JP2012089179A - Creating program of two-dimensional code, and two-dimensional code - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide structure related to a two-dimensional code in which a user who reads the two-dimensional code by using a reading device of general specifications cannot recognize the presence of secret data.SOLUTION: In two-dimensional codes generated by code generation processing, secrete data codes are arranged after a terminal identification code instead of a portion or whole part of a filler code by a step S133. 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, even if the two-dimensional codes including such secrete data codes are read by the reading device of general specifications, the presence of data to be made secrete by the secrete data codes is not recognized. In this way, a user of the reading device of general specifications can be prevented from recognizing the presence of secret data.

Description

The present invention relates to a two-dimensional code generation program and a two-dimensional code including secret data (hereinafter referred to as “confidential data” or “confidential 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 mobile terminal on the transmission side encrypts transmission data with the encryption key input from the key input device, converts it into a QR code (registered trademark), generates a QR code, 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. And providing 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 in which 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, replacing a secret data code encoded as a code word representing data to be concealed with a part or all of the padding code, It is arranged after the end identification code.

  The invention of claim 2 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. In addition, the end identification code indicating the end of the code string formed by the disclosed data code is disposed at the end of the code string, and a two-dimensional code in which a padding code that does not represent data is disposed in an empty portion of the code area. Thus, the secret data code encoded as a code word representing the data to be concealed is arranged after the terminal identification code instead of a part or all of the padding code.

The two-dimensional code generated by the invention of claim 1 is arranged after the terminal identification code instead of a part or all of the padding code with the secret data code encoded as a code word representing the data to be concealed. 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, a data code arranged in place of part or all of the padding code after the terminal identification code cannot be decoded by a general-purpose reader, even if it is a readable code word. Since there is no data code (secret data code) to be concealed after the terminal identification code, the data code arranged before the terminal identification code can be read, but the secret data code cannot be read. Can not. 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 processing shown in FIG. 2, FIG. 3A is an example of a data record of print data, and FIG. 3C is an example after adding each code in steps S121 to S137, FIG. 3D is a configuration example 1 of the secret code shown in FIG. 3C, and FIG. FIG. 3C shows a configuration example 2 of the secret code, and FIG. 3F shows a configuration example 3 of the secret code shown in FIG. 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 . 6 is a flowchart showing a flow of decoding processing executed by a control circuit of the QR code reader of FIG. 5 . It is a flowchart which shows the flow of the decoding process shown in FIG. It is a flowchart which shows the flow of the code production | generation process performed with the QR code printer which concerns on 2nd Embodiment of this invention. FIG. 9A is an explanatory diagram showing an example of data and code formats processed by the code generation process shown in FIG. 8, FIG. 9A is an example of a data record of print data, and FIG. 9B is rearranged in step S115. 9C is an example after adding each code in steps S121 to S137, FIG. 9D is a configuration example 1 of the secret code shown in FIG. 9C, and FIG. FIG. 9C shows a configuration example 2 of the secret code, and FIG. 9F shows a configuration example 3 of the secret code shown in FIG. 9C. 7 is a flowchart showing a flow of decoding processing executed by a control circuit of a QR code reader different from the example of FIG. 6 and the like . FIG. 11 is a flowchart showing a flow of decoding processing shown in FIG. 10. FIG. It is a flowchart which shows the flow of the code production | generation process performed with the QR code printer which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the flow of the process shown in FIG. FIG. 14A is an explanatory diagram showing a code format example processed by the processing shown in FIG. 13, and FIG. 14A is an example of the code generated by the code generation process of the second embodiment (corresponding to FIG. 9C). 14B is an example of a secret code that has been distributed and arranged in step S500. FIG. 14C is an example of a secret code in which bits are rearranged or bit values converted in step S500. 14D is a configuration example of the secret code shown in FIG. 14C, and FIG. 14E is a configuration example of the secret code generated by the code generation processing of the second embodiment as a comparison with FIG. 14D. (Corresponding to FIG. 9D). 11 is a flowchart showing a flow of decoding processing executed by a control circuit of a QR code reader different from the examples of FIGS. It is a flowchart which shows the flow of the decoding process shown in FIG. It is a flowchart which shows the flow of the extraction process shown in FIG. 16 is a flowchart showing a flow of decoding processing executed by a control circuit of a QR code reader different from the examples of FIG. 6, FIG. 10, FIG . FIG. 19 is a flowchart showing a flow of read flag setting processing executed by the control circuit of the QR code reader of FIG. 18. 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). When it is determined that the print data has been received (S103; Yes), the timer count value is cleared in the subsequent step S105. The timer whose counter value is cleared in step S105 measures the lapse of a predetermined time in the next step S107.

  In step S107, 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 print data sent from the personal computer 1 includes data related to encryption or the like in the next step S111. For example, whether or not 1 second has elapsed as a predetermined time. If the data related to encryption is not sent from the personal computer 1 by the time elapsed, the process proceeds to step S109 as the predetermined time elapses (S107; Yes).

  On the other hand, if the predetermined time has not elapsed (S107; No), in the data record of data that needs to be concealed (hereinafter referred to as “confidential data”) as data relating to encryption or the like in the next step S111. A process is performed to determine whether or not the secret data position information indicating the positional relationship and the encryption key (encryption key) used for encryption have been received. If it is determined that these have been received (S111; Yes), the process proceeds to the subsequent step S113. If it is not possible to determine that these have been received (S111; No), the steps described above are performed. The process returns to S107, and the passage of time is determined again.

  If it is determined in step S107 that the predetermined time has elapsed (S107; Yes), “0” is set to a predetermined flag in step S109. This flag indicates whether or not confidential data is included in the print data. When “0” is set, it indicates that confidential data is not included and “1” is set. Indicates that confidential data is included. For this reason, if it is determined in step S111 that data relating to encryption or the like is received (S111; Yes), a process of setting “1” to this flag is performed in subsequent step S113.

  When “1” is set to the predetermined flag in step S113, a process of rearranging the disclosed data and the confidential data is performed in subsequent step 115. That is, the print data includes data disclosed to a third party (disclosure data) and data (secret data) that the third party wants to keep secret and concealed. If they are mixed, based on the “positional information indicating the positional relationship in the data record of the confidential data” received in step S111, the order of the data is changed and divided into a collection of disclosed data and a collection of confidential data. Process.

