JP4656050B2 - Document management system, printing device, document management device, program - Google Patents

Description

  The present invention relates to a document management system, and more particularly to distribution management of a document to be copied.

  In recent years, it is common to copy and use a document, but document history management has been emphasized from the viewpoint of improving copy quality and security. For example, in order to prevent unauthorized copying of a document, there is a method using a paper fingerprint. For example, the paper fingerprint of the paper medium on which the image data of the document is to be printed is acquired, the paper fingerprint and the paper medium ID are registered in the management server, and the paper medium ID is encoded into, for example, a QR code or the like. Print on paper media with image data. The paper fingerprint can identify the paper medium by using the randomness of the entanglement of the fibrous material of the paper medium (for example, Patent Documents 1 and 2). When the paper medium is used for copying, the paper fingerprint acquired by imaging the paper medium itself is collated with the paper fingerprint acquired from the management server based on the QR code of the paper medium. Thus, by verifying a paper medium when a document is copied, it is possible to manage the history of the document created by copying, prevent unauthorized copying of the document, and the like.

  Conventional techniques for embedding information in a paper medium to determine the validity of the paper medium and preventing information leakage by unauthorized copying include, for example, Patent Documents 2 to 4.

JP 2006-18525 A JP 2000-001031 A JP 2006-072707 A Japanese Patent Application Laid-Open No. 07-254038

  However, conventionally, in order to confirm the history of a document that has been copied several times, it has been necessary to make an inquiry to a server that manages the document history. That is, when a paper document is obtained, the history of the paper document cannot be confirmed on the paper.

  An object of the present invention is to make it possible to grasp a history of a document from a paper medium.

  In order to achieve the above object, a document management system according to the present invention includes a first reading unit that reads a first paper document, and a first paper document that is read by the first reading unit. An image pickup means for picking up an image of the paper surface of the second paper document created by printing the image data, and encoding information specific to the paper fingerprint obtained from the image data of the paper surface picked up by the image pickup means Generation processing means for generating code data, and first detection means for detecting code data of paper fingerprint identification information printed on the first paper document by analyzing the read image data of the first paper document And an unreadable processing means for performing data processing on the code data detected by the first detecting means in an unreadable state in a recoverable state, and unreadable by the unreadable processing means. Printing means for creating a second paper document by adding the code data generated by the generating means to the image data of the first paper document including code data that has been processed, and the printing means Code data of paper fingerprint identification information printed on the second paper document by analyzing the image data of the read second paper document, the second reading means for reading the second paper document created by A second detection means for detecting the code data, a legibility enabling processing means for restoring the code data that has been unreadable from the code data detected by the second detection means to be legible, and legible Output means for outputting information relating to the paper fingerprint based on the paper fingerprint identification information obtained from the code data.

  Storage means for storing paper fingerprint registration information; registration means for registering information related to paper fingerprint obtained from imaging data of the paper surface imaged by the imaging means to the storage means as paper fingerprint registration information; Acquisition means for acquiring paper fingerprint registration information from the storage means based on paper fingerprint identification information obtained from the code data made readable, and the output means outputs the information acquired by the acquisition means It is characterized by that.

  Further, the image processing apparatus has means for holding image data used in common for the data processing processing by the illegible processing means and the restoration processing by the readable processing means, or designating a method to be used in common. .

  The printing apparatus according to the present invention includes an imaging unit that images a paper surface of a second paper document created by printing image data of a first paper document, and a paper surface imaged by the imaging unit. Generation processing means for generating code data by encoding paper fingerprint specific information obtained from imaged data, and paper printed on the first paper document by analyzing the read image data of the first paper document First detection means for detecting code data of fingerprint identification information, and illegible processing means for performing data processing on the code data detected by the first detection means in an unreadable state in a recoverable state And adding the code data generated by the generating means to the image data of the first paper document including the code data processed indecipherable by the unreadable processing means. And having a printing means for creating a second paper document in Rukoto.

  Further, the illegibility processing means performs data processing for synthesizing mask image data with code data.

  The illegible processing means performs a data processing process for painting the code data with a color other than the color constituting the code data.

  The illegible processing means performs data processing for adding dots of a drawing unit smaller than the drawing unit of the code data to the code data.

  Further, the illegibility processing means performs a data processing process for inverting the mirror image of the code data.

  A document management apparatus according to the present invention includes a reading unit that reads a paper document printed using the above-described printing apparatus, and paper fingerprint identification information printed on the paper document by analyzing image data of the read paper document. Detection means for detecting the code data, readable processing means for recovering the readable code data of the code data detected by the detection means, and the readable code data Output means for outputting information relating to the paper fingerprint based on the paper fingerprint identification information obtained from the above.

  A program according to the present invention is obtained from imaging data of a captured paper surface by causing a computer to image the paper surface of a second paper document created by printing image data of the first paper document. The code information is generated by encoding the specific information of the paper fingerprint, and the code data of the paper fingerprint specific information printed on the first paper document is detected by analyzing the image data of the read first paper document. The detected code data is subjected to data processing in an unreadable manner in a recoverable state, and the generated code is generated in the image data of the first paper document including the code data processed in an unreadable manner. A second paper document is created by adding data and printing.

