JP5162947B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus, an image reading method, and an image reading program, and more particularly to an image reading apparatus, an image reading method, and an image reading program suitable for reading an image in which digital information is embedded.

  Conventionally, a technique for reading an image formed on a document, recognizing characters from the image, and displaying the recognized characters is known. For example, an e-mail transmission / reception system described in Japanese Patent Application Laid-Open No. 11-088633 includes information recognition means for recognizing at least an e-mail address of a transmission destination from a communication information entry area included in a read image, and at least a recognized transmission destination. Address storage means for storing communication information including the e-mail address, and display means for displaying and outputting the stored destination e-mail address.

  However, since the e-mail address must be formed as a human-readable character image on the manuscript, there is a problem that a character image representing the e-mail address is unnecessarily formed on the manuscript.

Japanese Patent Application Laid-Open No. 6-22119 describes a technique for forming a copy-forgery-inhibited pattern image embedded with digital information on a document. According to this technique, since the embedded digital information is formed as an image of an indecipherable tint block pattern, it is possible to prevent the digital information from being known to the person viewing the document. However, when confidential information is included in an original image, there is a problem that when the original image is copied, the image including the confidentiality is copied.
JP-A-11-088633 JP-A-6-22119

  The present invention has been made to solve the above-described problems, and one of the objects of the present invention is to provide an image reading apparatus capable of preventing confidential information from leaking from an image formed on a document. It is to be.

In order to achieve the above-described object, according to an aspect of the present invention, an image reading device reads a document on which a document image including a tint block pattern in which digital information is embedded is read, and outputs a document image. An image forming unit that forms an image on a recording medium, a detecting unit that detects a predetermined pattern from a document image output from the reading unit, and an extracting unit that analyzes the detected predetermined pattern and extracts digital information If the extracted digital information includes authentication information, authentication means for authenticating on the condition that the authentication information is accepted; and if the digital information includes information prohibiting partial copying of the document, A partial image generating unit that generates a partial image excluding a portion where copying of a document is prohibited, and a document image output from the reading unit by the image forming unit are formed. Before, when the digital information extracted contains the authentication information, provided on condition that it is authenticated by the authentication unit, a data control means for controlling to display the display data included in the digital information, the image forming The means forms a document image on a recording medium on the condition that the digital information includes information prohibiting copying of a part of the document and is authenticated by the authentication means, and if the digital information is not authenticated by the authentication means, the partial image the formed on the recording medium.

According to this aspect, a document on which a document image including a tint block pattern in which digital information is embedded is read, and a predetermined pattern is detected from the document image. Then, the detected predetermined pattern is analyzed, and digital information is extracted. When the digital information includes information that prohibits copying of a part of the document, the document image is formed on the recording medium on the condition that it is authenticated, and when it is not authenticated, the partial image is formed on the recording medium . Therefore, if the images formed on the originals contains sensitive information, it is possible to prevent the confidential information is formed on the recording medium. As a result, it is possible to provide an image reading apparatus capable of preventing confidential information from leaking from an image formed on a document. When the digital information includes authentication information, the digital information is displayed on the condition that the authentication information is accepted. For this reason, it is possible to prevent leakage of confidential information when the digital information includes confidential information.

Preferably, the information processing device further includes user identification means for receiving identification information for identifying the user, and the data control means displays from the display data included in the extracted digital information based on the received identification information. Selection means for selecting the part is included.

According to this aspect, identification information for identifying the user is received, and a portion to be displayed is selected from the digital information based on the received identification information. For this reason, the digital information which can be output by a user can be varied.

Preferably, if the digital information contains the information prohibiting the copying of the document, further comprising an image formation prohibition means to prohibit the formation of the original image by the image forming means.

  According to this aspect, when the digital information includes information that prohibits copying of a document, it is prohibited to form a document image on a recording medium. For this reason, it is possible to prevent leakage of confidential information when the document image includes confidential information.

  Preferably, when the reading unit reads a plurality of documents, the extraction unit analyzes a plurality of predetermined patterns detected from the plurality of documents by the detection unit, and extracts digital information.

  According to this aspect, when a plurality of originals are read, a plurality of predetermined patterns respectively detected from the plurality of originals are collectively analyzed, and digital information is extracted. For this reason, digital information can be embedded in a plurality of originals.

  Preferably, the data control unit switches the display of the digital information each time a document image is output when a plurality of documents are read by the reading unit.

  Preferably, the data control unit controls the display of the document image output from the reading unit based on the extracted digital information.

  According to this aspect, since the display of the document image is controlled, when the document image includes confidential information, it is possible to prevent the confidential image from being displayed due to the document image being displayed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  Hereinafter, an MFP (Multi Function Peripheral) will be described as an example of an image reading apparatus. FIG. 1 is a perspective view showing the appearance of the MFP. Referring to FIG. 1, MFP 100 includes an automatic document feeder (ADF) 10, an image reading unit 20, an image forming unit 40, a paper feeding unit 50, and a post-processing unit 60. The MFP 100 also includes an operation panel 9 as a user interface with the user on the upper surface.