  For example, as shown in FIG. 3 (A), for example, the print data record sent from the personal computer 1 includes data arranged in the order of disclosure data A, secret data α, disclosure data B, and secret data β. If this is the case, in step S115, the order of these data is changed, and as shown in FIG. 3B, a process of rearranging the disclosed data A, the disclosed data B, the secret data α, and the secret data β is performed. As a result, the disclosed data and the confidential data are collected together, so that the terminal identification code addition processing in step 121 and the confidential identification code addition processing in step S125 are facilitated.

  In the next step S117, a process of encoding each data such as disclosed data and secret data in accordance with JIS basic specifications (JIS X 0510: 2004) is performed. As a result, a disclosed data code encoded as a code word representing data to be disclosed is generated, and a secret data code encoded as a code word representing data to be concealed is generated.

  In the subsequent step S119, an error correction code for each data of the disclosed data is generated in accordance with JIS basic specifications (JIS X 0510: 2004), and further encoded to generate an error correction code. For confidential data, for example, as with the disclosed data, an error correction code is generated using the error correction code generation algorithm described in the JIS basic specification (JIS X 0510: 2004) and encoded. Then, a process for generating an error correction code is performed.

  Then, in the subsequent step S121, processing for adding a terminal identification code after the disclosed data code is performed. The end identification code is, for example, “0000” in a 4-bit pattern, and is located immediately after the disclosed data code B following the disclosed data code A, as shown in FIG. In FIG. 3C, for the sake of convenience, the disclosed data code is expressed as “disclosed code” and the terminal identification code is expressed as “end terminal”.

  In the next step S123, processing for determining whether or not the above-mentioned predetermined flag is set to “1”, that is, whether or not confidential data is included, is performed. If secret data is included (if the flag is set to “1”: S123; Yes), the process proceeds to step S125, and if secret data is not included ( When the flag is set to “0”: S123; No), a series of concealment processing (S125 to S133) is skipped, and the process proceeds to step S135.

  Steps S <b> 125 to S <b> 133 are a series of confidential processing that is performed when confidential data is included in the print data. First, in step S125, a process of adding the secret identification code immediately after the termination identification code is performed.

  In the processing in step S125, the secret identification code is arranged immediately after the termination identification code, so that the data code arranged after the termination identification code is “coded as a code word representing the confidential data”. It expresses "something". 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 recognize that the QR code Q includes a secret data code. It is possible to prevent unintended data, garbled data, and the like from being mistakenly read as a secret data code, and to prevent malfunction caused by this.

  In the next step S127, 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 after the secret identification 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.

  For example, in the example shown in FIG. 3C, the sum of the data length of the secret data code α and the data length of the secret data code β is calculated as the data length and added immediately after the secret identification code. In FIG. 3C, 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 a succeeding step S129, 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 is received from the personal computer 1 in step S111, since there is an encryption key (S129; Yes), the process proceeds to step S131 and the encryption process is performed. On the other hand, if the encryption key has not been received from the personal computer 1 in step S111, there is no encryption key (S129; No), so the encryption process in step S131 is skipped and the process proceeds to step S133.

  Even if the encryption key has not been received in step S111, since 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 (S129; Yes). In step S131, encryption processing is performed.

  In step S131, 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 (D), 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 step S133, processing for adding a secret data code immediately after the data length is performed. In the example shown in FIG. 3D, the secret data code α and the secret data code β are added after the data length. As a result, in the two-dimensional code reader of the general specification, in the two-dimensional code decoding process, the padding code placed after the terminal identification code is not subject to reading, and thus, after the terminal identification code as described above. The arranged secret data code cannot be read. Therefore, even if a two-dimensional code including such a secret data code is read by a general-purpose reader, the existence of the secret data code is not known, so the user of the reader does not recognize the presence of the secret data. It becomes possible to do so.

  In the subsequent step S135, for example, in accordance with the processing algorithm described in the JIS basic specification (JIS X 0510: 2004), a process of adding a padding code after the secret data code is performed, and in step S137, further. Then, a process of adding an error correction code is performed. As a result, a data code having the format shown in FIG. 3C is generated.

  In step S139, each cell is generated on the basis of the data code generated in step S137, and processing for 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. 3C, the disclosed data code A is arranged in A0 to A2, the disclosed data code B is arranged in A3 to A6, and the terminal identification code is arranged in A7. Then, behind this termination identification code, a secret identification code, a data length, a secret identification code, and the like are usually arranged at A8 to A17 corresponding to positions where the padding code is arranged.

  That is, a secret identification code is arranged at A8, a data length is arranged at A9 thereafter, a secret data code α is arranged at A10 to A13, and a secret data code β is arranged at A14 to A17. 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 A18 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 S131, as shown in FIG. 3E, 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 S123 that confidential data is not included (if the flag is set to “0”: S123; No), as shown in FIG. A processing step for adding the “start digit” or “number of characters” added in step S131 before the plaintext data that has not been converted may be provided between step S123 and step S135. 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 secret data code is set as one of the padding codes in step S133. Instead of part or all, it is arranged after the end identification code. As a result, the secret data code placed after the terminal identification code is not subject to reading by a general-purpose reader, so a two-dimensional code including such a secret data code is read by a general-purpose reader. However, the existence of data to be concealed by the secret data code is not known. 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 a secret data code encoded as a code word representing data to be concealed is part or all of the padding code Instead of the terminal identification code, the two-dimensional code generation program is arranged after the terminal identification code. Lamb. "To be able to grasp that can be represented 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 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 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 , the 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 counter n 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.

  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 a terminal identification code (S305; Yes), the normal data code arranged before the terminal identification code is no longer included in the QR code Q. Therefore, the process proceeds to step S315.

  On the other hand, if it is not possible to determine that the data code is the termination identification code (S305; No), the normal data code still exists before the termination identification code, so the process proceeds to step S307. And the code number i is acquired for the next data code, that is, the (n + 1) th data code. As described with reference to FIG. 3D 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, the process of setting “n + i + 1” to the counter n is performed so that the counter n indicates the next data code, and then the process returns to step S303 to return to the nth The process of acquiring the data code is performed.

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. Therefore, the control circuit 40 or the like to perform each of these steps, which may correspond to "first decoding means."

  In step S315, a process of determining whether or not “1” is set in the predetermined flag, that is, whether or not the secret data code of the QR code Q is decrypted with the decryption key is performed. If “1” is not set in the flag (S315; No), it is not necessary to perform decryption with the decryption key. Therefore, the present decryption process is terminated and step S300 shown in FIG. 6 is terminated. End the process.

  On the other hand, if “1” is set in the predetermined flag (S315; Yes), it is necessary to decrypt with the decryption key. Therefore, the process proceeds to subsequent step S317 and n + 1 is set to the counter n. Further, in step S319, a process for obtaining the nth data code indicated by the counter n is performed.