  The program according to the present invention causes a computer to read a paper document printed by executing the program, and analyzes the image data of the read paper document, thereby identifying the paper fingerprint identification information printed on the paper document. Information on paper fingerprints based on the paper fingerprint identification information obtained from the code data that can be read and restored to be readable. Is output.

  According to the present invention, when a paper document is copied to create a new paper document, the code data of the paper fingerprint identification information added to the paper document as the copy source is processed without being deleted, When verifying a newly copied paper document, the unreadable code data is restored to the readable code data, so that the history about the document is obtained from the paper document at hand. be able to.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block configuration diagram showing an embodiment of a document management system according to the present invention. FIG. 1 shows a system configuration in which a network scanner 1, a network printer 2, a multifunction machine 3, a client PC 4, a DBMS server 5, and a processing information management server 6 are connected to a network 7. The client PC 4 is a personal computer in which a user instructs the network scanner 1 and the multifunction machine 3 to print a document. While the network scanner 1 is a network device having a scanner function and the network printer 2 has a printing function, the multifunction device 3 is a multifunction copier having at least a scanner function and a printing function. The DBMS server 5 is a server computer equipped with a DBMS (DataBase Management System), and holds and manages information related to paper fingerprints. As will be described in detail later, in this embodiment, the QR code embedded in the paper document is processed so that it can be restored and cannot be read, but the processing information management server 6 uses the QR code data in this system. Data such as mask images used in common for processing is held and managed.

  A plurality of network scanners 1, network printers 2, multifunction devices 3, and client PCs 4 can be connected to the network 7, but each has the same function. The tables are shown one by one.

  FIG. 2 is a hardware configuration diagram of a computer included in the document management system according to the present embodiment. Although the performance and capacity of each component differ depending on the purpose of use, in this embodiment, the client PC 4, the DBMS server 5, and the processing information management server 6 correspond to this configuration. As shown in FIG. 2, the computer includes a CPU 11, ROM 12, RAM 13, HDD controller 15 connected to a hard disk drive (HDD) 14, a mouse 16 and keyboard 17 provided as input means, and a display 18 provided as a display device. Are connected to an internal bus 21 by an input / output controller 19 and a network controller 20 provided as communication means.

  FIG. 3 is a hardware configuration diagram of the MFP 3 according to the present embodiment. The multifunction machine 3 is a form of an image forming apparatus equipped with various functions such as a copy function and a scanner function as described above, and is an apparatus incorporating a computer. In FIG. 3, the CPU 31 controls the operation of various mechanisms mounted on the apparatus such as the scanner 34 and the printer engine 36 in accordance with a program stored in the ROM 39. The address data bus 32 is connected to various mechanisms to be controlled by the CPU 31 to perform data communication. The operation panel 33 receives instructions from the user and displays information. The scanner 34 reads a document set by a user and stores it as electronic data in an HDD (Hard Disk Drive) 35 or the like. The HDD 35 stores an electronic document read using the scanner 34. The printer engine 36 prints an image on output paper in accordance with an instruction from a control program executed by the CPU 31. The network interface (I / F) 37 is connected to a network and is used for transmitting paper fingerprint registration information to the DBMS server 5 and receiving processing information from the processing information management server 6. A random access memory (RAM) 38 is used as a work memory during program execution and a communication buffer during electronic data transmission / reception. A read only memory (ROM) 39 stores various programs such as control of this apparatus. By executing various programs, each component described later exhibits a predetermined processing function. An external media interface (I / F) 40 is an interface with an external memory device such as a USB memory or a flash memory.

  FIG. 4 is a block configuration diagram of a printing function processing unit that executes a printing function and a copying function processing unit that executes a copying function according to the present embodiment. The print function processing unit 50 generally prints corresponding document data in response to a print instruction sent from the client PC 4 or the like. The copy function processing unit 60 generally reads a paper document with a scanner in accordance with a copy instruction, generates image data, and executes printing of the generated image data. The printing function processing unit 50 and the copying function processing unit 60 are common in that they have a function of printing out electronic document data on a paper medium. However, the printing function processing unit 50 is the network printer 2 or the multifunction device 3 described above. It is realized with. Further, the copy function processing unit 60 can be realized by printing the image data read by the network scanner 1 or the multifunction device 3 by the network printer 2 or the multifunction device 3, but in the present embodiment, for convenience of explanation. Therefore, description will be made on the assumption that the copy function processing unit 60 is realized by the multifunction machine 3 having both the scanner function and the print function.

