JPWO2008146504A1 - Image processing system - Google Patents

Abstract

To provide an image processing system that can easily perform image processing such as encryption and decryption without taking the user to create an image to be processed, in order to render the contents of electronic data A drawing information input receiving unit 21 for receiving the drawing information input, a digital image generating unit 15 for generating a digital image based on the received drawing information, and a partial area to be encrypted in the generated digital image. A definition information acquisition unit 23 for acquiring definition information including area specifying information for specifying and key information used when encrypting the partial area, and converting an image of the partial area based on the key information. An encryption unit 11 that generates an encrypted image and an output unit 12 that outputs the encrypted image are provided.

Description

  The present invention relates to a technique for encrypting electronic data.

  As a technology dealing with encryption of printed matter, the entire image is first divided into a plurality of blocks, the images of the divided blocks are rearranged based on the parameters obtained from the input password (encryption key), and the image of the block specified by the parameters There is a technique for encrypting an image by reversing black and white and mirror reversal (see Patent Document 1). When decrypting an encrypted image, a positioning frame is added to the outside of the image, a password (decryption key) is input, and then the original image is decrypted in the reverse procedure of encryption.

In addition, there is a technique in which black and white squares of a predetermined size representing binary data are arranged in a matrix and embedded in a printed material (see Patent Document 2). Further, a positioning symbol is added to the printed matter at a predetermined position in the matrix so that the imaged position can be known at the time of decoding. Using this positioning symbol as a reference, an image is taken with a scanner or camera, and the embedded information is decoded.
Japanese Patent Application Laid-Open No. 8-17989 Japanese Patent No. 2938338

  Conventionally, there is a technique for performing image processing based on an encryption key to encrypt an image. However, when encrypting an image, it is necessary to capture the scanner if the document is a paper medium. If the document is an electronic data document, an image as a set of pixels (such as a bitmap format image) is generated. It is necessary to do. In particular, in an electronic data document, if an application that handles the document does not have an output function in an image format, it is difficult to obtain an image for encryption, and it is difficult for the user to perform encryption. It will be time consuming.

  In view of the above-described problems, the present invention provides an image processing system capable of easily performing image processing such as encryption and decryption without requiring the user to create an image to be processed. And

  The present invention employs the following means in order to solve the above-described problems. That is, the present invention provides a drawing information input receiving means for receiving drawing information input for drawing the contents of electronic data, and a set of pixels based on the drawing information received by the drawing information input receiving means. A digital image generating means for generating a digital image, area designation information for specifying a partial area to be encrypted in the digital image generated by the digital image generating means, and encrypting the partial area Definition information acquisition means for acquiring definition information including key information used at the time, and by converting an image of the partial area specified based on the area designation information based on the key information, An encryption unit for generating an encrypted image obtained by encrypting an image of the area, and a content corresponding to the content of the electronic data generated by the encryption unit. And output means for outputting the encrypted image is an image processing system comprising a.

  Here, the electronic data refers to data including some information such as documents, charts, and illustrations. Such electronic data is created as an electronic file by, for example, a document creation application, a spreadsheet application, an illustration creation application, or the like. The digital image generating means generates an image when displaying or printing electronic data as a digital image (for example, bitmap data) as a set of pixels by using the drawing information received by the drawing information input receiving means. To do. The drawing information is information for designating characters, format information, layout, and the like for displaying electronic data on a display or printing on a paper medium. That is, according to the present invention, even when an application that handles electronic data does not support image output, the encryption key is used without requiring the user to create a digital image for use in encryption processing. Image processing such as encryption and decryption can be easily performed.

  In the encryption according to the present invention, it is possible to specify and encrypt a partial area of a digital image. Here, in the present invention, the partial area to be encrypted is designated using the area designation information. The area designation information includes information for specifying an area on the digital image. Information for specifying the region includes position information, size information, vector information, and the like.

  The present invention also provides an encrypted image acquisition means for acquiring an encrypted image generated by converting at least a part of a digital image as a set of pixels based on an encryption key, and decryption in the encrypted image Definition information acquisition means for acquiring definition information including region specification information for specifying a decryption region to be subject to decryption and a decryption key used for decrypting the partial region, and specification based on the region specification information A decoding means for generating a digital image obtained by decoding the image in the decoding area by converting the image in the decoding area based on the decoding key, and outputting the digital image generated by the decoding means And an output means.

  As a result, by encrypting the information that you want to restrict browsing, you can use the decryption key to decrypt and output the original digital image while restricting the browsing of important information for those who do not have browsing authority By doing so, it becomes possible to permit browsing of information to a person having browsing authority. According to the image processing system of the present invention, since the encrypted information is an image, only important information is encrypted and displayed on a display or the like, or printed on a paper medium and circulated. In addition, the encrypted part can be restored (decrypted) when necessary.

  Here, the encryption means, for example, converts the image of the partial area into a processed image based on key information, and regularly converts the pixel value of the processed image, thereby encrypting at the time of decryption. Generating the encrypted image including a converted image having regularity used for specifying a position, and the decoding means detects an encrypted position in which pixel values are regularly converted in the decryption area; The decryption area is decrypted into a digital image based on the encrypted position and the decryption key. Since the pixel values are regularly converted during the encryption process, the encrypted position can be detected based on the regularity during the decryption process, thereby enabling highly accurate decryption.

  The image processing system according to the present invention further comprises definition information holding means for holding a plurality of predefined definition information in association with identification information for identifying the definition information, wherein the definition information acquisition means The region designation used for generation of an encrypted image by the encryption unit or generation of a digital image by the decryption unit from a plurality of the definition information held by the definition information holding unit based on the identification information The definition information including information and the key information may be acquired.

  As a result, a plurality of definition information can be defined in advance, and appropriate definition information can be acquired and used for each encryption or decryption image processing.

  Here, the image processing system according to the present invention includes a user-specified content holding unit that holds identification information related to the definition information designated in advance by a user among the plurality of definition information held by the definition information holding unit. The definition information acquisition unit may acquire the definition information related to the identification information held by the user-specified content holding unit from a plurality of the definition information held by the definition information holding unit. Good.

  As a result, a large amount of electronic data can be continuously encrypted or decrypted without having to select definition information each time encryption processing or decryption processing, or newly set region designation information or key information.

  In addition, the image processing system according to the present invention provides an identification information acquisition for acquiring the identification information from the digital image generated by the digital image generation unit or the encrypted image acquired by the encrypted image acquisition unit. And the definition information acquisition means may acquire the definition information related to the identification information acquired by the identification information acquisition means from a plurality of the definition information held by the definition information holding means. Good.

  By acquiring the identification information included in the digital image or the encrypted image and acquiring the definition information related to this identification information, the user can use any definition information from the contents of the image to be encrypted or decrypted. It is possible to perform image processing without having to determine whether encryption or decryption should be performed and select definition information.

  Here, the identification information acquisition unit acquires the identification information by detecting at least one of characters, symbols, patterns, and colors included in the digital image or the encrypted image, for example. More specifically, the identification information acquisition unit may acquire identification information from a barcode, character string, symbol, or the like in the image.

  The present invention also provides a digital image generating means for generating a digital image as a set of pixels based on electronic data, and a partial area to be encrypted in the digital image generated by the digital image generating means. An encryption area specifying means for specifying, an image converting means for converting an image of the partial area specified by the encryption area specifying means into a processed image based on an encryption key, and a processed image converted by the image converting means The pixel values are regularly converted to generate a converted image having regularity used for specifying the position of the partial area at the time of decoding, and processed by the pixel value conversion means Output means for outputting an encrypted image including a converted image, and the encrypted area specifying means is an area for specifying an area on the digital image. The region indicated by the constant information is designated as the partial area to be encrypted, an electronic data encryption system.

  Here, the electronic data refers to data including some information such as documents, charts, and illustrations. In the present invention, an encrypted image is generated and output by the encryption area designating unit, the image converting unit, and the pixel value converting unit based on the digital image.

  The electronic data encryption system according to the present invention may further include region designation information acquisition means for acquiring the region specification information based on information included in the electronic data.

  Here, the information included in the electronic data may be information directly browsed by the user, that is, information directly related to a document, a chart, an illustration, or the like, or information about the electronic data, that is, so-called information. It may be metadata. By acquiring the area designation information based on such information, it is possible to configure an electronic data encryption system in which optimum area designation information is automatically selected simply by designating electronic data.

  For example, the electronic data encryption system of the present invention further comprises area designation information holding means for holding the area designation information in association with identification information for identifying the area designation information, and the area designation information acquisition means includes: Of the area designation information held by the area designation information holding means, the area designation information associated with the input identification information may be acquired.

  The identification information is information associated with each of the plurality of types of area designation information so that each area designation information can be identified, and is information used for designating the area designation information when designating the encryption target area. It is.

  The electronic data encryption system of the present invention further includes identification information acquisition means for acquiring the identification information included in the electronic data, and the area designation information acquisition means is held by the area designation information holding means. Of the area designation information, the area designation information associated with the identification information acquired by the identification information acquisition means may be acquired.

  By acquiring the identification information included in the electronic data, it is possible to associate the electronic data with region designation information indicating which part of the digital image generated based on the electronic data should be encrypted. It becomes possible.

  The electronic data encryption system according to the present invention further includes a keyword detection unit that detects the keyword included in the electronic data by comparing a character string in the electronic data with a keyword that is a predetermined character string. Further, the area designation information acquisition unit may acquire the area designation information by generating the area designation information for specifying an area corresponding to the keyword detected by the keyword detection unit.

  In addition to the important information itself, it is preferable to use a character string (for example, “address” or “name”) in which the important information is written before and after the keyword. In this way, multiple types of area designation information are prepared in advance, and important information is recorded in the digital image generated based on the electronic data without performing the operation of selecting the area designation information at the time of encryption. It is possible to automatically encrypt the area that is presumed to have been performed.

  In the present invention, the area designation information acquisition unit acquires the area designation information for designating a first partial area and a second partial area to be encrypted, and the image conversion unit The partial area and the second partial area may be converted into processed images based on different encryption keys.

  That is, according to the present invention, by using different encryption keys for encryption in different areas, it is possible to perform electronic data encryption with access control using the encryption key and security level setting. It becomes.