In subsequent step S321, a process is performed to determine whether or not the nth data code acquired in step S319 is a secret identification code. Therefore, the control circuit 40 or the like to perform this step S321, may correspond to "data code determining means" and "secret identification code determination means".

  As a result, when it is determined that the data code is a secret identification code (S321; Yes), since the secret data code exists after the secret identification code, the process proceeds to the subsequent step S323. 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 S321 that the 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 secret identification code (S321; No), no more secret data code is included in the QR code Q after the secret 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 acquired in step S323, in the subsequent step S325, a process for acquiring the data code for the number of characters (j) is performed, and in step S327, the counter n indicates the next data code, that is, the secret data code. Thus, after the process of setting “n + j + 2” to the counter n is performed, the process of acquiring the nth decryption key check data (key specifying information) is performed in step S329.

  Then, based on the decryption key check data acquired in step S329, whether the decryption key received from the host computer HST in previous step S209 is suitable as a key for decrypting the encrypted data of the nth secret data code A determination of whether or not is made in step S331. 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, when it cannot be determined in step S331 that the decryption key is suitable (S331; No), the next secret data code is acquired without decrypting the nth secret data code. Therefore, the process proceeds to step S337 and n + 1 is set to the counter n. 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, the secret data code is decrypted based on the encrypted data decrypted in this step S335.

  When the decoding process in step S335 is completed, a process for setting “n + 1” to the counter n is performed in step S337 so that the count 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. As a result, if the nth data code is a padding code (S341; Yes), the QR code Q does not contain any more secret data code. The process is finished, and step S300 shown in FIG. 6 is finished, and the decoding process is finished.

  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 S323. , 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 S319 and S323 to S335, a process of obtaining and decoding a data code (second data code, secret data code) that is arranged behind the termination identification code and is not originally decoded is performed. Therefore, the control circuit 40 or the like to perform each of these steps may correspond to the "second decoding means."

As described above, according to the QR code reader 20 according to the present configuration , the secret data code (second data) is placed in the code area (empty part of the code area) after the terminal identification code where only the padding code is originally arranged. This secret data code can be decoded even if the (code) is arranged. 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. Therefore, the QR code Q printed by the QR code printer 10 described in the first embodiment can be decoded by the QR code reader 20 according to this configuration .

In the decoding process described above, the nth decryption key check data is obtained in step S329. For example, as described with reference to FIG. 3E 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 S329. 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 secret data code is encrypted with a different encryption key, if each decryption key is added to each secret data code, the nth decryption is performed instead of step S329. 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.

Further, in the decoding process described above, the n-th decryption key check data is obtained in step S329. 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. In this case, the control circuit 40 or the like for executing processing "separating" starting column "from secret data code" may correspond to "positional information separating means". In addition, the control circuit 40 or the like that executes a process of “placement of the secret data obtained by decoding (decoding) the secret data code based on the separated“ start digit ”in the positional relationship in the data record before being encoded” It may correspond to the "data arrangement means".

[Second Embodiment]
Next, another QR code generation process by the QR code printer 10 according to the second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 9 (C), the other QR code described here adopts a format in which an arbitrary code (for example, 00000000 or 11111111) is packed in an empty area instead of the padding code (11101100). .

  In the flowchart of the code generation process shown in FIG. 8, process steps that are substantially the same as the process steps that make up the already described code generation process (FIG. 2) are assigned the same reference numerals, and detailed description thereof is omitted. Similarly, for the data and code format examples shown in FIG. 9, detailed description of the format substantially the same as the format example (FIG. 3) already described is omitted. In FIG. 9, for the sake of convenience, the disclosed data code is expressed as “disclosed code”, and the terminal identification code is expressed as “end terminal”.

  As shown in FIG. 8, 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. When the initial setting process is performed in step S101, print data is received in step S103. To do. When the confidential data is received through steps S107 and S111, the disclosed data and the confidential data are rearranged in step S115, and each data such as the disclosed data and the confidential data is encoded in step S117, and then error correction is performed in step S119. A code is generated, and a terminal identification code is added after the disclosed data code in step S121.

  Instead of adding such a terminal identification code after the disclosed data code, for example, by calculating the data length of all disclosed data codes as in the format shown in parentheses in FIG. The end position data (in FIG. 9C, “end information”) that can identify the “end position of the code string formed by the disclosed data code” (hereinafter simply referred to as “end position”) is placed at the beginning of the disclosed data code. It may be added.

  If the secret data is included in the print data (S123; Yes), the secret data is added to the print data after adding the secret identification code after the end position in steps S125 to S133. If not (S123; No), for example, 00000000 or 11111111 is added as the above-mentioned arbitrary code after the end position in step S135 ′.

  That is, in the arbitrary code addition processing in step S135 ′, if an empty area (empty portion of the code area) is generated even if the secret data code is packed in the range after the end position and before the error correction code, Instead of the grass code, an arbitrary code (for example, 00000000 or 11111111) is packed. For this reason, for example, in the case where an initialization process in which the entire range is preliminarily filled with such an arbitrary code on the memory constituting such a data format in step S101, step S135 ′ is performed. It can be omitted without performing (in FIG. 8, the frame line of step S135 ′ is represented by a broken line).

  Then, when the process of adding an error correction code is performed in step S137, a data code having the format shown in FIG. 9C is generated. In subsequent step S139, each cell is changed based on such a data code. Generated and placed in the data block described with reference to FIG. In other words, the QR code is arranged in the same manner as the QR code described with reference to FIGS. 2 to 4 except that the arbitrary code described above is originally arranged in the range in which the padding code is arranged.

As described above, according to the QR code printer 10 according to the second embodiment, in the QR code Q generated by the code generation process executed by the MPU 11, the secret data code is arranged after the end position in step S133. ing. As a result, the secret data code arranged after the end position is not subject to reading by a general-purpose reader, so even if a two-dimensional code including such a secret data code is read by a general-purpose reader. The existence of data to be concealed by the secret data code is unknown. 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 second 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. 8 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, a termination 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, or the end position of the code string formed by the disclosed data code is specified. A secret data code that is a program for causing a computer to function as a two-dimensional code generation device that arranges possible end identification information at a predetermined position of the code string, and is coded as a code word representing secret data Of the termination position specified after the termination identification code or by the termination identification information. , Two-dimensional code generation program, characterized in that arranged in. "And can grasp representable technical idea. As a result, the computer functioning as a two-dimensional code generation device by this two-dimensional code generation program has the same operations and effects as the MPU 11 of the QR code printer 10 described above.