  The print function processing unit 50 includes a print request receiving unit 51, an imaging unit 52, a QR code generation unit 53, a synthesis unit 54, and a print execution unit 55. The print request reception unit 51 receives a print request including document data to be printed sent from the client PC 4. Although not shown in the configuration diagram described above, a CCD camera, for example, is attached as an image pickup unit in the vicinity of the paper tray carry-out port of the network printer 2 and the multifunction machine 3, and is carried out from the paper tray for printing from now on. The surface of the paper medium to be picked up is imaged. The imaging unit 52 is realized by this imaging unit. The QR code generation unit 53 generates a QR code to be embedded in a paper medium to be printed. The QR code generation unit 53 includes a registration information collection unit 56, an information registration unit 57, and a coding processing unit 58. The registration information collection unit 56 collects information related to paper fingerprints. The information registration unit 57 transmits the information related to the paper fingerprint collected by the registration information collection unit 56 to the DBMS server 5 as the paper fingerprint registration information to be held and managed. The DBMS server 5 receives paper fingerprint identification information (hereinafter, “paper fingerprint ID”) created in response to new registration of paper fingerprint registration information. The encoding processing unit 58 encodes the paper fingerprint ID sent from the DBMS server 5 to generate a QR code. In the present embodiment, a QR code that is a two-dimensional code is adopted as code data to be embedded in a paper medium, and a QR code is generated by encoding a paper fingerprint ID. As described above, the QR code in the present embodiment refers to a QR code generated by encoding a paper fingerprint ID. The synthesizing unit 54 synthesizes the QR code generated by the QR code generating unit 53 with the image data to be printed. The print execution unit 55 executes printing of the image data to which the QR code is added. Thus, a paper medium created by printing image data of an electronic document to be printed on a paper medium is referred to as a “paper document” in the present embodiment.

  On the other hand, the copy function processing unit 60 includes a reading unit 61, a copy processing unit 62, the QR code generation unit 53, the synthesis unit 54, and the print execution unit 55 described above. The reading unit 61 reads a paper document in conjunction with the scanner 34. The copy function processing unit 60 executes printing of image data formed by reading a paper document with the scanner 34 in response to a copy instruction, and the copy processing unit 62 is a main part thereof. The copy processing unit 62 includes a QR code detection unit 63, a collation processing unit 64, and an unreadable processing unit 65. When the paper document to be read is a paper document with a QR code created by the printing function processing unit 50, the QR code detection unit 63 detects the QR code printed on the paper document. The collation processing unit 64 collates the paper fingerprint obtained from the image data acquired by the reading unit 61 with the paper fingerprint obtained from the DBMS server 5 based on the QR code detected by the QR code detection unit 63. The collation processing unit 64 includes a QR code decoding unit 66 and a paper fingerprint acquisition unit 67. The QR code decoding unit 66 decodes the paper fingerprint ID encoded by decoding the QR code. The paper fingerprint acquisition unit 67 acquires paper fingerprint image data corresponding to the paper fingerprint ID from the DBMS server 5 by sending and inquiring about the paper fingerprint ID. The unreadable processing unit 65 performs data processing on the detected QR code detected by the QR code detecting unit 63, thereby making the QR code in a recoverable state and unreadable. This data processing will be described in detail later.

  FIG. 5 is a block configuration diagram of a verification function processing unit that executes the verification function according to the present embodiment. Since the verification function processing unit 70 performs functional processing for verifying the validity of a paper document, the paper document with the QR code described above is the processing target. The verification function processing unit 70 includes a reading unit 71, a verification processing unit 72, and an information output unit 73. The reading unit 71 reads a paper document in conjunction with the scanner 34. The verification processing unit 72 constitutes a main part of the verification function processing unit 70, and the QR code detection unit 74 encodes the paper fingerprint ID from the image data sent from the reading unit 71 and embeds it in the paper document. The detected QR code is detected. A QR code detection unit 74, a collation processing unit 75, a legibility enabling processing unit 76, and an information acquisition unit 77 are included. The collation processing unit 75 collates the paper fingerprint obtained from the image data acquired by the reading unit 71 with the paper fingerprint obtained from the DBMS server 5 based on the QR code detected by the QR code detection unit 74. The collation processing unit 75 includes a QR code decoding unit 78 and a paper fingerprint acquisition unit 79. The QR code decoding unit 78 decodes the paper fingerprint ID encoded by decoding the QR code. The paper fingerprint acquisition unit 79 acquires paper fingerprint image data corresponding to the paper fingerprint ID from the DBMS server 5 by sending and inquiring the paper fingerprint ID. Of the QR codes detected by the QR code detection unit 74, the readable processing unit 76 restores the QR code that has been processed by the unreadable processing unit 65 so as to be readable. The information acquisition unit 77 acquires information related to the paper fingerprint from the DBMS server 5. The information output unit 73 outputs information about the paper fingerprint acquired in the verification process.

  The above-described components 51 to 55, 61, 62, and 71 to 73 are based on a cooperative operation between a computer that constitutes any one of the devices 1 to 4 or a computer that is installed and a program that operates on a CPU mounted on the computer. Realized. Further, the program used in this embodiment can be provided not only by communication means but also by storing it in a recording medium such as a CD-ROM.

  In the description of the operation of the present embodiment to be described below, unless otherwise specified, a case where printing, copying, and verification processes are mainly performed using the multifunction machine 3 is described as an example. 71 is the network scanner 1, the QR code generation unit 53, the copy processing unit 62 and the verification processing unit 72 are the multifunction machine 3 or another computer, the composition unit 54, the print execution unit 55 and the information output unit 73 are the network printer 2 It can be executed by combining a plurality of devices such as using them.

  Next, the operation in this embodiment will be described. First, a process for creating a new paper document used in the present embodiment will be described with reference to the flowchart shown in FIG.