  The present invention also provides an encrypted image acquisition unit that acquires an encrypted image on a paper medium by imaging the paper medium, and the encrypted image acquired by the encrypted image acquisition unit. A decoding area designating unit for designating an area as a decoding area to be decrypted, and encryption for detecting an encryption position in which pixel values are regularly converted in the decoding area designated by the decoding area designating unit A position detection unit; a decryption unit that decrypts the decryption area into a digital image based on the encrypted position and the decryption key detected by the encrypted position detection unit; and a character in the digital image decrypted by the decryption unit. Electronic data generating means for detecting and specifying the electronic data, and generating electronic data including characters in the digital image as character information based on a character code. Means a region indicated by the region designation information for specifying an area on the encrypted image is designated as decryption area, an electronic data decoding system.

  By detecting and specifying characters in the decrypted digital image and generating electronic data including the characters in the digital image as character information based on character codes, electronic data that is the same as or approximate to the electronic data before encryption is obtained. Restored. That is, according to the present invention, the decrypted information can be handled as electronic data, and convenience is improved.

  Furthermore, the present invention can also be grasped as a method executed by a computer or a program for causing a computer to function as each of the above means. Further, the present invention may be a program in which such a program is recorded on a recording medium readable by a computer, other devices, machines, or the like. Here, a computer-readable recording medium is a recording medium that stores information such as data and programs by electrical, magnetic, optical, mechanical, or chemical action and can be read from a computer or the like. Say.

  According to the present invention, it is possible to provide an image processing system that can easily perform image processing such as encryption and decryption without requiring the user to create an image to be processed.

It is a figure showing the outline of the hardware constitutions of the image processing system concerning an embodiment. 1 is a diagram illustrating an outline of a functional configuration of an image processing system according to an embodiment. It is a figure which shows the positioning of the image processing program in embodiment. It is a figure which shows the structure of the definition information table in embodiment. It is a flowchart which shows the flow of a predefined process in embodiment. In an embodiment, it is a figure showing a preview screen of electronic data displayed for field specification. It is a figure which shows the definition information setting interface displayed on a display in order to set definition information in embodiment. It is a flowchart which shows the flow of the definition information designation | designated process in embodiment. It is a flowchart which shows the flow of the encryption process in embodiment. It is a flowchart which shows the flow of the decoding process in embodiment. In an embodiment, it is a figure showing a preview screen of an encryption picture displayed for decoding field specification. It is a figure which shows the outline of a function structure of the electronic data encryption system which concerns on embodiment. It is a figure which shows the position of the electronic data encryption program in embodiment. It is a figure which shows the structure of the area | region designation | designated information table in embodiment. It is a flowchart which shows the flow of the electronic data encryption in embodiment. It is a figure which shows the outline of a function structure of the electronic data decoding system which concerns on embodiment. It is a flowchart which shows the flow of the electronic data decoding process in embodiment. It is a figure which shows the outline of a function structure of the electronic data encryption system which concerns on embodiment. It is a figure which shows the example of the electronic data in which identification information is contained in metadata with the information used as the object of encryption. It is a flowchart which shows the flow of the electronic data encryption in embodiment. It is a figure which shows the outline of a function structure of the electronic data encryption system which concerns on embodiment. It is a figure which shows the display image of the electronic data containing a keyword. It is a flowchart which shows the flow of the electronic data encryption in embodiment. It is a figure which shows the display image of the electronic data encrypted using a some encryption key. It is a figure which shows the process outline | summary (the 1) of an encryption process and a decoding process. It is a figure which shows the process outline | summary (the 2) of an encryption process and a decoding process. It is a figure which shows the outline | summary of the encryption process in a 1st aspect. It is a figure which shows the example which selects an encryption area | region. It is a figure which shows the example of input of an encryption key. It is a figure which shows an example of the scramble process in an image conversion part. It is a figure which shows the other example of the scramble process in an image conversion part. It is a figure which shows the modification of the shape of the micro area | region in a scramble process. It is a figure which shows the compression process in an image conversion part. It is a figure which shows the process which images conversion data. It is a figure which shows the example (the 1) of the pixel value conversion process in a pixel value conversion part. It is a figure which shows the example (the 2) of the pixel value conversion process in a pixel value conversion part. It is a figure which shows the example of the positioning marker used by an encryption process. It is a figure which shows the example of an encryption image. This is an example in which a grayscale image is encrypted. It is a figure which shows the outline | summary of the decoding process in a 1st aspect. It is a figure which shows the process of detecting an encryption area | region from a positioning marker. It is a flowchart which shows the flow of an encryption area | region detection process. It is a figure which shows the example by which the encryption position was detected. It is a figure which shows the whole image of a 2nd aspect. It is a figure which shows the outline | summary of the encryption process in a 2nd aspect. It is a figure which shows the outline | summary of the decoding process in a 2nd aspect. It is a figure for demonstrating the detection method of an encryption area | region. It is a figure for demonstrating the detection method of an encryption position (horizontal direction). It is a figure which shows the example which detected the detection of the encryption position incorrectly. It is a figure which shows the outline | summary of the encryption process in a 3rd aspect. It is a figure which shows the outline | summary of the decoding process in a 3rd aspect.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an outline of a hardware configuration of an image processing system according to the embodiment. The image processing system 900 includes a computer 100, and a scanner 106 and a printer 107 connected to the computer 100. Here, the computer 100 includes a CPU (Central Processing Unit) 101, a main storage device such as a RAM (Random Access Memory) 102, an auxiliary storage device such as a HDD (Hard Disk Drive) 103, a ROM (Read Only Memory) 104, a display. The computer includes a display device such as 108, an input device such as a mouse 110 / keyboard 111, and a USB (Universal Serial Bus) interface 105. A scanner 106 and a printer 107 are connected to the USB interface 105.

<First embodiment>
FIG. 2 is a diagram showing an outline of a functional configuration of the image processing system 900 according to the present embodiment. The computer system shown in FIG. 1 receives drawing information for printing or display input from an external application by causing the CPU 101 to execute an image processing program read from the HDD 103 and expanded in the RAM 102. The input receiving unit 21, the digital image generating unit 15 that acquires a digital image based on the received drawing information, and the encrypting unit that generates an encrypted image by encrypting at least a part of the generated digital image 11, an output unit 12 that outputs the generated encrypted image, a definition information holding unit 22 that holds definition information including information for designating an area to be encrypted by the encryption unit 11, and definition information Definition information acquisition unit 23 that acquires definition information from the holding unit 22 and various settings and confirmation of setting contents for the user A user interface output unit 25 that provides a user interface to perform, a user input reception unit 26 that receives input from the user, a user-specified content storage unit 24 that stores information for identifying definition information specified by the user, The image processing system 900 includes an identification information acquisition unit 18 that acquires information for identifying definition information from a digital image.

  The computer system shown in FIG. 1 further executes an image processing program read from the HDD 103 and expanded in the RAM 102 in order to decrypt the encrypted image, so that the CPU 101 executes an electronic file or the like. An encrypted image acquisition unit 13 for acquiring an encrypted image from the image, a decryption unit 14 for generating a decrypted digital image by decrypting at least a part of the acquired digital image, and based on the decrypted digital image The image processing system 900 includes an electronic data generation unit 501 that generates electronic data. Note that each function unit that processes definition information, such as the definition information acquisition unit 23, the definition information storage unit 22, the user-specified content storage unit 24, and the identification information acquisition unit 18, is also used in the decryption process of the encrypted image.

  In the present embodiment, the system according to the present invention has been described as an image processing system having both encryption and decryption functions. However, the image processing system according to the present invention has an encryption function. The encryption system may be implemented as a decryption system having a decryption function.

  FIG. 3 is a diagram showing the positioning of the image processing program in the present embodiment. The image processing program provides a function corresponding to a so-called printer driver for various applications. By implementing the image processing program on the computer in this way, the electronic processing can be performed by the same operation as the normal printing process without requiring the user to generate a bitmap format digital image as a pre-encryption process. It is possible to generate an encrypted image based on the data.

  The drawing information input receiving unit 21 receives drawing information input from an application that opens some electronic data that can be encrypted, such as a document creation application or a spreadsheet application. The drawing information accepted here is information used for printing on a paper medium or the like or display on the display 108 or the like, and may include a character code, format information, vector data and pixel information for drawing, and the like.

  The digital image generation unit 15 generates a digital image in a pixel format based on the drawing information received by the drawing information input reception unit 21. The digital image generation unit 15 converts an image when electronic data related to drawing information is printed on a paper medium or the like or displayed on the display 108 or the like into a digital image in a so-called bitmap format. Normally, it consists of character code and format information if it is document data, but the encryption unit 11 encrypts the image by generating an image when the document data is displayed or printed as a bitmap format image. It becomes possible.

  The encryption unit 11 includes an encryption area designating unit 31 that designates a partial area to be encrypted in the digital image generated by the digital image generation unit 15, and an image of the designated partial area based on the encryption key. The converted image having the regularity used for specifying the position of the partial area at the time of decoding is generated by regularly converting the pixel values of the converted processed image and the image conversion unit 32 that converts the processed image into a processed image. And a pixel value conversion unit 33. Details of the encryption processing by the encryption unit 11 will be described later.

  The output unit 12 outputs an electronic file including information on the encrypted image generated by the encryption unit 11 to a storage device such as the HDD 103. However, the output may be an output to a display device such as a monitor, or a print output by the printer 107.

  The encrypted image acquisition unit 13 acquires an encrypted image from an electronic file designated by a user operation. The encrypted image acquisition unit 13 may acquire information on the paper medium as an encrypted image by imaging the paper medium using an apparatus capable of imaging the paper medium, such as the scanner 106 or a digital camera. .

  The decryption unit 14 includes a decryption region designation unit (encryption region detection unit) 142 that designates a region to be decrypted in the encrypted image acquired by the encrypted image acquisition unit 13, and a pixel in the designated decryption region An encrypted position detector 143 that detects an encrypted position in which values are regularly converted, and an inverse converter (decryption) that decrypts the decryption area into a digital image based on the detected encrypted position and decryption key. Part) 144. Details of the decoding process by the decoding unit 14 will be described later.

  The electronic data generation unit 501 detects and specifies characters in the digital image decoded by the decoding unit 14 by using a so-called OCR (Optical Character Recognition) technique, whereby the characters in the digital image are converted into characters by character codes. Electronic data included as information is generated. By generating electronic data from the decrypted digital image, electronic data that is the same as or close to the electronic data used for encryption can be obtained. The generated electronic data is preferably electronic data in a format that can be handled by the same application as the application that generated the electronic data before encryption. In addition to characters, the electronic data generation unit 501 detects and specifies formats, charts, illustrations included in digital images, and their arrangement, so that electronic data close to the electronic data before encryption is obtained. Can be generated more accurately.

