JP2012089177A - Creating program of two-dimensional code, and two-dimensional code - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide structure in which a user who reads a two-dimensional code by using a reading device of general specifications cannot recognize the presence of secret data.SOLUTION: A terminal identification code is arranged at the beginning of a code region by a step S111 in a QR code generated by code generation processing, and secrete data codes are arranged instead of a portion or whole part of a filler code by the step S111 after the terminal identification code. With this, since the secrete data codes arranged after the terminal identification code are not a reading target of a reading device of general specifications, it is recognized as if an empty QR code with no encoded data (without contents) has been read in such a reading device of the general specifications. Thus, a user of the reading device cannot recognize the presence of secret data. In this way, a user of the reading device of the general specifications can be prevented from recognizing the presence of the secret data.

Description

  The present invention relates to a program and a two-dimensional code for generating a two-dimensional code including data to be kept secret and hidden (hereinafter referred to as “secret data” or “secret data”).

  As a technique for generating or reading a two-dimensional code including confidential data, for example, there is an “information transmission method and portable terminal” disclosed in Patent Document 1 below. In this prior art, the transmission-side portable terminal encrypts transmission data with the encryption key input from the key input device, converts it into a QR code, generates a QR code (registered trademark), and displays it on the screen of the display device. (Patent Document 1; paragraphs 0020 and 0021, FIG. 4).

  On the other hand, in the mobile terminal on the reception side, the QR code image displayed on the screen of the mobile terminal on the transmission side is read by a camera or the like to determine whether the QR code is encrypted, and then encrypted. If so, request an encryption key. Then, the QR code is reversely converted and the transmission data is decrypted with the input encryption key to display the restored data on the screen (Patent Document 1; paragraph 0022, FIG. 5).

JP 2004-147006 A

  However, according to the “information transmission method and portable terminal” disclosed in Patent Document 1, when the encrypted data is reversely converted into a QR code, the encrypted data itself is usually used as character information. Since the information does not make sense, the information displayed on the screen of the mobile terminal or the like may be unclear or may be information corresponding to a control code that may affect the control of the screen display.

  For this reason, in the case of unclear information, the problem of being distrustful to the user of the mobile terminal or the user who can recognize that it is encrypted information. Can give rise to security problems because they can be inadvertently motivated to attempt to decipher.

  Further, in the case of information corresponding to a control code, there is a problem that the screen display is disturbed and may lead to other system problems.

The present invention has been made in order to solve the above-described problems, and an object of the present invention is to generate a two-dimensional code that cannot be recognized by a user who reads with a general-purpose reading device. To provide a program and a two-dimensional code.

To achieve the above object, according to a first aspect of the present invention, when the total number of disclosed data codes encoded as code words representing disclosed data is less than a capacity that can be accommodated in a code area where code words are to be arranged, An end identification code indicating the end of a code string formed by the disclosed data code arranged in the code area is arranged at the end of the code string, and a padding code that does not represent data is arranged in an empty part of the code area. As a two-dimensional code generating device, a program for causing a computer to function, wherein the disclosed data code does not exist and the total number of disclosed data codes is zero, and the end identification code is at the beginning of the code area. And a secret data code encoded as a code word representing the data to be concealed is part of the padding code or Instead of all, it characterized in that arranged after the end identification code.

  The second invention is arranged in the code area when the total number of disclosed data codes encoded as code words representing the disclosed data is less than the capacity that can be accommodated in the code area where the code word is to be arranged. A two-dimensional code in which an end identification code indicating the end of a code string formed by the disclosed data code is arranged at the end of the code string, and a padding code that does not represent data is arranged in an empty portion of the code area. The disclosed data code does not exist, the total number of disclosed data codes is zero, the termination identification code is arranged at the beginning of the code area, and the confidential data encoded as a code word representing the confidential data The code is arranged after the terminal identification code in place of part or all of the padding code.

  The two-dimensional code generated by the invention of claim 1 represents the data to be concealed while the disclosed data code does not exist and the total number of disclosed data codes is zero, the terminal identification code is arranged at the beginning of the code area The secret data code coded as a code word is placed after the terminal identification code in place of part or all of the padding code. Generally, a two-dimensional code reader is set to an algorithm specification that reads and decodes from the beginning of a data code arranged in a code area to a terminal identification code indicating the end of a code string in a two-dimensional code decoding process. Therefore, normally, a padding code or the like placed after the terminal identification code is not a target of reading. For this reason, by placing the end identification code at the beginning of the data code that should be placed in the code area (the beginning of the code area), a part or all of the padding code is replaced after the end identification code. The arranged data code is not decoded by a general-purpose reader, even if it is a readable code word. Thereby, the confidential data code cannot be read by disposing the data code (secret data code) to be concealed after the terminal identification code. Therefore, even if a general-purpose reader reads a two-dimensional code including such a secret data code, the existence of data to be concealed by the secret data code is not known. Can prevent the presence of confidential data.

  According to the invention of claim 2, a two-dimensional code having the same effect as that of claim 1 can be realized.

FIG. 1A is an explanatory diagram showing a QR code printer and a personal computer connected thereto according to the first embodiment of the present invention, and FIG. 1B shows a hardware configuration example of the QR code printer. It is a block diagram. It is a flowchart which shows the flow of the code production | generation process performed with the QR code printer which concerns on 1st Embodiment. FIGS. 3A and 3B are explanatory diagrams showing a format example of data and codes processed by the code generation process shown in FIG. 2, FIG. 3A shows an example of a data record of print data, and FIG. 3B shows steps S107 to S119. FIG. 3C shows an example 1 of the configuration of the secret code shown in FIG. 3B, FIG. 3D shows an example 2 of the configuration of the secret code shown in FIG. (E) shows a configuration example 3 of the secret code shown in FIG. 3 (B). It is explanatory drawing which shows the structural example of a 1 type QR code. It is a block diagram which shows the hardware structural example of a QR code reader . It is a flowchart which shows the flow of the decoding process performed by the control circuit of a QR code reader . It is a flowchart which shows the flow of the decoding process shown in FIG.