  When the user of the client PC 4 performs a predetermined print instruction operation, the document data to be printed is transmitted to the network printer 2 or multifunction device 3 designated as the print instruction destination. Here, assuming that the multifunction device 3 is designated, the print request receiving unit 51 in the multifunction device 3 receives the image data of the document to be printed sent from the client PC 4 (step 110). Then, the following printing process is executed (step 120). This printing process will be described with reference to the flowchart shown in FIG.

  The paper medium on which the document data is to be printed is discharged from the paper tray to the conveyance path inside the multifunction machine 3, and the imaging unit 52 images the surface of the paper medium (step 121). When the imaging data sent from the imaging unit 52 is received, the registration information collection unit 56 in the QR code generation unit 53 extracts the fiber pattern of the paper medium, that is, the paper fingerprint, from the imaging data, and further print date information, print request The identification information of the print requesting user and / or client PC 4 that can be specified from the information, the printing apparatus, in this case the identification information of the multifunction machine 3, etc. are collected as information related to the paper fingerprint (step 122). Then, the information registration unit 57 transmits the information related to the paper fingerprint collected by the registration information collection unit 56 to the DBMS server 5 as the paper fingerprint registration information for registration (step 123). Since the paper fingerprint ID is returned from the DBMS server 5 in response to the new registration of the paper fingerprint registration information, the QR code generating unit 53 obtains the paper fingerprint ID (step 124), and encodes the QR code. Generate (step 125). The paper fingerprint is a fiber pattern of the paper medium as described above, and the transparency of the paper changes randomly due to the randomness of the entanglement of the fibrous material constituting the paper. By reading the transmitted light or reflected light of the paper, the characteristics having randomness distributed along the surface of the paper are captured as image data. As a scanner for capturing image data, for example, a scanner having a resolution of 400 dpi can be used. A preset area (for example, 32 × 32 bits) in the paper is read in an 8-bit gray scale gradation. FIG. 15 shows an example of the read paper fingerprint image data.

  Upon receiving the generated QR code, the synthesizing unit 54 generates image data to be actually printed by synthesizing the QR code with the image data of the document received by the print request receiving unit 51 (step 126). Then, the print execution unit 55 prints and outputs the image data with the QR code added to the paper medium from which the paper fingerprint has been acquired (step 127). As a rule, the print position on the paper medium uses the margin part that exists at the top right of the paper medium. However, if there is no margin part, the back side of the paper or a part of the image data so that the QR code can be recognized. It is also possible to print in a superimposed manner.

  In this embodiment, printing is executed in this way. As described above, a QR code of a paper fingerprint ID for identifying a paper fingerprint of the paper medium is embedded in a predetermined position in the paper document.

  Next, processing when a paper document printed by the above printing processing is copied using the multifunction device 3 will be described with reference to the flowchart shown in FIG.

  When the user sets a paper document on the platen of the scanner 34 and performs a predetermined copy instruction operation, the reading unit 61 reads the paper document. Thereby, when the image data of the paper document is acquired (step 131), the QR code detection unit 63 in the copy processing unit 62 detects the QR code from the image data (step 132). As a method for detecting the QR code, the method described in pages 65 and 66 of the JIS standard "two-dimensional code symbol-QR code-basic specification (JIS X 0510)" is used.

  Here, when the QR code is not detected from the image data read normally, the paper document to be copied is not created by the printing process described above, and the history management target It can be considered that it is not. Therefore, in such a case (N in step 133), in order to make the paper document to be copied under the management in the present embodiment in the future, the paper document created by copying is processed as described above. (Step 141). That is, the QR code of the paper fingerprint ID of the paper medium is embedded in the paper document to be copied.

  If a QR code representing a paper fingerprint ID is detected from the image data (Y in step 133), collation is performed according to the following procedure. That is, first, the QR code decoding unit 66 performs a decoding process on the detected QR code (step 134). If decoding fails (N in step 135), the user is notified that decoding of the QR code has failed (step 142), and the process ends as an error. The notification method is performed by a desired method such as display on the operation panel 33. If the QR code has been successfully decoded (Y in step 135), the paper fingerprint acquisition unit 67 transmits the paper fingerprint ID obtained by the decoding as key information to the DBMS server 5 and is identified by the paper fingerprint ID. Image data is acquired (step 136). On the other hand, the collation processing unit 64 extracts the fiber pattern data, that is, the image data of the paper fingerprint from the predetermined position of the image data obtained by the reading process by the reading unit 61 (step 137). The collation processing unit 64 collates the image data of each paper fingerprint obtained in this way (step 138). Note that, for example, the method described in Patent Document 1 can be used as the verification method. Specifically, paper fingerprint image data identified by the following fingerprint ID is used as reference data, and the read paper fingerprint image data is used as first collation data. Further, the image data of the paper fingerprint read by slightly shifting the position and slightly rotating the direction with respect to the time when the first verification data is acquired is used as the second verification data, and the image data of the paper fingerprint read from a different paper is the first. As the collation data 3, the correlation value between the reference data and each collation data is calculated. Next, a normalized score of the maximum correlation value is calculated as a feature representing the distribution degree of the correlation value for each of the first to third collation data. Normalized score = (maximum correlation value−average correlation value) / (standard deviation of correlation values). If the paper fingerprint is correct, the normalized score of the first matching data is very high, the normalized score of the third matching data is very low, and the normalized score of the second matching data is between Value. Therefore, it is possible to determine whether or not the paper fingerprints match by appropriately setting the threshold value of the normalized score and comparing the value of the normalized score obtained by the calculation with the threshold value. Here, if the collation fails (N in step 139), the read paper document has been copied by a copier not compatible with the document management system in the present embodiment, or only QR code is obtained by another means. Can be determined to be a paper document created by taking illegal measures such as copying it to another paper document, so the user is notified that the read paper document may have been generated by unauthorized means (Step 143), the process ends as an error. If the paper fingerprint collation is successful (Y in step 139), the unreadable processing unit 65 subsequently crushes the QR code included in the image data read by the reading unit 61 in a recoverable state. (Step 140). When this process is performed, the QR code can be detected but temporarily cannot be read. Details of this processing will be described later. Thereafter, a copy of the paper document is created by performing the above-described printing process (step 141). In the printing process, as described above, a paper fingerprint ID is assigned by the DBMS server 5 to identify a paper fingerprint of a paper medium to be printed, and a QR code created by encoding the paper fingerprint ID is used as an image of the document. Embedded in the data.

