Information code, code generation method, and code reading method

Abstract

The invention relates to an information code, a code generation method, and a code reading method. The information code (CQ2) is formed by combining a public code (Cd1) and a hiding code (Cd2), which record information by means of the two-dimensional arrangement of the plurality of cells (Ce). The information code (CQ2) includes, in addition to a white unit (Cww) and a black unit (Cbw), a medium white unit (Cwc) and a medium black unit (Cbw). A middle white region surrounded by the outer black region is formed in the middle white cell (Cwc). A middle black region surrounded by the outer white region is formed in the middle black cell (Cbc).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on Japanese Patent Application No. 2022-83973 filed in Japan on May 23, 2022, and the contents of the basic application are cited in their entirety by reference. Technical Field

[0003] The disclosure according to this specification relates to a technology of information codes for recording information. Background Art

[0004] Patent Document 1 describes an information code that combines two two-dimensional codes. In addition to black cells and white cells, the information code also includes light gray cells and dark gray cells. By arranging these four types of cells in two dimensions, the information of the two two-dimensional codes can be read from the information code.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-196762

[0006] In the information code of Patent Document 1, the shade of the gray cell, which is an intermediate color, is easily changed due to the influence of the light irradiating the information code. Therefore, for example, when a shadow is generated only in a part of the information code, it is difficult to distinguish between the light gray cell and the dark gray cell, and the code reading is likely to fail. Summary of the invention

[0007] An object of the present disclosure is to provide an information code capable of reducing reading failures, and a method for generating and reading such an information code.

[0008] In order to achieve the above-mentioned purpose, a disclosed method is an information code, which is an information code synthesized by a first code and a second code for recording information through a two-dimensional arrangement of multiple units, including: a light unit; a dark unit; a medium-light unit, in which a medium-light area is formed in the unit and surrounded by an outer dark area; and a medium-dark unit, in which a medium-dark area is formed in the unit and surrounded by an outer light area.

[0009] Another disclosed method is a code generation method, which includes the following steps in the processing implemented by at least one processing unit: preparing a first code and a second code that record information by a two-dimensional arrangement of multiple units; and generating an information code by synthesizing the first code and the second code, in the step of synthesizing the first code and the second code: setting the unit at the position where the first code and the second code are both light units as a light unit; setting the unit at the position where the first code and the second code are both dark units as a dark unit; setting the unit at the position where the first code is a light unit and the second code is a dark unit as a medium light unit with a medium light area surrounded by an outer dark area; and setting the unit at the position where the first code is a dark unit and the second code is a light unit as a medium dark unit with a medium dark area surrounded by an outer light area.

[0010] Another disclosed method is a code reading method, which is a code reading method that reads a second code from an information code that is synthesized by a first code and a second code that record information through a two-dimensional arrangement of multiple units, and the processing implemented by at least one processing unit includes the following steps: making a medium-light color unit having a medium-light color area surrounded by an outer dark color area in a unit of the information code become a dark color unit; and making a medium-dark color unit having a medium-dark color area surrounded by an outer bright color area in a unit of the information code become a light color unit.

[0011] In these methods, in addition to the light color unit and the dark color unit, a medium light color unit having a medium light color area surrounded by an outer dark color area and a medium dark color unit having a medium dark color area surrounded by an outer light color area are used. Therefore, even if the light irradiating the information code is affected, it is not easy to cause a situation where it becomes difficult to distinguish between the medium light color unit and the medium dark color unit. As a result, the failure of code reading can be reduced.

[0012] In addition, the reference numerals in parentheses in the claims are merely an example of the correspondence relationship with the specific configurations in the embodiments described later, and do not limit the technical scope at all. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 2 is a diagram showing information codes according to the first embodiment of the present disclosure.

[0014] Figure 2 This figure shows an overall picture when the traceability system is used together with the existing distribution management system.

[0015] Figure 3 This is a diagram for explaining the rules for synthesizing the public code and the concealed code.

[0016] Figure 4This is a flowchart showing the details of the code generation process performed by the history management server.

[0017] Figure 5 This is a flowchart showing the details of the code reading process performed by a code scanner or the like.

[0018] Figure 6 This is a diagram showing the details of image processing for converting medium white cells and medium black cells into black cells and white cells.

[0019] Figure 7 It is a diagram showing a middle white cell and a middle black cell according to Modification Example 1.

[0020] Figure 8 It is a diagram showing a middle white cell and a middle black cell according to Modification Example 2.

[0021] Fig. 9 It is a diagram showing a middle white cell and a middle black cell according to Modification Example 3.