Embodiments of the present invention will be described below with reference to the drawings. In each embodiment described below, a QR code is given as an example of a two-dimensional code. However, the two-dimensional code according to the present invention is not limited to this, for example, a data matrix, a maxi code, a CP code, Even in the case of PDF417, RSS composite, etc., the present invention can be applied similarly to the QR code.

[First Embodiment]
First, the configuration of the QR code printer 10 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1A is an explanatory diagram showing a QR code printer 10 according to the first embodiment and a personal computer (hereinafter referred to as “personal computer”) 1 connected thereto, and FIG. FIG. 4B is a block diagram showing an example of the hardware configuration of the QR code printer 10.

  As shown in FIG. 1 (A), the QR code printer 10 is connected to the personal computer 1 via the cable 5 so that it can be output from the personal computer 1 and input to the QR code printer 10. It has a function of generating a QR code based on character data such as symbols (hereinafter collectively referred to as “print data”) and printing it on a label P or the like. Here, the “QR code” is in accordance with the Japanese Industrial Standard (JIS) two-dimensional code symbol-QR code-basic specification (JIS X 0510: 2004).

  The personal computer 1 includes a personal computer main body 2 and a display 3. The personal computer main body 2 includes an MPU, a main memory (main storage device), a hard disk (auxiliary storage device), an input / output interface, a communication interface, a keyboard (not shown). The display 3 is an information display device capable of displaying information output from the personal computer main body 2 when connected to the personal computer main body 2 on the screen.

  The personal computer main body 2 has a device driver for the QR code printer 10 installed (incorporated), and the user of the personal computer 1 includes print data including characters or the like that the user wants to print on the label P as a QR code. Can be arbitrarily output from the personal computer main body 2 to the QR code printer 10.

  On the other hand, as shown in FIG. 1B, the QR code printer 10 mainly includes an MPU 11, a memory 12, an interface 13, a roller control unit 14, a head control unit 15, a roller 17, a head 18, and the like. ing. These are mounted on a printed wiring board (not shown) or housed in a housing (not shown).

  The MPU 11 is a microcomputer capable of controlling the entire QR code printer 10 (hereinafter referred to as “microcomputer”) and can constitute an information processing apparatus together with a memory 12 connected via a memory bus, and has an information processing function. In addition to the memory 12, an interface 13, a roller control unit 14, and a head control unit 15 are connected to the MPU 11. A code generation process to be described later is executed by the MPU 11 and the memory 12.

  The memory 12 is a semiconductor memory device, and corresponds to, for example, a RAM (DRAM, SRAM, etc.) or a ROM (EPROM, EEPROM, etc.). In the RAM of the memory 12, in addition to the buffer area for storing the character data sent from the personal computer 1 described above, it is possible to secure a work area used by the MPU 11 for each processing such as arithmetic operation and logical operation. It is configured. The ROM stores in advance a predetermined program that can execute a code generation process and the like that will be described later, and a system program that can control each piece of hardware such as the roller control unit 14 and the head control unit 15.

  The interface 13 is an input interface that enables reception of print data and the like sent from the personal computer main body 2 of the personal computer 1 described above, and is connected to the MPU 11 via a serial bus or the like. The print data input to the MPU 11 via the interface 13 is processed and coded as will be described later by a code generation process.

  The roller control unit 14 is a control device that can control a driving mechanism (not shown) of the roller 17 and is connected to the MPU 11 via a serial bus or the like. Thus, the start and stop of rotation of the roller 17 or the direction of rotation is controlled according to the control signal received from the MPU 11.

  The head controller 15 is a thermal head that can print an arbitrary pattern on a label made of thermal paper, for example, and is connected to the MPU 11 via a serial bus or the like. In the present embodiment, the QR code generated by the code generation process described later can be printed on the thermal label, and the QR code is configured in synchronization with the paper feed timing of the thermal label by the roller control unit 14 described above. The position detection pattern, timing pattern, data code, etc. are printed on the label.

  In the following, the case of a thermal head will be described as an example of the head control unit 15. However, as long as a QR code can be printed, for example, an inkjet head or a dot impact head may be used. A laser printer, an LED printer, or the like may be used.

  By configuring the QR code printer 10 in this way, the print data output from the personal computer 1 and input to the QR code printer 10 is temporarily stored in the buffer area of the memory 12 via the interface 13, and then It is passed to the code generation process described in (1). Here, the code generation process will be described with reference to FIGS. FIG. 2 is a flowchart showing the flow of code generation processing. FIG. 3 shows a format example of data and code processed by the code generation process shown in FIG. Further, FIG. 4 shows a configuration example of a type 1 QR code.

  As shown in FIG. 2, the code generation process is started by the MPU 11 and the memory 12 that are activated when the QR code printer 10 is turned on. First, an initial setting process is performed in step S101. This process clears the work area of the memory 12 and the buffer area for storing print data, and clears predetermined flags and counters.

  In step S103, this step is repeated until print data is received in the process of determining whether or not print data has been received (S103; No). If it is determined that the print data has been received (S103; Yes), the process proceeds to the subsequent step S105. The data received here includes encryption key data in addition to print data. That is, as described later, when it is necessary to encrypt the secret data code, the encryption key data is also received in step S103. In addition, the print data received here is all the data (secret data) that you want to keep confidential and hidden from the third party, and does not include the data (disclosure data) disclosed to the third party. And Therefore, all the print data is processed as confidential data below.