  Here, in the printing process performed when the QR code is not detected in the above-described QR code detection process (step 132), the QR code is newly embedded in the paper document. That is, there is only one QR code that can be read in a paper document created by copying. On the other hand, when a QR code is detected in the QR code detection process, one or more QR codes are detected. Here, when only one QR code is detected in the paper document to be copied, the paper document created by copying has one existing QR code made unreadable in step 140 and a new one in step 141. There will be one legible QR code embedded in the. In the printing process, since the QR code is printed at a predetermined position, the two QR codes are basically printed in a state of being aligned on the paper surface. Further, when two QR codes are detected in the paper document to be copied, two existing QR codes that have been made unreadable in step 140 are newly embedded in step 141 in the paper document created by copying. There will be one readable QR code. The same applies when three or more QR codes are detected in the paper document to be copied. That is, when n QR codes (n is a natural number) are detected in the paper document to be copied, the QR document that has been made unreadable in step 140, and the 141 in the paper document created by copying, In FIG. 1, one readable QR code newly embedded is present side by side. As a result, although (n + 1) QR codes exist on the paper surface, there is always one effective QR code.

  In the present embodiment, as described above, the QR code that is not useful due to copying is left in an unreadable state without being deleted from the paper, so that the paper document is created by being copied several times. You can check it at a glance. Since the QR codes that have been crushed in this way are arranged on the paper, it is obvious from the user that the history of this paper document is properly managed, and psychological deterrence against fraudulent acts by the user. It becomes possible to give an effect.

  Next, the verification process of the paper document created as described above will be described with reference to the flowchart shown in FIG.

  When the user sets a paper document on the platen of the scanner 34 and performs a predetermined verification instruction operation, the reading unit 61 reads the paper document. Thereby, when the image data of the paper document is acquired (step 151), the QR code detection unit 74 in the verification processing unit 72 detects the QR code from the image data (step 152). There is a possibility that a plurality of QR codes are printed on the paper document, but all QR codes are detected by this processing. Here, when the QR code is not detected from the image data read normally, the paper document to be copied is not created by the printing process described above, and the history management target It can be considered that it is not. Therefore, in such a case (N in step 153), it is determined that the read paper document is a paper document that is not a verification target in the present embodiment, and the user is informed that the QR code detection has failed. Notification is made (step 161), and the verification process is terminated as an error. The notification method may be limited to the display on the operation panel 33, but in the present embodiment, the user is notified of information related to the paper fingerprint to be verified as a result of the verification process. You may make it notify a detection error. The same applies to other error processing described later in the verification processing.

  When a QR code representing a paper fingerprint ID is detected from the image data (Y in step 153), one of the detected QR codes is selected and the following processing is repeatedly executed. That is, first, the QR code decoding unit 78 performs a decoding process on the QR code selected as the processing target (step 154). Here, if the decoding is successful (Y in step 155), and if the QR code is successfully decoded more than once (Y in step 156), the paper document to be verified can be decoded. Therefore, the user is notified of the QR code duplication error (step 166), and the verification process is terminated as an error. In the verification process according to the present embodiment, the number of successful QR codes is counted. However, if the QR code is successfully decoded for the second time or more despite the successful decoding of the QR code. The reason for the error is as follows.

  In other words, it has been described that the QR code printed on a paper document in the copy process is made unreadable by crushing other than the paper fingerprint ID of the paper medium (step 140 in FIG. 8). Therefore, the QR code that can be normally decoded by the QR code decoding process should be only one QR code generated by encoding the paper fingerprint ID of the paper medium, and there may not be two or more. Therefore, the case where the decoding can be normally performed twice or more in the QR code decoding process is not normal.