  The ADF 10 automatically conveys a plurality of documents set on the document feed tray 11 one by one to a predetermined document reading position set on the platen glass of the image reading unit 20, and the image reading unit 20 The document on which the document image is read is discharged onto the document discharge tray 12. The image reading unit 20 includes a light source that irradiates light to a document conveyed to a document reading position, and a photoelectric conversion element that receives light reflected by the document and collected by a lens, and according to the size of the document. Scan the original image. The photoelectric conversion element converts the received light into a document image, which is an electrical signal, and outputs it to the image processing unit 30. The paper feed unit 50 conveys a storage medium such as paper stored in a paper feed tray to the image forming unit 40.

  The image processing unit 30 performs image processing such as noise removal processing, character enhancement processing, and smoothing processing on the document image. Details of the image processing unit 30 will be described later. The image forming unit 40 forms an image by a known electrophotographic method, and based on the original image input from the image processing unit 30, the image is formed on a recording medium such as a sheet conveyed by the paper feeding unit 50. Form.

  The post-processing unit 60 discharges the recording medium on which the image is formed. The post-processing unit 60 has a plurality of discharge trays, and can sort and discharge the recording media on which images are formed. The post-processing unit 60 includes a punch hole processing unit and a staple processing unit, and can perform punch hole processing or staple processing on the discharged recording medium.

  In the present embodiment, MFP 100 is described as an example of an image reading apparatus. However, instead of MFP 100, for example, a scanner, a printer, a facsimile, a personal computer, or the like may be used.

  FIG. 2 is a block diagram illustrating an example of a circuit configuration of the MFP. Referring to FIG. 2, MFP 100 includes a main circuit 101, a facsimile unit 3, and a communication control unit 5. The main circuit 101 is connected to an automatic document feeder (ADF) 10, an image reading unit 20, an image processing unit 30, an image forming unit 40, a paper feeding unit 50, and a post-processing unit 60.

  The main circuit 101 includes a CPU 111, a RAM 112 used as a work area of the CPU 111, a flash memory 113 for storing programs executed by the CPU 111, a display 114, an operation unit 115, and a mass storage device. A hard disk drive (HDD) 116 and a data communication control unit 117 are included.

  The CPU 111 executes an image reading program stored in the flash memory 113. The CPU 111 is connected to the display 114, the operation unit 115, the HDD 116, and the data communication control unit 117, and controls the entire main circuit 101. CPU 111 is connected to facsimile unit 3, communication control unit 5, ADF 10, image reading unit 20, image forming unit 40, paper feed unit 50, and post-processing unit 60, and controls the entire MFP 100.

  The display 114 is a display device such as a liquid crystal display (LCD) or an organic ELD (Electro Luminescence Display), and displays an instruction menu for the user, information about acquired image data, and the like. The operation unit 115 includes a plurality of keys, and accepts input of various instructions, data such as characters and numbers by user operations corresponding to the keys. The operation unit 115 includes a touch panel provided on the display 114. Display 114 and operation unit 115 constitute operation panel 9 provided on the upper surface of MFP 100.

  The data communication control unit 117 includes a LAN terminal 118 that is an interface for communication using a communication protocol such as TCP (Transmission Control Protocol) or UDP (User Datagram Protocol), and a serial communication interface terminal 119 for serial communication. . The data communication control unit 117 transmits / receives data to / from an external device connected to the LAN terminal 118 or the serial communication interface terminal 119 in accordance with an instruction from the CPU 111.

  When a LAN cable for connecting to a network is connected to the LAN terminal 118, the data communication control unit 117 communicates with another MFP or computer connected via the LAN terminal 118. Furthermore, the data communication control unit 117 communicates with other computers connected to the Internet.

  When a device is connected to the serial communication interface terminal 119, the data communication control unit 117 communicates with a device connected to the serial communication interface terminal 119, for example, a digital camera, a digital video camera, or a portable information terminal. Input and output image data. The serial communication interface terminal 119 can be connected to a memory card 119A incorporating a flash memory. The CPU 111 can update the program by controlling the data communication control unit 117 to read a program to be executed by the CPU 111 from the memory card 119 </ b> A and store it in the flash memory 113.

  A recording medium for storing a program to be executed by the CPU 111 is not limited to the memory card 119A, but a flexible disk, a cassette tape, an optical disk (CD-ROM (Compact Disc-Read Only Memory) / MO (Magnetic Optical Disc)). / MD (Mini Disc) / DVD (Digital Versatile Disc)), IC card (including memory card), optical card, mask ROM, EPROM (Erasable Programmable ROM), EEPROM (Electronically Programmable ROM), and other media such as EEPROM Good. Further, the CPU 111 downloads a program from a computer connected via the data communication control unit 117 and stores it in the flash memory 113 or stores the program in the flash memory 113 so that the computer writes the program in the flash memory 113. The programmed program may be loaded into the RAM 112 and executed by the CPU 111. The program here includes not only a program directly executable by the CPU 111 but also a source program, a compressed program, an encrypted program, and the like.