[0022] Fig.10 It is a diagram showing a middle white cell and a middle black cell according to Modification Example 4. DETAILED DESCRIPTION

[0023] Generated by synthesizing two QR codes Figure 1 The information code CQ2 according to one embodiment of the present disclosure is shown. The two-dimensional code that forms the basis of the information code CQ2 is, for example, a QR code (registered trademark), etc., which records information by a two-dimensional arrangement of multiple units Ce. The information code CQ2 is printed on a paper medium, etc., and is used in the state of a code printing medium such as a label, a sticker, and a tag. The information code CQ2 can also be displayed on a display device such as a display and electronic paper.

[0024] The information code CQ2 of this embodiment is generated by synthesizing the public code Cd1 and the concealment code Cd2. Figure 2 ) reads the information code CQ2, the information code CQ2 is recognized as the public code Cd1. In this case, the information recorded in the public code Cd1 (hereinafter referred to as the public information) is read. On the other hand, by using the code scanner 23 described later (refer to Figure 2 ) etc., can read the concealment code Cd2. In this case, the information recorded in the concealment code Cd2 (hereinafter referred to as concealed information) is read out.

[0025] exist Figure 2The circulation management system 110 and the traceability system 120 shown both use the information code CQ2. The circulation management system 110 and the traceability system 120 are management systems for managing a supply chain SC constructed by including many traders TR. The supply chain SC is a connection between traders for delivering industrial products, agricultural products, and aquatic products to end users. As an example, in the supply chain SC for delivering agricultural products to consumers, farmers TR1, agricultural cooperatives TR2 as purchasing facilities, transporters TR3, and retailers TR4 are included in the traders TR.

[0026] The circulation management system 110 collects the transaction records of the transaction items between the traders TR using the public code Cd1. In other words, the public code Cd1 is a QR code used in the circulation management system 110. The circulation management system 110 is composed of an input terminal 11, a label printer 12, a code reader 13, and a system server 10. The input terminal 11, the label printer 12, and the code reader 13 are appropriately installed in the facilities of each trader TR. The input terminal 11, the label printer 12, and the code reader 13 are connected to the system server 10 installed in a data center or the like through a network.

[0027] The input terminal 11 is, for example, a personal computer or a tablet terminal. Basic information (hereinafter referred to as item information) of the transaction items supplied to the supply chain SC is input into the input terminal 11 in a prescribed format. For example, the item name, production location, production equipment, and producer are set as item information. The input terminal 11 transmits the item information of the transaction items shipped from the trader TR to the system server 10.

[0028] The label printer 12 is an output device for printing the disclosure code Cd1 on a paper medium. The label printer 12 is a black and white printer capable of only black and white printing. The paper medium printed with the disclosure code Cd1 is attached to the packaging or outer box of the shipped transaction item and circulated as an attachment to the transaction item.

[0029] The code reader 13 is a reading device that reads the disclosure code Cd1 to obtain the public information recorded in the disclosure code Cd1 . The code reader 13 obtains the public information recorded in the disclosure code Cd1 , and transmits the obtained public information to the system server 10 .

[0030] The system server 10 is a host node that can communicate with the input terminal 11, the label printer 12, and the code reader 13. The system server 10 registers the project information obtained from the input terminal 11 in the database. The system server 10 prepares public information associated with the project information and generates a public code Cd1 that records the public information. The system server 10 sends the image data of the generated public code Cd1 to the label printer 12, which is the source of the project information, as a process of issuing the public code Cd1. The issued public code Cd1 is circulated together with the transaction item. If it is read by the code reader 13 of another trader TR, the system server 10 accumulates the transaction record of the transaction item of the trader TR.

[0031] The traceability system 120 is used together with the circulation management system 110, and accumulates transaction records in the same manner as the circulation management system 110. In detail, the circulation management system 110 is equivalent to the old management system, and the traceability system 120 is equivalent to the new management system. The traceability system 120 does not actually change the existing circulation management system 110, but is used together with the circulation management system 110. In addition to the record generation function of accumulating transaction records, the traceability system 120 also has a record reference function of providing the accumulated transaction records for reference. In the traceability system 120, the blockchain technology is used in the management of transaction records for the purpose of preventing tampering of transaction records.

[0032] The traceability system 120 collects transaction records using the information code CQ2 based on the public code Cd1 issued by the system server 10. The traceability system 120 is composed of a code output device 22, a code scanner 23, and a history management server 20. In addition, the input terminal 11 and the label printer 12 of the circulation management system 110 are used in the traceability system 120. The code output device 22, the code scanner 23, and the input terminal 11 are connected to the history management server 20 set in a data center or the like through a network.

[0033] The code output device 22 is installed in the facility of the trader TR where the label printer 12 is installed. The code output device 22 is installed in the form of being inserted into the communication line between the system server 10 and the label printer 12, and obtains the data of the public code Cd1 sent from the system server 10 to the label printer 12. The code output device 22 sends the obtained data of the public code Cd1 to the history management server 20.