  On the other hand, if the QR code decryption process is successful for the first time (N in step 156), the paper fingerprint acquisition unit 79 transmits the paper fingerprint ID obtained by the decryption to the DBMS server 5 as key information, and Image data of a paper fingerprint identified by the paper fingerprint ID is acquired (step 157). On the other hand, the collation processing unit 75 extracts fiber pattern data, that is, paper fingerprint image data, from a predetermined position of the image data obtained by the reading process by the reading unit 71 (step 158). The collation processing unit 75 collates the image data of each paper fingerprint obtained in this way (step 159). Note that, for example, the method described in Patent Document 1 can be used as the verification method. Here, if the paper fingerprint collation fails (N in step 160), there is a possibility that the paper document is fraudulent. Therefore, as collation error processing, for example, from the DBMS server 5 using the paper fingerprint ID as a key, The paper fingerprint registration information of the paper document is acquired and presented to the user (step 167). Then, the process ends as an error. On the other hand, if the paper fingerprint collation is successful (Y in step 160), a verification result indicating that the collation is successful for the QR code to be processed is obtained, so that the processing for the QR code is completed and the next unverified If the QR code remains, the processing target is shifted to the QR code (N in step 161). Even if a result of verification success is obtained in this process, if the QR code to be processed later is successfully decoded for the second time or more, the verification process is finally ended as an error. (Step 166).

  Subsequently, the QR code decoding unit 78 performs a decoding process on the QR code newly selected as the processing target (step 154). The case of successful decryption in this decryption process is as described above. However, if the decryption process succeeds, the success of the decryption process corresponds to the second time, so the verification of the paper document ends with a result of failure. To do.

  When decryption fails (N in Step 155), the legibility enabling processing unit 76 performs restoration processing on the QR code to be processed (Step 162). In other words, the fact that decoding has failed despite the detection of the QR code can be determined that the QR code corresponds to a QR code that has been unreadable by the unreadable processing unit 65. Therefore, the legibility enabling processing unit 76 restores the QR code to a legible state by performing a restoration process that cancels the data processing performed by the illegible processing part 65. In order to perform the restoration process for canceling the data processing performed by the illegible processing unit 65, the readable processing unit 76 must recognize the contents of the data processing. In the present embodiment, the information used for the data processing is acquired from the processing information management server 6. QR code crushing processing by the unreadable processing unit 65 and restoration processing by the readable processing unit 76 will be described later. In this restoration process, the QR code is returned to a readable state, that is, to a decodable state, but the decoding process is also performed. That is, in the restoration process, the decoding process is performed after the restoration process.

  If the restoration process in step 162 is successful (Y in step 163), the paper fingerprint ID can be acquired from the QR code. Therefore, the information acquisition unit 77 sends the paper fingerprint ID and makes an inquiry, thereby inquiring the DBMS server 5 The paper fingerprint registration information corresponding to the paper fingerprint ID is acquired from (step 164).

  In this way, if the processing for the QR code selected as the processing target is completed and the next unverified QR code remains, the processing target is shifted to that QR code (N in step 161).

  On the other hand, if the restoration process has failed (N in step 163), the user is notified that the QR code restoration has failed (step 165), and the process ends as an error.

  As described above, when the verification process is performed on all the QR codes embedded in the paper document, the information output unit 73 displays the verification result data on the operation panel 33 or the operation panel 33 when the verification process is requested. Send to the destination specified for input. The output destination includes, for example, the printer engine 36, the network printer 2, or the client PC 4. The verification result data is printed at each output destination, displayed on the display 18, or stored in the HDD 14.

  Here, the QR code crushing process in step 140 in FIG. 8 and the QR code restoring process in step 162 in FIG. 9 will be described in detail. In the present embodiment, four unreadable processing is exemplified.

  FIG. 10 is a diagram for explaining the first non-readable / readable process. In order to make the QR code 80 temporarily unrecoverable, image data of a mask pattern 81 generated in black and white binary is prepared in advance, and mask composition is performed on the image data of the QR code 80 by exclusive OR. . At this time, the mask pattern 81 is set in the maskable range 84 so as not to overlap with the position detection pattern 83 of the QR code 80 as shown in FIG. When such image data of the mask pattern 81 is subjected to exclusive OR synthesis with the image data of the QR code 80, the QR code image subjected to mask synthesis can be detected because the position detection pattern 83 remains as it is. However, since the code portion of the QR code 82 is masked, it cannot be decoded. The unreadable processing unit 65 performs the above processing as data processing.

  When the same mask image is synthesized by exclusive OR with the image data of the QR code 82 synthesized with the mask, the image data of the original QR code 80 can be obtained. At this time, it is necessary to completely match the position of the image data of the QR code 82 and the image data of the mask pattern 81 which are combined with the mask. In this alignment, the position information of the position detection pattern 83 is used. It is feasible. The legibility enabling processing unit 76 performs the above processing as restoration processing.

  Information relating to the image data of the mask pattern 81 (hereinafter simply referred to as “mask image”) is handled as confidential information and is held and managed by the processing information management server 6. The illegible processing unit 65 and the readable processing unit 76 must use the same mask pattern 81, but each acquires a mask image from the processing information management server 6 when performing the processing. . Note that the mask pattern 81 is prepared for a plurality of mask patterns 81, for example, changed for each model of the device that performs the illegibility / enabling process, or changed for each copy number or used department. And you may make it use properly. In this case, it is necessary to manage information by associating a QR code with a mask pattern.