  The communication control unit 5 is a modem for connecting the CPU 111 to the public switched telephone network (PSTN) 7. A telephone number in PSTN 7 is assigned in advance to MFP 100, and when a call is made from the facsimile apparatus connected to PSTN 7 to the telephone number assigned to MFP 100, communication control unit 5 detects the call. When the communication control unit 5 detects a call, the communication control unit 5 establishes a call and causes the facsimile unit 3 to communicate.

  The facsimile unit 3 is connected to the PSTN 7 and transmits facsimile data to the PSTN 7 or receives facsimile data from the PSTN 7.

  FIG. 3 is a functional block diagram showing detailed functions of the image processing unit 30. Referring to FIG. 3, the image processing unit 30 includes a first scanner image processing unit 51, a second scanner image processing device, a compression / decompression processing unit 71, a printer image processing unit 81, and a tint block detection unit 91. ,including.

  The first scanner image processing unit 51 receives a document image output from the image reading unit 20 line by line. The first scanner image processing unit 51 includes a shading correction unit 53, an interline correction unit 55, and a chromatic aberration correction unit 57.

  The shading correction unit 53 removes uneven illumination of the light source provided in the image reading unit 20 from one line of the original image. The shading correction unit 53 outputs one line of the document image subjected to the shading correction to the interline correction unit 55. The data for one line of the original image includes R (red) data, G (green) data, and B (blue) data. The interline correction unit 55 synchronizes the R data, the G data, and the B data so that each of the R data, the G data, and the B data is on the same line of the document. The chromatic aberration correction unit 57 corrects distortion in the main scanning direction caused by the lens included in the image reading unit 20. The chromatic aberration corrector 57 outputs the corrected document image to the second scanner image processor 61, the tint block detector 91, and the CPU 111. The document image output from the chromatic aberration correction unit 57 includes R, G, and B images.

  The second scanner image processing unit 61 includes a resolution conversion unit 62, a background removal processing unit 63, an area determination unit 65, a color conversion unit 64, a character edge correction unit 66, and an error diffusion unit 67. The resolution conversion unit 62 converts the document image to a resolution designated by the user. The background removal processing unit 63 deletes the color of the background portion of the document image so that the next region determination unit 65 can easily determine the region. The area discriminating unit 65 extracts a character area representing characters and a photograph area representing photographs or figures from the original image. The color conversion unit 64 converts the document image from the RGB color space to the CMY color space. Specifically, R, G, and B images included in the document image are converted into CMY and K (black) images. The character edge correction unit 66 performs processing for emphasizing characters on the character region of the document image. The error diffusion unit 67 performs error diffusion processing on the photographic area of the document image.

  The compression / decompression processing unit 71 receives a document image including CMY and K images from the second scanner image processing unit 61. The compression / decompression processing unit 71 compresses the document image and stores it in the RAM 112. Then, in accordance with an instruction from the CPU 111, the compressed document image stored in the RAM 112 is read and decompressed. Since the original image is not expanded until an image formation instruction is issued from the CPU 111, the original image can be prohibited from being formed on the recording medium during that time. Further, when an instruction for prohibiting the formation of a document image is input from the CPU 111, the compression / decompression processing unit 71 deletes the compressed document image stored in the RAM 112. Thereby, it is possible to inhibit the document image from being formed on the recording medium.

  The printer image processing unit 81 includes an image correction unit 82, an image synthesis unit 83, and a screen processing unit 84. The image correction unit 82 receives a document image from the compression / decompression processing unit 71. Further, the image correction unit 82 receives a mask instruction from the CPU 111. The mask instruction includes information indicating a partial area (mask area) of the document image. When the mask instruction is input, the image correction unit 82 deletes a partial area of the document image. Thereby, it is possible to prohibit the formation of a part of the original image.

  The image composition unit 83 receives a background pattern addition instruction from the CPU 111. The background pattern addition instruction includes a background pattern. The tint block pattern is an image in which digital information is embedded. More specifically, the tint block pattern is an image in which a plurality of tint blocks associated with the digital information are arranged. Digital information is information in which 0 and 1 are arranged. A background pattern is an image in which a plurality of dots having different sizes and densities are arranged according to a predetermined rule. A predetermined number of arrays of 0s and 1s and one of a plurality of tint blocks are associated in advance. When the tint block addition instruction is input from the CPU 111, the image composition unit 83 synthesizes the tint block pattern included in the tint block addition instruction with the original image. As a result, a document image including a tint block pattern is generated.

  The screen processing unit 84 executes screen processing for optimizing the number, shape, angle, etc. of screen lines of the document image. The screen processing unit 84 outputs the processed document image to the image forming unit 40.

  The tint block detection unit 91 includes a resolution conversion processing unit 92, a preprocessing unit 93, a tint block pattern detection unit 94, and a digital information detection unit 95. The resolution conversion processing unit 92 converts the RGB document image input from the first scanner image processing unit to a predetermined resolution. The predetermined resolution may be a predetermined resolution and may be a resolution suitable for detecting a tint block pattern.