[0034] The code output device 22 receives data of the information code CQ2 generated based on the transmitted public code Cd1 from the history management server 20. The information code CQ2 also records the confidential information used in the traceability system 120. The code output device 22 sends the data of the information code CQ2 to the label printer 12 instead of the data of the public code Cd1. With the intervention of the code output device 22, the label printer 12 does not recognize the change (replacement) of the acquired code data, but prints the information code CQ2 on the paper medium. As a result, the code print medium printed with the information code CQ2 instead of the public code Cd1 is affixed to the transaction item and circulated together with the transaction item.

[0035] The code scanner 23 is a reading device that reads the confidential information added to the information code CQ2 separately from the public information. The confidential information is the information recorded in the information code CQ2. The code scanner 23 is a structure that scans the same object as the code reader 13, so it can also be physically integrated with the code reader 13. The code scanner 23 is composed of an imaging sensor in which CCD elements are arranged two-dimensionally, and a signal processing unit 41. The imaging sensor can read the information recorded in a plane with a higher resolution than the code reader 13. The imaging sensor outputs a captured image (hereinafter referred to as a code captured image) showing the information code CQ2 to the signal processing unit 41.

[0036] The signal processing unit 41 includes a storage unit storing a code reading program and the like, and a unit for executing a code reading process described later based on the code reading program (see Figure 5 ) processor and RAM. The signal processing unit 41 decodes the read signal (code captured image) of the imaging sensor according to the prescribed rules through code reading processing, and obtains the confidential information recorded in the information code CQ2. Based on the obtained confidential information, the signal processing unit 41 communicates with the history management server 20 to leave a transaction record.

[0037] In addition, a smartphone or tablet terminal having a camera function can be used as the code scanner 23. In such a system, a dedicated application corresponding to a code reading program is provided and installed in a smartphone or the like.

[0038] The history management server 20 is a host node that can communicate with the input terminal 11 in addition to the code output device 22 and the code scanner 23. The history management server 20 is a structure that is mainly composed of a computer having a processing unit 31, a RAM 32, a storage unit 33, an input / output interface, and a bus connecting them. The processing unit 31 is hardware for calculation processing combined with the RAM 32. The processing unit 31 performs various processes related to data management by accessing the RAM 32. The storage unit 33 stores a code generation program for causing the processing unit 31 to execute the code generation method according to the present disclosure as one of the management programs related to data management.

[0039] The record management server 20 acquires the item information sent from the input terminal 11 to the system server 10. Based on the acquisition of the item information, the record management server 20 generates a blockchain for storing the item information and the transaction record, and the blockchain is a blockchain associated with the transaction item. When the record management server 20 acquires a notification of the fact that the information code CQ2 has been read from the code scanner 23 of each trader TR, the transaction record of the trader TR of the notification source is accumulated in the blockchain associated with the transaction item.

[0040] Specifically, when the history management server 20 receives a notification from the code scanner 23, it generates a new block that stores the transaction records of the trader TR of the notification source. In addition to the current transaction records, the new block also contains a hash value calculated based on the previous block. The hash value is generated using a hash function such as SHA-256. The hash value is data that maintains a specified number of bits (for example, 256 bits) and reflects the project information and transaction records.

[0041] The history management server 20 performs a code generation process described later (see Figure 4 ), generates an information code CQ2 that records at least the above-mentioned hash value as confidential information. The history management server 20 issues the generated information code CQ2 to the code output device 22. Thus, the hash value reflecting the item information and the transaction record is recorded in the information code CQ2 and can be circulated together with the transaction item.

[0042] In addition, in the traceability system 120, a plurality of traders TR may continuously use one information code CQ2, or a new information code CQ2 may be issued for each trader TR. In the method of issuing a new information code CQ2 for each trader TR, a latest hash value reflecting the transaction record is generated based on the generation of the transaction record of each trader TR. The history management server 20 newly generates an information code CQ2 that records the latest hash value as confidential information, and provides the data of the new information code CQ2 to the label printer 12 set up at the facility of the trader TR who conducted the transaction. As a result, as the transaction of the item proceeds, the content (hash value) of the information code CQ2 is continuously updated to reflect the content of the transaction record so far. In addition, since the confidential information is the content based on the hash value, the data volume of the confidential information can be maintained constant even if the item is traded in the supply chain SC.

[0043] The history management server 20 can also issue a traceability code QRt. The traceability code QRt is a two-dimensional code such as a QR code attached to the final product FP supplied through the supply chain SC. The traceability code QRt enables consumers who have obtained the final product FP to confirm the transaction record. As an example, the traceability code QRt records a hash value calculated from the last block of the blockchain and an IP address or URL indicating a query destination for the transaction record.