  FIG. 12 is a diagram for explaining the second non-readable / readable process. In this processing, the white area of the QR code 80 is filled with a color other than white or black. In order to restore the painted QR code 85 to a decodable state, the original QR code 80 is obtained by performing limited color, which is a general image processing technique, and acquiring only white and black images. Image data can be obtained. The color to be painted is preferably a dark color that is determined to be black when converted to grayscale and binarized. In the case of a light color, when it is converted to gray scale and binarized, the color information disappears and a QR code image can be obtained normally.

  FIG. 12 shows an example in which the position detection pattern is also filled. Originally, it is necessary to fill only the maskable range 84 in FIG. 11, and this should be done. However, in the case of color filling, if the limited color is applied to the entire paper document image data before the QR code detection process in step 152 of FIG. 9 is performed, the QR code can be detected. The case where is filled is illustrated.

  FIG. 13 is a diagram for explaining the third non-readable / readable process. In this process, dots of a drawing unit smaller than the drawing unit of QR code 80 (small square constituting the QR code) are added. That is, the image data 86 including dots is synthesized. In order to restore the QR code 87 to which the dots are added, image data of the original QR code 80 can be obtained by performing isolated point removal processing, which is general image processing. That is, the legibility enabling processing unit 76 performs isolated point removal processing as restoration processing. Even if the isolated point removal process is performed, a small drawing unit may remain in the black and white edge portion or the like. In other words, some unevenness may be formed on the straight line. However, there is no problem because the decoding process of the QR code 80 does not have a large influence that causes an error.

  In FIG. 13 as well, as in FIG. 12, in principle, dots may not be added to the position detection pattern portion. However, before the QR code detection process is performed, the entire paper document image data is isolated. If the point removal process is performed, the QR code can be detected.

  FIG. 14 is a diagram for explaining a fourth de-readable / readable process. In this process, the QR code 80 is mirror-inverted. Since the QR code 80 can be detected if there are three position detection patterns, it can be detected as a QR code even if it is mirror-inverted. However, the QR code 88 that has been mirror-inverted is inverted in content from the original QR code 80. Therefore, decoding is impossible.

  Information for holding image data such as a mask image used for the above-described illegibility / enabling processing and designating a method of mirror image reversal is stored and managed in the processing information management server 6, Regardless of the device, paper documents can be created and verified. Of course, if a device for creating and verifying a paper document is specified and only a single mask image or the like is used, each device holds a mask image or the like without using the processing information management server 6. You may comprise as follows.

  According to the present embodiment, when a new paper document is created by copying a paper document, the QR code of the paper fingerprint ID added to the copy source paper document is processed to be unreadable without being deleted. When verifying a newly copied paper document, the unreadable QR code is restored to a readable QR code, so that the document can be accessed without accessing the history management server. History, specifically, a paper fingerprint ID can be obtained from a paper document at hand. Of course, data not included in the QR code can also be obtained from the DBMS server 5.

  In addition, since a plurality of crushed QR codes are arranged in a paper document, it is possible to appeal to a user that the history management is thorough, and has a psychological deterrent effect against unauthorized use. be able to.

  Further, even if a plurality of QR codes are arranged on a paper document, QR codes that are not directly related to the paper document are crushed, so that it is easy to specify a paper fingerprint ID to be collated.

  In this embodiment, a paper fingerprint ID is encoded to create a QR code. However, as information relating to paper fingerprints, paper fingerprint image data itself is encoded to generate a QR code. The information may be QR-coded. In the present embodiment, the QR code that is generally used is described as an example of the data code added to the printing paper. However, a code other than the QR code may be used.

1 is a block configuration diagram showing an embodiment of a document management system according to the present invention. FIG. It is a hardware block diagram of the computer contained in the document management system in this Embodiment. FIG. 2 is a hardware configuration diagram of a multifunction machine according to the present embodiment. FIG. 3 is a block configuration diagram of a print function processing unit that executes a print function and a copy function processing unit that executes a copy function in the present embodiment. It is a block block diagram of the verification function process part which performs the verification function in this Embodiment. It is the flowchart which showed the process when a paper document is newly produced in this Embodiment. 5 is a flowchart showing a printing process in the present embodiment. It is the flowchart which showed the copy process in this Embodiment. It is the flowchart which showed the verification process of the paper document in this Embodiment. It is a figure for demonstrating the 1st non-readable / readable process in this Embodiment. It is the figure which showed the structure of QR Code used in this Embodiment. It is a figure for demonstrating the 2nd de-readable / readable process in this Embodiment. It is a figure for demonstrating the 3rd non-readable / readable process in this Embodiment. It is a figure for demonstrating the 4th non-readable / readable process in this Embodiment. It is a figure which shows the image data of a paper fingerprint.