In the second 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 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, another QR code decoding process by the QR code reader 20 different from the above example will be described with reference to FIGS. The “other QR code” is a code that adopts a format in which an arbitrary code (for example, 00000000 or 11111111) is packed in an empty area instead of the padding code (11101100), and the QR according to the second embodiment. It is a QR code printed by the code printer 10.

  Note that, in the flowchart of the decoding process shown in FIG. 10, the processing steps that are substantially the same as the processing steps constituting the decoding process (FIG. 6) already described are assigned the same reference numerals and detailed description thereof is omitted. Also, in the flowchart of the decoding process shown in FIG. 11, processing steps that are substantially the same as the processing steps constituting the decoding process (FIG. 7) already described are assigned the same reference numerals and detailed description thereof is omitted.

  As shown in FIG. 10, 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. When the initial setting process is performed in step S201, a predetermined time has passed in step S205. After (S205; Yes) or after receiving the decryption key in step S209 (S209; Yes), image data is acquired in step S213. If the QR code Q is image-recognized in steps S215, S217, S219, and S221 and it is determined whether or not error correction is possible in step S223, and if it can be determined that error correction is possible (S223; OK). ) After error correction, the decoding process (FIG. 11) is performed in step S300 ′.

  As shown in FIG. 11, in the decoding process in step S300 ′, the end position (the end position of the code string formed by the disclosed data code, which can be specified by the end identification code or the end position data) in steps S301 to S313. If it is found (S305 ′; Yes), the nth data code pointed to by the counter n is acquired in steps S315, S317, and S319, and it is determined in step S321 whether or not it is a secret identification code. If it is determined that the code is a secret identification code (S321; Yes), the compatibility of the decryption key is checked in S323 to S331, the encrypted data is decrypted in S333 using the decryption key, and the secret data code is decrypted in step S335. .

  When it is determined in step S321 that the 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.

  In step S336 ', it is determined whether or not the decrypted secret data code is the last secret data code. Specifically, for example, as shown in FIG. 9 (C), since the data length of the subsequent secret data code is stored after the secret identifier, the secret data code is the last one based on this. It is determined whether it corresponds to the secret data code. In addition, as described above, after the last secret data code, that is, an arbitrary code (for example, 00000000 or 11111111) is packed in the empty area (the empty area of the code area). Based on the presence, it is determined whether or not the secret data code corresponds to the last secret data code.

  When it is not determined in step S336 ′ that the secret data code is the last secret data code (when it is determined that the secret data code is not the last secret data code) (S336 ′; No), the count n is set to the next count in step S337. After the process of setting “n + 1” in the counter n so as to indicate the data code is performed, the process of acquiring the nth data code is performed in the subsequent step S339, and the process of steps S323 to S331 is performed as described above. Check decryption key match.

  On the other hand, when it is determined in step S336 ′ that the secret data code is the last secret data code (S336 ′; Yes), the QR code Q further includes the secret data code. Therefore, the present decoding process is finished, step S300 ′ shown in FIG. 10 is finished, and the decoding process is finished.

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 end position and originally decoded is performed. Therefore, the control circuit 40 or the like to perform each of these steps, which may correspond to "first decoding means."

In step S321, processing for determining whether or not the nth data code acquired in step S319 is a secret identification code is performed. Therefore, the control circuit 40 or the like to perform this step S321, may correspond to "data code determining means" and "secret identification code determination means". Furthermore, the control circuit 40 or the like that executes steps S331 and S333 can correspond to a “key matching determination unit” or a “decryption unit”.

Further, in steps S319 and S323 to S335, a process of acquiring and decoding a data code (second data code, secret data code) that is arranged behind the end position and is not originally decoded is performed. Therefore, the control circuit 40 or the like to perform each of these steps, which may correspond to "second decoding means."

As described above, according to the QR code reader 20 , the secret data code (second data code) is arranged in the code area (empty part of the code area) after the end position where the data code is not arranged. Even 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. Therefore, the QR code Q printed by the QR code printer 10 can be decoded by the QR code reader 20 .

In the decoding process described above, the n-th decryption key check data is obtained in step S329. For example, as described with reference to FIG. 3E in the first embodiment, the second implementation is performed. Similarly, in the embodiment, when the decryption key itself is added to the secret data code (see FIG. 9E), the n-th decryption key may be obtained instead of step S329. good. 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 secret data code is encrypted with a different encryption key, if each decryption key is added to each secret data code, the nth decryption is performed instead of step S329. 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.

Further, in the decoding process described above, the n-th decryption key check data is obtained in step S329. For example, as described with reference to FIG. 3D in the first embodiment, the second implementation is performed. Similarly, in the form, when “start digit” as position information is added to the secret data code (see FIG. 9D), instead of this step S329, “start digit” is added from the secret data code. Separately, the secret data obtained by decoding (decoding) the secret data code based on the separated “start digit” 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. In this case, the control circuit 40 or the like for executing processing "separating" starting column "from secret data code" may correspond to "positional information separating means". In addition, the control circuit 40 or the like that executes a process of “placement of the secret data obtained by decoding (decoding) the secret data code based on the separated“ start digit ”in the positional relationship in the data record before being encoded” It may correspond to the "data arrangement means".

[ Third Embodiment]
Next, another QR code generation process by the QR code printer 10 according to the third embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 14B and the like, the other QR code described here adopts a format in which the secret data codes α, β, etc. are subjected to predetermined processing and are packed in the empty area.

  In the flowchart of the code generation process shown in FIG. 12, process steps that are substantially the same as the process steps constituting the code generation process (FIG. 2) already described are assigned the same reference numerals and detailed description thereof is omitted. Similarly, with respect to the code format example shown in FIG. 14, the detailed description of the format substantially the same as the format example (FIG. 3) already described is omitted. In FIG. 14, for the sake of convenience, the disclosed data code is expressed as “disclosed code”, and the terminal identification code is expressed as “end terminal”.

  As shown in FIG. 12, 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. When the initial setting process is performed in step S101, print data is received in step S103. To do. Then, when the confidential data is received through steps S107 and S111, each data such as the disclosed data and the confidential data is encoded in step S117, and then the termination identification code or the like (the disclosed data code is changed after the disclosed data code in step S121 ′). Including the end position of the code string to be formed).

