JP2007194962A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device capable of, for example, printing through scrambling process of a portion of print matter using encrypting, so as to prevent information leakage to a third party. <P>SOLUTION: In an encrypted area, in addition to a decryption key necessary for decryption processing, there is composed an area marker having embedded information indicating which direction and how many times the manuscript concerned is to be read. Accordingly, in the event the third party obtains the manuscript, the security can be improved because the procedure for reading the manuscript cannot be read easily. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention forms image data such as image data of a document read by a scanner, image data of each page of document data generated by an application program, and image data transmitted from the outside as an image on a sheet by page unit. The present invention relates to an image forming apparatus that prints or displays an image on a screen of a display device.

  In recent years, digitization of documents has rapidly spread, but in many cases, it is output as a printed matter on paper according to some need. In the state in which an electronic document is registered as electronic information in an electronic file system or the like, information leakage countermeasures such as encryption at the time of registration as electronic information or authentication of individual users at the time of reading are taken. On the other hand, when a document that cannot be leaked to the outside such as confidential information and personal information is handled as printed matter, it is necessary to prevent the contents from being viewed by an external third party. However, as a method for that purpose, the printed matter is stored in a lockable storage, or personally carried to each desk etc. and personally managed, and information that should not be leaked is partially included. In such a case, a physical method such as partially covering the printed matter with a blindfold sheet has been adopted.

Under such circumstances, Patent Document 1 prints a two-dimensional code in which a digital data is converted into a dot pattern and arranged on a two-dimensional surface in a specific area having no information meaning in the printed matter. An invention is disclosed in which a print area of a two-dimensional code is extracted from an image obtained by optically reading a printed matter including the two-dimensional code printed in this manner, and the original digital data is reproduced.
JP 2000-343784 A

  By the way, when the printed matter that should be prevented from leaking to the outside is managed by the physical method as described above, it is inadvertently left while the individual is carrying it, or forgets to lock the storage. Therefore, there is a high possibility that the content easily leaks when the content is transferred to a third party or viewed by a third party. On the other hand, with the technique disclosed in Patent Document 1 described above, it is possible for a third party to easily know the content by optically reading the document, and it is difficult for the third party to know the content. Such confidential information is not considered.

  The present invention has been made in view of the circumstances as described above, and even if a third party views the document information, the contents cannot be read, and a general reading device (scanner) is used. It is an object of the present invention to provide an image forming apparatus that can be encrypted and formed on a sheet so that it cannot be restored only by performing a normal reading process, that is, output as a printed matter and restored to its original state.

  In short, when the present invention is to print a part or all of image data including confidential information to be printed by performing encryption processing (for example, scrambled image), such image data is printed on paper. In this case, a print condition is designated as a combination of the number of times of reading a document that is formed as an image, that is, a printed document by a reading unit such as a scanner, and a reading direction in each reading process, and is output as a printed matter. Only when the reading process of a document as a printed matter is performed according to reading conditions specified in advance, the decoding process can be performed. Accordingly, it is possible to effectively prevent leakage of confidential information from the contents of the printed matter.

  An image forming apparatus according to the present invention includes: a reading unit that reads an image of a document and generates image data in units of pages; and an image forming unit that forms an image of image data on a sheet in units of pages. An area designation accepting unit that accepts designation of an area of an arbitrary size at an arbitrary position in image data for each page to be imaged by the image forming means, and an arbitrary area that the area designation accepting means accepts designation Encryption processing means for encrypting the image data with a predetermined encryption key, and the number of times read by the reading means and each reading time in the encrypted image data for each page including the area encrypted by the encryption processing means A reading condition designating unit for designating a reading condition in combination with the reading direction of the image, and a document on which the image forming unit forms an image of encrypted image data in units of pages on a sheet. Determining means for determining whether or not the reading means has read in accordance with the reading conditions specified by the reading condition specifying means; and determining means for determining that the document has been read by the reading means in accordance with the reading conditions specified by the reading condition specifying means. And a decryption processing means for restoring the image data of the encrypted area included in the page-unit image data generated by the reading means with a decryption key corresponding to the predetermined encryption key. It is characterized by.

  In such an image forming apparatus according to the present invention, when a document that is an image formed on a sheet by the image forming unit, that is, a printed material is read by the reading unit, the number of readings specified in advance and the respective readings are read. If the reading direction of the document at the time of processing does not match the actual number of readings and the reading direction of the document at the time of each reading process, the decoding process is not performed.

  The image forming apparatus according to the present invention further includes a display unit in the image forming apparatus invention described above, and the encrypted image data of the page unit and / or the image data of the encrypted area is restored by the decryption processing unit. The displayed page unit image data is displayed on the display means as an image.

  In such an image forming apparatus according to the present invention, in the above-described image forming apparatus, one or both of the encrypted image data and the original image data restored from the encrypted image data is printed on a sheet. Is displayed on the display means in the same state as the above.

  Furthermore, the image forming apparatus according to the present invention is configured to cause the external image forming apparatus to form an image by transferring the encrypted image data in units of pages to the external image forming apparatus via a communication line. Features.

  In such an image forming apparatus according to the present invention, the image forming apparatus performs printing by forming image data on a sheet by an external image forming apparatus instead of its own image forming means.

  The image forming apparatus according to the present invention communicates, in the image forming apparatus, page-unit encrypted image data and / or page-unit image data in which the encrypted area image data is restored by the decryption processing unit. The image is displayed on the external display device as an image by transferring it to an external display device via a line.

  In such an image forming apparatus according to the present invention, in the image forming apparatus, one or both of the encrypted image data and the original image data restored from the encrypted image data are formed on a sheet. And displayed on an external display device in the same state as when it is printed.

  An image forming apparatus according to the present invention includes an image data generating unit that generates image data in units of pages that can be formed on a sheet by an external image forming apparatus, wherein the image data generating unit includes: An area designation accepting unit that accepts designation of an area of an arbitrary size at an arbitrary position in the generated image data in page units, and image data of an arbitrary area that the area designation accepting unit accepts designation is encrypted with a predetermined encryption An encryption processing means for encrypting with a key, and an external reading device for a document in which encrypted image data in units of pages including an area encrypted by the encryption processing means is image-formed on a sheet by an external image forming apparatus As a condition for restoring the image data in the encrypted area with a decryption key corresponding to the predetermined encryption key, Characterized by comprising a reading condition specifying means for specifying a reading condition which is a combination of the direction reading when reading number and each read that.

  In such an image forming apparatus according to the present invention, when an image is read by an external reading device, the number of readings designated in advance and the reading direction of the document during each reading process are determined based on the actual number of readings and the number of readings. Image data for printing on a sheet a document that is not decrypted unless it matches the reading direction of the document in the reading process is generated.

  The image forming apparatus according to the present invention is characterized in that in the image forming apparatus described above, the image forming apparatus further comprises a display means, and the encrypted image data for each page is displayed on the display means as an image.

  In such an image forming apparatus according to the present invention, in the above-described image forming apparatus, the encrypted image data is displayed on the display unit in the same state as when it is formed on a sheet and printed.

  Further, the image forming apparatus according to the present invention causes the image forming apparatus to display encrypted image data in units of pages to an external display device via a communication line, thereby displaying the image on the external display device. It is characterized by being.

  In such an image forming apparatus according to the present invention, the encrypted image data is displayed on the external display device in the same state as when the encrypted image data is formed on a sheet and printed.

  The image forming apparatus according to the present invention is the image forming apparatus according to any one of the above-described image forming apparatuses, wherein the encryption processing unit encrypts the image data of the area received by the area designation receiving unit with the predetermined encryption key. Further, the read condition specified by the read condition specifying means is included in the encrypted image data.

  In such an image forming apparatus according to the present invention, in each of the image forming apparatuses described above, when the image data of the designated area is encrypted, the reading condition is included in the encrypted image data.

  The image forming apparatus according to the present invention is the image forming apparatus according to any one of the above-described image forming apparatuses, wherein the encryption processing unit encrypts the image data of the area received by the area designation receiving unit with the predetermined encryption key. Further, the decryption key is included in the encrypted image data.

  In such an image forming apparatus according to the present invention, in each of the image forming apparatuses described above, when the image data in the designated area is encrypted with a predetermined encryption key, the decryption key necessary for the decryption is encrypted. Included in the converted image data.

  The image forming apparatus according to the present invention is the image forming apparatus according to any one of the above-described image forming apparatuses, wherein the area designation receiving unit accepts designation of a rectangular area, and the encryption processing unit accepts designation of the area designation accepting unit. When the image data is encrypted, a marker for determining up / down / left / right is added to at least one of the four corners of the rectangular area for which the designation is accepted.

  In such an image forming apparatus according to the present invention, in each of the image forming apparatuses described above, the designated area, in other words, the printed image is printed by the marker added to at least one corner of the designated rectangular area. As a result, the orientation of the entire original is determined, and the inclination of the original during the reading process is also determined.

  According to the image forming apparatus according to the present invention as described above, a scrambled image or the like is arbitrarily encrypted on a printed document such as text and drawings which are confidential information that is inconvenient to the eyes of a third party. Therefore, even if the printed document is taken away, misplaced or stolen, information leakage can be prevented. Further, when such an original is restored to the original state, the reading process is not performed in accordance with the combination of the number of times of reading of the original specified when encrypted and the reading direction in each reading process. As long as it cannot be restored. Therefore, an encrypted image cannot be restored to its original state unless it is a person who knows the combination of the number of times of reading of the document specified when encrypted and the reading direction in each reading process. So security is improved.

  According to the image forming apparatus according to the present invention as described above, in the above image forming apparatus, one or both of the encrypted image data and the original image data restored from the encrypted image data are stored. Since it is displayed on the display unit in the same state as when formed on a sheet and printed, it is possible to check the encrypted state and the restored state without actually printing.