[0044] The consumer of the final product FP can browse the transaction record of the final product FP by using the user terminal 50 such as a smartphone or a tablet terminal, for example, and using the traceability confirmation application. Specifically, when the user terminal 50 reads the traceability code QRt attached to the final product FP, it sends a reference request for the transaction record together with the hash value to the record management server 20 that is the inquiry destination. When the record management server 20 receives the reference request, it extracts the item information and the transaction record associated with the hash value and generates the provision data. The record management server 20 sends the generated provision data to the user terminal 50 that is the request source of the reference request. The consumer of the final product FP can confirm the history of the transaction record by using the traceability confirmation application and expanding the provision data received from the record management server 20.

[0045] Next, based on Figure 1 as well as Figure 3 The information code CQ2 will be further described in detail.

[0046] As described above, the information code CQ2 is generated by synthesizing the public code Cd1 and the concealment code Cd2 (see Figure 1). The public code Cd1 and the concealed code Cd2 record information by two-dimensional arrangement of white cells Cww and black cells Cbw, respectively. The public code Cd1 and the concealed code Cd2 are two-dimensional codes with the same number of cells (versions). Therefore, the information code CQ2 synthesized by the public code Cd1 and the concealed code Cd2 also becomes a two-dimensional code with the same number of cells as the public code Cd1 and the concealed code Cd2.

[0047] The information code CQ2 includes, in addition to the white cells Cww and the black cells Cbw, the middle white cells Cwc and the middle black cells Cbc. The information code CQ2 maintains both public information and private information by a two-dimensional arrangement of the white cells Cww, the black cells Cbw, the middle white cells Cwc and the middle black cells Cbc. The cells Ce of the information code CQ2 are determined based on the combination of the white cells Cww and the black cells Cbw of the public code Cd1 and the private code Cd2 (see Figure 3 ).

[0048] Specifically, the cell Ce at the position where both the public code Cd1 and the concealed code Cd2 are black cells Cbw is also a black cell Cbw in the information code CQ2. Similarly, the cell Ce at the position where both the public code Cd1 and the concealed code Cd2 are white cells Cww is also a white cell Cww in the information code CQ2. On the other hand, the cell Ce at the position where the public code Cd1 is black cell Cbw and the concealed code Cd2 is white cell Cww becomes a medium black cell Cbc. In addition, the cell Ce at the position where the public code Cd1 is white cell Cww and the concealed code Cd2 is black cell Cbw becomes a medium white cell Cwc.

[0049] In the middle white unit Cwc, a middle white region wc surrounded by an outer black region bs is formed. The shape of the middle white region wc is similar to that of the middle white unit Cwc, that is, a square or a rectangle. The middle white region wc is located at the center of the middle white unit Cwc and is concentrically arranged with the middle white unit Cwc. The outer black region bs surrounds the middle white region wc in the entire circumference.

[0050] In the middle black unit Cbc, a middle black region bc surrounded by an outer white region ws is formed. The shape of the middle black region bc is similar to that of the middle black unit Cbc, which is a square or a rectangle. The middle black region bc is located at the center of the middle black unit Cbc and is concentrically arranged with the middle black unit Cbc. The outer white region ws surrounds the middle black region bc on the entire circumference.

[0051] The sizes of the middle white region wc and the middle black region bc are the same. As an example, the length of one side of the middle white region wc and the middle black region bc is set to about 1 / 2 to 3 / 4 of the length of one side of the middle white unit Cwc and the middle black unit Cbc. The color of the middle white region wc and the outer white region ws is substantially the same as the color of the white unit Cww. Similarly, the color of the middle black region bc and the outer black region bs is substantially the same as the color of the black unit Cbw.

[0052] Here, the code reader 13 (see Figure 2 ) When reading the information code CQ2, scan the center of each unit Ce (refer to Figure 3 Dashed arrow). Therefore, the code reader 13 distinguishes the middle white cell Cwc as the white cell Cww, and the middle black cell Cbc as the black cell Cbw. As a result, the code reader 13 recognizes the information code CQ2 as a two-dimensional code that is substantially the same as the public code Cd1, and is able to read the public information. Here, in the QR code, the information is written in a Z shape from the cell Ce in the lower right. Therefore, a general code reader 13 that reads the QR code scans the cells Ce of the two columns together in a Z shape. Even with such a code reader 13, the center of each cell Ce is taken as the object of scanning, and the information code CQ2 is also recognized as a two-dimensional code that is the same as the public code Cd1.

[0053] Next, based on Figure 4 , and refer to Figure 1 to Figure 3 The code generation process (code generation method) for generating the information code CQ2 described so far will be described in detail.

[0054] In the code generation process, first, a public code Cd1 and a concealed code Cd2 are prepared. Specifically, in S11, the history management server 20 obtains the public code Cd1 by receiving it from the code output device 22. Next, in S12, the history management server 20 obtains a hash value reflecting the project information and the transaction record, and prepares concealed information mainly including the hash value. Then, in S13, the history management server 20 generates a concealed code Cd2 in which the concealed information is recorded.