  The definition information holding unit 22 includes area designation information for designating a partial area to be encrypted by position information indicating a position on the digital image, and key information (this book) used for encryption / decryption of the partial area. In the embodiment, definition information including a common key as an encryption key and a decryption key is managed in a definition information table in association with unique identification information.

  The identification information acquisition unit 18 acquires identification information included in these images from a digital image before encryption or an encrypted image before decryption in order to identify definition information used for encryption processing or decryption processing. . Here, the identification information is included in the image as, for example, a barcode, a character string, a symbol, or the like. However, the identification information may be included in electronic data or an electronic file as metadata. Also, the user-specified content holding unit 24 stores the identification information associated with the definition information specified by the user in a setting file or a registry, thereby storing the user-specified content.

  The definition information acquisition unit 23 searches the definition information table using the identification information acquired from the digital image or the encrypted image by the identification information acquisition unit 18 or the identification information held by the user-specified content holding unit 24 as a key, Get the corresponding definition information. As a result, encryption or decryption can be automatically performed using the optimum definition information without the trouble of the user selecting appropriate area designation information and the trouble of inputting appropriate key information.

  FIG. 4 is a diagram showing the configuration of the definition information table in the present embodiment. In the definition information table, definition information including area designation information including position information for indicating an area in a digital image and key information (encryption key / decryption key) used for encryption / decryption is unique. Recorded in association with identification information. The area designation information is information including position information for designating an encryption area or a decryption area in the digital image. Information used for designating the encryption area / decryption area includes position information indicating a position in the digital image, size information, vector information, and the like. The encryption area / decryption area is specified using any one or more of these pieces of information. For example, in an encryption process to be described later, three-point position information is used to designate a rectangular encryption area / decryption area. The position information can be generally expressed using units such as cm, inches, and pixels using the x-axis and the y-axis orthogonal to the x-axis (see FIG. 3). Further, the position from the end of the digital image on the x-axis and the y-axis may be indicated by a percentage (%) with the width or length of the digital image as a unit. In addition, a method of assigning a number to all the pixels of the digital image (for example, assigning a serial number from the upper left pixel to the lower right pixel) and specifying the position using this number may be considered.

  The position designated by the area designation information as the partial area to be encrypted corresponds to the position where the information to be encrypted is recorded in the electronic data that is the basis of digital image generation. For example, in document data, when personal information such as a social security number or an e-mail address is important information to be encrypted, the information is arranged in the generated digital image. An area is designated by area designation information. Therefore, the area designation information may be prepared in advance according to the format of the document data as shown in FIG. 4, or may be generated every time encryption is performed according to the contents of the document data.

  FIG. 5 is a flowchart showing the flow of the predefined process in the present embodiment. The process shown in this flowchart is a process for creating definition information including area designation information and key information used in encryption or decryption and storing it in the definition information table before encryption or decryption. Yes, triggered by the user performing an operation to instruct to perform the predefined process. The pre-definition process shown in this flowchart is performed by selecting an image processing program from a printer list in a print menu opened in an application that opens some electronic data that can be encrypted, and setting definition information here. It may be executed by instructing the start.

  In step S11 to step S13, a sample digital image or the like used for setting definition information is read and displayed, and an encryption target area and an encryption key are specified. First, the user interface output unit 25 generates a preview screen 600 including a digital image designated by the user and displays it on the display 108 (step S11).

  FIG. 6 is a diagram showing an electronic data preview screen 600 displayed for area designation in the present embodiment. On the preview screen 600, a digital image 601 used for defining definition information is displayed, and the user input receiving unit 26 is an area to be encrypted / decrypted by a range specifying operation using an input device such as the mouse 110. Is accepted (step S12). In the present embodiment, for example, the main button of the mouse 110 is pressed at a position on the digital image 601 displayed on the display 108 to be the upper left vertex of the rectangular area 602 to be encrypted, and the lower right vertex of the rectangular area 602 is The encryption target area can be designated by moving the pointer 603 on the display 108 to the desired position and releasing the main button. However, other methods may be used as a method for selecting an area to be encrypted.

  When the encryption target area is designated, the user interface output unit 25 displays a dialog for prompting input of key information on the display 108 (not shown). Here, the user input acceptance unit 26 inputs new key information (encryption key / decryption key) to the user or selects from previously input key information to encrypt / decrypt the area designated this time. The key information used for is received (step S13).

  In the area designation information according to the present embodiment, by combining page number information and position information within a page, different encryption target areas can be set for each page of electronic data over a plurality of pages. For this reason, when electronic data covers a plurality of pages, the so-called thumbnail 604 as a page list may be displayed to improve the listability by the user. In the image processing system 900 according to the present embodiment, a definition information setting interface 700 described below can be displayed in a state where a range is selected on the preview screen 600.

  In step S14, a definition information setting interface 700 for adjusting and determining the encryption target area is displayed. The user interface output unit 25 displays the definition information setting interface 700 on the display 108 when a predetermined operation is performed by the user in a state where the area and the encryption key are specified on the preview screen 600 (step S14). ).

  FIG. 7 is a diagram showing a definition information setting interface 700 displayed on the display 108 for setting definition information in the present embodiment. The definition information setting interface 700 is selected by a name input field 701 for inputting a name of definition information for the user to identify the definition information, a selection menu 702 for selecting an encryption mode, and a preview screen 600. Detailed contents of the area are displayed, an area designation information display field 703 for adjusting these contents, a preview field 704 for displaying a preview reduced image, a preview screen display button 705 for returning to the preview screen 600, a setting A save button 706 for saving the contents in the definition information table, an end button 707 for saving the setting contents in the definition information table and ending the pre-definition process are displayed.

  Here, when it is necessary to change the setting contents, for example, to change the area designation information, the user selects the preview screen display button 705 to display the preview screen 600 again to reselect the area, or to display the area designation information display field. The setting content can be changed by a method such as selecting the content displayed in 703 and adjusting the numerical value. When the electronic data defined by the definition information is electronic data over a plurality of pages, the area designation information display field 703 displays information indicating the area to be encrypted in each page. Note that it is possible to designate a plurality of locations in a single page as an encryption target area.

  In step S15, the designated encryption target area and the encryption key are associated with each other and stored in the definition information table (step S15). At this time, the definition information holding unit 22 stores the definition information in the definition information table in association with the unique identification information. The identification information may be automatically generated by the definition information holding unit 22 or may be the name of the definition information designated by the user. The user confirms the setting contents in the definition information setting interface 700, and selects the save button 706 or the end button 707 to complete the pre-definition. Thereafter, the processing shown in this flowchart ends.

  FIG. 8 is a flowchart showing the flow of definition information designation processing in the present embodiment. The definition information specifying process is a process for specifying in advance definition information used for encryption or decryption from a plurality of definition information in the definition information table. Since the definition information is designated in advance by the definition information designation process, the user does not need to select definition information every time the encryption process or the decryption process, or newly set area designation information or key information. Large amounts of electronic data can be continuously encrypted or decrypted. The processing shown in this flowchart is executed in response to an operation that instructs the user to specify definition information. The processing shown in this flowchart is performed by selecting an image processing program from a printer list in a print menu opened in an application that opens some electronic data that can be encrypted, such as a document creation application or a spreadsheet application. Here, the image processing program setting screen (so-called “property”) may be called as a trigger.

  First, the user interface output unit 25 displays a list of definition information defined in the predefinition process (see FIG. 5) on the display 108 (step S21). Here, the list of definition information is displayed in a list format, a pull-down menu format, or the like, and the user can select desired definition information. The user input receiving unit 26 receives an instruction operation for desired definition information selected by the user (step S22). Then, the user-specified content holding unit 24 automatically applies the identification information (see FIG. 4) associated with the definition information related to the accepted instruction operation in the subsequent encryption process or decryption process. (Step S23). Thereafter, the processing shown in this flowchart ends.

  In this embodiment, in this way, definition information is set in advance before encryption processing or decryption processing, and definition information to be actually used is specified, so that when a plurality of electronic data are processed in succession, However, it is not necessary to specify definition information to be applied by the user every time electronic data is input. For this reason, it is possible to remarkably reduce the user's trouble at the time of batch processing for collectively encrypting or decrypting a large amount of fixed form electronic data.

  FIG. 9 is a flowchart showing the flow of encryption processing in the present embodiment. In the processing shown in this flowchart, the user calls a print menu in an application that opens some electronic data that can be encrypted, such as a document creation application or a spreadsheet application, and performs an output instruction by an image processing program. It starts with this.

  In steps S30 and S31, drawing information is received and a digital image is generated. The drawing information input receiving unit 21 receives drawing information input from an external application (step S30), and the digital image generating unit 15 creates bitmap data of a print or display image based on the received drawing information. Thus, a digital image is generated (step S31). Thereafter, the process proceeds to step S32.

  In step S32 and step S33, it is determined whether or not the preview screen 600 is output. If the setting is such that the preview screen 600 is output, the preview screen 600 is output. The user interface output unit 25 determines whether or not to output the preview screen 600 shown in FIG. 6 based on the setting contents set in advance (step S32). In order to make the user confirm the contents of the electronic data to be processed and the encryption target area, a preview screen 600 based on the drawing information acquired in step S31 is generated and displayed on the display 108 (step S33). If it is not set to output the preview screen 600, the process proceeds to step S35.

  In step S34, it is determined whether or not the definition information held in the definition information table is to be used. The definition information acquisition unit 23 reads the definition information from the definition information table and uses it in the subsequent encryption processing by referring to the setting contents related to the image processing program or inquiring of the user, or from the user. It is determined whether to use newly specified area designation and key information. If it is determined that the definition information held in the definition information table is to be used, the process proceeds to step S35. When the area designation and key information newly input from the user are used without using the definition information in the definition information table, the process proceeds to step S36.

  In step S35, definition information used for encryption is read. The definition information acquisition unit 23 reads definition information including area designation information and an encryption key used for encryption from the definition information table. Here, when the identification information indicating the definition information designated in advance in the definition information designation process (see FIG. 8) or the like is held in the user designated content holding unit 24, the definition information acquisition unit 23 Definition information related to identification information is acquired from a definition information table. When the prior designation is not performed, the identification information acquisition unit 18 acquires the identification information included in the digital image by means such as barcode recognition or OCR. Then, the definition information acquisition unit 23 reads definition information related to the identification information acquired by the identification information acquisition unit 18. The identification information can be included in the digital image in the form of a barcode or a character string. Thus, encryption can be performed without the user selecting appropriate definition information based on the contents of the electronic file or paper medium. In the present embodiment, identification information included as an image (an image that can be visually recognized when printed or displayed) in a digital image is acquired by means such as barcode recognition or OCR. The identification information may be included as data that is not normally displayed at the time of drawing (so-called metadata).