  In the next step S105, processing for encoding the confidential data according to the JIS basic specification (JIS X 0510: 2004) is performed. Thereby, the secret data code coded as a code word representing the data to be secreted is generated. For example, as shown in FIG. 3, when the print data received in step S103 is the secret data α, β (FIG. 3A), the data length of the secret data code α encoded in step S105. And the data length and the sum of the secret data code β are calculated as the data length and added immediately before the secret data code α (FIG. 3B). In FIG. 3B, for the sake of convenience, the secret data code is expressed as “secret code”, and the secret identification code is expressed as “secret identifier”.

  In subsequent step S107, a process is performed in which the data length of the secret data code is calculated and obtained, and the data length encoded is added immediately before the secret data code. As a result, the area and range where the secret data code is arranged can be known, so when the QR code Q generated by this code generation process is decoded by a QR code reader or the like, how far is the secret data code, or Makes it possible to recognize whether it is an encrypted data code.

  In step S109, a process of adding a secret identification code before the data length encoded in step S107 is performed. This concealment identification code explicitly expresses that the data code arranged immediately after the termination identification code added in the next step S111 is "encoded as a code word representing concealed data". Thus, when the QR code Q generated by the code generation process is decoded by a QR code reader or the like, it is possible to recognize that the confidential data code is included in the QR code Q. For this reason, for example, it is possible to prevent data that is not to be read, garbled data, and the like from being mistakenly read as a secret data code, and to prevent the occurrence of malfunction caused by this.

  Then, in the subsequent step S111, processing for adding a terminal identification code immediately before the secret identification code is performed. The end identification code is, for example, “0000” in a 4-bit pattern. In the present embodiment, as described above, the print data received in step S103 does not include disclosure data. For this reason, as shown in FIG. 3B, there is no disclosed data code that should originally be positioned before the terminal identification code, and the terminal identification code is positioned at the head. In FIG. 3B, the terminal identification code is expressed as “end terminal” for convenience.

  In this way, after each process from step S105 to S111, a padding code and an error correction code are added after the secret data code. In this embodiment, as shown in FIG. Processing to encrypt the code may be performed.

  Specifically, in step S113, it is determined whether or not the secret data code needs to be encrypted by determining whether or not there is an encryption key. That is, when the encryption key data is received from the personal computer 1 in step S103, the encryption key is present (S113; Yes), and the process proceeds to step S115 to perform the encryption process. On the other hand, if the encryption key is not received from the personal computer 1 in step S103, there is no encryption key (S113; No), so the encryption process in step S115 is skipped and the process proceeds to step S117.

  Even if the encryption key data is not received in step S103, the encryption key is present when the personal computer 1 holds the encryption key in an information storage medium such as the memory 12 or the hard disk in advance (S113; Yes), encryption processing is performed in step S115.

  In step S115, a process for encrypting the secret data code is performed. In this process, for example, the secret data code is encrypted using a known visual decryption encryption technique (visual decryption secret sharing method). Thereby, the strength of security can be increased as compared with the case where such unencrypted plaintext data is added.

  For example, in the example shown in FIG. 3 (C), the “encrypted data” portion of the secret data code α is encrypted, and the “start digit”, “number of characters”, and “decryption key check data” are also generated. Is done. The “start digit” positioned first corresponds to an address value that can be expressed as the position information of the encrypted confidential data when the top of the print data is set to zero. The next “number of characters” is the number of characters of the encrypted confidential data. As a result, the QR code Q generated by the code generation process is decoded by a QR code reader or the like even when the data records are mixed in the positional relationship in the data record before being encoded as a code word. In this case, the decoded data can be arranged in the positional relationship before encoding based on the positional information.

  “Decryption key check data” added at the end is key specifying information that can specify a decryption key used for decrypting the cipher, and a common key encryption method (“ In the case of “private key encryption method”, the decryption key check data can also specify the encryption key. As a result, when the QR code Q generated by this code generation process is decoded by a QR code reader or the like, it is possible to easily specify the decryption key (decryptable key) of the secret data code, It can be determined whether or not there is.

  The secret data code β is configured in the same manner as the secret data code α, and the same information as the decryption key for decrypting the secret data code α may be added as the “decryption key check data”, or the secret data code When the secret data of the secret data code β is encrypted with another encryption key different from the α encryption key, “decryption key check data” for specifying another decryption key may be added. Thereby, when the QR code Q generated by this code generation process is decoded by a QR code reader or the like, it is possible to easily specify a key that can be decrypted for each secret data code, or a key that can be decrypted. It can be determined whether or not.

  In the following step S117, a process of adding a padding code after the secret data code is performed according to the JIS basic specification (JIS X 0510: 2004). Further, in step S119, an error correction code for the secret data is converted to the JIS basic specification. (JIS X 0510: 2004) is generated and further encoded to generate an error correction code.

  In step S121, each cell is generated based on the data code generated in step S119, and the process of arranging the cells in the data block shown in FIG. 4 is performed. That is, since the one-type QR code shown in FIG. 4 is formed in a square shape with 21 cells (modules) on one side, position detection patterns and format information provided at three corners (the hatched portion shown in FIG. 4). In addition, 26 blocks (A0 to A25) of data blocks configured by arranging 8 cells in 4 rows and 2 columns are arranged in the code area excluding the timing pattern.