  The preprocessing unit 93 executes processing such as removing noise from the document image. Also, processing such as binarization of the document image may be executed in order to detect the tint block pattern. The background pattern detection unit 94 detects a plurality of background patterns from the document image. Specifically, if any of a plurality of predetermined ground patterns is included in the document image, the ground pattern is extracted. Then, a tint block pattern is detected from the arrangement order of the plurality of extracted tint blocks. The tint block pattern detection unit 94 outputs the tint block pattern detected from the document image to the digital information detection unit 95.

  The digital information detection unit 95 detects digital information from the tint block pattern. Since a plurality of background patterns are arranged in the background pattern, digital information is detected by arranging an array of 0 and 1 previously associated with each of the plurality of background patterns according to the array of the background patterns. The digital information detection unit 95 outputs the detected digital information to the CPU 111.

  FIG. 4 is a functional block diagram illustrating an example of functions of the CPU. Referring to FIG. 4, CPU 111 operates digital information receiving unit 121 for receiving digital information from image processing unit 30, information display control unit 123 for controlling digital information to be displayed on the display, and MFP 100. A user authentication unit 129 for authenticating a user, a document image reception unit 135 for receiving a document image from the image processing unit 30, an authentication information reception unit 133, an authentication unit 131, and an image authentication information reception unit 145; An image authentication unit 143, an image display control unit 137 for controlling a document image to be displayed on the display 114, an image formation control unit 151 for controlling an image for image formation by the image forming unit 40, including.

  When digital information is input from the image processing unit 30, the digital information receiving unit 121 receives the digital information, and receives the received digital information as an information display control unit 123, an authentication unit 131, an image authentication unit 143, and an image formation control unit. 151 is output. The digital information receiving unit 121 receives digital information detected from a document image every time the image processing unit 30 processes one document image. The digital information receiving unit 121 determines whether or not the digital information detected from one document image alone constitutes one digital information. When digital information is divided and embedded in a plurality of document images, the digital information receiving unit 121 partially receives the digital information. For this reason, the digital information receiving unit 121 receives a plurality of pieces of digital information embedded in a plurality of document images input from the image processing unit 30 each time a plurality of document images are read. The digital information receiving unit 121 sequentially stores partial digital information received in the RAM 112 every time a document image is read. Then, when the digital information as one unit is accumulated in the RAM 112, the digital information receiving unit 121 reads out the digital information as one unit from the RAM 112, and displays the information display control unit 123, the authentication unit 131, and the image authentication unit 143. And output to the image formation controller 151.

  User authentication unit 129 authenticates a user who operates MFP 100. When the user inputs the user ID and password to the operation unit 115, the user authentication unit 129 receives the user ID and password from the operation unit 115. The flash memory 113 stores in advance a user table including at least one user record including a user ID, a password, and an ID level. The user authentication unit 129 refers to the user table and determines whether or not a user record including the received user ID and password is stored in the flash memory 113. The user authentication unit 129 authenticates if a user record including the received user ID and password is stored in the flash memory 113, and otherwise does not authenticate. If the authentication is successful, the user authentication unit 129 outputs the user ID of the authenticated user to the information display control unit 123.

  The authentication unit 131 receives digital information from the digital information receiving unit 121. When the digital information includes authentication information, the authentication unit 131 displays a message prompting the user to input authentication information on the display 114. When the user inputs authentication information to the operation unit 115, the authentication information reception unit 133 receives the authentication information from the operation unit 115 and outputs the received authentication information to the authentication unit 131. The authentication unit 131 compares the authentication information included in the digital information with the authentication information input from the authentication information receiving unit 133, and outputs a signal indicating successful authentication to the information display control unit 123 if they match.

  When the digital information includes authentication information, the information display control unit 123 displays the digital information on the display 114 when a signal indicating authentication success is input from the authentication unit 131. If no signal is input, the digital information is not displayed on the display 114.

  The information display control unit 123 includes a selection unit 125 and a prohibition information display unit 127. The selection unit 125 receives digital information from the digital information reception unit 121 and a user ID from the user authentication unit 129. Digital information is classified into a plurality of ID levels. The portion of the digital information corresponding to a certain ID level includes a portion corresponding to a lower ID level. For example, when digital information is classified into five levels of ID levels 1 to 5, ID level 1 is the highest level, and ID levels 2, 3, 4, and 5 are lower in order of ID levels. The digital information portion corresponding to level 5 is included in the portions corresponding to other ID levels 1 to 4. When the user authentication unit 129 does not authenticate the user ID and the user authentication unit 129 does not input the user ID, the lowest ID level 5 is set.

  The selection unit 125 refers to a user table stored in advance in the flash memory 113, extracts a user record including a user ID input from the user authentication unit 129, and acquires an ID level included in the user record. The selection unit 125 extracts a portion corresponding to the ID level from the digital information input from the digital information reception unit 121 and displays the portion extracted from the digital information on the display 114. For this reason, the digital information displayed on the display 114 can be made different depending on the ID level previously assigned to the user.