  This saves the user from having to specify the definition information, thereby improving work efficiency. In particular, when encrypting documents in a fixed format with multiple patterns, it is very easy to encrypt by including identification information according to the fixed format in the template of the fixed format. Is possible. In addition, it is good also as acquiring identification information and corresponding definition information also in the decoding process mentioned later.

  If the identification information held in the user-specified content holding unit 24 or the identification information included in the digital image cannot be acquired and the definition information used in the encryption process is not yet determined, the definition information A selection screen may be displayed to prompt the user to select definition information (see FIG. 8). Thereafter, the process proceeds to step S38.

  In step S36 and step S37, the input of the encryption target area and the encryption key is accepted. When it is determined in step S34 that the definition information held in the definition information table is not used, the user input receiving unit 26 receives an input of the encryption target area based on the user's mouse operation or the like on the preview screen 600 ( In step S36), an input of an encryption key used for encryption of the input encryption target area is received (step S37). The flow of processing for receiving the input of the encryption target area and the encryption key is substantially the same as the pre-defined processing described with reference to FIG. The encryption target area and the encryption key input here may be stored in the definition information table as definition information. In addition, when saving the encryption target area and the encryption key as definition information, they may be saved automatically, or by a check box for specifying whether or not to save, and a dialog for inquiring whether or not to save the user. It is good also as receiving a user's judgment. Thereafter, the process proceeds to step S38.

  In step S38, encryption is performed. The encryption unit 11 uses the encryption key read in step S35 or the step S37 for the area indicated by the area designation information read in step S35 or the encryption target area input in step S36 of the digital image. The encrypted image is generated by performing the encryption based on the encryption key input in. Details of the encryption processing will be described later. Thereafter, the process proceeds to step S39.

  In step S39, an encrypted image is output. The output unit 12 outputs the electronic file including the encrypted image information generated in step S38 to a storage device such as the HDD 103. The output unit 12 may print (output) the encrypted image on a paper medium using the printer 107. Thereafter, the processing shown in this flowchart ends.

  According to the present embodiment, by encrypting a part of an image based on electronic data, it is possible to permit browsing of other information while restricting browsing of important information. In other words, when working with electronic data that contains some important information such as personal information, only the part containing the personal information is encrypted, and the information necessary for the work is not encrypted. It is possible to perform a work using a document including important information such as information without causing information leakage.

  It should be noted that bar code or OCR readable information may be added to the output encrypted image. Here, the barcode or OCR readable information added to the encrypted image is information including information that can identify the definition information used for the encryption processing. The added information includes, for example, unique identification information (see FIG. 4) for identifying definition information stored in the definition information table. As a result, the user can save the encrypted information without taking the trouble of determining which definition information is used for the encryption process from the contents of the electronic file or the paper medium on which the electronic file is printed. Decoding can be performed.

  FIG. 10 is a flowchart showing the flow of the decoding process in this embodiment. The process shown in this flowchart is started when the user performs an operation to instruct the start of decryption of the electronic file including the information of the encrypted image generated by the process shown in FIG. The

  In step S41, an encrypted image is acquired. The user performs an operation of designating an electronic file including information on the encrypted image generated by the processing shown in FIG. The encrypted image acquisition unit 13 that has received an operation by the user acquires the encrypted image by developing the designated electronic file in the RAM 102. Note that the encrypted image may be acquired not from the electronic file but from a paper medium on which the encrypted image is recorded. In this case, the user performs an operation of giving an acquisition start instruction through the interface of the computer 100 after setting the paper medium on which the encryption information to be decrypted is recorded in the scanner 106. Then, the encrypted image acquisition unit 13 that has received the instruction input controls the scanner 106 to image a paper medium, and converts the imaging result into an encrypted image, thereby acquiring an encrypted image. Thereafter, the process proceeds to step S42.

  In step S42 and step S43, it is determined whether or not to output a preview screen 600b for allowing the user to confirm the content of the encrypted image to be processed and the decryption target area, and the setting is to output the preview screen 600b. In addition, a preview screen 600b is output. Details of the processing are the same as those in step S32 and step S33 shown in FIG. If it is not set to output the preview screen 600b, the process proceeds to step S45.

  FIG. 11 is a diagram showing a preview screen 600b of an encrypted image displayed for specifying a decryption area in the present embodiment. An encrypted image 601b to be decrypted is displayed on the preview screen 600b, and the user can easily designate a region 602b to be decrypted by designating a range using an input device such as the mouse 110. I can do it. A specific method for specifying the area is substantially the same as the method for specifying the encryption target area, and thus the description thereof is omitted.

  In step S44, it is determined whether to use definition information held in the definition information table. The details of the process are substantially the same as in step S34 in the encryption process, and a description thereof will be omitted. If it is determined that the definition information held in the definition information table is to be used, the process proceeds to step S35. When the area designation and key information newly input from the user are used without using the definition information in the definition information table, the process proceeds to step S36.

  In step S45, definition information used for decoding is read. The definition information acquisition unit 23 reads definition information including region designation information and a decryption key used for decryption from the definition information table. As a method for acquiring definition information from the definition information table, there is a method based on the absence of prior designation held in the user-specified content holding unit 24, a method for obtaining identification information included in an encrypted image, and a selection screen. There is a method of displaying and allowing the user to select, and the details of the process are the same as those of the encryption process, and thus the description thereof is omitted. Thereafter, the process proceeds to step S48.

  In step S46 and step S47, input of a decryption target area and a decryption key is accepted. In the preview screen 600b, the user input receiving unit 26 receives an input of a decryption target area based on a user's mouse operation or the like (step S46), and further receives an input of a decryption key used for decryption of the input decryption target area ( Step S47). The flow of processing for receiving the input of the decryption target area and the decryption key is almost the same as the pre-defined processing described with reference to FIG. At this time, the input content may be stored in the definition information table as definition information, as in the encryption process. Thereafter, the process proceeds to step S48.

  However, the decoding target area may be automatically selected. The decryption unit 14 is based on the regularity of the image in the decryption area due to the regular conversion of pixel values during the encryption process, the marker added to identify the position of the decryption area, and the like. It is possible to detect and locate the decryption target area in the encrypted image.

  In step S48 and step S49, decoding is performed and a decoded digital image is output. The decryption unit 14 uses the decryption key read in step S45 or the step S47 for the region indicated by the region designation information read in step S45 or the decryption target region input in step S46 in the encrypted image. The decrypted digital image is generated by decrypting based on the decryption key input in (step S48). Details of the decoding process will be described later. Then, the output unit 12 outputs the electronic file including the digital image information generated in step S48 to a storage device such as the HDD 103 (step S49). Thereafter, the processing shown in this flowchart ends.

  In the process shown in this flowchart, an electronic file including decrypted digital image information is output and the process is terminated. However, by using OCR or the like, input is performed from an application during the encryption process. The electronic data that is the basis of the drawn drawing information or data close to the electronic data may be restored. The electronic data generation unit 501 generates electronic data including the characters in the digital image as character information based on the character code by detecting and specifying the characters in the digital image generated in step S48. By restoring the electronic data before encryption, the decrypted information can be handled as electronic data, and convenience is improved.

  The image processing system according to the present invention may be implemented as an electronic data encryption system or an electronic data decryption system. Hereinafter, an embodiment in which the image processing system is implemented as an electronic data encryption system or an electronic data decryption system will be described. Note that the hardware configuration of the electronic data encryption system or electronic data decryption system in the embodiment described below is substantially the same as the hardware configuration of the image processing system shown in FIG.

<Second Embodiment>
FIG. 12 is a diagram showing an outline of a functional configuration of the electronic data encryption system 200 according to the present embodiment. The electronic data encryption system 200 includes a digital image generation unit 15 that captures a digital image by capturing an image of a paper medium by causing the CPU 101 to execute an electronic data encryption program read from the HDD 103 and expanded in the RAM 102. The encryption unit 11 that generates an encrypted image by encrypting at least a part of the generated digital image, the output unit 12 that outputs the generated encrypted image, and the encryption unit 11 encrypts the digital image. It functions as an area designation information holding unit 16 that holds information for designating an area, and an area designation information acquisition unit 19A that displays options for the user and receives an input of a selection result.

  The digital image generation unit 15 generates a digital image in a pixel format based on electronic data. The digital image generation unit 15 converts an image when the selected electronic data is printed or displayed into a so-called bitmap format digital image. Normally, it consists of character code and format information if it is document data, but the encryption unit 11 encrypts the image by generating an image when the document data is displayed or printed as a bitmap format image. It becomes possible.

  The area designation information holding unit 16 holds area designation information including position information indicating a position on the digital image as area designation information for designating a partial area to be encrypted. The plurality of area designation information is managed in the area designation information table in association with the unique identification information.

  FIG. 13 is a diagram showing the positioning of the electronic data encryption program in the present embodiment. The electronic data encryption program provides a function corresponding to a so-called printer driver for various applications. By mounting the electronic data encryption program on the computer in this way, the user can easily encrypt the printed matter based on the electronic data by the same operation as the normal printing process.

  FIG. 14 is a diagram showing the configuration of the area designation information table in the present embodiment. In the area designation information table, area designation information including position information for indicating an area in the digital image is recorded in association with unique identification information. Since the area designation information is substantially the same as that described in the first embodiment, the description thereof is omitted.

  The position designated by the area designation information as the partial area to be encrypted corresponds to the position where the information to be encrypted is recorded in the electronic data that is the basis of digital image generation. For example, in the document data, when the “important item description column” is the important information to be encrypted, the area where the “important item description column” is arranged in the generated digital image is the region designation information. Specified by. For this reason, the area designation information may be prepared in advance according to the format of the document data as shown in FIG. 14, or may be generated every time encryption is performed according to the contents of the document data. A process for generating the area designation information every time encryption is described in the third embodiment.

  FIG. 15 is a flowchart showing a flow of electronic data encryption in the present embodiment. The processing shown in this flowchart is started when an electronic data encryption program is read from the HDD 103 based on a user operation, loaded in the RAM 102, and executed by the CPU 101.

  In step S101, a digital image is generated. While using a document creation application or the like, the user selects an electronic data encryption program as a print output destination from an application menu and gives an instruction to start printing. The digital image generation unit 15 that has received an instruction input acquires electronic data from an application or the like, and generates a digital image by creating bitmap data of a print or display image. Thereafter, the process proceeds to step S102.