[0055] In S14, the history management server 20 performs the following operations based on a predetermined rule (see Figure 3 ) are superimposed to synthesize the public code Cd1 and the concealed code Cd2 prepared in S11 to S13. As a result, an information code CQ2 is generated by two-dimensionally arranging white cells Cww, black cells Cbw, medium white cells Cwc, and medium black cells Cbc. In S15, the information code CQ2 generated in this way is issued to the trader TR.

[0056] Next, based on Figure 5 as well as Figure 6 , and refer to Figure 1 as well as Figure 2 The details of the code reading process (code reading method) of reading the concealment code Cd2 from the information code CQ2 will be described.

[0057] In S31 of the code reading process, the signal processing unit 41 detects the position and posture of the information code CQ2 reflected in the code photographed image based on the detection of the positioning pattern. In S32, the signal processing unit 41 applies pre-processing such as trapezoidal correction and binarization to the range where the information code CQ2 is reflected based on the information of the position and posture of the information code CQ2, and prepares a processed image suitable for code reading (hereinafter referred to as a corrected image Pc0, see Figure 6 ). The corrected image Pc0 is corrected to the shape of the information code CQ2 photographed from the front. In addition, in the corrected image Pc0, the grayscale value of the entire image is adjusted so that the grayscale values ​​of the white cell Cww and the middle white area wc, and the grayscale values ​​of the black cell Cbw and the middle black area bc are approximately the same value.

[0058] In S33, the signal processing unit 41 converts the middle white cell Cwc in the cell Ce of the information code CQ2 in the corrected image Pc0 into a black cell Cbw so that the middle white cell Cwc can be identified as the black cell Cbw. Specifically, the signal processing unit 41 performs image processing of the middle white area wc of the middle white cell Cwc by black-painting the outer black area bs surrounding the middle white area wc, thereby generating a first painted image Pp1.

[0059] Furthermore, in S34, the signal processing unit 41 converts the middle black cell Cbc in the cell Ce of the information code CQ2 in the first smeared image Pp1 into a white cell Cww, so that the middle black cell Cbc can be distinguished as the white cell Cww. Specifically, the signal processing unit 41 generates a first inverted image Pi1 in which the light and dark (black and white) of the colors in the first smeared image Pp1 are inverted. In the first inverted image Pi1, the middle black area bc becomes a white area in which black and white are inverted (hereinafter referred to as the inverted light area bci), and the outer white area ws becomes a black area in which black and white are inverted (hereinafter referred to as the inverted dark area wsi). The signal processing unit 41 performs image processing by inverting the light area bci with black smearing of the dark area wsi, and generates a second smeared image Pp2. The signal processing unit 41 again inverts the light and dark (black and white) of the colors in the second smeared image Pp2, and generates a second inverted image Pi2.

[0060] Through the above S33 and S34, the middle white cell Cwc and the middle black cell Cbc become black cells Cbw and white cells Cww, respectively, so the second inverted image Pi2 is actually an image of the restored concealment code Cd2. In S35, the signal processing unit 41 reads the concealment information from the restored concealment code Cd2 and ends the code reading process.

[0061] In addition, the code reading process may be performed by the history management server 20. In such a method, the code photographed image or the corrected image Pc0 is sent from the code scanner 23 to the history management server 20. The history management server 20 performs a process of reading the concealment code Cd2 from the received code photographed image or the corrected image Pc0.

[0062] In the present embodiment described so far, in addition to the white cells Cww and the black cells Cbw, the middle white cells Cwc forming the middle white region wc surrounded by the outer black region bs and the middle black cells Cbc forming the middle black region bc surrounded by the outer white region ws are used. Therefore, even if affected by the light irradiated to the information code CQ2, it is not easy to cause a situation where it becomes difficult to distinguish between the middle white cells Cwc and the middle black cells Cbc. As a result, it is possible to reduce the failure of code reading.

[0063] In addition, by using the medium white unit Cwc and the medium black unit Cbc, the public code Cd1 and the concealed code Cd2 can be overlapped without using the color unit or the intermediate gray unit Ce. Therefore, the information code CQ2 can be used while continuing to use the label printer 12 that only supports simple black and white printing. That is, since it is not necessary to introduce a printer that supports grayscale or color output, the increase in printing cost can be suppressed. As a result, for the public code Cd1 and the concealed code Cd2, the interchangeability of reading can be maintained while the interchangeability of code printing can be maintained.