  The prohibition information display unit 127 receives digital information from the digital information reception unit 121. The prohibition information display unit 127 displays a message on the display 114 indicating that the copy of the document is prohibited when the digital information includes information prohibiting the copy of the document.

  The image authentication unit 143 receives digital information from the digital information receiving unit 121. When the digital information includes image authentication information, the image authentication unit 143 displays a message prompting the user to input the image authentication information on the display 114. When the user inputs authentication information to the operation unit 115, the image authentication information reception unit 145 receives the image authentication information from the operation unit 115 and outputs the received image authentication information to the image authentication unit 143. The image authentication unit 143 compares the image authentication information included in the digital information with the image authentication information input from the authentication information receiving unit 133, and if they match, a signal indicating successful authentication is sent to the image display control unit 137 and The image is output to the image formation control unit 151.

  When a document image is input from image reading unit 20, document image receiving unit 135 receives the document image and outputs the received document image to image display control unit 137.

  The image display control unit 137 receives digital information from the digital information reception unit 121 and receives a document image from the document image reception unit 135. When the input digital information includes image authentication information, the image display control unit 137 displays a document image on the display 114 when a signal indicating authentication success is input from the image authentication unit 143. If a signal indicating successful authentication is not input from the unit 143, the document image is not displayed on the display 114. Here, an image displayed on the display by the image display control unit 137 is referred to as a preview image.

  Here, the case where the image authentication information and the authentication information are different is shown as an example, but only one of them may be used. For example, when only the authentication information is used, the image authentication unit 143 displays a document image on the display 114 when the authentication unit 131 receives a signal indicating that the authentication is successful.

  The image display control unit 137 includes a partial image generation unit 139 and a preview image correction unit 141. When the digital information includes information that partially prohibits copying of the document, the partial image generation unit 139 masks a portion where copying of the document image is prohibited and includes a portion where copying is not prohibited Generate an image. The partial image generation unit 139 displays the generated partial image (preview image) on the display 114. When the digital information includes information that partially prohibits copying of the document, the image display control unit 137 is generated by the partial image generation unit 139 before the signal indicating the authentication success is input from the image authentication unit 143. The displayed partial image is displayed on the display 114, and when a signal indicating authentication success is input from the image authentication unit 143, the original image is displayed on the display 114.

  When the digital information includes information for changing the display method of the document image to be displayed, the preview image correction unit 141 corrects the document image (preview image) to be displayed according to the display method. The information for changing the display method is, for example, the display direction, brightness, color, resolution, and size. The image display control unit 137 displays the document image corrected by the preview image correction unit 141 on the display 114.

  The image formation control unit 151 includes an image formation prohibition unit 153, a partial image generation instruction unit 155, and a tint block pattern synthesis instruction unit 157. When the digital information input from the digital information receiving unit 121 includes information prohibiting copying of the document, the image forming prohibiting unit 153 sends an instruction to prohibit the formation of the document image to the compression / decompression process of the image processing unit 30. To the unit 71. As a result, the compression / decompression processing unit 71 deletes the compressed document image stored in the RAM 112, so that the document image is not formed on the recording medium.

  When the digital information includes information that partially prohibits copying of the document, the partial image generation instructing unit 155 sends a mask instruction for masking the portion where copying of the document is prohibited to the image correcting unit of the image processing unit 30. 82. The mask instruction includes mask area information indicating an area to be masked of the document image. As a result, the image correction unit 82 of the image processing unit 30 generates a partial image in which the image of the area specified by the mask area information of the original image is partially deleted. It is not formed on a recording medium.

  The copy-forgery-inhibited pattern combination instructing unit 157 receives the embedded information from the embedded information receiving unit 159. The embedded information receiving unit 159 receives embedded information input to the operation unit 115 by the user. The embedded information includes display data, information for controlling the output of the display data, and information for controlling the output of the document image. The information for controlling the output of the display data includes information for prohibiting display of all or at least a part of the display data, an ID level corresponding to the display data, and authentication information. The information for controlling the output of the original image includes information prohibiting display of the entire original image or at least a part thereof, information for correcting the original image, and prohibiting image formation of the entire original image or at least a part thereof. Information and image authentication information. The information for correcting the document image includes the direction in which the document image is displayed, brightness, color, resolution, and size.

  When the embedded information is input, the tint block pattern synthesis instruction unit 157 converts the embedded information into digital information. Corresponding to the embedded information, a predetermined binary code is determined, and the embedded information is converted into digital information composed of the binary code. Further, the background pattern combination instruction unit 157 generates a background pattern consisting of an array of background patterns based on the digital information, and outputs a background pattern addition instruction including the background pattern to the image composition unit 83 of the image processing unit 30. As a result, the image composition unit 83 synthesizes the copy-forgery-inhibited pattern with the original image, so that the original image including the copy-forgery-inhibited pattern is formed on the recording medium.