  For example, in the example shown in FIG. 3 (B), the terminal identification code is placed at A0 at the beginning of the data area, and after this, usually after A1 corresponding to the position where the padding code is placed, that is, it is kept secret from A1. An identification code, a data length in A2, a secret identification code α in A3 to A6, and a secret identification code β in A7 to A9 are arranged. Then, similarly to the normal QR code, the error correction code is arranged in the last A20 to A25, and the padding code is arranged in A10 to A19 which are vacant portions therebetween. Since A15 and A18 are located across the timing pattern, A15 is divided into A15 and A15 ', and A18 is divided into A18 and A18'.

  In step S115, as shown in FIG. 3D, the decryption key itself may be added instead of the “decryption key check data”. Thus, when the QR code Q generated by the code generation process is decoded by a QR code reader or the like, for example, even if the QR code reader or the like does not have a decryption key for the secret data code α, the secret data The code α can be decrypted and restored to the original plaintext.

  Similarly, the decryption key itself may be added to the secret data code β instead of the “decryption key check data”. The decryption key to be added may be the same as the decryption key for decrypting the secret data code α, or the secret data of the secret data code β may be different from the encryption key of the secret data code α. May be added with another decryption key corresponding to the other encryption key. As a result, when the QR code Q generated by the code generation process is decoded by a QR code reader or the like, the QR code reader or the like does not have a corresponding decryption key for each secret data code. Also, each secret data code can be decrypted and returned to the original plaintext.

  Even if it is determined in step S113 that there is no encryption key (S113; No), as shown in FIG. 3 (E), the unencrypted plaintext data is added in step S115. Processing steps for adding “start digit” and “number of characters” may be provided between step S113 and step S117. As a result, the QR code Q generated by the code generation process is decoded by a QR code reader or the like even when the data records are mixed in the positional relationship in the data record before being encoded as a code word. In this case, the decoded data can be arranged in the positional relationship before encoding based on the positional information.

  As described above, according to the QR code printer 10 according to the first embodiment, in the QR code Q generated by the code generation process executed by the MPU 11, the terminal identification code is arranged at the beginning of the code area in step S111. In addition, after the termination identification code, the secret data code is arranged in place of a part or all of the padding code in step S111. In other words, by arranging the end identification code at the beginning of the data code that should be placed in the code area (the beginning of the code area), the data code that has no disclosed data code and the total number of disclosed data codes is zero. After the terminal identification code is generated, the secret data code is arranged in place of part or all of the padding code.

  As a result, the secret data code arranged after the terminal identification code is not read by a general-purpose reading device, and therefore there is no encoded data (no content) in such a general-specification reading device. Since it is recognized as if an empty QR code is read, the user of the reading device does not know the existence of confidential data. Accordingly, it is possible to prevent the user of the general-purpose reading apparatus from recognizing the existence of confidential data.

  Therefore, even if such a secret data code is included, since the data corresponding to the decode data of the secret data code is not displayed on the screen in the general-purpose reading device, the user can recognize the presence of the secret data. Therefore, the user is not distrusted or inadvertently motivated to try to decipher. Further, even if control data or the like corresponding to the decoded data of the secret data code is not displayed on the screen, the screen display is not disturbed.

  In the first embodiment described above, an example in which the QR code Q is printed on the label P by the QR code printer 10 has been described. However, the present invention is not limited to this, and the QR code Q is visually displayed. For example, the code generation process shown in FIG. 2 may be executed by the personal computer main body 2 to display the QR code Q on the display 3. In this case, since the code generation process can be conceptualized as a computer program, for example, “capacity that the total number of disclosed data codes encoded as code words representing data to be disclosed can be accommodated in a code area in which code words are to be arranged. If not, the end identification code indicating the end of the code string formed by the disclosed data code arranged in the code area is arranged at the end of the code string, and data is not represented in the empty part of the code area. A program for causing a computer to function as a two-dimensional code generating device for placing a padding code, wherein the disclosed data code does not exist and the total number of disclosed data codes is zero, and is the first in the code area The end identification code is arranged and encoded as a code word representing confidential data Anonymous Instead the data code in a part or all of the padding code, two-dimensional code generation program, characterized in that arranged after the end identification code. "And can grasp representable technical idea. As a result, the computer functioning as a two-dimensional code generation device using the two-dimensional code generation program has the same operations and effects as the MPU 11 and the like of the QR code printer 10 described above.

  In the first embodiment described above, the configuration in which the personal computer 1 is connected to the QR code printer 10 and print data is sent from the personal computer 1 has been described as an example. However, character data such as alphanumeric characters, kanji characters, and symbols is output. If the information processing apparatus is capable, the above-described operations and effects can be obtained even when a digital camera, a mobile phone, a handheld computer, a handy terminal, or the like having such a function is connected to the QR code printer 10. be able to.

Next, the configuration of the QR code reader 20 will be described. The QR code reader 20 according to the present configuration is a QR code reader 20 that can decode the QR code Q printed by the QR code printer 10 described in the first embodiment. The disclosed data code is also configured to be decodable. The configuration of the QR code Q that can be decoded by the QR code reader 20 has already been described with reference to FIG. 3 and FIG.

  First, the configuration of the QR code reader 20 will be described with reference to FIG. FIG. 5 is a block diagram illustrating a hardware configuration example of the QR code reader.

  As shown in FIG. 5, the QR code reader 20 mainly includes an optical system such as an illumination light source 21, a light receiving sensor 23, and an imaging lens 27, a memory 35, a control circuit 40, an operation switch 42, a liquid crystal display 46, and the like. And a power supply system such as a power switch 41 and a battery 49. These are mounted on a printed wiring board (not shown) or housed in a housing (not shown), and are configured in the same manner as a QR code reader (reading device) of general specifications in hardware.