  According to the image forming apparatus of the present invention as described above, in the above image forming apparatus, printing is performed by forming image data on a sheet by an external image forming apparatus instead of its own image forming means. As in the case of the image data for printing, printing can be performed by a general external image forming apparatus.

  According to the image forming apparatus according to the present invention as described above, in the above image forming apparatus, one or both of the encrypted image data and the original image data restored from the encrypted image data are stored. Since it is displayed on an external display device in the same state as when it is printed on paper, it is actually printed in the encrypted state and the restored state as with normal image data for printing. Without confirmation, it is possible to confirm with a general external display device.

  According to the image forming apparatus according to the present invention as described above, when reading with an external reading device, the number of readings designated in advance and the reading direction of the document during each reading process are the actual number of readings. Since image data to be formed on a sheet for printing a document that is not subjected to decoding processing unless it matches the reading direction of the document at the time of each reading process is generated, a reading device such as a scanner and a printer The same security as that of the above-described image forming apparatus can be given to each page of document data generated by an apparatus such as a personal computer to which an image forming apparatus such as the above is connected.

  According to the image forming apparatus according to the present invention as described above, in the above image forming apparatus, the encrypted image data is displayed on the display unit in the same state as when formed and printed on a sheet. It is possible to check the encrypted state without actually printing it.

  According to the image forming apparatus according to the present invention as described above, in the above image forming apparatus, since the encrypted image data is displayed on the external display device in the same state as when printed, normal printing is performed. As in the case of the image data, the encrypted state can be confirmed on a general external display device without actually printing.

  According to the image forming apparatus according to the present invention as described above, in each of the image forming apparatuses described above, since the reading condition is included in the encrypted image data when the image data of the designated area is encrypted, It is possible to restore even a device other than the encrypted device.

  According to the image forming apparatus according to the present invention as described above, in each of the above image forming apparatuses, when the image data in the designated area is encrypted with a predetermined encryption key, the decryption key is encrypted image data. Therefore, it is possible to restore even an apparatus other than the apparatus that encrypted the image data.

  According to the image forming apparatus according to the present invention as described above, in each of the above image forming apparatuses, the designated area, in other words, the marker added to at least one corner of the designated rectangular area. This makes it possible to determine the orientation of the entire printed document and the state of the document's tilt during the reading process, making it easy to convert the document's orientation to the correct orientation and correct the tilt. Improves.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 are block diagrams showing an embodiment of a configuration example of an image forming apparatus according to the present invention. FIG. 1 shows a multifunction machine 2 including a printer, a scanner, etc., and FIG. 2 shows a personal computer (PC) 3 not including a printer, a scanner, etc., as an embodiment of an image forming apparatus according to the present invention. Yes. The multifunction device 2 and the PC 3 are connected by a network NE.

  The multi-function device 2 includes a control unit 200 using a CPU or MPU, an input unit 210, an output unit 220, a communication unit 230, a storage unit 240, and the like connected to the control unit 200. The control unit 200 controls the operation of itself and the above-described hardware units. The control unit 200 controls itself and the entire MFP 2 according to a control program stored (installed) in advance in the storage unit 240, thereby executing a processing procedure shown in a flowchart described below.

  The input unit 210 includes an operation unit 211 such as a touch panel and a reading unit 212 such as an optical scanner device. Accordingly, the operation unit 211 of the input unit 210 accepts input of operation instructions, selection, range specification, and the like by the user with a pointing device such as a touch panel and / or a mouse. The reading unit 212 of the input unit 210 has an unencrypted document (hereinafter referred to as a non-encrypted document) and a part of the whole or the whole encrypted by optical scanning (reading) by an optical scanner or the like. An image of an original (hereinafter referred to as an encrypted original) is optically read, and digital image data is acquired in units of pages.

  The output unit 220 includes, for example, a display unit 221 such as a liquid crystal display and a printing unit 222 which is an electrophotographic printer, for example. The output unit 220 displays image data in units of pages output from the control unit 200 of the multifunction device 2 on the display unit 221 as a one-page document image, or on the paper by the printing unit 222 which is an image forming unit. By forming and printing it as a one-page printed matter (original), it is output as a soft copy and a hard copy. More specifically, the display unit 221 is configured by a display device using a liquid crystal panel or the like. As will be described in detail later, a preview image of a one-page document (printed material) is displayed and at each time point. Various soft key buttons corresponding to the processing state are displayed. In the present embodiment, the operation unit 211 is configured as a touch panel superimposed on the display unit 221, so that the user presses the portion of the operation unit 211 corresponding to the soft key button displayed on the display unit 221. It is set as the structure operated by.

  The printing unit 222 outputs the image data in a hard copy by printing the encrypted document and the non-encrypted document on appropriate paper based on the page-unit image data.

  The communication unit 230 includes a PC 3 connected via a network NE as a communication line, and an external PC, a printer (printer), a scanner (reading device) not shown in FIGS. 1 and 2. The image data of the original (printed material) is transmitted / received by communicating with the user. As the network NE, a LAN, the Internet, a normal telephone line or the like can be used, and a network in which these are connected to each other may be used.

  The storage unit 240 includes various storage media such as a volatile RAM and a hard disk device that is a rewritable nonvolatile storage device. The hard disk device 241 is used for storing a control program for the control unit 200, for example. The volatile RAM temporarily stores data necessary for processing by the control unit 200 or data generated during the processing as the temporary storage unit 242.

  Although details will be described later in the temporary storage unit 242, an image data storage unit 251, a “suspend” flag 252, a “return” flag 253, and a “frame movement mode” flag for temporarily storing image data to be processed. Storage areas such as a designated paper direction storage unit 255, a designated reading number storage unit 256, a reading paper direction storage unit 257, and a count value storage unit 258 are set, and a working area 259 is also set. The designated reading number storage unit 256 stores a value of the number of readings designated by the user when the encrypted document is decrypted (designated number of readings: the number of times the same encrypted document is read repeatedly). In addition, the designated sheet direction storage unit 255 stores information (designated sheet direction information) related to the reading direction of the encrypted document in order of the number of readings corresponding to the specified number of readings stored in the specified number of readings storage unit 256. The reading sheet direction storage unit 257 sequentially stores information on the reading direction (reading direction information) at the time of each reading process when the encrypted document is actually read a plurality of times. The count value storage unit 258 stores a count value when the count process is necessary for various processes by the control unit 200, and stores an initial value of the count value corresponding to each process.

  The control unit 200 includes software function blocks such as an encryption processing unit 201, a marker recognition unit 202, a decryption processing unit 203, and an image processing unit 204 in addition to functions for controlling itself and the entire MFP 2. . Each of these software functional blocks is a function realized by the control unit 200 executing a control program installed in advance in the hard disk device 241 of the storage unit 240.

  The encryption processing unit 201 encrypts image data in a designated area (encryption designation area) in the page-unit image data read by the reading unit 212 using a conventionally known encryption method. As a result, the encryption designation area is converted into an area (encryption area) replaced with, for example, a scrambled image or the like that cannot be read by human eyes. Although details will be described later, as the encryption designation area, a part of the page-unit image data of the non-encrypted document to be processed can be designated, a plurality of parts can be designated, or the entire page can be designated. It is also possible to specify.

  The marker recognizing unit 202 recognizes image data of an area marker, which will be described later, from image data in page units acquired by the reading unit 212 reading an image of a document. Specifically, the marker recognizing unit 202 recognizes the image data of the area marker included in the page unit image data and specifies the position on the page unit image data. Based on the position of the area marker specified in this way, the size of the encryption area in which the encryption designation area is encrypted and the position of the entire image data are specified by the image processing unit 204. The marker recognizing unit 202 also reads various information embedded in the recognized area marker, for example, as will be described in detail later, but reading conditions of the encrypted document necessary for the decryption processing (number of readings: designated number of readings, paper (Direction: designated paper direction information) and a decryption key are recognized and acquired as data.

  The decryption processing unit 203 uses the decryption key acquired by the marker recognizing unit 202 to decrypt the image data in the encryption area in the image data of the encrypted document, and restores the original image data.

  The image processing unit 204 performs general image processing. Specifically, the inclination of the encryption area based on the position of the area marker specified by the marker recognition unit 202, in other words, the inclination of the entire image data of the encrypted document (when the document is read by the reading unit 212). (Tilt) correction processing, rotation processing of the entire image data of the encrypted document, etc., to bring the relationship between the upper, lower, left and right (direction when the document is read by the reading unit 212) into a normal state.

  Further, in the encryption process, the image processing unit 204 performs processing of extracting image data in page units in order to provide the encryption processing unit 201 with the image data in the area designated as the encryption designated area and perform encryption processing. Process of pasting the image data into the original encryption specification area (the encryption specification area becomes the encryption area by pasting the encrypted image data), generating the image data of the area marker Then, processing for synthesizing the encrypted image data in the encryption area is performed. The area marker decrypts the image data of the encrypted document, such as the designated reading count value and the designated paper direction information, and the decryption key for restoring the encrypted image data in the encryption area. Various information necessary for this is embedded.

  Further, during the decryption process, the image processing unit 204 causes the decryption processing unit 203 to decrypt the encrypted image data in the encryption area specified by the position of the area marker recognized by the marker recognition unit 202. Processing to cut out image data in units, processing to generate unencrypted page-unit image data (unencrypted image data) by pasting the decrypted image data into the original encryption area, etc. Do.