  In step S102, area designation information is designated. The area designation information acquisition unit 19A reads the area designation information candidates from the area designation information holding unit 16, and displays an interface for allowing the user to select based on the read area designation information on the display 108. The area designation information acquisition unit 19A receives an input of user selection and specifies area designation information related to the user selection. Thereafter, the process proceeds to step S103.

  In step S103, encryption is performed. The encryption unit 11 generates an encrypted image by encrypting the area indicated by the area designation information specified in step S102 of the digital image. Details of the encryption processing will be described later. Thereafter, the process proceeds to step S104.

  In step S104, an encrypted image is output. The computer 100 prints (outputs) the encrypted image generated in step S <b> 103 onto a paper medium using the printer 107 when the CPU 101 executes the electronic data encryption program. Thereafter, the processing shown in this flowchart ends.

  FIG. 16 is a diagram showing an outline of a functional configuration of the electronic data decoding system 500 according to the present embodiment. In the electronic data decryption system 500, the CPU 101 executes an electronic data decryption program that is read from the HDD 103 and expanded in the RAM 102, thereby capturing an encrypted image on the paper medium by capturing an image on the paper medium. Unit 13, a decoding unit 14 that generates a decoded digital image by decoding at least a part of the acquired digital image, an electronic data generation unit 501 that generates electronic data based on the decoded digital image, and , Function as.

  The encrypted image acquisition unit 13 acquires information on the paper medium as an encrypted image by imaging the paper medium. In the present embodiment, the computer 100 that executes the scanner 106 and the scanner driver corresponds to the encrypted image acquisition unit 13. However, the encrypted image may be acquired using a device capable of capturing other paper media such as a digital camera.

  FIG. 17 is a flowchart showing the flow of the electronic data decoding process in the present embodiment. The processing shown in this flowchart is started when an electronic data decoding program is read from the HDD 103 based on a user operation, expanded in the RAM 102, and executed by the CPU 101.

  In step S201, an encrypted image is acquired. The user sets a paper medium on which encrypted information to be decrypted is recorded in the scanner 106 and gives an instruction to start acquisition through the interface of the computer 100. The encrypted image acquisition unit 13 that has received an instruction input controls the scanner 106 to image a paper medium, and converts the imaging result into an encrypted image, thereby acquiring an encrypted image. Thereafter, the process proceeds to step S202.

  In step S202, decoding is performed. The decryption unit 14 detects an encrypted area in the encrypted image, and decrypts this area to generate a digital image that has been decrypted. Details of the decoding process will be described later. Thereafter, the process proceeds to step S203.

  In step S203, electronic data is generated. The electronic data generation unit 501 detects electronic characters in the digital image generated in step S202, thereby generating electronic data including the characters in the digital image as character information based on character codes. Thereafter, the processing shown in this flowchart ends.

  Thus, in the decryption process, the encrypted portion is automatically detected, and the detected area is decrypted so that only the user who knows the decryption key can view the information described in the encrypted portion. It is possible to However, it is also possible to display a region information selection interface similar to the encryption process and determine the decryption region according to the region information selected by the user. The decoding accuracy can be improved by adding the automatic detection processing of the decoding area to the area specified by the user. Also, by analyzing the decrypted digital image and restoring the electronic data before encryption, the decrypted information can be handled as electronic data, and convenience is improved.

  According to this embodiment, it is possible to prevent leakage of important information. In addition, by outputting to a paper medium, when a copy is created using a copier or the like, an encrypted image image is deteriorated, and it is impossible to decrypt the image when the copy is repeated. It is possible. Thereby, it is possible to prevent important documents from being easily copied by the copying machine and leaking important information. Furthermore, a special paper medium (so-called copy forgery prevention paper) on which an image such as “copy” appears when a copy is made on a paper medium on which an encrypted image is printed, or such characters appear. By printing the image for the encrypted image at the same time as printing the encrypted image, it is possible to suppress easy copying, or noise may enter the encrypted image due to overlapping of the floating images, so that the image cannot be decrypted Is possible.

  In this embodiment, the encryption system 200 and the decryption system 500 are described as different systems. However, the present invention is an electronic data encryption / decryption system having both encryption and decryption functions. May be implemented. The same applies to the second and fourth embodiments described below.

<Third embodiment>
FIG. 18 is a diagram illustrating an outline of a functional configuration of the electronic data encryption system 200B according to the present embodiment. Similar to the second embodiment, the electronic data encryption system 200B according to the present embodiment includes a digital image generation unit 15, an encryption unit 11, an output unit 12, and an area designation information holding unit 16, and further includes paper. An identification information acquisition unit 18 that acquires identification information recorded on the medium, and an area specification information acquisition unit 19B that acquires related area specification information according to the acquired identification information.

  The identification information acquisition unit 18 acquires identification information included in the electronic data (electronic file) that is the basis of the digital image in order to identify region designation information for encrypting the digital image. The identification information is included in the electronic data as metadata (file header) of the electronic file. FIG. 19 is a diagram illustrating an example of electronic data 800 in which identification information 801 is included in metadata 803 along with information to be encrypted. This identification information 801 is associated with area designation information that designates the partial area 802 of the digital image 804 generated based on the electronic data 800 of the electronic data 800 including the identification information 801 as an area to be encrypted. Yes.

  The area designation information acquisition unit 19B searches the area designation information held in the area designation information holding unit 16 using the identification information acquired by the identification information acquisition unit 18 as a key, and acquires corresponding area designation information. In other words, it takes time and effort for the user to select appropriate area designation information by preliminarily storing, as metadata, identification information of area designation information that designates a portion to be encrypted in the electronic data. The optimum area designation information is automatically selected, and the part to be encrypted can be encrypted.

  FIG. 20 is a flowchart showing a flow of electronic data encryption in the present embodiment. The processing shown in this flowchart is started when an electronic data encryption program is read from the HDD 103 based on a user operation, loaded in the RAM 102, and executed by the CPU 101.

  In step S301, a digital image is generated. Details of the processing are substantially the same as in step S101 described above, and a description thereof will be omitted. Thereafter, the process proceeds to step S302.

  In step S302, identification information is acquired. The identification information acquisition unit 18 acquires identification information from the metadata of the electronic data that is the basis of the digital image acquired in step S301. Thereafter, the process proceeds to step S303.

  In step S303, area designation information is acquired. The area designation information acquisition unit 19B searches the area designation information held in the area designation information holding unit 16 based on the identification information acquired in step S302, and acquires the corresponding area designation information. Thereafter, the process proceeds to step S304.

  Since the processes shown in steps S304 and S305 are substantially the same as the processes shown in steps S103 and S104, the description thereof is omitted.

  By acquiring the identification information and selecting the corresponding area designation information, the user's trouble of designating the area designation information is omitted, and the work efficiency can be improved. In particular, when encrypting documents in a fixed format with multiple patterns, it is very easy to encrypt by including identification information according to the fixed format in the metadata of the template of the fixed format. Is possible.

  As in the second embodiment, in the decryption process, the encrypted part is automatically detected, and the detected area is decrypted, so that the information described in the encrypted part is only for users who know the decryption key. Can be viewed. However, the identification information may be acquired also in the decoding process, and the corresponding decoding area may be determined. Identification information can be obtained from the paper medium by printing a barcode or the like on the printed paper medium and using a technique such as barcode recognition or OCR. Decoding accuracy can be improved by adding the automatic detection processing of the decoding area to the area specified according to the identification information.

<Fourth embodiment>
FIG. 21 is a diagram showing an outline of a functional configuration of the electronic data encryption system 200C according to the present embodiment. As in the second embodiment, the electronic data encryption system 200C according to this embodiment includes a digital image generation unit 15, an encryption unit 11, an output unit 12, and an area designation information holding unit 16, and further includes paper. A keyword detection unit 10 that detects a predetermined keyword from information recorded on the medium, and a region specification information acquisition unit 19C that acquires related region specification information according to a position corresponding to the detected keyword are provided.

  The keyword detection unit 10 reads a character string from the electronic data that is the basis of the digital image generated by the digital image generation unit 15, and compares the read character string with a keyword that is a predetermined character string. Detect keywords in electronic data. Here, the keyword is a character string set for extracting the presence / absence of information to be encrypted from the electronic data and the position of the information to be encrypted when digitalized. FIG. 22 is a diagram showing a display image of electronic data 1100 including a keyword. For example, when “name” and “address” are set as keywords, it is determined whether or not these keywords are included in the electronic data 1100. If they are included, they are converted into digital images. The position information of the position 1101 where the keyword is described is acquired. That is, since it can be estimated that the character string following these keywords is personal information such as name and address, information to be automatically encrypted and area designation information indicating the area 1102 in which this information is described can be obtained. I can do it. In this case, the accuracy of detection can be improved by referring to a name list that covers names generally used for a name and an address list for an address.

  The area designation information acquisition unit 19C according to the present embodiment generates the area designation information for specifying the area corresponding to the keyword detected by the keyword detection unit. Generally, this is area designation information for specifying the area of the character string following the keyword. However, when the character string itself to be encrypted is set as a keyword, information indicating an area in which the keyword detected by the keyword detecting unit is described becomes area specifying information.

  FIG. 23 is a flowchart showing a flow of electronic data encryption in the present embodiment. The processing shown in this flowchart is started when an electronic data encryption program is read from the HDD 103 based on a user operation, loaded in the RAM 102, and executed by the CPU 101.

  In step S401, a digital image is generated. Details of the processing are substantially the same as in step S101 described above, and a description thereof will be omitted. Thereafter, the process proceeds to step S402.

  In step S402, a keyword is detected. The keyword detection unit 10 detects a predetermined keyword by searching the electronic data that is the basis of the digital image generated in step S401. Thereafter, the process proceeds to step S403.

  In step S403, area designation information is acquired. The area designation information acquisition unit 19C generates area designation information for specifying an area corresponding to the keyword according to the keyword position detected in step S402. Specifically, when the keyword is a title of information to be encrypted, area designation information indicating an area in which information following the keyword is described is generated. Further, when the keyword indicates information itself to be encrypted, area designation information indicating an area in which the keyword is described is generated. As the method for designating the region by the region designation information, position information, size information, vector information, and the like are used as in the method described in the second embodiment. Thereafter, the process proceeds to step S404.

  Since the processes shown in steps S404 and S405 are substantially the same as the processes shown in steps S103 and S104, the description thereof is omitted.