  FIG. 5 is a first diagram illustrating an example of a screen displayed on the operation panel 9. FIG. 5 shows a screen displayed when the digital information includes authentication information and information that partially prohibits copying of the document. Referring to FIG. 5, display 114 includes an area for displaying a message, a preview image 301, and an area 311 for inputting a password. In the message display area, the message “A document protected by security has been read. If you want to cancel protection, enter the password.” Is displayed. In the preview image 301, areas 303 and 305 indicated by hatching are masked. When the user inputs a password in the area 311, the protection is released.

  FIG. 6 is a second diagram illustrating an example of a screen displayed on the operation panel 9. FIG. 6 shows a screen that is displayed when a password is entered in the area 311 of the screen shown in FIG. Here, an example in which authentication information and image authentication information are the same is shown. That is, a screen displayed when one password input in the area 311 matches the authentication information and the image authentication information included in the digital information is shown. Referring to FIG. 6, display data 310 included in the digital information is displayed on display 114. Unlike the preview image 301 shown in FIG. 5, the preview image 301A does not include the masked areas 303 and 305 but includes all parts of the document image.

  FIG. 7 is a flowchart illustrating an example of the flow of image reading processing. The image reading process is a process executed by the CPU 111 or the image processing unit 30 when the CPU 111 and the image processing unit 30 execute an image reading program stored in the flash memory 113. Referring to FIG. 7, CPU 111 or image processing unit 30 determines whether or not a document has been read. The process waits until the document is read by the image reading unit 20, and if the document is read by the image reading unit 20, the process proceeds to step S02. When the image reading unit 20 reads a document, the CPU 111 receives a document image from the image reading unit 20 (step S02).

  In the next step S03, it is determined whether or not the document image includes a tint block pattern. If at least one of a plurality of predetermined background patterns is extracted from the document image, it is determined that the background pattern is included. If the original image includes a tint block pattern, the process proceeds to step S04; otherwise, the process proceeds to step S07.

  In step S04, digital information is detected. Specifically, by extracting a tint block pattern from a document image, determining a set of 0 and 1 arrays respectively corresponding to a plurality of tint blocks included in the tint block pattern, and arranging them according to the tint block pattern, the digital information To decide.

  In the next step S05, it is determined whether or not the digital information includes display data. If the digital information includes display data, the process proceeds to step S06; otherwise, the process proceeds to step S07. In step S06, a digital information display process is executed, and the process proceeds to step S07. In step S07, an image output process is executed, and the process proceeds to step S08. The digital information display process and the image output process will be described later.

  In step S08, it is determined whether there is a document to be read next. If the document exists, the process returns to step S01, and if not, the process ends. Judgment is made based on whether or not a document exists in the ADF 10. Accordingly, digital information and a document image are displayed on the display 114 every time one document is read.

  FIG. 8 is a flowchart showing an example of the flow of digital information display processing. The digital information display process is a process executed in step S06 in FIG. Referring to FIG. 8, it is determined whether or not the display data is protected (step S11). It is determined whether the digital information includes authentication information (password). If the digital information includes the authentication information, it is determined that the display data is protected. If the display data is protected, the process proceeds to step S12. If not, the process proceeds to step S14.

  In step S12, the user is requested to input a password. Specifically, a message requesting input of a password is displayed on the display 114. When the user inputs a password to the operation unit 115, the password input from the operation unit 115 is accepted. In step S13, it is determined whether or not the password input by the user matches the authentication information. If the password matches the authentication information, the process proceeds to step S14; otherwise, the process returns to the image reading process. Therefore, the display data included in the digital information is displayed on condition that the same password as the authentication information included in the digital information is input.

  In step S14, it is determined whether display of display data is restricted. Here, it is determined whether or not the digital information is classified by the ID level. If the digital information is classified based on the ID level, the process proceeds to step S15; otherwise, the process proceeds to step S23. In step S23, all of the display data is displayed on the display 114.

  In step S15, it is determined whether the user ID has been input. It is determined whether the user ID authenticated by the user authentication unit 131 is accepted. If the user ID has been input, the process proceeds to step S16; otherwise, the process proceeds to step S21. In step S21, display data for which the ID level is not set is selected from the display data included in the digital information, and the process proceeds to step S22. Display data for which no level is set is display data that is displayed when a user ID is not input.

  In step S16, the process branches depending on the ID level corresponding to the user ID. A user record including a user ID is read from a user table stored in advance in the flash memory 113, and an ID level included in the user record is acquired. If the ID level is level 1, the process proceeds to step S20. If the ID level is level 2, the process proceeds to step S19. If the ID level is level 3, the process proceeds to step S18. If the ID level is level 4, the process is performed. Advances to step S17.