  The PC 3 includes a control unit 300, an input unit 310, a communication unit 330, an output unit 320, a storage unit 340, and the like, which is basically the same as that of the multifunction device 2. However, the PC 3 is greatly different from the multifunction device 2 in that the components corresponding to the reading unit 212, the marker recognition unit 202, the decoding processing unit 203, and the printing unit 222 provided in the multifunction device 2 are not provided. On the other hand, a page data generation unit 305 that is not provided in the multifunction device 2 is provided. In addition, according to such a difference from the multifunction device 2, the temporary storage unit 342 of the PC 3 has an image data storage unit 251 other than the reading sheet direction storage unit 257 of the position storage unit 242 of the multifunction device 2, “ “Interrupt” flag 252, “return” flag 253, “frame movement mode” flag 254, designated sheet direction storage unit 255, designated reading count storage unit 256, count value storage unit 258 and image data storage unit corresponding to the working area 259. 351, “interrupt” flag 352, “return” flag 353, “frame movement mode” flag 354, designated sheet direction storage unit 355, designated reading number storage unit 356, count value storage unit 358, and working area 359 are set. .

  A page data generation unit 305 generates image data in units of pages constituting document data generated by various application programs installed in the PC 3. The page-by-page image data generated by the page data generation unit 305 is encrypted by the encryption processing unit 301 and the image processing unit 304 basically in the same manner as in the above-described multifunction device 2.

  Further, the PC 3 transmits the image data in units of pages encrypted as described above from the communication unit 330 to the multifunction device 2 via the network NE, thereby displaying the image data on the display unit 221 of the multifunction device 2 as an image, In addition, the printing unit 222 can perform printing. Further, the PC 3 transmits the image data in units of pages encrypted as described above from the communication unit 330 to an external terminal device such as another PC via the network NE, whereby the image is displayed on the display unit of the terminal device. Or can be printed on that printing device by sending it to another printing device. Furthermore, the PC 3 can also encrypt the page-unit image data received from the network NE via the communication unit 330 by the encryption processing unit 301 and the image processing unit 304 in the same manner as in the case of the multifunction machine 2 described above. Is possible.

  FIG. 3 is a schematic diagram showing the flow of image data and printed matter when the image forming apparatus according to the present invention is used. In addition to the multifunction machine 2 and the PC 3 which are the image forming apparatuses according to the present invention described above, personal An external general terminal device 1 such as a computer and an external general printer 4 are connected via a network NE. Hereinafter, the flow of image data and printed matter when the image forming apparatus according to the present invention is used will be briefly described with reference to FIG.

  As is apparent from the configuration shown in FIG. 1, the multi-function device 2 has a scanner function (including a copy function), an encryption processing function, a decryption processing function, a printing function, a display function, and a network function. On the other hand, as is apparent from the configuration shown in FIG. 2, the PC 3 does not have a scanner function, a decryption processing function, and a printing function. However, the PC 3 has an encryption processing function and a network function. Further, the general terminal device 1 has a network function, and also has a display function when a display device is connected. In addition, the general terminal device 1 may request encryption processing by transmitting image data in units of individual pages constituting document data generated by an application program to the MFP 2 or the PC 3 using a network function. In addition, printing can be requested by transmitting to the multifunction device 2 or the general printer 4. Further, the general printer 4 can print the non-encrypted document 5 and the encrypted document 6 by receiving image data in units of pages from the multifunction device 2 or the PC 3 using the network function. More specific description will be given below.

  The multifunction device 2 can read both the unencrypted document 5 and the encrypted document 6 by the scanner function. Further, the multifunction device 2 prints both the unencrypted document 5 and the encrypted document 6 read by the scanner function by the printing function, and the unencrypted document in which the encrypted document 6 is restored to the original state by itself. 5 can also be printed. Further, the MFP 2 receives the encrypted image data 7 from the PC 3 by the network function and prints it as the encrypted document 6 by the printing function, or the encrypted document 6 is restored to the original state or originally encrypted. Unencrypted image data 8 that has not been sent can also be transmitted to the PC 3 or the general terminal device 1.

  The general printer 4 can print the encrypted document 6 by receiving the encrypted image data 7 from the PC 3. Also, the general terminal device 1 can receive the non-encrypted image data 8 with the encrypted area restored from the multifunction device 2 and display it on the screen of the display device. Although not shown in FIG. 3, the general printer 4 may print the encrypted document 6 by receiving the encrypted image data 7 in which the designated area is encrypted from the multifunction device 2. It is also possible to receive the unencrypted image data 8 from the machine 2, the PC 3, and the general terminal device 1 and print the unencrypted document 5.

  Next, an outline of image processing by the image forming apparatus of the present invention will be described with reference to the schematic diagrams of FIGS. 4 (a) to 4 (c). FIG. 4A is a schematic diagram showing the unencrypted document 5 and FIG. 4B is a schematic diagram showing the encrypted document 6 in which the encryption designation areas 16 and 17 of the unencrypted document 5 are encrypted. As shown in FIG. 4A, two areas of the non-encrypted document 5, a rectangular area near the upper end and a rectangular area near the lower end, are designated as encryption designation areas 16 and 17. As a result, the encrypted document 6 including the encrypted areas 14 and 15 scrambled, for example, as shown in FIG. 4B is generated. The encryption designation areas 16 and 17 are rectangular areas in the present embodiment, and therefore the encryption areas 14 and 15 are also rectangular areas. Then, area markers 11, 12, and 13 as shown in FIG. 4 (c) are formed at the corners of the encrypted areas 14 and 15, respectively.

  The area marker 11 is in the upper left corner of the encrypted area 14 (15), the area marker 12 is in the upper right corner of the encrypted area 14 (15), and the area marker 13 is in the lower left corner of the encrypted area 14 (15). Each is formed. Therefore, since no area marker is formed at the lower right corner of the encrypted area 14 (15), if the positions of these three area markers 11, 12, 13 on the page-by-page image data are known, The position and size of the encrypted area 14 (15) on the page-by-page image data, the inclination of the page-by-page image data itself, the vertical / horizontal relationship (image orientation), and the like can be easily determined.

  FIG. 5 is a flowchart showing a processing procedure of a main routine (encryption processing main routine) for creating the encrypted document 6 in which the designated area of the non-encrypted document 5 is encrypted. Although this encryption process can be executed by either the multifunction device 2 or the PC 3, the processing in the multifunction device 2 will be mainly described below. When the encryption process is executed by the multifunction device 2, the control unit 200 is installed in the storage unit 340 when the control unit 200 is executed by the PC 3 according to the control program installed in the storage unit 240. Each is processed according to the control program.

  When the MFP 2 performs encryption processing, the control unit 200 causes the reading unit 212 to optically read an image of the non-encrypted document 5 placed on a document table (not shown) of the reading unit 212, and to perform digital processing. Obtained as image data and stored in the image data storage unit 251 (step S11). When encryption processing is performed in the PC 3, image data of a specified page of document data created by various application programs or received from another terminal device 1 or the like is stored in the image data storage unit 351. . Also, when the MFP 2 performs encryption processing, the image data of a specified page of document data received from another terminal device 1 or the like and stored in the image data storage unit 251 may be targeted. Of course it is possible.

  The procedure of the encryption process described below is basically the same in both the multifunction device 2 and the PC 3, and therefore only the case in the multifunction device 2 will be described. First, the user operates the operation unit 211 to set the frame of the encryption designation area 27 for the user to designate the area to be encrypted in the page unit image data stored in the image data storage unit 251 as described above. As shown in FIG. 4, an encryption area designation process for designating in units of rectangles is executed (step S12). This process is executed by the control unit 200 as a flowchart of a subroutine for the encryption area designation process shown in FIGS.

  Hereinafter, the encryption area designation process will be described with reference to the flowcharts of FIGS. 6, 7, and 8. First, the control unit 200 initializes the temporary storage unit 242 for encryption area designation processing (step S31). Specifically, the control unit 200 sets both the “suspend” flag 252 and the “frame movement mode” flag 254 to “off (0)”. The “interrupt” flag 252 is a flag for determining whether to continue the encryption process by being set to “on” when the process being executed at that time is canceled. . The “interrupt” flag 252 is also used in a reading count designation process and a paper direction designation process described later. Further, the control unit 200 clears the working area 259 (a state in which nothing is stored) and also clears the designated sheet direction storage unit 255. Further, the control unit 200 sets “2” as the initial value of the designated reading number value in the designated reading number storage unit 256. The above is the process in step S31. However, although “2” is set as the initial value of the designated number of readings here, the value is not limited to this value, and an optimum value can be set in system design.

  Next, the control unit 200 displays the encryption area designation screen 21 on the display unit 221 (step S32). 9 (a) to 9 (c) are schematic diagrams showing transition of the display state of the encryption area designation screen 21, and FIG. 9 (a) is an initial screen displayed in the processing in the first step S32. is there. As shown in the initial screen shown in FIG. 9A, the image data to be processed stored in the image data storage unit 251 is stored in an almost half area on the left side of the encryption area designation screen 21. A preview screen 26 for displaying as an image in page units is set, and a frame indicating the range of the encryption designation area 27 is displayed.

  Also, in the almost half of the area on the right side of the encryption area designation screen 21, “frame movement mode” buttons 101, “up” are used as buttons for operating the frame of the encryption designation area 27. An “index” button 102U, a “lower index” button 102D, a “left index” button 102L, a “right index” button 102R, an “add” button 104 and a “cancel” button for instructing the procedure of the encryption area designation process itself 105 and “Next” button 106 are displayed. As shown in FIG. 9B, the right side portion of the encryption area designation screen 21 is an “upper-side index” button 103UU, which is used when the frame size of the encryption designation area 27 is changed. Upper Lower Indicator button 103UD, Lower Upper Indicator button 103DU, Lower Lower Indicator button 103DD, Left Left Indicator button 103LL, Left Left Right Indicator button 103LR, Right Left Indicator button 103RL, Right Right Right The “index” button 103RR and the “add” button 104, the “cancel” button 105, and the “next” button 106 for instructing the procedure of the encryption area specifying process itself are displayed. . The display state shown in FIG. 9A and the display state shown in FIG. 9B are switched in accordance with the operation of the “frame movement mode” button 101 as will be described later.