The optical system includes an illumination light source 21, a light receiving sensor 23, an imaging lens 27, and the like. The illumination light source 21 functions as an illumination light source capable of emitting illumination light Lf, and includes, for example, a red LED and a diffusion lens, a condensing lens, and the like provided on the emission side of the LED. In this configuration , illumination light sources 21 are provided on both sides of the light receiving sensor 23, and the illumination light Lf can be irradiated toward the label P through a reading port of a case (not shown). The QR code Q described in the first embodiment is printed on the label P.

  The light receiving sensor 23 is configured to receive the reflected light Lr irradiated and reflected on the label P or the QR code Q. For example, a light receiving element which is a solid-state imaging element such as a C-MOS or CCD is two-dimensionally arranged. The arranged area sensor corresponds to this. The light receiving sensor 23 is mounted on a printed wiring board (not shown) so that incident light incident through the imaging lens 27 can be received by the light receiving surface 23a.

  The imaging lens 27 functions as an imaging optical system capable of condensing incident light incident from the outside via a reading port and forming an image on the light receiving surface 23a of the light receiving sensor 23. And a plurality of condensing lenses housed in the lens barrel.

  Next, a configuration outline of the microcomputer system will be described. The microcomputer system includes an amplification circuit 31, an A / D conversion circuit 33, a memory 35, an address generation circuit 36, a synchronization signal generation circuit 38, a control circuit 40, an operation switch 42, an LED 43, a buzzer 44, a liquid crystal display 46, and a communication interface 48. Etc. As the name suggests, this microcomputer system is composed of a control circuit 40 and a memory 35 that can function as a microcomputer.

  An image signal output from the light receiving sensor 23 of the optical system is amplified by a predetermined gain by being input to the amplification circuit 31 and then converted from an analog signal to a digital signal when input to the A / D conversion circuit 33. Is done. When the digitized image signal, that is, image data is input to the memory 35, it is stored in the image data storage area. The synchronization signal generation circuit 38 is configured to generate a synchronization signal for the light receiving sensor 23 and the address generation circuit 36. The address generation circuit 36 is based on the synchronization signal supplied from the synchronization signal generation circuit 38. Thus, the storage address of the image data stored in the memory 35 can be generated.

  The memory 35 is a semiconductor memory device, and corresponds to, for example, a RAM (DRAM, SRAM, etc.) or a ROM (EPROM, EEPROM, etc.). In addition to the above-described image data storage area, the RAM of the memory 35 is configured so as to be able to secure a work area used by the control circuit 40 during each processing such as arithmetic operation and logical operation. In addition, the ROM stores in advance a predetermined program capable of executing a decoding process described later, a system program capable of controlling each hardware such as the illumination light source 21 and the light receiving sensor 23, and the like.

The control circuit 40 is a microcomputer capable of controlling the entire QR code reader 20 and includes a CPU, a system bus, an input / output interface, and the like, and can constitute an information processing apparatus together with the memory 35 and has an information processing function. The control circuit 40 is configured to be connectable to various input / output devices via a built-in input / output interface. In this configuration , the power switch 41, the operation switch 42, the LED 43, the buzzer 44, and a liquid crystal display are provided. Device 46, communication interface 48, etc. are connected.

  Thereby, for example, monitoring and management of the power switch 41 and the operation switch 42, turning on / off the LED 43 functioning as an indicator, turning on / off the buzzer 44 capable of generating a beep sound and an alarm sound, and further reading the QR code Screen control of the liquid crystal display 46 capable of displaying the code content by Q, communication control of the communication interface 48 enabling serial communication with an external device, and the like are enabled. The external device connected to the communication interface 48 includes a host computer HST corresponding to the host system of the QR code reader 20 and the like.

  The power supply system includes a power switch 41, a battery 49, and the like. When the power switch 41 managed by the control circuit 40 is turned on and off, the conduction of the drive voltage supplied from the battery 49 to each of the above-described devices and circuits is performed. Or shut off is controlled. The battery 49 is a secondary battery capable of generating a predetermined DC voltage, and corresponds to, for example, a lithium ion battery. Further, the battery 49 may be configured to receive power supply from an external device such as the host computer HST connected via the communication interface 48 without using the battery 49. In this case, the battery 49 is unnecessary.

  By configuring the QR code reader 20 in this way, for example, when the power switch 41 is turned on and a predetermined self-diagnosis process or the like is normally completed and the QR code Q can be read, the illumination light Lf is emitted. The input of the operation switch 42 (for example, a trigger switch) is given. Accordingly, when the user pulls the trigger switch to turn it on, the control circuit 40 outputs a light emission signal to the illumination light source 21 based on the synchronization signal, and the illumination light source 21 that has received the light emission signal turns on the LED. Light is emitted to irradiate illumination light Lf.

  Then, the illumination light Lf irradiated to the QR code Q is reflected, and the reflected light Lr enters the imaging lens 27 through the reading port, so that the image of the QR code Q is formed on the light receiving surface 23a of the light receiving sensor 23. Is imaged. Thereby, since the image of the QR code Q exposes the light receiving sensor 23, the image data of the QR code Q subjected to the image processing by the microcomputer system described above will be described below through the image data storage area of the memory 35. Passed to the decoding process.

  Here, the decoding process will be described with reference to FIG. 4, FIG. 6, and FIG. FIG. 6 is a flowchart showing the flow of the decoding process. FIG. 7 is a flowchart showing the flow of the decoding process shown in FIG. FIG. 4 is an explanatory diagram showing a configuration example of a type 1 QR code.

  As shown in FIG. 6, the decoding process is started by the control circuit 40 and the memory 35 that are activated when the QR code reader 20 is turned on. First, an initial setting process is performed in step S201. This process clears the work area of the memory 35 and the image data storage area for storing image data, and clears predetermined flags, counters, and the like. It is assumed that the QR code reader 20 described here is connected to the host computer HST, and obtains decryption key data from the host computer HST as setting data.