Explanation of symbols

  1 Network scanner, 2 Network printer, 3 MFP, 4 Client PC, 5 DBMS server, 6 Processing information management server, 7 Network, 11, 31 CPU, 12, 39 ROM, 13, 38 RAM, 14, 35 Hard disk drive ( HDD), 15 HDD controller, 16 mouse, 17 keyboard, 18 display, 19 I / O controller, 20 network controller, 21 internal bus, 32 address data bus, 33 operation panel, 34 scanner, 36 printer engine, 37 network interface (I) / F), 40 external media interface (I / F), 50 printing function processing unit, 51 print request receiving unit, 52 imaging unit, 53 QR code generating unit, 54 combining unit, 55 printing 56, registration information collection unit, 57 information registration unit, 58 encoding processing unit, 60 copy function processing unit, 61, 71 reading unit, 62 copy processing unit, 63, 74 QR code detection unit, 64, 75 verification processing unit , 65 Unreadable processing unit, 66 QR code decoding unit, 67, 79 Paper fingerprint acquisition unit, 70 Verification function processing unit, 72 Verification processing unit, 73 Information output unit, 76 Readability processing unit, 77 Information acquisition unit, 78 QR code decoding unit.

Claims (11)

First reading means for reading a first paper document;
Imaging means for imaging a paper surface of a second paper document created by printing image data of the first paper document read by the first reading means;
Generation processing means for generating code data by encoding specific information of a paper fingerprint obtained from imaging data of the paper surface imaged by the imaging means;
First detection means for detecting code data of paper fingerprint identification information printed on the first paper document by analyzing the image data of the read first paper document;
An unreadable processing means for performing data processing on the code data detected by the first detecting means in an unreadable state in a recoverable state;
The second paper document is printed by adding the code data generated by the generating means to the image data of the first paper document including the code data processed indecipherably by the unreadable processing means. Printing means to create,
Second reading means for reading a second paper document created by the printing means;
Second detection means for detecting code data of paper fingerprint identification information printed on the second paper document by analyzing the image data of the read second paper document;
Readable processing means for restoring the readable code data of the code data detected by the second detecting means to be readable;
Output means for outputting information relating to the paper fingerprint based on the paper fingerprint identification information obtained from the legible code data;
A document management system comprising: The document management system according to claim 1,
Storage means for storing paper fingerprint registration information;
Registration means for registering information related to a paper fingerprint obtained from imaging data of the paper surface imaged by the imaging means in the storage means as paper fingerprint registration information;
Obtaining means for obtaining the paper fingerprint registration information from the storage means based on the paper fingerprint identification information obtained from the code data made readable;
Have
The document management system, wherein the output means outputs information acquired by the acquisition means. The document management system according to claim 1,
Document management characterized in that it has means for holding the image data used in common for the data processing by the illegible processing means and the restoration processing by the readable processing means, or for specifying a method to be used in common system. Imaging means for imaging a paper surface of a second paper document created by printing image data of the first paper document;
Generation processing means for generating code data by encoding specific information of a paper fingerprint obtained from imaging data of the paper surface imaged by the imaging means;
First detection means for detecting code data of the paper fingerprint identification information printed on the first paper document by analyzing the image data of the read first paper document;
An unreadable processing means for performing data processing on the code data detected by the first detecting means in an unreadable state in a recoverable state;
The second paper document is printed by adding the code data generated by the generating means to the image data of the first paper document including the code data processed indecipherably by the unreadable processing means. Printing means to create,
A printing apparatus comprising: The printing apparatus according to claim 4.
The printing apparatus, wherein the unreadable processing means performs a data processing process for synthesizing mask image data with code data. The printing apparatus according to claim 4.
The printing apparatus according to claim 1, wherein the unreadable processing means performs a data processing process in which the code data is painted with a color other than the color constituting the code data. The printing apparatus according to claim 4.
The printing apparatus according to claim 1, wherein the unreadable processing unit performs a data processing process of adding dots of a drawing unit smaller than a drawing unit of the code data to the code data. The printing apparatus according to claim 4.
The printing apparatus, wherein the unreadable processing means performs a data processing process for reversing the code data in a mirror image. Reading means for reading a paper document printed using the printing apparatus according to claim 4;
Detecting means for detecting code data of paper fingerprint identification information printed on the paper document by analyzing image data of the read paper document;
Readability processing means for restoring the code data that has been unreadable to the code data detected by the detection means so as to be legible,
Output means for outputting information relating to the paper fingerprint based on the paper fingerprint identification information obtained from the legible code data;
A document management apparatus comprising: On the computer,
Imaging the paper surface of the second paper document created by printing the image data of the first paper document;
Encode the specific information of the paper fingerprint obtained from the captured image data of the paper surface to generate code data,
By analyzing the image data of the read first paper document, code data of the paper fingerprint identification information printed on the first paper document is detected,
The detected code data is processed in an unreadable manner in a recoverable state,
A second paper document is created by adding the generated code data to the image data of the first paper document including the code data that has been processed into unreadable data, and printing.
A program characterized by that. On the computer,
A printed paper document is read by executing the program according to claim 10;
By analyzing the image data of the read paper document, the code data of the paper fingerprint identification information printed on the paper document is detected,
Of the detected code data, the code data that has been processed unintelligibly is restored to be readable,
Output paper fingerprint information based on paper fingerprint identification information obtained from legible code data.
A program characterized by that.