  The control unit 200 displays the processing target image data stored in the image data storage unit 251 as an image in units of pages on the preview screen 26 when displaying the encryption area designation screen 21. The frame of the encryption designation area 27 for designating the area where the user wants to perform encryption is displayed on the image with a broken line (step S33). This broken line is displayed in agreement with the entire outline of the preview screen 26 in the initial state. However, as will be described later, the encryption designation area 27 can be arbitrarily enlarged / reduced and moved, and therefore may be at an appropriate position as long as it is easy for the user to visually confirm.

  FIG. 10 is a schematic diagram showing a coordinate system for displaying the frame of the encryption designation area 27 on the screen of the display unit 221. As shown in FIG. 10, the four vertexes of the frame of the encryption designation area 27 (LT: upper left, RT: upper right, LB: lower left, with coordinate values on the XY coordinate system set on the screen of the display unit 221. RB: lower right). Therefore, the frame of the encryption designation area 27 can be moved and enlarged / reduced by changing the coordinate values of these four vertices (LT, RT, LB, RB). In the following description, the limit processing for the upper limit value and the lower limit value of the coordinate value when the encryption designation area 27 is moved and enlarged / reduced is well-known, and thus the description thereof is omitted.

  In FIG. 9 (a) to FIG. 9 (c), the “frame movement mode” button displayed with “black circle (●)” or “white circle (◯)” in the center of the right side portion of the encryption area designation screen 21 101 indicates whether the “frame movement” mode for moving the entire frame of the encryption designation area 27 is set, or enlargement / reduction of the encryption designation area 27 by moving only one side of the frame. This is a button for indicating whether the “frame enlargement / reduction” mode is set, and for switching the mode. 6, 7, and 8, when the “frame movement” mode is set, the “frame movement mode” flag 254 is turned on (1), and the “frame enlargement / reduction” mode is set. In this case, the “frame movement mode” flag 254 is shown as being off (0). Such ON / OFF of the “frame movement mode” is linked to the “frame movement mode” button 101 and is stored as a setting state of the “frame movement mode” flag 254.

  Next, the control unit 200 determines whether or not the “frame movement” mode is “on” (or off) at that time, that is, the setting state of the “frame movement mode” flag 254 (step S34). . When the “frame movement mode” flag 254 is “ON”, that is, the display state of the “frame movement mode” button 101 is a black circle (●) (YES in step S34), the encryption area designation screen 21 is displayed as shown in FIG. The encryption designation area 27 shown in FIG. Therefore, in this case, the control unit 200 determines whether any of the “upper index” button 102U, the “lower index” button 102D, the “left index” button 102L, and the “right index” button 102R is pressed. (Steps S35, S36, S37, S38).

  If the “upper index” button 102U is pressed (YES in step S35), the control unit 200 determines that an instruction to move up the encryption designation area 27 has been given. In this case, the control unit 200 decreases the Y coordinates of the four vertices (LT, RT, LB, RB) of the frame of the encryption designation area 27 by 1 point, respectively, so that the entire frame of the encryption designation area 27 is displayed on the preview screen 26. A coordinate value for moving upward within the box is calculated (step S39). When the “down index” button 102D is pressed (YES in step S36), the control unit 200 determines that an instruction to move down the encryption designation area 27 has been given. In this case, the control unit 200 increases the Y coordinate of each of the four vertices (LT, RT, LB, RB) of the frame of the encryption designation area 27 by 1 point, so that the entire frame of the encryption designation area 27 is displayed on the preview screen 26. A coordinate value for moving downward within the frame is calculated (step S40).

  Further, when the “left index” button 102L is pressed (YES in step S37), the control unit 200 determines that an instruction to move the encryption designation area 27 to the left is instructed. In this case, the control unit 200 decreases the X coordinates of the four vertices (LT, RT, LB, RB) of the frame of the encryption designation area 27 by 1 point, respectively, so that the entire frame of the encryption designation area 27 is displayed on the preview screen 26. The coordinate value for moving to the left is calculated (step S41). When the “right index” button 102R is pressed (YES in step S38), the control unit 200 determines that an instruction to move the encryption designation area 27 to the right is instructed. In this case, the control unit 200 increases the X coordinate of each of the four vertices (LT, RT, LB, RB) of the frame of the encryption designation area 27 by 1 point, so that the entire frame of the encryption designation area 27 is displayed on the preview screen 26. The coordinate value for moving to the right is calculated (step S42).

  After calculating the X coordinate value and the Y coordinate value of the frame of the encryption designation area 27 as described above, the control unit 200 returns the processing to step S33, thereby moving the frame of the encryption designation area 27 after moving to the preview screen 26. Is displayed again (step S33).

  When none of the “upper index” button 102U, the “lower index” button 102D, the “left index” button 102L, and the “right index” button 102R is operated (NO in any of steps S35, S36, S37, and S38) The control unit 200 determines whether any of the “add” button 104, the “next” button 106, the “cancel” button 105, or the “frame movement mode” button 101 has been pressed (steps S43, S44, S45). , S46).

  When the “add” button 104 is pressed (YES in step S43), the control unit 200 assumes that the frame designated on the preview screen 26 at that time is confirmed as the frame of the encryption designation area 27, and the X The coordinate and Y coordinate values are stored in the working area 259 of the temporary storage unit 242 (step S47). Then, the control unit 200 displays the determined encryption designation area 27 as a designated encryption designation area 28 by, for example, displaying in gray as shown in FIG. 9C (step S48). As a result, the designated encryption designation area 28 can be easily distinguished from the frame of the encryption designation area 27 to be designated next. Thereafter, the control unit 200 returns the process to step S32, whereby the frame of the next encryption designation area 27 is displayed in gray on the preview screen 26 as shown in FIG. 9C. Display in other areas.

  If the “next” button 106 is pressed (YES in step S44), the user wants to end the designation of the encryption designation area and proceed to the next process. The X coordinate and Y coordinate values of the frame of the encryption designation area 27 are stored in the working area 259 of the temporary storage unit 242 (step S49), the encryption area designation process is terminated, and the process returns to the main routine of the encryption process. When the “cancel” button 105 is pressed (YES in step S45), since the user re-specifies the encryption designation area, the control unit 200 sets the “suspend” flag 252 to “on” ( Step S50), the encryption area designating process is terminated, and the process returns to the main routine of the encryption process.

  When the “frame movement mode” button 101 is pressed (YES in step S46), the user stops the operation of moving the frame of the encryption designation area 27 and performs enlargement / reduction (or vice versa). Then, the control unit 200 reversely sets the “frame movement mode” flag 254, that is, switches from “on” to “off” or from “off” to “on” (step S51). Thereafter, the control unit 200 returns the process to step S33. Therefore, in this case, if it is determined in step S34 that the “frame movement mode” flag is “off”, that is, the “frame movement mode” button 101 is displayed with a white circle (◯) (NO in step S34), The encryption area designation screen 21 is in a display state in which the encryption designation area 27 shown in FIG. Therefore, in this case, the control unit 200 controls the “upper upper index” button 103UU, the “upper lower index” button 103UD, the “lower upper index” button 103DU, the “lower lower index” button 103DD, and the “left left index” button 103LL. , “Left side right index” button 103LR, “Right side left index” button 103RL, and “Right side right index” button 103RR are judged (steps S52, S53, S54, S55, S56, S57, S58, S59).

  When the “upper upper index” button 103UU is pressed (YES in step S52), the control unit 200 determines that an instruction has been given to enlarge the encryption designation area 27 by moving the upper side of the frame upward. In this case, the control unit 200 moves the upper side of the encryption designation area 27 upward by enlarging the upper side of the encryption designation area 27 by decreasing the Y coordinates of the upper vertices LT and RT of the upper side of the frame of the encryption designation area 27 by one point. The coordinate value for making it calculate is calculated (step S60).

  When the “upper side lower index” button 103UD is pressed (YES in step S53), the control unit 200 determines that an instruction to reduce the encryption designation area 27 by moving the upper side of the frame downward is given. In this case, the control unit 200 increases the Y coordinates of both the vertices LT and RT on the upper side of the frame of the encryption designation area 27 by 1 point, thereby moving the upper side of the encryption designation area 27 downward and reducing the upper side. The coordinate value for making it calculate is calculated (step S61).

  When the “lower upper index” button 103DU is pressed (YES in step S54), the control unit 200 determines that an instruction has been given to reduce the encryption designation area 27 by moving the lower side of the frame upward. In this case, the control unit 200 moves the lower side of the encryption designation area 27 upward by reducing the Y coordinate of both vertices LB and RB below the frame of the encryption designation area 27 by 1 point. The coordinate value for reducing is reduced (step S62).

  When the “lower side lower index” button 103DD is pressed (YES in step S55), the control unit 200 determines that an instruction is given to enlarge the encryption designation area 27 by moving the lower side of the frame downward. In this case, the control unit 200 moves the lower side of the encryption designation area 27 downward by increasing the Y coordinates of both vertices LB and RB on the lower side of the frame of the encryption designation area 27 by 1 point. The coordinate value for enlarging to (S63) is calculated.

  If the “left side left index” button 103LL is pressed (YES in step S56), the control unit 200 determines that the encryption designation area 27 has been instructed to be enlarged by moving the left side of the frame to the left. . In this case, the control unit 200 moves the left side of the encryption designation area 27 leftward and expands it to the left side by reducing the X coordinates of both vertices LT and LB on the left side of the frame of the encryption designation area 27 by one point. The coordinate value for making it calculate is calculated (step S64).

  When the “left side / right index” button 103LR is pressed (YES in step S57), the control unit 200 determines that the encryption designation area 27 has been instructed to be reduced by moving the left side of the frame to the right. In this case, the control unit 200 increases the X coordinates of both vertices LT and LB on the left side of the frame of the encryption designation area 27 by 1 point, thereby moving the left side of the encryption designation area 27 in the right direction and reducing the left side. The coordinate value for making it calculate is calculated (step S65).