  In step S17, display data set to level 4 or lower is selected from the display data included in the digital information, and the process proceeds to step S22. The display data set to level 4 or lower includes display data set to level 4 and display data set without level setting. In step S18, display data set at level 3 or lower is selected from the display data included in the digital information, and the process proceeds to step S22. In step S19, display data set at level 2 or lower is selected from the display data included in the digital information, and the process proceeds to step S22. In step S20, the display data set to level 1 or lower among the display data included in the digital information, in other words, all of the display data are selected, and the process proceeds to step S22.

  In step S22, the display data selected in any of steps S17 to S21 is displayed on display 114. If the digital information includes authentication information, the digital information is displayed on the display 114 on condition that the authentication information is input. Therefore, when the digital information includes display data including confidential information, the confidential information is Leakage can be prevented. Further, when the digital information includes display data classified at the ID level, only the portion corresponding to the ID level of the display data is displayed on the display 114, so that the display data for each user who operates the MFP 100 is displayed. The display part can be made different.

  FIG. 9 is a flowchart illustrating an example of the flow of image output processing. The image output process is a process executed in step S07 of the image reading process shown in FIG. Referring to FIG. 9, CPU 111 creates a preview image based on the document image (step S31). A reduction process for reducing the document image to a size that can be displayed on the display 114 is performed.

  Then, it is determined whether the document is a copy-prohibited document (step S32). It is determined whether or not the digital information includes information prohibiting copying of the document or information prohibiting copying of a part of the document. If so, the process proceeds to step S33; otherwise, the process proceeds to step S40.

  In step S33, it is determined whether or not copying of the document is partially prohibited. It is determined whether the digital information includes information prohibiting copying of the original or information prohibiting copying of a part of the original. If it includes information prohibiting copying of a part of the document, it is determined that the copy is partially prohibited, and the process proceeds to step S34. If it includes information prohibiting copying of the document, the process proceeds to step S51.

  In step S34, the copy prohibited area is masked. In the preview image created in step S31, an area included in the information prohibiting copying of a part of the document is deleted and masked by replacing it with another image. Then, the preview image is displayed on the display 114 (step S35).

  In the next step S36, the user is requested to input an image password. Specifically, a message requesting input of the image password is displayed on the display 114. When the user inputs an image password to the operation unit 115, the image password input from the operation unit 115 is accepted. In step S37, it is determined whether or not the image password input by the user matches the image authentication information included in the digital information. If the image password matches the image authentication information, the process proceeds to step S38; otherwise, the process proceeds to step S39. In step S38, the mask of the preview image is removed. Specifically, the preview image created in step S31 is displayed on the display 114 instead of the preview image displayed in step S35.

  In step S39, a partial image is generated, and the process proceeds to step S40. Specifically, a mask instruction is output to the image processing unit 30. The mask instruction includes information indicating a partial area (mask area) of the document image included in the digital information. As a result, a partial area of the original image is deleted by the image correcting unit 82, so that the formation of a partial image of the original image can be prohibited.

  In step S40, it is determined whether or not the display method has been changed. It is determined whether the digital information includes information that changes a display method. If the digital information includes information for changing the display method, the process proceeds to step S41; otherwise, the process proceeds to step S42.

  In step S41, the preview image is corrected according to the display method (step S41). For example, the direction, brightness, color, resolution, and size for displaying the preview image are corrected. In step S42, a preview image is displayed on display 114.

  In step S43, the original image is formed, and the process returns to the image reading process. Specifically, an image formation instruction is output to the compression / expansion processing unit 71 of the image processing unit 30. As a result, the original image stored in the RAM 112 is read out by the compression / expansion processing unit 71, decompressed, and output to the printer image processing unit 81, so that the original image is formed on the recording medium by the image forming unit 40. .

  On the other hand, in step S51, as in step S36, the user is requested to input an image password. In step S52, it is determined whether the image password input by the user matches the image authentication information included in the digital information. If the image password matches the image authentication information, the process proceeds to step S40; otherwise, the process proceeds to step S53.

  In step S53, the original image is deleted, and the process returns to the image reading process. Specifically, an instruction to prohibit the formation of the document image is output to the compression / decompression processing unit 71. As a result, the compression / decompression processing unit 71 deletes the compressed document image stored in the RAM 112, and thus it is prohibited to form the document image on the recording medium.

  FIG. 10 is a flowchart showing another flow of the image reading process. This image reading process is a process executed when digital information is embedded in a plurality of document images. Referring to FIG. 10, the difference from the image reading process shown in FIG. 7 is that step S04A is added between steps S04 and S05. The other processes are the same as the processes shown in FIG. 7, and therefore description thereof will not be repeated here.

  If digital information is detected in step S04, it is determined in step S04A whether or not all digital information has been detected. The digital information may include information indicating that it is midway or final. If the last digital information is detected, the process proceeds to step S05. If not, the process returns to step S01. That is, the document is read until the final digital information is detected, and the process proceeds to step S05 after all the digital information is obtained. For this reason, even when the digital information exceeds the upper limit of information that can be embedded in one original, the digital information can be embedded separately in a plurality of originals. Even when digital information is embedded in a plurality of originals, when a plurality of originals are read and all the digital information is obtained, display control for the digital information or display or Print control can be performed.

