processing of transactions in the fields of mining, non-fungible tokens, smart contracts, financial services, healthcare, personal identification, cryptocurrencies, supply chains, secure labels for trading cryptocurrencies.

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