  When the “right side left index” button 103RL is pressed (YES in step S58), the control unit 200 determines that the encryption designation area 27 has been instructed to be reduced by moving the right side of the frame to the left. . In this case, the control unit 200 reduces the right side of the encryption designation area 27 leftward by reducing the X coordinates of both vertices RT and RB on the right side of the frame of the encryption designation area 27 by 1 point, and reduces the right side. The coordinate value for making it calculate is calculated (step S66).

  If the “right side right index” button 103RR is pressed (YES in step S59), the control unit 200 determines that an instruction to enlarge the encryption designation area 27 by moving the right side of the frame to the right is instructed. . In this case, the control unit 200 increases the X coordinates of both vertices RT and RB on the right side of the frame of the encryption designation area 27 by 1 point, thereby moving the right side of the encryption designation area 27 to the right and expanding the right side. The coordinate value for making it calculate is calculated (step S67).

  After the calculation of the X coordinate value and the Y coordinate value of the frame of the encryption designation area 27 as described above, the control unit 200 returns the process to step S33, whereby the encryption designation area 27 after enlargement / reduction is displayed on the preview screen 26. The frame is again displayed (step S33).

  “Upper upper index” button 103UU, “Upper lower index” button 103UD, “Lower upper index” button 103DU, “Lower lower index” button 103DD, “Left side left index” button 103LL, “Left side right index” button 103LR, “Right side” When neither the “left index” button 103RL nor the “right-side right index” button 103RR is pressed (NO in steps S52, S53, S54, S55, S56, S57, S58, and S59), the control unit 200 displays “ It is determined whether any of the “add” button 104, the “next” button 106, the “cancel” button 105, or the “frame movement mode” button 101 has been pressed (steps S43, S44, S45, S46).

  Even when the “frame movement mode” flag 254 is “off”, has any of the “frame movement mode” button 101, the “add” button 104, the “cancel” button 105, or the “next” button 106 been pressed? The determination of whether or not and the processing corresponding thereto are the same as those in the case where the “frame movement mode” flag 254 is “ON”, and the description thereof will be omitted. In any case, when the “next” button 106 or the “cancel” button 105 is pressed (YES in step S44 or S45), the control unit 200 ends the encryption area specifying process and performs the main routine of the encryption process. Return processing to.

  When returning from the encryption area specifying process subroutine as described above to the encryption process main routine of FIG. 5, the control unit 200 confirms the setting of the “suspend” flag 252 (step S13). When the “interrupt” flag 252 is “ON”, that is, when the user interrupts the encryption process (YES in step S13), the control unit 200 clears the working area 259 of the temporary storage unit 242, and designates the specified number of reading times. “2” is set as the designated reading count value in the storage unit 256, the stored content of the designated sheet direction storage unit 255 is cleared (step S22), and the encryption process is terminated. If the “interrupt” flag 252 is “off” (NO in step S13), the control unit 200 designates how many times the encrypted original 6 needs to be read at the time of the decryption process (read count) (Designation process) is performed (step S14). This reading number designation process is shown as a subroutine in the flowchart of FIG.

  Hereinafter, the reading number designation process will be described with reference to the flowchart of FIG. First, the control unit 200 sets the “interrupt” flag 252 and the “return” flag 253 to “off”, respectively (steps S71 and S72). Note that the “return” flag 253 interrupts the process (in this case, the number of readings designation process) that the control unit 200 is currently executing, and returns to the previous process (in this case, the encryption area designation process). This flag is set to “ON” when returning. The “return” flag 253 is also used in a paper direction designation process described later.

  Next, the control unit 200 sets the designated reading number value stored in the designated reading number storage unit 256 in the count value storage unit 258 (step S73). Here, the reason why the designated reading number value stored in the designated reading number storage unit 256 is set in the count value storage unit 258 is that the encryption process is performed with the “Return” button from the paper direction designation process (step S17) described later. This is because, when returning to the main routine, correction is made from the designated reading count value set previously.

  Next, the control unit 200 displays the reading number designation screen 22 as shown in the schematic diagram of FIG. 12 on the display unit 221 (step S74). The reading number designation screen 22 includes a designated reading number display section 29 indicating the number of readings designated at that time, an “upper index” button 107U, a “lower index” button 107D, a “cancel” button 105, and “next”. "Button 106 and" return "button 108 are displayed. When such a reading count designation screen 22 is displayed, the control unit 200 determines whether one of the “upper index” button 107U and the “lower index” button 107D is pressed (steps S75 and S76). .

  When the “upper index” button 107U is pressed (YES in step S75), the control unit 200 increments the count value stored in the count value storage unit 258 by “1” (step S77). When the “lower index” button 107D is pressed (YES in step S76), the control unit 200 decrements the count value stored in the count value storage unit 258 by “1” (step S78). In either case, the control unit 200 returns the process to step S75, and the count value increased or decreased as described above is displayed on the reading count designation screen 22. The limit processing for the upper limit value and the lower limit value of the count value stored in the count value storage unit 258 is well known and will not be described in the description.

  Incidentally, in this case, “2” is set as the initial value of the designated reading number value in the designated reading number storage unit 256. Therefore, when the reading number designation screen 22 is first displayed, the designated reading number display unit 29 is displayed. “2” is displayed in the box. However, the user can arbitrarily increase or decrease the designated reading count value from the initial value “2” by the operation as described above.

  When the “next” button 106 is pressed (both NO in steps S75 and S76, YES in step S79), the control unit 200 counts the count value storage unit 258 because the user has finished specifying the number of readings. However, the count value stored at that time is stored in the designated reading number storage unit 256 as the designated reading number value (step S80), the reading number designation process is terminated, and the process returns to the main routine of the encryption process. As a result, the designated reading number storage unit 256 stores a designated value (designated reading number value) of the number of readings when the document to be processed at that time is decrypted as the encrypted document 6.

  When the “cancel” button 105 is pressed (NO in step S79, YES in S81), the control unit 200 sets the “interrupt” flag 252 to “on” (step S82), and ends the number-of-reads designation process. Return to the main routine of the encryption process. When the “return” button 108 is pressed (NO in step S81, YES in S83), the control unit 200 sets the “return” flag 253 to “on” (step S84), and ends the number of readings designation process. Return to the main routine of the encryption process.

  When the reading number designation process is completed as described above, the control unit 200 returns the process to the main routine of the encryption process shown in FIG. When returning from the reading number specifying process to the main routine of the encryption process, the control unit 200 first confirms the setting of the “interrupt” flag 252 (step S15).

  When the setting of the “suspend” flag 252 is “on”, that is, when the user interrupts the encryption process (YES in step S15), the control unit 200 clears the working area 259 of the temporary storage unit 242 and designates it. “2” is set as the designated reading number value in the reading number storage unit 256, the stored content of the designated sheet direction storage unit 255 is cleared (step S22), and the encryption process is terminated. On the other hand, when the setting of the “interrupt” flag 252 is “off” (NO in step S15), the control unit 200 confirms the setting of the “return” flag 253 (step S16). When the setting of the “return” flag 253 is “on”, that is, when the user interrupts the reading count designation process and restarts the previous encryption area designation process (YES in step S16), the control unit 200 performs the step The processing is returned to S12, and the processing procedure after the above-described encryption area designation processing is executed again. On the other hand, when the setting of the “return” flag 253 is “off” (NO in step S16), the control unit 200 executes the next paper direction designation process (step S17). This paper direction designation process is shown as a subroutine in the flowchart of FIG.

  Hereinafter, the paper direction designation process will be described with reference to the flowchart of FIG. First, the control unit 200 sets both the “interrupt” flag 252 and the “return” flag 253 to “off”, and further sets the count value stored in the count value storage unit 258 to “1” (step S101, S102, S103). Then, as shown in the schematic diagrams of FIGS. 14A to 14C, the control unit 200 displays the paper direction designation screen 23 on the display unit 221 (step S104).

  FIG. 14A to FIG. 14C are schematic diagrams showing transition of the display state of the paper direction designation screen 23, and FIG. 14A shows the initial screen displayed in step S104. A direction order display screen 30 is displayed near the upper portion of the paper direction designation screen 23, and an “upper index” button 111U, a “lower index” button 111D, a “left index” button 111L, and “ A “right index” button 111R, a “cancel” button 105, and a “return” button 108 are displayed. Note that the initial screen of the paper direction designation screen 23 shown in FIG. 14A is the first of the three times. Specifically, the number of readings is set to “3 times” in the previous reading number specifying process. It is displayed that this is a screen for designating the reading direction of the document (paper) at the time of the first reading when designated.

15 (a) to 15 (d) are schematic diagrams showing index marks displayed on the direction order display screen 30. FIG. The upper index mark 31U shown in FIG. 15A is placed by the user with the upper end of the document (paper) positioned on the document table of the reading unit 212 on the upper side (back side) as viewed from the user. Is displayed on the direction order display screen 30 when the “upper index” button 111U is pressed to designate the button. The lower index mark 31D shown in FIG. 15B is placed by the user with the upper end of the document (paper) positioned on the document table of the reading unit 212 on the lower side (front side) as viewed from the user. This is displayed on the direction order display screen 30 when the “lower index” button 111D is pressed to designate this. The left index mark 31L shown in FIG. 15C indicates that the user places the upper end of the document (paper) on the document table of the reading unit 212 on the left side when viewed from the user. Is displayed on the direction order display screen 30 when the “left index” button 111L is pressed.
The right index mark 31R shown in FIG. 15D indicates that the user places the upper end of the document (paper) on the document table of the reading unit 212 on the right side when viewed from the user. Is displayed on the direction order display screen 30 when the “right index” button 111R is pressed. In either case, however, the document (paper) is placed on the document table of the reading unit 212 upside down when viewed from the user.