[0064] In the information code CQ2 according to the present embodiment, when the public code Cd1 is read, the middle white cell Cwc is determined as the white cell Cww, and when the concealed code Cd2 is read, it is determined as the black cell Cbw. On the other hand, when the public code Cd1 is read, the middle black cell Cbc is determined as the black cell Cbw, and when the concealed code Cd2 is read, it is determined as the white cell Cww. With such an information code CQ2, the information code CQ2 to which the concealed information is added can be used while the existing code reader 13 is still used. As described above, the adaptability of the traceability system 120 to the old system is improved, and the introduction barrier of the traceability system 120 can be reduced.

[0065] In addition, in this embodiment, the shape of the middle white region wc is set to be similar to the shape of the middle white cell Cwc, and the shape of the middle black region bc is set to be similar to the shape of the middle black cell Cbc. As described above, even for the information code CQ2 including the middle white cell Cwc and the middle black cell Cbc, the generation of the image data of the information code CQ2 becomes easy. As a result, the processing load of the code generation process is reduced, and the information code CQ2 can be issued quickly.

[0066] In addition, in the present embodiment, in the step of making the middle white cell Cwc into the black cell Cbw, a first smeared image Pp1 is generated by smearing the middle white region wc with the dark color of the outer black region bs. Also, in the step of making the middle black cell Cbc into the white cell Cww, a first inverted image Pi1 is prepared by inverting the light and dark of the color of the first smeared image Pp1, and a second smeared image Pp2 is generated by smearing the inverted light region bci of the first inverted image Pi1 with the dark color of the inverted dark region wsi. Also, a second inverted image Pi2 is generated by inverting the light and dark of the color of the second smeared image Pp2. As described above, by sequentially smearing the image processing of the middle white cell Cww and the middle black cell Cbw, the processing of restoring the concealment code Cd2 from the information code CQ2 can be accelerated. As a result, the concealment information can be quickly read from the information code CQ2.

[0067] In the above embodiment, the signal processing unit 41 is equivalent to the "processing unit" for implementing the code reading method, the public code Cd1 is equivalent to the "first code", and the concealed code Cd2 is equivalent to the "second code". In addition, the white cell Cww is equivalent to the "light color cell", the black cell Cbw is equivalent to the "dark color cell", the medium white cell Cwc is equivalent to the "medium light color cell", and the medium black cell Cbc is equivalent to the "medium dark color cell". In addition, the medium white area wc is equivalent to the "medium light color area", the medium black area bc is equivalent to the "medium dark color area", the outer white area ws is equivalent to the "outer light color area", and the outer black area bs is equivalent to the "outer dark color area".

[0068] Technical ideas that can be further grasped from the embodiments described so far are described below as Supplementary Notes 1 and 2.

[0069] (Note 1)

[0070] A code generating device is a code generating device that generates an information code (CQ2) synthesized from a first code (Cd1) and a second code (Cd2), wherein the first code and the second code record information by a two-dimensional arrangement of a plurality of units (Ce), and comprises:

[0071] A code preparation unit (S11-S13) for preparing the first code and the second code; and

[0072] A code synthesis unit (S14) generates the information code by synthesizing the first code and the second code.

[0073] The code synthesis unit sets the cell at a position where both the first code and the second code are bright color cells (Cww) as the bright color cell.

[0074] The code synthesis unit sets the cell at a position where both the first code and the second code are dark cells (Cbw) as the dark cell.

[0075] The code synthesis unit sets the cell at the position where the first code is the light cell and the second code is the dark cell to a medium light cell (Cwc) in which a medium light area (wc) is surrounded by an outer dark area (bs).

[0076] The code synthesis unit sets the cell at a position where the first code is the dark cell and the second code is the light cell as a middle dark cell (Cbc) in which a middle dark region (bc) is surrounded by an outer light region (ws).

[0077] (Note 2)

[0078] A code reading device is a code reading device for reading the second code from an information code (CQ2) synthesized from a first code (Cd1) and a second code (Cd2), wherein the first code and the second code record information by a two-dimensional arrangement of a plurality of units (Ce), and comprising:

[0079] An image acquisition unit (S31) acquires a code-captured image showing the information code; and

[0080] The image conversion unit (S33, S34) makes the medium-light color unit (Cwc) having a medium-light color area (wc) surrounded by an outer dark color area (bs) in the above-mentioned unit of the above-mentioned information code become a dark color unit (Cbw), and makes the medium-dark color unit (Cbc) having a medium-dark color area (bc) surrounded by an outer bright color area (ws) in the above-mentioned unit of the above-mentioned information code become a light color unit (Cww).

[0081] In addition, in the above-mentioned embodiment, the history management server 20 corresponds to the "code generating device", and the history management server 20 or the code scanner 23 corresponds to the "code reading device".

[0082] (Other Embodiments)

[0083] As mentioned above, one embodiment according to the present disclosure has been described, but the present disclosure is not limited to the above embodiment and can be applied to various embodiments and combinations within the scope not departing from the gist of the present disclosure.