  In step S203, processing for clearing the count value of the timer is performed. The timer whose counter value is cleared in step S203 measures the elapse of a predetermined time in the next step S205.

  In step S205, processing is performed to determine whether or not a predetermined time has elapsed by the previous timer. That is, it is necessary to determine whether or not the decryption key data is included in the setting data sent from the host computer HST. For example, it is determined whether or not 5 seconds have passed as the predetermined time. If no data related to encryption is sent from the host computer HST before this time elapses, the process proceeds to step S207 as the predetermined time elapses (S205; Yes).

  On the other hand, when the predetermined time has not elapsed (S205; No), a process of determining whether or not a decryption key (decryption key) has been received in the next step S209 is performed. If it is determined that it has been received (S209; Yes), the process proceeds to the subsequent step S211. If it cannot be determined that it has been received (S209; No), the process proceeds to step S205 described above. The processing is returned and the passage of time is determined again.

  If it is determined in step S205 that the predetermined time has elapsed (S205; Yes), “0” is set to a predetermined flag in step S207. This flag indicates whether or not the secret data code of the QR code Q is decrypted with the decryption key. When “0” is set, this flag indicates that decryption with the decryption key is not performed. When set, it indicates that decryption is performed with the decryption key. For this reason, when it is determined by 209 that the decryption key has been received (S209; Yes), a process of setting “1” to this flag is performed in the subsequent step S211.

  When “1” is set in the predetermined flag in step S211, a process of acquiring image data is performed in the subsequent step 213. That is, a process of reading out image data stored from the image data storage area of the memory 35 is performed. Thereby, for example, a code image of QR code Q as shown in FIG. 4 is obtained.

  In subsequent step S215, processing for detecting a position detection pattern is performed. That is, as shown in FIG. 4, since the QR code Q is provided with position detection patterns at its three corners, the code outline of the QR code Q is detected in the next step S217 by detecting these.

  Then, by performing the process of calculating the center coordinates of each cell in step S219, the monochrome of each cell is determined in the next step S221. This makes it possible to recognize the format information shown in FIG. 4 (the hatched portion shown in FIG. 4) and the data block. If there is a missing data block in the subsequent step S223, the block is error-corrected. Determine whether it is possible.

  If it can be determined in step S223 that error correction is possible (S223; OK), error correction is performed and decoding processing is performed in subsequent step S300. On the other hand, if it cannot be determined in step S223 that the error can be corrected (S223; NG), the error cannot be corrected. Therefore, the process proceeds to step S213, and image data is acquired again, and steps S215 to S221 are performed. Perform each process.

  Details of step S300 are shown in FIG. 7, and the decoding process will be described below with reference to FIG. As shown in FIG. 7, in the decoding process, first, a process of setting 0 (zero) to the counters n and Cnt is performed in step S301. The counter n functions as a variable indicating the order of data codes constituting the QR code Q in the present decoding process. The counter Cnt functions as a variable indicating the number of disclosed data codes included in a normal specification QR code or the like.

  In step S303, processing for obtaining the nth data code pointed to by the counter n is performed. Then, in the subsequent step S305, a process for determining whether or not the nth data code acquired in step S303 is a terminal identification code is performed. As a result, when it is determined that the data code is the termination identification code (S305; Yes), the read QR code is the QR code Q generated according to the first embodiment described above, or the termination identification code. Since the normal data code arranged before is no longer included in the QR code, the process proceeds to step S315.

  On the other hand, when it is not possible to determine that the data code is a terminal identification code (S305; No), the read QR code is not the QR code Q generated by the first embodiment described above, but the normal specification QR. Since a normal data code still exists before the terminal identification code, the process proceeds to the subsequent step S307, and the next data code, that is, the (n + 1) th data code is replaced with the code number i. To get. As described with reference to FIG. 3C in the first embodiment, this is based on the fact that the number of characters is stored at the position corresponding to the second character of the data code. It is described in “8.4 Data Encoding” in JIS Basic Specification (JIS X 0510: 2004).

  When the number of codes i is acquired in step S307, in the subsequent step S309, a process for acquiring data codes for the number of characters (i) is performed. A process of decoding (decoding) a data code encoded as a code word is performed.

  When the decoding process in step S311 is completed, in step S313, “n + i + 1” is added to the counter n so that the counter n indicates the next data code, and “Cnt + 1” is added so that the counter Cnt adds 1 to the number of disclosed data codes. "Is set to Cnt, and then the process returns to step S303 to acquire the nth data code.

  As described above, in steps S303 to S313, a process of obtaining and decoding a normal data code (first data code, disclosed data code) that is arranged in front of the terminal identification code and originally decoded is performed.

  If it is determined in step S305 that the acquired n-th data code is a termination identification code (S305; Yes), a process of determining whether or not the value of the counter Cnt exceeds 0 (zero) in step S314. Done.

That is, when the value of the counter Cnt that counts the number of disclosed data codes exceeds 0 (zero) (S343; Yes), the read data code includes the disclosed data code. Therefore, the process proceeds to step S343 without performing each process related to the secret data code in steps S315 to S341. Thus, before the end identification code, it is possible to disclose data code (first data code) is equal to or is arranged, the control circuit 40 or the like to perform this step S314 is "No. 1 data code determination means ”.

  On the other hand, when the value of the counter Cnt does not exceed 0 (zero) (S343; No), that is, when the value of the counter Cnt is 0 (zero), the read QR code contains disclosed data. Since the code is not included, in order to acquire the next data code, the process of setting n + 1 to the counter n is performed in step S315, and then the nth data code is acquired in step S317.