  First, the control unit 200 determines whether any one of the “upper index” button 111U, the “lower index” button 111D, the “left index” button 111L, and the “right index” button 111R is pressed (step S105, S106, S107, S108).

  When the “upper index” button 111U is pressed (YES in step S105), the control unit 200 determines that it is designated to place the upper end portion of the document upward (backward). In this case, the control unit 200 displays the upper index mark 31U shown in FIG. 15A on the direction order display screen 30 (step S109), and stores “upward” information in the designated sheet direction storage unit 255 (step S109). S110).

  When the “down index” button 111D is pressed (YES in step S106), the control unit 200 determines that it is designated to place the upper end portion of the document downward (frontward). In this case, the control unit 200 displays the lower index mark 31D shown in FIG. 15B on the direction order display screen 30 (step S111), and stores “downward” information in the designated sheet direction storage unit 255 (step S111). S112).

  When the “left index” button 111L is pressed (YES in step S107), the control unit 200 determines that it is designated to place the upper end portion of the document in the left direction. In this case, the control unit 200 displays the left index mark 31L shown in FIG. 15C on the direction order display screen 30 (step S113), and stores the “left direction” information in the designated sheet direction storage unit 255 (step S113). Step S114).

  When the “right index” button 111R is pressed (YES in step S108), the control unit 200 determines that it is designated to place the upper end portion of the document in the right direction. In this case, the control unit 200 displays the right index mark 31R shown in FIG. 15D on the direction order display screen 30 (step S115), and stores “right direction” information in the designated sheet direction storage unit 255 (step S115). S116). FIG. 14B illustrates a state in which “right direction” is designated as the reading direction at the time of the first reading. In the paper direction designation screen 23 shown in FIG. 14B, the next is the designation of the reading direction at the time of the second reading, specifically, “3 times” specified in the previous reading number specifying process. The screen for specifying the reading direction of the original (paper) at the time of the second reading after the specification of the reading direction of the original (paper) at the time of the second reading is completed. Is displayed.

  As described above, when any one of the “upper index” button 111U, the “lower index” button 111D, the “left index” button 111L, and the “right index” button 111R is pressed, the control unit 200 counts the count value storage unit 258. Is incremented by "1" (step S117). Then, the control unit 200 sets the incremented count value stored in the count value storage unit 258 as “n” of “n-th” as shown in FIGS. 14 (a) to 14 (c). indicate.

  In addition, the control unit 200 compares the incremented count value stored in the count value storage unit 258 with the designated reading number value stored in the designated reading number storage unit 256 (step S118), and the count value. When the count value stored in the storage unit 258 exceeds the specified reading number value (in this example, “3”) stored in the specified reading number storage unit 256, that is, the specification specified in the reading number specifying process If the paper direction designation for the number of readings has been completed (YES in step S118), the paper direction designation process is terminated and the process returns to the main routine of the encryption process. On the other hand, when the incremented count value stored in the count value storage unit 258 is less than or equal to the specified reading number value stored in the specified reading number storage unit 256, that is, the specified reading number specified in the reading number specifying process. If the paper direction designation for the minute has not been completed (NO in step S118), the control unit 200 returns the process to step S105, and repeats the above-described process of determining whether any button has been pressed again. To do.

  When none of “upper index” button 111U, “lower index” button 111D, “left index” button 111L, and “right index” button 111R is pressed (NO in steps S105, S106, S107, and S108), the control unit 200 determines whether any of the “return” button 108 or the “cancel” button 105 has been pressed (steps S119 and S120).

  When the “return” button 108 is pressed (YES in step S119), the control unit 200 sets the “return” flag 253 to “on” (step S121), ends the paper direction designation processing, and performs encryption. Return to the main routine of processing. When the “cancel” button 105 is pressed (YES in step S120), the control unit 200 sets the “suspend” flag 252 to “on” (step S122), ends the paper direction designation processing, and performs the encryption processing. Return to the main routine.

  In the paper direction designation screen 23 shown in FIG. 14 (c), as a result of the paper direction designation processing as described above, the direction indicator display screen 30 includes the right index mark 31R, the lower index mark 31D, and the upper index mark 31U. A state in which three index marks are displayed in order is shown. That is, the direction order display screen 30 shown in FIG. 14 (c) displays that the user has specified that the original (paper) is to be read rightward for the first time, downward for the second time, and upward for the third time. is doing. In FIG. 14C, “fourth” is displayed for the three designated reading times. Therefore, in this case, the determination result in step S118 is “YES”, and the process is automatically returned to the main routine of the encryption process.

  When the process returns from the paper orientation designation subroutine shown in the flowchart of FIG. 13 to the main routine of the encryption process shown in the flowchart of FIG. 5, the control unit 200 first confirms the setting of the “interrupt” flag 252 ( Step S18). When the setting of the “suspend” flag 252 is “on”, that is, when the user stops the encryption process (YES in step S18), the control unit 200 clears the working area 259 of the temporary storage unit 242 and specifies “2” is set as the designated reading number value in the reading number storage unit 256, the stored content of the designated sheet direction storage unit 255 is cleared (step S22), and the encryption process is terminated. However, when the “interrupt” flag 252 is “off” (NO in step S18), the control unit 200 next confirms the setting of the “return” flag 253 (step S19).

  When the “return” flag 253 is “ON”, that is, when the user interrupts the paper direction designation process and restarts the previous reading count designation process (YES in step S19), the control unit 200 proceeds to step S14. , And the processing procedure after the above-described reading number designation processing is executed again. As a result, the user can redo the operation from the designation of the number of readings. On the other hand, when the “return” flag 253 is “off” (NO in step S19), the control unit 200 advances the processing to step S20 and executes the following image data encryption processing.

  The control unit 200 encrypts the image data in the encryption designation area 16 (17) designated in the encryption area designation process among the page-unit image data to be processed stored in the image data storage unit 251. The data is sent to the unit 201 and encrypted by a conventionally known encryption method using a predetermined encryption key. Further, the control unit 200 embeds information stored in the designated reading number storage unit 256 and the designated sheet direction storage unit 255 (designated reading number value and designated sheet direction information), and a decryption key corresponding to the above encryption key. The image processing unit 204 generates image data of the area markers 11, 12, and 13. Then, the control unit 200 determines a predetermined corner among the four corners of the image data (encrypted image data such as a scrambled image) of the encryption designation area 16 (17) encrypted by the encryption processing unit 201. The image data of the area markers 11, 12, and 13 generated by the image processing unit 204 is combined with the unit (three corners excluding the lower right corner in the present embodiment). The encrypted image data obtained by synthesizing the image data of the area markers 11, 12, and 13 in this way is the encryption designation area 16 (17) of the page-unit image data to be processed stored in the image data storage unit 251. Is pasted. As a result, the encryption designation area 16 (17) becomes the encryption area 14 (15).

  Hereinafter, the area marker will be specifically described. As shown in FIG. 4 (c), images of region markers 11 (upper left), 12 (upper right), and 13 (lower left) are synthesized at three corners of the four corners of the encrypted region 14 (15). . These area markers 11, 12, and 13 not only indicate the range of the encrypted area 14 (15), but also in the image of each area marker 11, 12, and 13 at the time of the decryption process specified in the read count designation process. Read count value (designated read count value), information (designated paper direction information) indicating the reading direction at the time of each reading of the encrypted document 6 at the time of decryption processing designated in the paper direction designation processing, and further decryption A decryption key for use in processing is embedded in an unreadable state by human eyes.

  The control unit 200 reads out the image data (encrypted image data 7) of the encrypted document 6 encrypted as described above from the image data storage unit 251 and gives it to the printing unit 222, thereby printing it on an appropriate sheet. (Step S21). On the other hand, in the PC 3, as shown in FIG. 3, the page-unit image data of the document data generated by various application programs is encrypted by the encryption processing unit 301 in the same manner as in the above-described MFP 2, and the page The data generation unit 305 converts the encrypted image data 7 to be encrypted in page units. The encrypted image data 7 is transmitted to the multifunction device 2 and the general printer 4 through the network NE, for example (step S21), and printed as an encrypted document 6 on an appropriate sheet. The encrypted image data 7 generated by the PC 3 can be displayed as an image on the display unit 221 of the multifunction machine 2 as well as the display unit 321 of the PC 3, and also on the display device of the general terminal device 1. It can be displayed as an image.

  Next, the decryption process of the encrypted document 6 printed as described above will be described. Note that the decryption process of the encrypted document 6 can be performed only in the multifunction machine 2 and cannot be performed in the PC 3. However, even the encrypted document 6 created in the PC 3 can be decrypted by causing the MFP 2 to read it.

  When the MFP 2 decrypts the encrypted document 6, the number of times the encrypted document 6 is read, the reading direction of the encrypted document 6 at each reading, specifically, the document table (not shown) of the reading unit 212. The direction in which the encrypted document 6 is placed on 212P is important, in other words, it is a key for authenticating the user. FIG. 16 is a schematic diagram for explaining the definition of the paper direction when the encrypted document 6 is placed on the document table 212P of the reading unit 212.

  Generally, when a scanner or the like reads a document, the document is placed with the surface on which the image is formed (hereinafter, this surface is referred to as the front surface and the opposite surface is referred to as the back surface) toward the document table 212P. The user can see the back side of the document. Accordingly, FIGS. 16A to 16D show a state in which an image formed on the front surface is seen through when the original is viewed from the back side. As shown in FIG. 16A, the document is placed on the document table 212P by placing the upper end of the document (encrypted document 6) on the document table 212P as viewed from the user side (back side). 16B, a method of placing the document (encrypted document 6) with the upper end portion of the document (encrypted document 6) positioned on the document table 212P on the lower side (front side) as viewed from the user. 16 (c), a method of placing the document (encrypted document 6) with its upper end positioned on the document table 212P on the left side when viewed from the user, and as shown in FIG. 16 (d), the document ( There are four methods of placing the upper end of the encrypted document 6) on the document table 212P on the right side when viewed from the user (hereinafter, referred to as up, down, left, and right). The originals shown in FIGS. 16A, 16B, 16C, and 16D are hereinafter referred to as an upward original 6U, a downward original 6D, a left original 6L, and a right original 6R. .