  In recent years, the importance of protecting personal information has increased greatly, but important information such as personal information is often described following specific keywords such as “name”, “address”, and “phone number”. According to this embodiment, a keyword is detected from electronic data to be encrypted, and the corresponding part is automatically encrypted, thereby reducing the amount of work when encrypting information described in various formats. It can be reduced.

  As in the second embodiment, in the decryption process, the encrypted part is automatically detected, and the detected area is decrypted, so that the information described in the encrypted part is only for users who know the decryption key. Can be viewed. However, in the decryption process, a keyword may be detected and a corresponding decryption area may be determined. By using the OCR technology, keywords can be detected from printed paper media. Decoding accuracy can be improved by adding the above-described decoding area automatic detection processing to the detected keyword position information.

  In the first to fourth embodiments, a plurality of areas when one electronic data is converted into a digital image may be encrypted with different encryption keys. FIG. 24 is a diagram showing a display image of electronic data 1300 encrypted using a plurality of encryption keys. If there are areas 1301A, 1301B, 1301C, and 1301D, the viewing authority is set for each area by encrypting these areas 1301A, 1301B, 1301C, and 1301D with the corresponding encryption keys 1302A, 1302B, 1302C, and 1302D. It becomes possible to do.

<Encryption unit and decryption unit>
Next, an overview of encryption processing and decryption processing by the encryption unit and the decryption unit in the first to fourth embodiments will be described.

  FIG. 25 is a diagram showing a process outline (part 1) of the encryption process and the decryption process. In FIG. 25, the encryption unit 11 (in the first to third modes, referred to as encryption units 11A, 11B, and 11C, respectively) is based on the input digital image and the encryption key indicating the encryption method. Thus, an encrypted image obtained by encrypting a part of the digital image is output. The printer output unit 12 prints the digital image encrypted by the encryption unit 11 on a printable physical medium such as paper. The scanner (camera) reading unit 13 reads the print image output from the printer output unit 12 using a scanner or a camera.

  Then, the decryption unit 14 (in the first to third aspects, referred to as decryption units 14A, 14B, and 14C, respectively) decrypts the print image output by the printer output unit 12 and the input decryption key. Get. Only when the input decryption key is correct, the encrypted image can be properly decrypted, and the information hidden by the encryption by the encryption unit 11 can be viewed.

  FIG. 26 is a diagram illustrating a process outline (part 2) of the encryption process and the decryption process. As shown in FIG. 26, the encryption process and the decryption process in the first to third aspects to which the present invention is applied perform the digital image encrypted by the encryption unit 11 without using a printer or a scanner. It is also possible to input the electronic document image as it is to the decoding unit 14 to obtain a decoded image.

  Next, first to third aspects to which the present invention is applied will be described. First, the 1st aspect to which this invention is applied is demonstrated.

  FIG. 27 is a diagram showing an outline of the encryption processing in the first mode. In FIG. 27, the encryption unit 11A includes an encryption area determination unit 31, an image conversion unit 32, a pixel value conversion unit 33, and a marker addition unit 34.

  The encryption area designating unit 31 selects an area to be encrypted from the input image including the area to be encrypted.

  FIG. 28 is a diagram illustrating an example of selecting an encryption area. That is, as shown in FIG. 28A, the encryption area designating unit 31 selects the area 42 to be encrypted from the digital image (input image) 41 including the area to be encrypted. This area 42 is converted into a converted image 43 as shown in FIG. 28B by the processing of the image conversion unit 32 and the pixel value conversion unit 33 described later, and the digital image 41 is an encrypted image including the converted image 43. 44.

  Returning to the description of FIG. When the area 42 to be encrypted is selected by the encryption area designating unit 31, the area 42 to be encrypted and the encryption key are input in the image conversion unit 32, and the image of the area 42 to be encrypted by the conversion method corresponding to the encryption key Is visually transformed. The conversion parameter at that time is created from binary data obtained from the input encryption key.

  FIG. 29 is a diagram illustrating an input example of the encryption key. The example shown in FIG. 29 is an example of an encryption key and binary data generated by the encryption key. For example, a numerical value “1234” as an encryption key is input as binary data “100011010010”, and a character string “ango” as an encryption key is input as binary data “01100001011011100110011101101111”.

  As the image conversion method, in the first aspect, there are two methods: a conversion method by dividing the image into minute regions and rearranging the minute regions (referred to as scramble processing) and a conversion method by compressing the image. Show.

  First, the scramble process will be described. In the scramble process, first, the image of the selected area 42 is divided into small areas of a certain size, and then the small areas are rearranged by binary data obtained from the encryption key.

  FIG. 30 is a diagram illustrating an example of the scramble process in the image conversion unit. As shown in FIG. 30A, first, the area 42 selected by the encryption area designating unit 31 is divided in the vertical direction, and each bit of the binary string of the encryption key 61 is used as the boundary of the divided area 42. Corresponding in order from the left, when the bit is “1”, adjacent divided columns are exchanged, and when the bit is “0”, nothing is performed in order from the left. When the number of bits in the binary string is insufficient with respect to the number of division boundaries, the same binary string is repeated from the position where the binary string is insufficient, and the exchange processing is performed up to the right end of the region 42.

  Subsequently, as shown in FIG. 30B, the image area 62 subjected to the exchange process is divided in the horizontal direction, and each bit of the binary string of the encryption key 61 is moved up to the boundary of the divided image area 62. The same exchange processing as that performed in the vertical division is performed in order from the top in line units.

  Then, as shown in FIG. 30C, as a result of performing the exchange process on each divided image, a scrambled image 63 which is a processed image obtained by scrambled the original area 42 is obtained.

  As an expansion method of this scramble processing example, the horizontal direction and the vertical direction can be performed twice or more, and the size of the divided area can be changed in the second and subsequent replacements. Furthermore, another binary string can be used for exchanging the divided areas in the horizontal direction and the vertical direction. These extension methods are particularly effective as means for preventing the same processed image from being generated from different encryption keys when the size of the input image is small and the bit length of the encryption key is long.

  FIG. 31 is a diagram illustrating another example of the scramble process in the image conversion unit. As another scramble processing method different from the scramble processing described with reference to FIG. 30, a method of exchanging pixels in units of minute regions as shown in FIG. 31 is also possible. That is, the input image is divided into rectangular minute areas, and the divided minute areas are exchanged. As a result, the number of scrambles is increased and the encryption strength can be increased as compared with the above-described method using the exchange between the horizontal direction and the vertical direction (row and column).

  FIG. 32 is a diagram showing a modification of the shape of the minute area in the scramble process. Further, as the shape of the minute area in the scramble processing, for example, a triangle as shown in FIG. 32A can be used in addition to the quadrangle shown in FIG. Further, as shown in FIG. 32B, minute regions having different shapes and sizes can coexist.

  Next, a conversion method by compressing an image will be described.

  FIG. 33 is a diagram illustrating compression processing in the image conversion unit. When the input image 41 is a binary image, first, the image in the area 42 selected by the encryption area designating unit 31 is compressed as shown in FIG. 33A, and the input image 41 is shown in FIG. A binary string 71 is created. The compression method here includes all types of compression, such as run-length compression used for binary image data transfer in a facsimile machine, and JBIG (Joint Bi-level Image experts Group) compression, which is a standard compression method for binary images. The method is applicable.

  FIG. 34 is a diagram showing a process for imaging the converted data. Subsequent to the compression of the area 42 as shown in FIG. 33, each bit of the binary string 71 which is the converted compressed data is converted into “white” if the bit is “0” as shown in FIG. If the bit is “1”, the rectangular image (processed image) 81 is created by enlarging the rectangle to a specified size of “black”, and arranged as a monochrome rectangular image 81 in the area 42 of the image to be encrypted.

  When it is desired to arrange the converted compressed data (binary string 71) so as to fit within the image of the selected area 42, the size of the rectangular image 81 depends on the compression ratio of the selected area 42. For example, if the compression ratio is 1/4 or less, the size of the square image 81 is 2 × 2 pixels at most, and if it is 1/16 or less, the size is 4 × 4 pixels.

  On the other hand, when the size of the square image 81 is designated in advance and it is desired to store the compressed data in the image of the selected area 42, it is necessary to achieve a compression ratio depending on the size of the square image 81 in the first image compression processing. There is. For example, when the square is 4 × 4 pixels in size, a compression ratio of 1/16 or more is required. In this case, a method in which information in the selected area 42 is dropped in advance and a method using an irreversible compression method are effective.

  With the encryption processing for enlarging and compressing the compressed data, for example, the enlarged monochrome block can be recognized even when the encrypted image is read with a low-resolution camera, so that the encrypted image can be correctly decrypted.

  Returning to the description of FIG. The pixel value conversion unit 33 converts the pixels in the processed image 63 converted by the image conversion unit 32 at regular intervals so that the converted image 43 forms a substantially grid-like striped pattern.

  FIG. 35 is a diagram illustrating an example (part 1) of the pixel value conversion processing in the pixel value conversion unit. In the pixel value conversion unit 33, the pixels of the processed image 63 in which the area 42 is scrambled by the image conversion unit 32 are converted at regular intervals so that the encrypted image 44 forms a generally grid-like striped pattern as a whole. . For example, as shown in FIG. 35, conversion is performed such that the scrambled image 63 shown in FIG. 35A is inverted at the colored portion of the checkered pattern (checkered pattern) image 91 shown in FIG. As a result, as shown in (C), the converted image 92 in which the encrypted image 44 as a whole forms a substantially grid-like striped pattern is obtained. Thereby, the generated striped pattern is used to detect the detailed position of each pixel in the encryption area when the encrypted image 44 is decrypted.

  It is also possible to carry out another conversion for these series of processes. For example, the process of inverting the pixel value may be a process of adding a specified value.

  Also, the checkered pattern image 91 shown in FIG. 35B is approximately the same size as the scrambled image 63 shown in FIG. 35A, but by using a size smaller than the scrambled image 63, the periphery of the scrambled image 63 is displayed. Only the center part other than the above may be reversed.

  FIG. 36 is a diagram illustrating an example (part 2) of the pixel value conversion processing in the pixel value conversion unit. Further, various shapes can be applied to the region 42 where the pixel value is converted as shown in FIGS. Since the pixel value conversion is a process aimed at detecting the boundary position between the small regions with high accuracy, it is also conceivable to convert the pixel value only at the boundary part as shown in FIG. Also, by performing pixel value conversion while shifting little by little with respect to the minute area as shown in FIG. 36B, the boundary between conversion and non-conversion appears at finer intervals. The pixel position can be detected in more detail. In addition, if pixel value conversion is performed only on a portion where the boundaries of minute regions intersect as shown in FIG. 36C, image quality degradation when reading and decoding an image printed on paper or the like with a scanner or camera is minimized. Can be suppressed.