In subsequent step S319, processing for determining whether or not the n-th data code acquired in step S317 is a secret identification code is performed. Thus, after the end identification code, it can be determined whether the secret data code (second data codes) are arranged, the control circuit 40 or the like to perform this step S319, the "second Can be equivalent to “data code determination means”.

  If it is determined that the data code is a confidential identification code (S319; Yes), since the confidential data code exists immediately after the confidential identification code, the process proceeds to the subsequent step S321. The code number j is acquired for the next data code, that is, the (n + 1) th data code. This is also based on the fact that the number of characters is stored at the position corresponding to the second character of the data code, as in step S309.

  When it is determined in step S319 that a secret identification code is arranged, for example, the host computer HST is notified that the secret identification code is arranged in the QR code Q. You may do it. As a result, the host computer HST can recognize that the data code behind the terminal identification code is a secret data code. In addition, in the code area after the termination identification code (the empty area of the code area) where only the padding code is originally placed, it is other than the padding code and is not a secret data code (for example, it corresponds to the padding code due to data corruption) In this case, since the information indicating that the data is a secret data code is not output to the host computer HST, a malfunction that may be caused by decoding something other than the secret data code is prevented. be able to.

  On the other hand, when it cannot be determined that the data code is a confidential identification code (S319; No), no more confidential data code is included in the QR code Q after the confidential identification code. Therefore, this decoding process is finished, step S300 shown in FIG. 6 is finished, and the decoding process is finished.

  When the code number j is obtained in step S321, in the subsequent step S323, a process for obtaining the data code for the number of characters (j) is performed, and in step S325, the counter n indicates the next data code, that is, the secret data code. As described above, after the process of setting “n + j + 2” to the counter n is performed, a process of acquiring n-th decryption key check data (key specifying information) is performed in step S327.

  In the subsequent step S329, a process is performed to determine whether or not “1” is set in the above-described predetermined flag, that is, whether or not the secret data code of the QR code Q is decrypted with the decryption key. If “1” is not set in the flag (S329; No), it is not necessary to perform decryption with the decryption key. Therefore, the processes of steps S331 and 333 are skipped and the process proceeds to step S335. .

  On the other hand, when “1” is set in the predetermined flag (S329; Yes), since it is necessary to decrypt with the decryption key, based on the decryption key check data acquired in the previous step S327, In step S331, it is determined whether or not the decryption key received from the host computer HST in step S209 is suitable as a key for decrypting the encrypted data of the nth secret data code.

If it is determined that the decryption key is suitable for step S331 (S331; Yes), the encrypted data is decrypted in the subsequent step S333. The encryption here uses the well-known visual decryption type encryption technique (visual decryption type secret sharing method) described in the first embodiment, so that the encrypted data of the secret data code is like this. Even if it is encrypted by a visual decryption type encryption technique, it can be decrypted and returned to the original plaintext. The control circuit 40 or the like to perform this step S333 is may correspond to "decode unit".

On the other hand, if it cannot be determined that the decryption key is compatible with step S331 (S331; No), step S333 is skipped without decrypting the n-th secret data code, and the process proceeds to step S335. Migrate processing. As a result, if the decryption key of the QR code reader 20 is not a decryption key that can decrypt the nth secret data code, the nth secret data code is neither decrypted nor decrypted, thereby suppressing unnecessary decryption processing. be able to. It should be noted that the control circuit 40 or the like that executes this step S331 can correspond to “key matching determination means”.

  In step S335, a process for decoding the secret data code is performed. That is, since the encrypted data can be decrypted in the previous step S333 or is not originally encrypted, the secret data code corresponding to the plaintext is decrypted (decoded).

  When the decoding process in step S335 is completed, a process of setting “n + 1” to the counter n is performed in step S337 so that the counter n indicates the next data code. Then, in the subsequent step S339, the nth data code is set. The process of acquiring is performed.

  In step S341, processing is performed to determine whether the nth data code acquired in step S339 is a padding code. Thereby, if the nth data code is a padding code (S341; Yes), since the QR code Q does not contain any more secret data code, the following step S343 is performed. The process is transferred to.

  On the other hand, if it is not determined in step S341 that the n-th data code is a padding code (S341; No), the n-th data code is a secret data code, so the process proceeds to step S321. , And the number n of the (n + 1) th data code is acquired again to perform the same processing as described above.

As described above, in steps S317, S321 to S327, S333, and S335, processing for obtaining and decoding the data code (second data code, secret data code) that is arranged behind the terminal identification code and is not originally decoded. Is done. Therefore, the control circuit 40 or the like to perform each of these steps, may correspond to "decode unit".

  In step S343, a process of determining whether or not the value of the counter Cnt exceeds 0 (zero) is performed. That is, when the value of the counter Cnt that counts the number of disclosed data codes exceeds 0 (zero) (S343; Yes), the read data code includes the disclosed data code. Therefore, the disclosed data decoded in step S311 is output to the liquid crystal display 46 in the next step S345.

  On the other hand, when the value of the counter Cnt counting the number of disclosed data codes does not exceed 0 (zero), that is, 0 (zero) (S343; No), the read QR code is changed to Since no disclosure data code is included, the output process in the subsequent step S345 is skipped, and the process proceeds to the next step S347.

  In step S347, processing for outputting disclosed data and secret data to the host computer HST is performed. That is, when the disclosed data code is included in the read QR code, the disclosed data is decoded, and when the read QR code contains the confidential data code, the confidential data obtained by decoding the disclosed data code is displayed. , Respectively, to the host computer HST. If the host computer HST is not connected to the QR code reader 20, the process proceeds to the next step S349 without performing the output process in this step S347.