  17 (a) to 17 (e), FIG. 18 (f), and FIG. 18 (g) show the decryption displayed on the display unit 221 of the multi-function device 2 when the encrypted document 6 is decrypted. FIG. 17 is a schematic diagram showing transition of the display state of the processing screen 24. FIGS. 17 (a) to 17 (e) show the states when the restoration is successful, and FIGS. 17 (a) to 17 (e) show the states when the processing fails. This is shown in FIG. 18 (c), FIG. 18 (f) and FIG. 18 (g). In addition, as a procedure for correct decryption processing, the schematic diagrams in FIGS. 19A to 19C are schematic diagrams illustrating an example of a procedure for reading an encrypted document in correct decryption processing. In the following, the number of times of reading is 3, and the direction in which the encrypted original 6 is placed on the original table 212P at the time of each reading is sequentially right, down, up, that is, the right-side original 6R is the second time at the first reading. An example will be described in which the downward document 6D may be read during the reading and the upward document 6U may be read during the third reading.

  20 and 21 are flowcharts showing a processing procedure for the decryption process of the encrypted document 6, and the encrypted image data in the encryption area 14 in the encrypted document 6 is decrypted and the original is processed. The image data is restored and printed, or displayed on a display device (display unit), so that the contents of the encrypted area 14 can be read by human eyes. Hereinafter, the decrypting process of the encrypted document 6 will be described with reference to the flowcharts shown in FIGS.

  When the decoding process is started in the multifunction device 2, the control unit 200 first clears the count value stored in the count value storage unit 258, that is, sets it to “0” (step S201). In this decryption process, the count value stored in the count value storage unit 258 is used to count how many times the encrypted document 6 has been actually read. Therefore, “0” needs to be set as the count value as described above at the start of the decoding process.

  Next, the control unit 200 clears the designated sheet direction information that is stored in the reading sheet direction storage unit 257 (step S202). The reading sheet direction storage unit 257 is a storage area for sequentially storing information on the direction in which the document 6 is placed on the document table 212P (designated sheet direction information) every time the encrypted document 6 is actually read. Therefore, as an initial setting for the decoding process, nothing needs to be stored. Next, the control unit 200 displays the decryption processing screen 24 on the display unit 221 (step S203). In step S203, the initial screen of the decryption processing screen 24 shown in the schematic diagram of FIG. 17A is displayed.

  As shown in FIGS. 17 (a) to 17 (d) and FIG. 18 (f), on the decryption processing screen 24, a direction order display screen 30 is displayed in the upper portion, and “ A “read” button 109, a “cancel” button 105, and an “end” button 110 are displayed. Note that the initial screen of the decryption processing screen 24 shown in FIG. 17A is the “first” reading process, specifically, the “three times” specified in the previous reading number specifying process. It is displayed that this is a screen for performing the first reading process within the designated number of readings.

  Next, the control unit 200 confirms that the document (encrypted document 6) has been placed (set) on the document table 212P by the user (step S204). This confirmation can be made by a sensor (not shown) provided on the document table 212P. By the way, the direction in which the encrypted document 6 is placed on the document table 212P is known only by the user who created the encrypted document 6 (or the user who is informed by the user who created the encrypted document 6). The user places the encrypted document 6 on the document table 212P in the correct direction for the first reading, in other words, in the direction designated by the user as the first sheet direction in the sheet direction designating process.

  After the encrypted document 6 is placed on the document table 212P, the control unit 200 determines whether any one of the “read” button 109, the “cancel” button 105, and the “end” button 110 is pressed (step). S205, S206, S207). When the “read” button 109 is pressed (YES in step S205), the control unit 200 causes the reading unit 212 to read the image of the encrypted document 6 placed on the document table 212P, and causes the page unit to be read. Image data is generated and stored in the image data storage unit 251 (step S208). Next, the control unit 200 causes the marker recognition unit 202 to recognize the image data of the region markers 11, 12, and 13 included in the image data stored in the image data storage unit 251 as described above (step S209).

  The area markers 11, 12, and 13 are formed only at predetermined three corners of the four corners of the rectangular area of one encryption area 14 (15). When the marker recognition unit 202 first recognizes the positions of these three area markers 11, 12, and 13, the area markers 11, 12, and 13 are located at any of the four corners of the encryption area 14. Whether or not it is formed is determined, and thereby the direction of the encrypted area 14 (15), that is, the reading direction of the read encrypted document 6 is determined. Therefore, next, if necessary, the control unit 200 once reads out the entire page unit image data stored in the image data storage unit 251 so that the upper part of the encryption area 14 becomes the upper part of the image. The image processing unit 204 performs rotation processing so that the upper part of the image data in page units is in the correct direction (step S210), and the encrypted image data in the correct direction is stored in the image data storage unit 251 (step S211). ). However, when the original 6 is read for the second time and thereafter, the same original is read although the direction is different. Therefore, it is necessary to store the image data in the image data storage unit 251 or rotate the image data. There is no need to let them.

  In addition, the control unit 200 determines the size of the encryption area 14 (15) and the page-unit image data (encrypted document 6) from the positions of the three area markers 11, 12, 13 on the image data in the correct direction. Since the above position is also found, such information is stored in the working area 259 of the temporary storage unit 242 (step S212). Since various information necessary for the decoding process is read from the information embedded in each of the area markers 11, 12, and 13, the control unit 200 stores the information in the temporary storage unit 242 (step S213). ).

  The information stored in the temporary storage unit 242 in this step S213 is as follows. Since the designated number-of-reads value and the designated sheet direction information designated when the document is encrypted are read by the marker recognition unit 202, the control unit 200 stores them in the designated number-of-reads storage unit 256 and the designated sheet direction storage unit 255, respectively. Remember me. Further, a decryption key corresponding to the encryption key used when the encryption area 14 (15) of the encrypted document 6 is encrypted is read by the marker recognition unit 202 and stored in the working area 259.

  Next, the control unit 200 determines the direction of the image data obtained when the direction of the encryption area 14 is first determined, that is, when the document is actually placed on the document table 212P and read by the reading unit 212. The direction is stored in the reading sheet direction storage unit 257 as reading direction information (step S214).

  Note that the decryption key is provided in advance on the multifunction device 2 side as a spare for future system expansion or individually, but in principle, the decryption key obtained from the area marker of the encrypted document 6 is used. Is used preferentially. The positional relationship between the area markers 11, 12, and 13 can also be used to determine the degree of inclination of the encrypted document 6 when the encrypted document 6 is read.

  In the second and subsequent readings of the same encrypted document 6, since the same document is actually read even if the directions are different, only the actual reading direction (reading direction information) is associated with the number of readings. Thus, it may be stored only in the reading sheet direction storage unit 257.

  Next, the control unit 200 displays the upper index mark 31U shown in FIG. 15 on the direction order display screen 30 in order to indicate to the user in which direction the read encrypted document 6 is placed on the document table 212P. , The lower index mark 31D, the left index mark 31L, and the right index mark 31R are displayed with marks corresponding to the reading direction information stored in the reading sheet direction storage unit 257 (step S215).

  When the first reading of the encrypted document 6 and various processes related thereto are completed as described above, the control unit 200 increments the count value stored in the count value storage unit 258 by “1” (step S216). ), The process returns to step S204 to wait for the next reading process. In this state, as shown in FIG. 17 (b), a display is displayed on the decoding processing screen 24 to indicate to the user that the “second” reading process will be performed. Thereafter, when the encrypted document 6 is placed again on the document table 212P and the “read” button 109 is pressed, the same processing as described above is performed. Therefore, if the user repeatedly reads the same encrypted document 6 while placing it on the document table 212P while causing the reading unit 212 to read it repeatedly, the decryption processing screen 24 is displayed from the state shown in FIG. Transition is made to the state shown in FIG. 17 (c) and FIG. 17 (d), or to the state shown in FIG. 17 (c) and FIG. 18 (f).

  Accordingly, when the first reading is completed, only the right index mark 31R is displayed as shown in FIG. 17 (b), but each time the second and subsequent readings are completed, the sequential reading of FIG. 17 (c) is performed. 17 (d) or 18 (f), any one of the index marks 31U, 31D, 31L, 31R is sequentially added and displayed on the direction order display screen 30. The user can confirm the designated number of times of reading that he / she remembers and the reading direction at the time of reading by visually recognizing the indicator marks which are sequentially added and displayed on the direction order display screen 30. Can do.

  When the “end” button 110 is pressed without pressing the “read” button 109 (NO in steps S205 and S206, YES in step S207), the control unit 200 reads the number of times necessary for the decryption process. It is determined whether or not it has been performed (step S217). Specifically, the designated reading count value obtained from the information embedded in the marker areas 11, 12, and 13 and stored in the designated reading count storage unit 256 and the actual reading count, that is, the count value storage unit The count value stored in 258 is compared.

  The number of times the reading unit 212 actually read the encrypted document 6, that is, the count value stored in the count value storage unit 258, is stored in the number of readings necessary for the decryption processing, that is, the designated reading number storage unit 256. If it matches the designated reading count value (YES in step S217), the control unit 200 obtains the designated sheet direction information (obtained from the information embedded in the area marker) stored in the designated sheet direction storage unit 255. The sheet direction specified in the sheet direction specifying process) is compared with the reading direction information stored in the reading sheet direction storage unit 257 (the order of the sheet direction when the document is actually read a plurality of times) ( Step S218), it is determined whether or not they match. As a result, if the designated sheet direction information matches the reading direction information (YES in step S218), the control unit 200 performs the decryption process of the encrypted document 6 (step S220).