  Here, when the shape of the minute region is not a square having a uniform size, as shown in FIG. 32, a triangle (FIG. 32A) and different sizes and shapes coexist (FIG. 32B). ) Is not limited to the above-described conversion example, it is added that it is necessary to perform pixel value conversion by a method according to the shape.

  As described above, in the present invention, the regular pattern representing the encrypted position is not generated by overwriting the input image as in Patent Document 1, but is generated by converting the pixel value of the input image. is doing. Therefore, unlike the prior art, the image information at the end of the encrypted image is not sacrificed for position detection, and the original image information can be efficiently encrypted in the form of coexisting position detection information. The

  Note that if some image information is included in the portion constituting the pattern, the regularity is somewhat lost. However, as described in the process of the decryption unit 14 described later, the statistical properties of the entire encrypted image are used to encrypt the image. The position can be detected.

  Returning to the description of FIG. The marker adding unit 34 adds the positioning markers to, for example, three places other than the lower right among the four corners of the converted image 92 converted by the pixel value converting unit 33 to create the encrypted image 44.

  The marker adding unit 34 arranges positioning markers for specifying the position of the encrypted area 42 at, for example, three positions other than the lower right among the four corners of the converted image 92.

  FIG. 37 is a diagram illustrating an example of a positioning marker used in the encryption process. The positioning marker used in the first mode is assumed to have a round cross shape as shown in FIG. If the shape of the positioning marker is more broadly described, it may be constituted by a solid circle or polygon and a plurality of lines intersecting with the circumference. As an example of this, three lines from the center toward the circumference like those in the shape of a Chinese character “field” like the positioning marker in FIG. 37B or the positioning marker in FIG. Examples include those that appear in a radial pattern, and those in which the line is cut halfway like the positioning marker of (D).

  In addition, the color configuration of the positioning marker may be the simplest as long as the background is white and the foreground is black, but is not limited thereto, and may be appropriately changed according to the color (pixel value) distribution of the converted image 92. Absent. In addition, instead of designating a predetermined color for the background and the foreground, a method of forming a positioning marker by inverting the foreground pixel values while the background color remains the digital image 41 may be considered. In this way, it is possible to encrypt the image while retaining the input image information of the positioning marker portion.

  FIG. 38 is a diagram illustrating an example of an encrypted image. The encrypted image 44 as shown in FIG. 38 is finally generated by the above processing of the encryption unit 11A. The encrypted image 44 includes a converted image 92 and a positioning marker 121.

  Furthermore, in the encryption method according to the first aspect, when “processing for rearranging minute regions (scramble processing)” is used in the image conversion unit 32, not only binary images but also grayscale or color images are used. Even encryption processing can be applied.

  FIG. 39 shows an example in which a grayscale image is encrypted. In FIG. 39, the grayscale image 131 shown in (A) generates an encrypted image 132 including a converted image 133 and a positioning marker 134 as shown in (B) by the processing of the encryption unit 11A.

  Next, the decoding unit 14A will be described.

  FIG. 40 is a diagram showing an outline of the decoding process in the first mode. In FIG. 40, the decryption unit 14A includes a marker detection unit 141, an encryption area detection unit 142, an encryption position detection unit 143, and an image reverse conversion unit 144.

  The marker detection unit 141 detects the position of the positioning marker added by the marker adding unit 34 from the encrypted image using a general image recognition technique. As a detection method, pattern matching, analysis on graphic connectivity, or the like can be applied.

  The encryption area detection unit 142 detects the area of the encrypted image based on the positional relationship between the three positioning markers detected by the marker detection unit 141.

  FIG. 41 is a diagram illustrating a process of detecting an encryption area from a positioning marker. As shown in FIG. 41A, when at least three positioning markers 152 are detected from the encrypted image 151 by the marker detection unit 141, as shown in FIG. 41B, one encryption area 153 is stored. Can be detected. That is, since the three positioning markers 152 are arranged at the four corners of the rectangular encryption area 153, the figure obtained by connecting these three points (positions of the positioning markers 152) with lines is approximately a right triangle. Therefore, when three or more positioning markers 152 are detected, the positional relationship of the three positioning markers 152 includes an area configured in a shape close to a right triangle, and the positions of the three positioning markers 152 are set to four corner portions. A rectangle having three corners is defined as an encryption area 153. If the number of detected positioning markers 152 is two or less, the corresponding encrypted area 153 cannot be specified, and therefore the decryption process is terminated because there is no encrypted image.

  FIG. 42 is a flowchart showing the flow of the encrypted area detection process. In the encryption area detection process executed by the encryption area detection unit 142, first, in step S1601, the number of positioning markers 152 detected by the marker detection unit 141 is substituted into a variable n, and in step S1602, the encryption area detection process is performed. 0 is substituted into the detection flag reg_detect 153.

  In step S1603, it is determined whether or not the variable n to which the number of positioning markers 152 is assigned is 3 or more. If the variable n is not 3 or more, that is, if the variable n is 2 or less (step S1603). : No), the decryption process including the present encrypted area detection process is terminated.

  On the other hand, if the variable n is 3 or more (step S1603: Yes), in step S1604, three positioning markers 152 among the positioning markers 152 detected by the marker detection unit 141 are selected, and the selection is performed in step S1605. It is determined whether or not the positional relationship between the three positioning markers 152 is a substantially right triangle.

  If the positional relationship between the three selected positioning markers 152 is not a substantially right triangle (step S1605: No), whether or not all three combinations of the positioning markers 152 detected by the marker detection unit 141 have been completed in step S1606. If not completed (step S1606: No), the process returns to step S1604 to select the other three points, and if completed (step S1606: Yes), the process proceeds to step S1608.

  On the other hand, if the positional relationship between the three selected positioning markers 152 is a substantially right triangle (step S1605: Yes), 1 is substituted into the detection flag reg_detect in step S1607.

  In step S1608, it is determined whether 1 is assigned to the detection flag reg_detect, that is, whether or not the three positioning markers 152 whose three-point positional relationship is a right triangle can be detected, and reg_detect is set. If 1 is assigned (step S1608: Yes), the process proceeds to the process of the encrypted position detection unit 143. If 1 is not assigned to reg_detect (step S1608: No), decryption including the encryption area detection process is performed. The process ends.

  Returning to the description of FIG. The encrypted position detecting unit 143 uses the fact that the end portion of the encrypted area 153 detected by the encrypted area detecting unit 142 forms a regular pixel distribution in order to correctly decrypt the encrypted image 151. Then, the detailed position of each pixel in the encryption area 153 is detected by frequency analysis or pattern matching. This detection uses the property that the entire encrypted image 151 forms a periodic pattern by the pixel value conversion (inversion) processing of the pixel value conversion unit 33.

  As one detection method, first, the period (width) of the pattern is obtained by a frequency analysis method such as Fast Fourier Transform (FFT) in the horizontal and vertical directions of the image, and then the boundary position (offset) by template matching or the like. ) Can be considered.

  In addition, it is possible to detect the boundary position by Hough transform by using the property that the boundary portion becomes linear when an edge detection filter (Laplacian filter or the like) is applied to the encrypted image.

  FIG. 43 is a diagram illustrating an example in which the encrypted position is detected. When the encrypted digital image 41 is complicated, there is a possibility that a portion where the periodicity of the encrypted image 44 is significantly impaired appears. In such a case, it is effective to perform the encryption position detection by limiting the image area used for the calculation of the pattern period and the boundary position to a portion having a relatively strong periodicity.

  Returning to the description of FIG. The image reverse conversion unit 144 uses the encrypted position information detected by the encrypted position detection unit 143 and the decryption key input by the user to convert the encrypted image 44 into the image conversion unit 32 by a method corresponding to the decryption key. The inverse conversion process of the conversion process by is executed to generate a decoded image. The decryption processing procedure is realized by the reverse procedure of the encryption processing, and thus the description thereof is omitted. The above is the description of the first aspect to which the present invention is applied.

  Next, a second mode to which the present invention is applied will be described.

  FIG. 44 is a diagram showing an overall image of the second mode. In the second mode, a specific check mark 182 for verifying the validity of the decryption of the encrypted image 183 is added to an arbitrary place in the area 181 to be encrypted before the encryption process (see FIG. 44 (A)) encryption is performed ((B) in FIG. 44), and if the check mark 182 added in advance after decrypting the encrypted image 183 is detected from the decrypted image 184, it is decrypted as correctly decrypted. The process ends ((C) in FIG. 44). When the check mark 182 is not detected ((D) in FIG. 44), the encryption position is corrected, and the decryption process is repeated until the check mark 182 is detected or until a specified criterion is satisfied.

  FIG. 45 is a diagram showing an outline of the encryption processing in the second mode. 45, the encryption unit 11B includes an encryption area determination unit 31, a check mark addition unit 192, an image conversion unit 32, and a pixel value conversion unit 33.

  As in the first mode, the encryption area designating unit 31 selects an area to be encrypted from the input image including the area to be encrypted.

  Then, the check mark adding unit 192 adds a specific check mark 182 for verifying the validity of the decryption of the encrypted image 183 to any place in the area 181 to be encrypted. It is desirable to add the check mark 182 to a flat region having a pixel distribution with as little image information as possible.

  After adding the check mark 182 to the designated position, the area 181 to be encrypted and the encryption key are input in the image conversion unit 32 and the area 181 to be encrypted by the conversion method corresponding to the encryption key, as in the first mode. The image is visually converted, and the pixel value conversion unit 33 converts the pixels in the processed image converted by the image conversion unit 32 at regular intervals so that the converted image forms a substantially grid-like striped pattern. To.

  FIG. 46 is a diagram showing an outline of the decoding process in the second mode. 46, the decryption unit 14B includes an encryption area detection unit 201, an encryption position detection unit 143, an image reverse conversion unit 144, a check mark detection unit 204, and an encryption position correction unit 205.

  First, the encrypted area detection unit 201 detects a rough area of the encrypted image 183. Since the pixel distribution of the encrypted image 183 is approximately checkered by the encryption processing of the encryption unit 11B, performing frequency analysis such as FFT in the horizontal direction and the vertical direction respectively corresponds to the fringe period. The power of the frequency becomes remarkably strong.