  If the print data includes secret data (S123; Yes), after adding a secret identification code following the end position in steps S125 and S127, the secret data code is encrypted in step S131. In step S132, a padding code is added to the empty area. Thereafter, predetermined processing in step S500 is performed. On the other hand, when the secret data is not included in the print data (S123; No), the process proceeds to step S133 without performing these processes (S125, S127, S131, S132, S500).

  Here, the predetermined processing in step S500 will be described with reference to FIG. As shown in FIG. 13, in the predetermined processing, first, a process of clearing the pointer i to zero is performed in step S501. This pointer i indicates the bit position to be subjected to the distributed arrangement processing in steps S507 to S517, and starts from the 0th bit by this clear processing.

  In step S503, the number of bits n in an empty area existing after the end position (see FIGS. 14A to 14C), that is, an area that is originally filled with padding code and excluding the error correction code range n. Is obtained. This process is a constant used when the pseudo random number R is obtained in step S513 described later.

  In subsequent step S505, a process for obtaining the sum m (see FIGS. 14D and 14E) of the number of bits of the encrypted data and the number of bits of the decryption key check data is performed. That is, by determining the number of bits of the secret data code that is the target of the distributed arrangement process, it is possible to determine whether or not the distributed arrangement can be completed in step S519 described later.

  In the next step S507, an exclusive OR (EXOR) operation is performed on the disclosed data code and the encrypted data in units of 2 bytes, and the result S is obtained. In the subsequent step S509, such an operation result S is obtained. Processing for setting the seed value of the pseudo random number in step S513 is performed. This seed value is a seed for generating a pseudo-random number by a predetermined calculation. If this seed value is the same, the generated random number is exactly the same. That is, the pseudo-random number in step S513 is uniquely determined by the value of the calculation result S and the order of generation. In this respect, this processing is performed based on the content of the disclosed data code.

  In step S511, a process of incrementing the pointer i, ie, counting up by 1, is performed. As a result, the count of the bit position (position pointed by the pointer i) to be subjected to the distributed arrangement processing in step S517 or the like is increased. In the previous example, counting up from 0 to 1 points to the first bit.

  In the subsequent step S513, a process for obtaining the pseudo random number R is performed. This operation is to generate a pseudo random number by performing information processing according to a predetermined random number generation algorithm based on the seed value described above. Here, 1 to n (n is a bit in a free area) Pseudo-random numbers are generated in the range up to (number). For this reason, for example, it is calculated by an arithmetic expression “R = rand () mod n + 1”.

  Note that rand () is a function that returns a pseudo-random number for the seed value S, and x mod y is a function that calculates a modulo value y for x. That is, in the previous arithmetic expression, 1 is added to the remainder when the value of the pseudo random number that is the argument x (that is, rand ()) before mod is divided by the argument y that is after mod (n). As a value, a pseudo random number R is obtained. Note that n is the number of bits in the free area as described above.

  When the pseudo-random numbers R from 1 to n are obtained in step S513 in this way, the next step S515 determines whether or not the pseudo-random numbers R have already been generated. That is, when the same value is generated as the pseudo random number R, the bit value is overwritten in the rearrangement process in the next step S517, so that the value previously arranged at the same bit position is prevented from being destroyed. It is to do. For this reason, if it is determined in step S515 that the same value has already been generated as the pseudorandom number R (S515; Yes), the process returns to step S513 to obtain the pseudorandom number R again.

  If it is not determined in step S515 that the value is the same as the pseudorandom number R that has already been generated (S515; No), the value of the i-th bit (the position of the bit pointed to by the pointer i) of the encrypted data is made empty in the subsequent step S517. Processing to set the R bit in the region, that is, placement processing is performed. In the previous example, the value of the first bit is set to the R bit of the empty area. As a result, the information originally located at the first bit moves to the R bit generated irregularly by the random number.

  In the subsequent step S519, a process for determining whether or not the value of the pointer i has reached the end (last bit) of the number of bits of the secret data code that is the target of the distributed arrangement process, that is, whether or not the distributed arrangement has been completed is determined. Is called. When the pointer i matches the total number of bits of the secret data code, all the bits of the secret data code have been subjected to the distributed arrangement processing in steps S507 to S517 described above ( S519; Yes), this processing ends.

  On the other hand, when the pointer i and the total number of bits of the secret data code do not match, the bits that have not yet been distributed and arranged remain in the secret data code (S519; No), the pointer i is counted up in step S511, and the pseudo-random number generation process in step S513 is performed again.

  Thus, by repeating the processing in steps S513 to S517 for all the bits of the secret data code, the first bit, the second bit, the third bit,..., The (n−1) th bit, the n bit Each piece of bit information arranged in order, such as an eye, moves to the position corresponding to the random number R that fluctuates irregularly. Therefore, when the predetermined processing process in step S500 is completed, for example, as shown in FIG. 14B, the secret data codes α and β (FIG. 14A) before the distributed arrangement process is performed. Both are disassembled in bit units and distributed and rearranged as confidential data code fragments, and the padded grass code is also disassembled into bits in the same manner by distributed allocation processing. In this state, it is rearranged in the free area.

  As a result, the encrypted secret data code is further scrambled, so that the security can be further enhanced.

  In this processing, instead of such distributed arrangement processing in steps S507 to S517, for example, bit rearrangement based on a bit position conversion table (conversion table) that can convert bit positions may be used. Specifically, for example, the 1st bit is the 4th bit, the 2nd bit is the 13th bit, the 3rd bit is the 1st bit, the 4th bit is the 2nd bit, the 5th bit is the 15th bit 6th bit to 11th bit, 7th bit to 8th bit, 8th bit to 3rd bit, 9th bit to 10th bit, 10th bit to 6th bit, 11th bit To the 12th bit, 12th bit to 5th bit, 13th bit to 9th bit, 14th bit to 16th bit, 15th bit to 7th bit, 16th bit to 14th bit Each bit position conversion table for converting the position is provided to convert the bit position according to the conversion rule. Thereby, for example, data “1001011011010110” (96D6h) having a 16-bit configuration is converted into “0101101101100001” (5A61h).

  In addition, by passing through such a bit position conversion table, for example, in the above example, the data “96D6h” in hexadecimal notation is converted to “5A61h”, so that it is specified by the bits constituting the secret data code. It can be grasped as a technical idea that the data value itself is converted based on a predetermined data value conversion table (conversion table). This data value conversion can also be performed by a predetermined data value conversion formula, for example, by doubling the input data X and subtracting 1 to output Y (= X × 2-1).