  The procedure of the decryption process is specifically as follows. The control unit 200 uses the decryption key previously obtained from the area markers 11, 12, and 13 and stored in the working area 259 of the temporary storage unit 242, for each page stored in the image data storage unit 251. The encrypted image data in the encrypted area 14 (15) in the image data is decrypted to restore the original image data, and the restored image data is pasted on the original encrypted area 14 (15). wear. At this time, if a plurality of encryption areas exist in the same encrypted document 6 and different decryption keys are required corresponding to the respective encryption areas, the area markers 11 and 12 in the respective encryption areas are used. , 13 can obtain the necessary decryption keys. Therefore, in such a case, the control unit 200 decrypts the image data in each encrypted area using a decryption key as necessary.

  If the comparison result of the number of readings in step S217 does not match even though the “end” button 110 has been pressed (NO in step S217), an unauthorized user other than the user who created the encrypted document 6 has detected. It is determined that the encrypted document 6 is to be decrypted. Therefore, in such a case, the control unit 200 displays an error message 32 as shown in the schematic diagram of FIG. 18 (g) on the decryption processing screen 24 as an error occurrence (step S219). After displaying the error message 32, the control unit 200 confirms that the “confirm” button 112 shown in FIG. 18 (g) has been pressed, and then performs this decoding process without performing the decoding process. finish.

  On the other hand, if the order of the paper directions does not match (NO in step S218), the control unit 200 still generates an error and displays an error message 32 as shown in the schematic diagram of FIG. It is displayed (step S219). After displaying the error message 32, the control unit 200 confirms that the “confirm” button 112 shown in FIG. 18 (g) has been pressed, and then performs this decryption process without performing the decryption process. finish.

  Even if the number of readings is the same and the order in the paper direction is also the same (both YES in steps S217 and S218), the encryption area 14 (15) is soiled or falsified and cannot be correctly decrypted. There is also a possibility (NO in step S221). In such a case, the control unit 200 also displays an error message 32 as shown in the schematic diagram of FIG. 18 (g) on the decryption processing screen 24 as an error has occurred (step S219). After displaying the error message 32, the control unit 200 confirms that the “confirm” button 112 shown in FIG. 18 (g) has been pressed, and then performs this decryption process without performing the decryption process. finish.

  If the encrypted area 14 (15) has been correctly decrypted (YES in step S221), the unencrypted image data 8 after decryption is printed as the unencrypted document 5 or unencrypted. The control unit 200 generates a “print” button 113 and a “transfer” button 114 and further a “cancel” button 105 for allowing the user to select whether to transfer the image data 8 to another terminal device. Is displayed as shown in the schematic diagram of FIG. 17E (step S222).

  Although the decryption process itself is completed as described above, when the “print” button 113 is pressed, the control unit 200 gives the decrypted unencrypted image data 8 to the printing unit 222, so that an appropriate paper sheet is obtained. Are printed as a printed matter (unencrypted document 5). In addition, when the “transfer” button 114 is pressed, the control unit 200 uses the terminal separately designated by the user as the unencrypted image data 8 as a file in a general electronic file format such as pdf format or tiff format. Transfer to device.

  When the “Cancel” button 105 is pressed on the screen shown in FIG. 17 (e), the control unit 200 displays an error message 32 as shown in FIG. 18 (g) as an error, and the “Confirm” button. After confirming that 112 is pressed, the decoding process is terminated.

1 is a block diagram showing an embodiment of a configuration example of an image forming apparatus according to the present invention. 1 is a block diagram showing an embodiment of a configuration example of an image forming apparatus according to the present invention. FIG. 4 is a schematic diagram illustrating the flow of image data and printed matter when the image forming apparatus according to the present invention is used. It is a schematic diagram for explaining an outline of image processing by the image forming apparatus of the present invention. 4 is a flowchart showing a processing procedure of a main routine (encryption processing main routine) for the image forming apparatus of the present invention to create an encrypted document in which a designated area of a non-encrypted document is encrypted. 6 is a flowchart showing a procedure of encryption area designation processing by the image forming apparatus of the present invention. 6 is a flowchart showing a procedure of encryption area designation processing by the image forming apparatus of the present invention. 6 is a flowchart showing a procedure of encryption area designation processing by the image forming apparatus of the present invention. FIG. 6 is a schematic diagram showing transition of the display state of an encryption area designation screen of the image forming apparatus of the present invention. It is a schematic diagram which shows the coordinate system for the display on the screen of the display part of the frame of the encryption designation | designated area | region of the image forming apparatus of this invention. 5 is a flowchart illustrating a procedure of reading count designation processing by the image forming apparatus of the present invention. FIG. 6 is a schematic diagram of a reading count designation screen of the image forming apparatus of the present invention. 6 is a flowchart illustrating a procedure of paper direction designation processing by the image forming apparatus of the present invention. FIG. 6 is a schematic diagram illustrating transition of a display state of a sheet direction designation screen of the image forming apparatus of the present invention. It is a schematic diagram showing each index mark displayed on the direction order display screen by the image forming apparatus of the present invention. FIG. 4 is a schematic diagram for explaining a definition of a sheet direction when the image forming apparatus of the present invention places an encrypted document on a document table of a reading unit. FIG. 10 is a schematic diagram illustrating a transition of a decryption processing screen display state when the image forming apparatus of the present invention performs decryption processing of an encrypted document. FIG. 10 is a schematic diagram illustrating a transition of a decryption processing screen display state when the image forming apparatus of the present invention performs decryption processing of an encrypted document. FIG. 10 is a schematic diagram illustrating an example of a procedure for reading an encrypted document in a correct decryption process by the image forming apparatus of the present invention. 6 is a flowchart illustrating a processing procedure for decrypting an encrypted document by the image forming apparatus of the present invention. 6 is a flowchart illustrating a processing procedure for decrypting an encrypted document by the image forming apparatus of the present invention.

Explanation of symbols

1 External terminal device 2 Multifunction machine 3 PC (personal computer)
4 External printer 5 Unencrypted document 6 Encrypted document
7 Encrypted image data
8 Unencrypted image data
14 Encryption specification area
15 Encryption designation area 16 Encryption area 17 Encryption area 200, 300 Control unit 201, 301 Encryption processing unit 202 Marker recognition unit 203 Decoding processing unit 204, 304 Image processing unit 212 Reading unit 221, 321 Display unit 222 Printing 251, 351 Image data storage unit 255, 355 Specified paper direction storage unit 256, 356 Specified reading count storage unit 257 Reading paper direction storage unit 258, 358 Count value storage unit

Claims (10)

In an image forming apparatus comprising: a reading unit that reads an image of a document to generate image data in units of pages; and an image forming unit that forms an image of image data on a sheet in units of pages.
An area designation accepting means for accepting designation of an area of an arbitrary size at an arbitrary position in image data in page units on which the image forming means is to form an image;
Encryption processing means for encrypting image data of an arbitrary area for which designation is accepted by the area designation receiving means with a predetermined encryption key;
A reading condition designating unit for designating a reading condition in which the number of readings by the reading unit and a reading direction at the time of each reading are combined with encrypted image data in units of pages including an area encrypted by the encryption processing unit;
A determination unit that determines whether or not the reading unit has read a document in which the image forming unit forms an image of encrypted image data in units of pages on a sheet according to a reading condition specified by the reading condition specifying unit;
When the determination unit determines that the document has been read by the reading unit in accordance with the reading condition specified by the reading condition specifying unit, the encrypted area included in the page unit image data generated by the reading unit An image forming apparatus comprising: decryption processing means for restoring image data with a decryption key corresponding to the predetermined encryption key. A display means,
The page unit encrypted image data and / or the image data of the encrypted area is displayed on the display unit as image data of the page unit restored by the decryption processing unit. The image forming apparatus according to claim 1.   2. The image according to claim 1, wherein the image forming apparatus is configured to form an image on the external image forming apparatus by transferring the encrypted image data in page units to the external image forming apparatus via a communication line. Forming equipment.   By transferring the page-unit image data restored by the decryption processing means to the external display device via the communication line, the page-unit encrypted image data and / or the encrypted area image data, 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is displayed as an image on an external display device. In an image forming apparatus comprising image data generating means for generating image data in units of pages that can be formed on a sheet by an external image forming apparatus,
Area designation accepting means for accepting designation of an area of an arbitrary size at an arbitrary position in the page-unit image data generated by the image data generating means;
Encryption processing means for encrypting image data of an arbitrary area for which designation is accepted by the area designation receiving means with a predetermined encryption key;
The encrypted image data of the page unit including the area encrypted by the encryption processing means is encrypted when the external reading device reads a document image-formed on a sheet by an external image forming device. Reading condition designating means for designating a reading condition that combines the number of times of reading by an external reading device and the reading direction at the time of reading as a condition for restoring the image data of the area with a decryption key corresponding to the predetermined encryption key An image forming apparatus comprising: A display means,
6. The image forming apparatus according to claim 5, wherein the encrypted image data for each page is displayed on the display unit as an image.   6. The image formation according to claim 5, wherein the encrypted image data in units of pages is transferred to an external display device via a communication line so as to be displayed as an image on the external display device. apparatus.   The encryption processing means encrypts the reading condition specified by the reading condition specifying means when the image data of the area received by the area specification receiving means is encrypted with the predetermined encryption key. The image forming apparatus according to claim 1, wherein the image forming apparatus is included in the image forming apparatus.   The encryption processing means includes the decryption key in the encrypted image data when encrypting the image data of the area that has been designated by the area designation accepting means with the predetermined encryption key. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The area designation accepting means accepts designation of a rectangular area,
The encryption processing unit determines whether the region designation receiving unit encrypts the image data in the region for which the designation is received, and determines whether it is up, down, left, or right in at least one of the four corners of the rectangular region that has received the designation. An image forming apparatus according to any one of claims 1 to 9, wherein a marker is added for the purpose.

Images