  In the subsequent step S349, a process for sounding the buzzer 44 and a process for lighting the LED 43 are performed. That is, the operator operating the QR code reader 20 is notified that the disclosed data code or the confidential data code included in the read QR code has been decoded. In the present embodiment, the buzzer 44 and the LED 43 indicate that the QR code reader 20 has been decoded even when it is not possible to determine that the decryption key is suitable by the determination processing in step S331 (S331; No). Notice. When the process in step S349 is completed, the present decoding process is terminated and step S300 shown in FIG. 6 is terminated, and thus a series of decoding processes are terminated.

  As a result, even if the decryption key is not a decryptable key, the operator is informed that the reading has been completed in this way, and therefore the operator is informed that the QR code contains confidential data that cannot be decrypted. It can be made difficult to know. In addition, since the decryption key does not match, it is possible to prevent a useless operation by an operator who reads a QR code that cannot be decrypted many times. Therefore, since the possibility of giving the operator an inadvertent motive to try to decode the QR code is reduced, the strength of security can be increased, and the operability can be improved.

As described above, according to the QR code reader 20 according to the present configuration , in step S314, it is determined whether or not the disclosed data code (first data code) is arranged before the termination identification code. In S319, it is determined whether or not a secret data code (second data code) is placed after the termination identification code. If it is determined in step S314 that no disclosed data code is arranged (S343; No), and if it is determined in step S319 that a secret data code is arranged (S319; Yes), steps S321 to S341 are performed. Decode the secret data code.

  As a result, there is no disclosed data code that should originally be placed in the data area, and the secret data code is placed in the code area (empty part of the code area) after the termination identification code where only the padding code is placed. If so, the secret data code can be decoded. Therefore, it is possible to decode the data code existing in the empty part of the code area where the code word is to be arranged. That is, it is possible to decode even a QR code Q in which a termination identification code is arranged at the beginning of the code area and a secret data code is arranged after the termination identification code.

  In other words, like the QR code Q printed by the QR code printer 10 described in the first embodiment, the end identification code is arranged at the beginning of the code area (the beginning of the data code to be arranged in the code area), and the end Even if the secret data code is arranged after the identification code, such a QR code Q can be decoded.

In the decoding process described above, the nth decryption key check data is obtained in step S327. For example, as described with reference to FIG. 3D in the first embodiment, the decryption key itself is used. May be added to the secret data code, the n-th decryption key may be obtained instead of step S327. Thus, even if the QR code reader 20 does not have a decryption key (decryptable key) for the secret data code, the secret data code can be decrypted and returned to the original plaintext. In this case, the control circuit 40 or the like for executing processing "Get n-th decryption key" may correspond to "key separation means".

  Even if each encrypted data code is encrypted with a different encryption key, if each decryption key is added to each encrypted data code, the nth decryption is performed instead of step S327. By configuring so as to acquire the key, each secret data code can be decrypted and returned to the original plaintext even if the QR code reader 20 does not have a decryption key for the secret data code.

  Furthermore, in the decoding process described above, the n-th decryption key check data is acquired in step S327. For example, as described with reference to FIG. If the “start digit” is added to the secret data code, instead of this step S329, the “start digit” is separated from the secret data code, and the secret data is based on the separated “start digit”. The secret data obtained by decoding (decoding) the code may be arranged in a positional relationship in the data record before being encoded. As a result, even if the positional relationship in the data record before being coded as a code word is mixed before and after, the decoded data is arranged in the positional relationship before coding based on this positional information. be able to.

  Further, in the decoding process described above, the presence or absence of the disclosed data code is determined in step S314, and when the disclosed data exists (S343; Yes), without performing each process related to the secret data code in steps S315 to S341, Although the decoded disclosure data is configured to be displayed in step S345, the processing may be directly shifted from step S305 to step S315 without performing the determination processing in step S314. As a result, even when there is disclosed data, since each process related to the secret data code in steps S315 to S341 is performed, both the QR code Q including both the disclosed data code and the secret data code are included. Can be decoded.

1 ... PC 10 ... QR code printer 11 ... MPU
12 ... Memory 20 ... QR code reader (two-dimensional code reader)
35. Memory (first data code judging means, second data code judging means, decoding means, secret identification code judging means, secret information output means, decoding means, key matching judgment means, key separating means)
40. Control circuit (first data code judging means, second data code judging means, decoding means, secret identification code judging means, secret information output means, decrypting means, key matching judgment means, key separating means)
HST ... Host computer P ... Label Q ... QR code (two-dimensional code)

Claims (2)

  When the total number of disclosed data codes encoded as code words representing data to be disclosed is less than the capacity that can be accommodated in the code area where the code word is to be arranged, the disclosed data code arranged in the code area forms A computer is caused to function as a two-dimensional code generation device that arranges an end identification code indicating the end of a code string at the end of the code string and places a padding code that does not represent data in an empty portion of the code area. As a code word representing data to be concealed, the disclosed data code does not exist, the total number of disclosed data codes is zero, the termination identification code is arranged at the beginning of the code area Replace the coded secret data code with a part or all of the padding code and replace the terminal identification code Two-dimensional code generation program, characterized in that the arrangement.   When the total number of disclosed data codes encoded as code words representing data to be disclosed is less than the capacity that can be accommodated in the code area where the code word is to be arranged, the disclosed data code arranged in the code area forms A two-dimensional code in which an end identification code indicating the end of a code string is arranged at the end of the code string, and a padding code that does not represent data is arranged in an empty part of the code area,
  The disclosure data code does not exist, the total number of the disclosure data codes is zero, the termination identification code is arranged at the beginning of the code area, and
  A two-dimensional code characterized in that a secret data code encoded as a code word representing data to be concealed is arranged after the terminal identification code instead of a part or all of the padding code.

Images