Further, for example, a cyclic shift register may be used so that the bit position is cyclically shifted to the LSB side by a predetermined number of bits. In the previous 16-bit data example, “1001011011010110” (96D6h) is converted to “0110100101101101” (696Dh). Of course, the shift amount is not limited to 4 bits. In the case of a 16-bit configuration, any of 1 to 15 bits may be used, and the shift direction may be on the MSB side. Note that the 16 bits of the 16-bit configuration illustrated here correspond to the sum m of the number of bits of the encrypted data and the number of bits of the decryption key check data described above. FIG. 14 (D) shows a format example (encrypted data + decryption key check data) based on bit rearrangement and bit value conversion other than the above-described distributed arrangement processing (FIG. 14 (D)). E) is a configuration example of a secret code generated by the code generation process of the second embodiment as a comparison.

  In step S507, the disclosed data code and the encrypted data are subjected to an exclusive OR (EXOR) operation in units of 2 bytes to obtain a result S, which is set as a pseudorandom seed value in step S509. However, in place of the disclosed data code, the encrypted data is exclusive using unique information accompanying the QR code Q, for example, error correction level (L, M, Q, H) or model number (1-40). A logical sum (EXOR) operation may be performed to obtain S as a result. The details and specifications of the error correction level and model number conform to, for example, the Japanese Industrial Standard (JIS) two-dimensional code symbol-QR code-basic specification (JIS X 0510: 2004).

  Returning to FIG. 12, after the predetermined processing process is completed in step S500, a secret data code is added in the subsequent step S133, and further, it is determined whether or not a secret data code is included in step S134. Processing is performed.

  That is, in step S134, if a secret data code is included (S134; Yes), since the padding code has already been added in step S132 described above, the padding code is added in the subsequent step S135. It becomes unnecessary. For this reason, in such a case, the process by step S135 is skipped and the process proceeds to step S137. On the other hand, if the secret data code is not included, that is, only the disclosed data code (S134; No), the padding code is not added yet, so the padding code is added in the subsequent step S135. Then, the process proceeds to step S137.

  Then, when the process of adding an error correction code is performed in step S137, a data code having the format shown in FIGS. 14A to 14C is generated. Based on such a data code in subsequent step S139. Each cell is generated and arranged in the data block described with reference to FIG.

As described above, according to the QR code printer 10 according to the third embodiment, the QR code Q generated by the code generation process executed by the MPU 11 performs predetermined processing on the secret data code by the processing process in step S500. And placed after the termination identification code or after the termination position specified by the termination identification information. As a result, the secret data code has been processed in a predetermined manner so that the existence of the secret data code is not known, so even if an attempt is made to read after the end identification code, the secret data code Since it is not even known that it is arranged, the strength of security can be further increased.

In the third embodiment described above, the process of rearranging the disclosed data and the confidential data (corresponding to S115 shown in FIG. 2) is not interposed after step S113, but the data disclosed to the third party in the print data. (Disclosure data) and data (secret data) that the third party wants to keep secret and concealed are included, and when these are mixed in the data record, “ Based on the “positional information indicating the positional relationship in the data record of the confidential data”, the order of the data may be switched to perform a process of dividing into a collection of disclosed data and a collection of confidential data. Thereby, for example, when the print data record sent from the personal computer 1 includes data arranged in the order of the disclosed data A, the confidential data α, the disclosed data B, and the confidential data β, the process proceeds to step S115. By performing the process of rearranging the disclosed data A, the disclosed data B, the secret data α, and the secret data β in this order, the disclosed data and the secret data are collected, respectively. The process of adding a secret identification code in step S125 is facilitated.

Next, another QR code decoding process by the QR code reader 20 different from the above example will be described with reference to FIGS. The other QR codes described here adopt a format in which the secret data codes α, β, etc. are subjected to predetermined processing and packed into an empty area as described above with reference to FIG. is there.

  In the decoding process flowchart shown in FIG. 15, processing steps that are substantially the same as the processing steps that constitute the decoding process (FIG. 10) that has already been described are assigned the same reference numerals, and detailed descriptions thereof are omitted. Also, in the flowchart of the decoding process shown in FIG. 16, the processing steps that are substantially the same as the processing steps constituting the decoding process (FIG. 11) already described are assigned the same reference numerals and detailed description thereof is omitted.

  As shown in FIG. 15, 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. When the initial setting process is performed in step S201, a predetermined time has passed in step S205. After (S205; Yes) or after receiving the decryption key in step S209 (S209; Yes), image data is acquired in step S213. If the QR code Q is image-recognized in steps S215, S217, S219, and S221 and it is determined whether or not error correction is possible in step S223, and if it can be determined that error correction is possible (S223; OK). ) After error correction, the decoding process (FIG. 16) is performed in step S300 ″.

  As shown in FIG. 16, in the decoding process of step S300 ″, the end position (the end position of the code string formed by the disclosed data code, which can be specified by the end identification code or the end position data) in steps S301 to S313. If found (S305 ′; Yes), the nth data code pointed to by the counter n is obtained in steps S315, S317, and S319, and it is determined whether or not it is a secret identification code in step S321. If it is determined that it is a code (S321; Yes), the number j of codes is acquired in the subsequent step S323, and then a predetermined extraction process in step S600 is performed.

  When it is determined in step S321 that the 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.

Here, the predetermined extraction process in step S600 will be described with reference to FIG. The predetermined extraction process shown in FIG. 17 is similar in content to the predetermined processing (FIG. 13) already described in the third embodiment, so that the processing steps constituting the predetermined processing are Substantially the same processing steps are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 17, in the predetermined extraction process, the pointer i is cleared to zero in step S501, and the number of bits n in the empty area existing after the end position in step S503 (see FIGS. 14A to 14C). ) For obtaining the sum m (see FIGS. 14D and 14E) of the number of bits of the encrypted data and the number of bits of the decryption key check data in step S505, and the disclosed data code and encryption in step S507 A process of performing an exclusive OR (EXOR) operation on the digitized data in units of 2 bytes and obtaining the result S is sequentially performed, and a process of setting the seed value of the pseudo random number is performed in subsequent step S509.

As described in the third embodiment, the seed value set in step S509 is a seed for generating a pseudo-random number by a predetermined operation. If this seed value is the same, the generated random number is not at all. It will be the same. For this reason, if the QR code Q is the same, the seed value of the predetermined processing (FIG. 13) and the seed value of the main extraction process are the same value, and the value of the pseudo random number and the generation order thereof in the next step S513. Will be the same.