[0084] The shape and size of the middle black area bc and the middle white area wc are not limited to the above-mentioned embodiment and can be changed appropriately. For example, when the information code CQ2 is prepared as image data, one unit is composed of a plurality of rectangular pixels px arranged vertically and horizontally. Figure 7 In the variation 1 shown, one unit is formed by arranging three pixels px vertically and horizontally. In the middle white unit Cwc of such variation 1, one pixel px in the center forms the middle white area wc, and eight pixels px surrounding the central pixel px form the outer black area bs. Similarly, in the middle black unit Cbc, one pixel px in the center forms the middle black area bc, and eight pixels px surrounding the central pixel px form the outer white area ws.

[0085] exist Figure 8 In the variation 2 shown, a unit is formed by arranging many (for example, six) pixels px. In the variation 2, the middle white area wc and the middle black area bc are not rectangular, but are formed in a cross (cross) shape. As in the above variations 1 and 2, the shape and size of the middle white area wc and the middle black area bc can be appropriately changed according to the number and shape of the pixels px constituting each unit. In addition, the shape and size of the middle white area wc and the middle black area bc can be appropriately changed according to the resolution of the label printer 12 and the shape of each dot or according to the resolution of the display device and the shape of each display pixel.

[0086] exist Fig. 9 In the third variation shown, the middle white region wc and the middle black region bc are set to be squares, that is, rhombuses, in a posture rotated 45° relative to the outer edges of the middle white unit Cwc and the middle black unit Cbc. Fig.10 In the fourth modification shown, the middle white region wc and the middle black region bc are formed into circular shapes concentric with the middle white cell Cwc and the middle black cell Cbc.

[0087] Furthermore, in Modification 5, the centers of the middle white region wc and the middle black region bc are offset from the centers of the middle white unit Cwc and the middle black unit Cbc. In Modification 6, the shapes and sizes of the middle black region bc and the middle white region wc are different from each other. In addition, in Modification 7, the outer black region bs and the outer white region ws are shaped to partially surround the middle white region wc and the middle black region bc. As in Modification 7, as long as image processing of smearing the middle white region wc and the middle black region bc can be performed, the outer black region bs and the outer white region ws may not surround the entire circumference of the middle white region wc and the middle black region bc.

[0088] In the above embodiment, the light color forming the white unit Cww, the middle white area wc, and the outer white area ws may not be strictly white. For example, the background color of the label or the like on which the information code CQ2 is printed (for example, very light gray or ivory) may correspond to the light color. Similarly, the dark color forming the black unit Cbw, the middle black area bc, and the outer black area bs may not be strictly black. For example, the color of the ink used in the label printer 12 (for example, dark blue or dark green) may correspond to the dark color.

[0089] The public code Cd1 and the concealed code Cd2 are not limited to QR codes. Two-dimensional codes different from QR codes can be used as the first code and the second code, and combined into an information code. In addition, when QR codes are used as each code, the error correction capabilities (error correction levels) can also be different from each other. As an example, the error correction level of the concealed code Cd2 is higher than the error correction level of the public code Cd1.

[0090] The information code CQ2 according to the present disclosure may also be used by a system different from the distribution management system 110 and the traceability system 120. Furthermore, the information recorded in the first code and the second code which are the basis of the information code is not limited to the above-mentioned public information and confidential information, and may be appropriately changed according to the purpose of the information code.

[0091] In the above embodiment, the traceability code QRt is issued separately from the information code CQ2 used in the supply chain SC and attached to the final product FP. However, the information code CQ2 may be used as the traceability code QRt. In this case, the traceability confirmation application implements the above code reading process and provides the user terminal 50 with a function of reading the concealment code Cd2. In addition, the final product FP supplied through the supply chain SC may be appropriately changed. For example, various items such as automobiles, batteries, semiconductors, fresh food, aquatic products, food, flowers, pharmaceuticals, and chemicals can be managed through the traceability system 120.

[0092] The hash function used in the record management server 20 is a cryptographic hash function, which has the characteristics that the same hash value will not be output according to different inputs, and the input cannot be inferred from the output hash value. For example, instead of the above-mentioned SHA-256, encryption algorithms such as SHA-1, SHA-2 and SHA-3 can be appropriately used in conjunction with the output length (number of bits) that can be recorded in the concealment code Cd2 as concealed information. In addition, the code generation process implemented by the record management server 20 can also be implemented by the code output device 22 that becomes the edge side. In such a method, the code output device 22 is equivalent to a "code generation device".

[0093] In the above-mentioned embodiment, each function provided by the history management server and the code scanner etc. can also be provided by software and hardware executing the software, only by software, only by hardware, or by a complex combination thereof. In the case where such functions are provided by an electronic circuit as hardware, each function can also be provided by a digital circuit including a large number of logic circuits, or an analog circuit.