  In the present embodiment, the case where an image is formed by the image forming unit 40 is shown as an example of the document image output process. However, the output process is not limited to the image forming process but is stored in the flash memory 113 or the like. Including a process of storing in a medium and a process of transmitting to another apparatus.

  In the above-described embodiment, the MFP 100 has been described as an example of an image reading apparatus. However, the invention is understood as an image reading method or an image reading program for causing a computer to execute the processes illustrated in FIGS. 7 to 10. Needless to say, you can.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

<Appendix>
(1) The image according to claim 4, wherein when the extracted digital information includes information prohibiting copying of the original, the display means displays that copying of the original is prohibited. Reader.
(2) When the digital information includes information that prohibits copying of a part of the document, the data control means extracts a partial image from the document image excluding the portion where copying of the document is prohibited. The image reading apparatus according to claim 8, further comprising a partial image generation unit that generates the partial image.

1 is a perspective view showing an appearance of an MFP. 2 is a block diagram illustrating an example of a circuit configuration of an MFP. FIG. It is a functional block diagram which shows the detailed function of an image process part. It is a functional block diagram which shows an example of the function of CPU. It is a 1st figure which shows an example of the screen displayed on an operation panel. It is a 2nd figure which shows an example of the screen displayed on an operation panel. It is a flowchart which shows an example of the flow of an image reading process. It is a flowchart which shows an example of the flow of a digital information display process. It is a flowchart which shows an example of the flow of an image output process. It is a flowchart which shows another flow of an image reading process.

Explanation of symbols

  9 Operation panel, 10 ADF, 20 Image reading unit, 30 Image processing unit, 40 Image forming unit, 50 Paper feed unit, 60 Post processing unit, 51 Scanner image processing unit, 53 Shading correction unit, 55 Interline correction unit, 57 Chromatic aberration correction unit 61 Scanner image processing unit 62 Resolution conversion unit 63 Background removal processing unit 64 Color conversion unit 65 Area discrimination unit 66 Character edge correction unit 67 Error diffusion unit 71 Compression / decompression processing unit 81 Printer image processing unit, 82 image correction unit, 83 image composition unit, 84 screen processing unit, 91 tint block detection unit, 92 resolution conversion processing unit, 93 pre-processing unit, 94 tint block pattern detection unit, 95 digital information detection unit, 100 MFP 101 main circuit, 111 CPU, 112 RAM, 113 flash memory, 114 display 115 Operation unit 116 HDD 117 Data communication control unit 119A Memory card 121 Digital information reception unit 123 Information display control unit 125 Selection unit 127 Prohibition information display unit 129 User authentication unit 131 Authentication unit 133 Authentication information reception unit, 135 Document image reception unit, 137 Image display control unit, 139 Partial image generation unit, 141 Preview image correction unit, 143 Image authentication unit, 145 Image authentication information reception unit, 151 Image formation control unit, 153 Image formation Prohibition unit, 155 partial image generation instruction unit, 157 copy-forgery-inhibited pattern combination instruction unit, 159 embedded information reception unit, 301, 301A preview image, 310 display data.

Claims (6)

Reading means for reading a document on which a document image including a tint block pattern embedded with digital information is formed, and outputting the document image;
Image forming means for forming an image on a recording medium;
Detecting means for detecting a predetermined pattern from a document image output from the reading means;
Extracting means for analyzing the detected predetermined pattern and extracting digital information;
If the extracted digital information includes authentication information, authentication means for authenticating on condition that the authentication information is accepted;
A partial image generating unit configured to generate a partial image excluding the portion where the copy of the document is prohibited from the document image when the digital information includes information prohibiting copying of a part of the document;
If the extracted digital information includes authentication information before the original image output from the reading unit is formed by the image forming unit, the digital information is included on the condition that the digital information is authenticated by the authentication unit. Data control means for controlling to display the display data included , and
The image forming unit forms the document image on a recording medium on the condition that the digital information includes information prohibiting copying of a part of the document and is authenticated by the authentication unit. An image reading apparatus that forms the partial image on a recording medium when the means does not authenticate . A user identification means for receiving identification information for identifying the user;
The image reading unit according to claim 1, wherein the data control unit includes a selection unit that selects a portion to be displayed from display data included in the extracted digital information based on the received identification information. apparatus. 3. The image reading according to claim 1, further comprising an image formation prohibiting unit that prohibits the image forming unit from forming the original image when the digital information includes information prohibiting copying of the original. apparatus.   The extraction means, when a plurality of originals are read by the reading means, collectively analyzes the predetermined patterns respectively detected from the plurality of originals by the detection means, and extracts digital information; The image reading apparatus according to claim 1. Said data control means, when a plurality of sheets of the document is read by said reading means, every time the original image is output, switching the display of the digital information, the read image according to any one of claims 1-4 apparatus. It said data control means, based on the extracted digital information, controls the display of the document image output from the reading means, the image reading apparatus according to any one of claims 1-5.

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