  If the process of obtaining the pseudo random number R is performed in step S513 and it is not determined that the value is the same as the pseudo random number R that has already been generated in step S515 (S515; No), the R bit of the free area is determined in the subsequent step S617. Is set to the i-th bit (bit position indicated by the pointer i) of the encrypted data buffer.

That is, in the predetermined processing of the third embodiment, in step S517, the value of the i-th bit (the position of the bit pointed by the pointer i) of the encrypted data is set to the R-bit of the empty area. For example, although the value of the first bit is set to the R bit of the free area, in step S617 of this extraction process, on the contrary, the value of the R bit of the free area is set to the i bit of the encrypted data buffer. For example, the R bit value of the empty area is set to the first bit of the encrypted data buffer.

As a result, the i-th bit value of the encrypted data set in the R bit of the empty area by the predetermined processing of the third embodiment is set in the i-th bit of the encrypted data buffer by this extraction process. Therefore, it is possible to restore the secret data code pieces and the like that have been disassembled separately in bit units. That is, in step S617 and the like, the aggregate restoration process can be performed.

  If it is determined in step S519 that the pointer i matches the total number of bits of the secret data code, all the bits of the secret data code have been subjected to the aggregation restoration process in steps S507 to 517 described above. (S519; Yes), the present processing is terminated. On the other hand, when the pointer i and the total number of bits of the secret data code do not match, the bits that have not yet been restored remain in the secret data code (S519; No). ), The pointer i is counted up in step S511, and the pseudo-random number generation process in step S513 is performed again.

  Returning to FIG. 16, after the predetermined extraction process is completed in step S600, the data code is acquired for the number of characters (j) in step S325, and the j-th decryption key check data (key key) is acquired in the subsequent step S329 ′. Specific information).

  Then, based on the decryption key check data acquired in step S329 ′, whether the decryption key received from the host computer HST in previous step S209 is suitable as a key for decrypting the encrypted data of the j-th secret data code It is determined whether or not the decryption key is suitable (S331; Yes), and the encrypted data is decrypted in the subsequent step S333.

  On the other hand, if it cannot be determined in step S331 that the decryption key is compatible (S331; No), the decryption process is terminated without decrypting the n-th secret data code. When the process of decoding the secret data code is performed in step S335, step S300 ″ shown in FIG. 15 is finished and the decoding process is ended.

In this extraction process, for example, bit rearrangement based on a bit position reverse conversion table that can convert bit positions in the reverse direction may be used instead of the aggregation restoration process in steps S507 to S617. Specifically, for example, in the bit position inverse conversion table described in the third embodiment, the first bit is the third bit, the second bit is the fourth bit, the third bit is the fourth bit, 5th bit to 12th bit, 6th bit to 10th bit, 7th bit to 15th bit, 8th bit to 7th bit, 9th bit to 13th bit The 10th bit is the 9th bit, the 11th bit is the 6th bit, the 12th bit is the 11th bit, the 13th bit is the 2nd bit, the 14th bit is the 16th bit, 15th bit A bit position reverse conversion table for converting the position is provided for the 5th bit and the 16th bit to the 14th bit, and the bit position is converted according to the reverse conversion rule. Thereby, for example, data “0101101101100001” (5A61h) having a 16-bit configuration is converted into the original “1001011011010110” (96D6h).

Further, instead of passing such a bit position reverse conversion table, a data value reverse conversion table capable of converting the data value specified by the bits constituting the secret data code in the reverse direction may be used. For example, in the example of the data value conversion table described in the third embodiment, the data “96D6h” in hexadecimal notation is converted to “5A61h”, so that “5A61h” in the reverse direction is converted to “96D6h”. By performing conversion based on a predetermined data value reverse conversion table that can be converted back to, restoration processing can be performed.

Further, instead of passing through such a bit position reverse conversion table, a data value reverse conversion formula capable of converting the data value specified by the bits constituting the secret data code in the reverse direction may be used. For example, in the example of the predetermined data value conversion formula described in the third embodiment, the input data X is doubled and then 1 is subtracted to output Y (= X × 2-1). On the other hand, the result of adding 1 to the input data X ′ is divided by 2 and output Y ′ (= (X ′ + 1) / 2), thereby enabling restoration processing.

Furthermore, when the cyclic shift register described in the third embodiment is passed, the restoration process can be performed by using the cyclic shift register that shifts in the direction opposite to the predetermined processing process for the restoration process. For example, in the above 16-bit data example, “1001011011010110” (96D6h) is converted to “0110100101101101” (696Dh) by shifting 4 bits to the LSB side in a predetermined processing process. By shifting 4 bits to the MSB side in the reverse direction, it becomes possible to return to the original state such as “1001011011010110” (96D6h).

As for the seed value of the pseudo random number set in step S509, as in the third embodiment, unique information associated with the QR code Q, such as an error correction level (L, M, Q, H) or model number, is used. (1-40) may be used to perform an exclusive OR (EXOR) operation on the encrypted data and the result S may be obtained. The details and specifications of the error correction level and model number conform to, for example, the Japanese Industrial Standard (JIS) two-dimensional code symbol-QR code-basic specification (JIS X 0510: 2004).

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 end position and originally decoded is performed. Therefore, the control circuit 40 or the like to perform each of these steps, which may correspond to "first decoding means."

In step S321, processing for determining whether or not the nth data code acquired in step S319 is a secret identification code is performed. Therefore, the control circuit 40 or the like to perform this step S321, may correspond to "data code determining means" and "secret identification code determination means". Furthermore, the control circuit 40 or the like that executes Step S333 can correspond to “decoding means”.

Further, in steps S319 and S323 to S335, a process of acquiring and decoding a data code (second data code, secret data code) that is arranged behind the end position and is not originally decoded is performed. Therefore, the control circuit 40 or the like to perform each of these steps, which may correspond to "second decoding means."

As described above, according to the QR code reader 20 of this configuration, the secret data in which the predetermined processing is performed on the code area (empty part of the code area) after the termination identification code where the data code is not originally arranged. Even if a code (second data code) is arranged, the second 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.

In the decoding process described above, the j-th decryption key check data is acquired in step S329 ′. For example, as described in the third embodiment, after step S113, disclosed data and confidential data are acquired. The order of the data is changed based on the “positional information indicating the positional relationship in the data record of the confidential data” received in step S111 through the process of rearranging the data (corresponding to S115 shown in FIG. 2). In the case where the process of dividing into a group of secret data and a group of secret data is performed, instead of step S329 ′, the “start digit” is separated from the secret data code and the secret data is based on the separated “start digit”. Even if the secret data obtained by decoding (decoding) the code is arranged in the positional relationship in the data record before being encoded, There.