[0094] The processing unit (signal processing unit) of the above embodiment can be configured to include at least one CPU (Central Processing Unit: Central Processing Unit) and GPU (Graphics Processing Unit: Graphics Processing Unit) and other computing cores. In addition, the processing unit can be configured to also include FPGA (Field-Programmable Gate Array: Field Programmable Gate Array), NPU (Neural Network Processing Unit: Neural Network Processor) and other IP cores with dedicated functions.

[0095] The form of the storage medium (non-transitory tangible storage medium) storing the various programs related to the code generation and code reading of the present disclosure can be appropriately changed by adopting each storage unit of the above-mentioned embodiment. For example, the storage medium is not limited to the structure provided on the circuit substrate, and can be provided in the form of a memory card, etc., and inserted into the socket portion, and electrically connected to the bus of the computer. In addition, the storage medium can also be a CD and a hard disk drive, etc., which are the basis for copying the program to the computer.

[0096] The control unit and method described in the present disclosure may also be implemented by a dedicated computer that is programmed to execute one or more functions embodied by a computer program. Alternatively, the device and method described in the present disclosure may also be implemented by a dedicated hardware logic circuit. Alternatively, the device and method described in the present disclosure may also be implemented by one or more dedicated computers that are composed of a processor that executes a computer program and one or more hardware logic circuits. In addition, the computer program may also be stored in a computer-readable non-migratable tangible recording medium as an instruction executed by a computer.

Claims

1. An information code, which is an information code synthesized by a first code (Cd1) and a second code (Cd2), wherein the first code and the second code record information by a two-dimensional arrangement of a plurality of units (Ce), and the information code comprises: Bright color unit (Cww); Dark cell (Cbw); A medium light color cell (Cwc), in which a medium light color region (wc) surrounded by an outer dark color region (bs) is formed; and A medium dark color unit (Cbc) forms a medium dark color area (bc) surrounded by an outer light color area (ws) in the above-mentioned unit.

2. The information code according to claim 1, wherein: When the first code is read, the medium-bright color cell is determined as the bright color cell, and when the second code is read, the medium-bright color cell is determined as the dark color cell. When the first code is read, the medium dark color cell is determined as the dark color cell, and when the second code is read, the medium dark color cell is determined as the light color cell.

3. The information code according to claim 1 or 2, wherein: The shape of the above-mentioned medium-bright color area and the shape of the above-mentioned medium-bright color unit are similar shapes. The shape of the above-mentioned medium dark color area and the shape of the above-mentioned medium dark color unit are similar.

4. A code generation method, The processing performed by at least one processing unit (31) includes the following steps: preparing a first code (Cd1) and a second code (Cd2) for recording information by two-dimensionally arranging a plurality of cells (Ce) (S11 to S13); and Generate an information code (CQ2) (S14) by synthesizing the first code and the second code. In the step of synthesizing the first code and the second code: The cell at the position where both the first code and the second code are bright color cells (Cww) is set as the bright color cell; The cell at the position where both the first code and the second code are dark cells (Cbw) is set as the dark cell; The cell at the position where the first code is the light cell and the second code is the dark cell is set to be a light cell (Cwc) in which a light area (wc) is surrounded by an outer dark area (bs); and The cell at the position where the first code is the dark cell and the second code is the light cell is set as a middle dark cell (Cbc) in which a middle dark region (bc) is surrounded by an outer light region (ws).

5. A code reading method, comprising: reading the second code from an information code (CQ2) synthesized from a first code (Cd1) and a second code (Cd2), wherein the first code and the second code record information through a two-dimensional arrangement of a plurality of units (Ce), The processing performed by at least one processing unit (41) includes the following steps: Making a medium-light cell (Cwc) having a medium-light area (wc) surrounded by an outer dark area (bs) in the cell (Ce) of the information code a dark cell (Cbw) (S33); and A middle dark color cell (Cbc) having a middle dark color region (bc) surrounded by an outer light color region (ws) among the cells (Ce) of the information code is changed to a light color cell (Cww) (S34).

6. The code reading method according to claim 5, wherein: In the step of making the middle-light color unit become the dark color unit, a first smeared image (Pp1) is generated by smearing the middle-light color area with the dark color of the outer dark color area. In the step of making the above-mentioned medium dark color unit become the above-mentioned light color unit: generating a first inverted image (Pi1) in which the brightness and darkness of the colors in the first smeared image are inverted; Generate a second smeared image (Pp2) by smearing the inverted bright area (bci) of the middle dark area in the first inverted image with the dark color of the inverted dark area (wsi) of the outer bright area; and A second reversed image (Pi2) is generated by inverting the brightness and darkness of the second painted image.

Images