  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. In this case, the control circuit 40 or the like that executes the process of “separating the“ start digit ”from the secret data code” may correspond to “position information separating means”. In addition, the control circuit 40 or the like that executes a process of “placement of the secret data obtained by decoding (decoding) the secret data code based on the separated“ start digit ”in the positional relationship in the data record before being encoded” May correspond to “data arrangement means”.

Next, QR code Q decoding processing by the QR code reader 20 different from the above example will be described with reference to FIGS. The QR code Q described here means a QR code including each secret data code described in the first to third embodiments.

Note that although the flowchart of the decoding process is not shown here, the decoding processes in steps S300, S300 ′, and S300 ″ shown in FIGS. 6, 10, and 15 are replaced with the decoding processes shown in FIG. 18 can be applied to this configuration, and in the flowchart of the decoding process shown in Fig. 18, the processing steps that are substantially the same as the processing steps that constitute the decoding processing (Fig. 11) already described. Are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 18, the decoding process determines that the end position is not the end position (the end position of the code string formed by the disclosed data code, which can be specified by the end identification code or the end position data) (S305 ′). No), after obtaining the data code for the number of characters i in steps S307 and S309, it is determined whether or not to decode the disclosed data code in step S310.

  That is, in this step S310, the state of “read flag S” described later with reference to FIG. 19 ((1) flag S = 1 for decoding only the disclosed data code, (2) decoding only the secret data code. Flag S = 2, (3) flag S = 0 for data coding of both the disclosed data code and the secret data code), whether or not the information for decoding the disclosed data code is set in the reading flag S to decide. This reading flag S is set, for example, in a predetermined area or register of the memory 35 constituting the QR code reader 20, and is set by a reading flag setting process (see FIG. 19) described later.

  (1) When the flag S = 1 for decoding only the disclosed data code or (3) The flag S = 0 for data encoding both the disclosed data code and the confidential data code is set in the reading flag) (S310; Yes), the process of decoding the disclosed data code is performed in the following step S311. (2) When the flag S = 2 for decoding only the secret data code is set in the reading flag (S310; No) Then, the process of decoding the disclosed data code is skipped in the subsequent step S311, and the process of acquiring the next data code is performed in steps S313, S303 and the like.

  On the other hand, when the end position (the end position of the code string formed by the disclosed data code, which can be specified by the end identification code or the end position data) is found in steps S301 to S313 (S305 ′; Yes), the confidential data is determined in step S314. Determine whether to decode the code.

  That is, in step S314, contrary to step S310 described above, it is determined based on the read flag S whether or not the secret data code is to be decoded. In other words, when (2) the flag S = 2 for decoding only the secret data code or (3) the flag S = 0 for data encoding both the disclosed data code and the secret data code is set in the reading flag ( (S314; Yes), the process of decoding the secret data code is performed in the following steps S315 to S335. (1) When the flag S = 1 for decoding only the disclosed data code is set in the reading flag (S314; No) ), This decoding process is terminated.

  Here, the reading flag setting process will be described with reference to FIG. The reading flag setting process is performed by changing, canceling, or initializing various setting states (for example, on / off of a beep sound, on / off of the backlight of the liquid crystal display 46, etc.) of the hardware constituting the QR code reader 20, for example. It is included in the maintenance program that is activated in the case of conversion, and is not included in the normal decoding process (FIGS. 6, 10, and 15). Here, the flowchart of the maintenance process by the maintenance program and the description thereof are omitted.

  As shown in FIG. 19, in the reading flag setting process, first, a predetermined initialization process such as setting the reading flag S to 0 (S = 0) is performed in step S901, and then the timer value is cleared in step S903. Processing is performed. This timer is counted to determine whether or not a predetermined time has passed in the next step S905.

  If it is determined in step S905 that the predetermined time has not elapsed (S905; No), processing is performed to determine whether or not a command has been received in subsequent step S907. For example, this command is received from the host computer HST or input from the operation switch 42 constituting the QR code reader 20 in the above-described maintenance program.

  If it is not determined at step S907 that the command has been received (it is determined that it has not been received) (S907; No), it is determined again at step S905 whether the predetermined time has elapsed. On the other hand, when it is determined that a command has been received (S907; Yes), processing for determining the content of the received command is performed in the subsequent step S909.

  That is, if the command is to decode only the disclosed data code (1) in step S909, “1” is set to the reading flag S in step S911 (S = 1), and the command is (2 If only the secret data code is to be decoded, “2” is set to the reading flag S in step S913 (S = 2). On the other hand, if the command is none of these, the reading flag S is kept “0” and the reading flag setting process is terminated. In other words, in this case, “0” set by default in step S901 described above is used as it is, and (3) the reading flag S for data coding of both the disclosed data code and the secret data code is maintained.

When the reading flag is set in steps S911 and S913, the reading flag setting process is terminated. Note that steps S310, S314 is may correspond to "decode function selection means". Further, step S311 may correspond to “decoding function of first data code”, and step S335 may correspond to “decoding function of second data code”.

As described above, according to the QR code reader 20 according to this configuration , the user of the QR code reader 20 selects at least one of decoding the disclosed data code or the confidential data code. For example, if you do not want to read the disclosed data code even if you read the confidential data code, or conversely, if you do not want to read the confidential data code even if you read the disclosed data code, the decoding time by unnecessary decoding processing Can be reduced. Therefore, the decoding time can be shortened.

In the above-described embodiments, for example, as described in the first embodiment (FIG. 2) or the second embodiment (FIG. 8), an error correction code is generated in step S119 of the code generation process. However, it is not always necessary to generate an error correction code in step S119. For example, a process corresponding to step S119 (error correction code generation process) is performed together with a process of adding an error correction code (step S137) or The flow of code generation processing may be configured to be executed at the previous stage.

1 ... PC 10 ... QR code printer 11 ... MPU
12 ... Memory 20 ... QR code reader (two-dimensional code reader)
35. Memory (first decoding means, data code judgment means, second decoding means, secret identification code judgment means, secret information output means, decryption means, key matching judgment means, key separation means, position information separation means, data arrangement means Extraction means, decoding function selection means)
40 ... Control circuit (first decoding means, data code judging means, second decoding means, secret identification code judging means, secret information output means, decoding means, key matching judgment means, key separating means, position information separating means, data arrangement Means, extraction means, decoding function selection 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 arranges a padding code that does not represent data in an empty portion of the code area. A program for
  A program for generating 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.   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,
  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.

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