  FIG. 47 is a diagram for explaining an encryption area detection method. As shown in FIG. 47A, when the encrypted image 211 is subjected to frequency analysis, as shown in FIG. 47B, a region where the power of a certain frequency (a frequency that is an integer multiple of the frequency) protrudes is expressed as “periodicity”. It is expressed as “strong” 214. Since the periodicity of the pixel distribution tends to be strong in the encryption area, it is possible to detect the approximate encryption area and period of the striped pattern.

  Returning to the description of FIG. The encryption position detection unit 143 identifies a rough area for encryption by the encryption area detection unit 201, and then more accurately detects the encryption area, and at the same time, detects the detailed position of each pixel in the encryption area. To do. As an example of position detection, first, a boundary position (offset) of pixel value conversion is obtained from the period of the striped pattern obtained by the encryption area detection unit 201 and the distribution of pixel absolute value difference, and the pixel absolute value difference is further relative from there. A method of narrowing a large area can be considered. In addition, as with the encrypted position detection unit 143 of the first aspect, it is possible to use Hough transform for detecting the encrypted position.

  FIG. 48 is a diagram for explaining a method of detecting an encryption position (horizontal direction). When the encryption area detection process as described above is performed in the horizontal and vertical directions, the encrypted position 221 is detected as shown in FIG.

  Returning to the description of FIG. The image inverse transform unit 144 performs the same method as the first mode using the encrypted position information and the decryption key, and generates a decrypted image.

  The check mark detection unit 204 attempts to detect a check mark from the decoded image decoded by the image inverse conversion unit 144. Since the detection method is the same as the marker detection process in the first aspect, the description is omitted. If a check mark is detected, a decoded image is output and the process is completed. If the check mark is not detected, the encryption position correction unit 205 corrects the encrypted position, and repeats the decryption process (image reverse conversion process) until the check mark is detected or until the specified standard is satisfied.

  FIG. 49 is a diagram illustrating an example in which the detection of the encrypted position is incorrect. As shown in FIG. 49, a case where the end of the encrypted image is overlooked (missing line 231) can be considered. Therefore, when the detection of the check mark 221 fails, the lines indicating the encryption position are added or deleted at the left and right ends and the upper and lower ends, and image reverse conversion processing is performed to determine whether the check mark 221 can be detected. consider. If the check mark 221 cannot be detected no matter how the line is added or deleted, the process ends without outputting the decoded image. The above is the description of the second aspect to which the present invention is applied.

  Next, a third mode to which the present invention is applied will be described. In the third embodiment of the present invention, an image using both the positioning marker for specifying the encryption area shown in the first mode and the check mark for determining the validity of the decrypted image of the second mode. Encrypt / decrypt. By using these two types of positioning markers for position detection and check marks for confirming the decrypted image, it is possible to reduce image decryption errors when a correct decryption key is input.

  FIG. 50 is a diagram showing an outline of the encryption processing in the third mode. 50, the encryption unit 11C includes an encryption area determination unit 31, a check mark addition unit 192, an image conversion unit 32, a pixel value conversion unit 33, and a marker addition unit 34.

  First, an image area to be encrypted is selected by the encryption area specifying unit 31, and a check mark for decryption verification is added by the check mark adding unit 192 in the same manner as in the second mode. After adding the check mark, the image conversion unit 32 and the pixel value conversion unit 33 perform image processing in the same manner as in the first aspect 1 and 2 to encrypt the image, and the marker addition unit 34 detects the encrypted area. A positioning marker is added in the same manner as in the first embodiment. Since the contents of these processes are the same as those in the first aspect or the second aspect, description thereof is omitted.

  FIG. 51 is a diagram showing an outline of the decoding process in the third mode. In FIG. 51, the decryption unit 14C includes a marker detection unit 141, an encryption area detection unit 142, an encryption position detection unit 143, an image reverse conversion unit 144, a check mark detection unit 204, and an encryption position correction unit 205. Yes.

  First, the marker detection unit 141 detects a positioning marker by the same method as in the first mode, and the subsequent encryption region detection unit 142 detects the encryption region by the same method as in the first mode. Further, the encrypted position detection unit 143 detects the detailed position of each pixel in the encryption area by the same method as in the first mode. In addition, the processing procedures executed by the image reverse conversion unit 144, the check mark detection unit 204, and the encrypted position correction unit 205 are the same as those in the second mode, and thus description thereof is omitted. The above is the description of the third aspect to which the present invention is applied.

Claims (25)

Drawing information input receiving means for receiving input of drawing information for drawing the contents of electronic data;
Digital image generating means for generating a digital image as a set of pixels based on drawing information received by the drawing information input receiving means;
Definition information including area designation information for specifying a partial area to be encrypted in the digital image generated by the digital image generation means, and key information used for encrypting the partial area. Definition information acquisition means to acquire;
An encryption means for generating an encrypted image obtained by encrypting the image of the partial area by converting the image of the partial area specified based on the area specifying information based on the key information;
Output means for outputting the encrypted image corresponding to the content of the electronic data generated by the encryption means;
An image processing system comprising: The encryption unit converts the image of the partial area into a processed image based on key information, and regularly converts the pixel value of the processed image to be used for specifying an encryption position at the time of decryption. Generating the encrypted image, including a converted image having regularity to be
The image processing system according to claim 1. Encrypted image acquisition means for acquiring an encrypted image generated by converting at least a part of a digital image as a set of pixels based on an encryption key;
Definition information obtaining means for obtaining definition information including region designation information for specifying a decryption region to be decrypted in the encrypted image, and a decryption key used when decrypting the partial region;
Decoding means for generating a digital image obtained by decoding the image of the decoding area by converting the image of the decoding area specified based on the area specifying information based on the decoding key;
Output means for outputting the digital image generated by the decoding means;
An image processing system comprising: The decryption means detects an encrypted position where pixel values are regularly converted in the decryption area, and decrypts the decryption area into a digital image based on the encrypted position and a decryption key.
The image processing system according to claim 3. A definition information holding unit that holds a plurality of the definition information defined in advance in association with identification information for identifying the definition information;
The definition information acquisition unit is configured to generate an encrypted image by the encryption unit or a digital image by the decryption unit from the plurality of definition information held by the definition information holding unit based on the identification information. Obtaining the definition information including the area designation information and the key information used;
The image processing system according to any one of claims 1 to 4. Of the plurality of definition information held by the definition information holding means, further comprising user-specified content holding means for holding identification information related to the definition information designated in advance by the user,
The definition information acquisition means acquires the definition information related to the identification information held by the user-specified content holding means from a plurality of the definition information held by the definition information holding means.
The image processing system according to claim 5. An identification information acquisition unit that acquires the identification information from the digital image generated by the digital image generation unit or the encrypted image acquired by the encrypted image acquisition unit;
The definition information acquisition means acquires the definition information related to the identification information acquired by the identification information acquisition means from a plurality of the definition information held by the definition information holding means.
The image processing system according to claim 5 or 6. The identification information acquisition means acquires the identification information by detecting at least one of characters, symbols, patterns, and colors included in the digital image or the encrypted image from the image.
The image processing system according to claim 7. Computer
Drawing information input receiving means for receiving input of drawing information for drawing the contents of electronic data;
Digital image generating means for generating a digital image as a set of pixels based on drawing information received by the drawing information input receiving means;
Definition information including area designation information for specifying a partial area to be encrypted in the digital image generated by the digital image generation means, and key information used for encrypting the partial area. Definition information acquisition means to acquire;
An encryption means for generating an encrypted image obtained by encrypting the image of the partial area by converting the image of the partial area specified based on the area specifying information based on the key information;
Output means for outputting the encrypted image corresponding to the content of the electronic data generated by the encryption means;
An image processing program that functions as Computer
Encrypted image acquisition means for acquiring an encrypted image generated by converting at least a part of a digital image as a set of pixels based on an encryption key;
Definition information obtaining means for obtaining definition information including region designation information for specifying a decryption region to be decrypted in the encrypted image, and a decryption key used when decrypting the partial region;
Decoding means for generating a digital image obtained by decoding the image of the decoding area by converting the image of the decoding area specified based on the area specifying information based on the decoding key;
Output means for outputting the digital image generated by the decoding means;
An image processing program that functions as Computer
A plurality of definition information defined in advance, further functioning as definition information holding means for holding in association with identification information for identifying the definition information;
The definition information acquisition unit is configured to generate an encrypted image by the encryption unit or a digital image by the decryption unit from the plurality of definition information held by the definition information holding unit based on the identification information. Obtaining the definition information including the area designation information and the key information used;
The image processing program according to claim 9 or 10. By computer system
A drawing information input receiving step for receiving drawing information input for drawing the contents of electronic data;
A digital image generating step for generating a digital image as a set of pixels based on the drawing information received in the drawing information input receiving step;
Definition information including area designation information for specifying a partial area to be encrypted in the digital image generated in the digital image generation step, and key information used for encrypting the partial area. A definition information acquisition step to be acquired;
An encryption step of generating an encrypted image in which the image of the partial area is encrypted by converting the image of the partial area specified based on the area specifying information based on the key information;
An output step of outputting the encrypted image corresponding to the content of the electronic data generated in the encryption step;
Is an image processing method. By computer system
An encrypted image acquisition step of acquiring an encrypted image generated by converting at least a part of a digital image as a set of pixels based on an encryption key;
A definition information acquisition step for acquiring definition information including region designation information for specifying a decryption region to be decrypted in the encrypted image, and a decryption key used when decrypting the partial region;
A decoding step of generating a digital image obtained by decoding the image of the decoding area by converting the image of the decoding area specified based on the area specifying information based on the decoding key;
An output step of outputting the digital image generated in the decoding step;
Is an electronic data decoding method. By computer system
A definition information holding step for holding a plurality of the definition information defined in advance in association with identification information for identifying the definition information is further executed,
In the definition information acquisition step, based on the identification information, from the plurality of definition information held by the definition information holding step, to generate an encrypted image in the encryption step or to generate a digital image in the decryption step The definition information including the area designation information and the key information to be used is acquired.
The image processing method according to claim 12 or 13. Digital image generating means for generating a digital image as a set of pixels based on electronic data;
An encryption area specifying means for specifying a partial area to be encrypted in the digital image generated by the digital image generating means;
Image conversion means for converting the image of the partial area into a processed image based on an encryption key;
Pixel value conversion means for generating a converted image having regularity used for specifying the position of the partial region at the time of decoding by regularly converting the pixel value of the processed image;
Output means for outputting an encrypted image including the converted image;
With
The encryption area designating unit designates an area indicated by area designation information for identifying an area on the digital image as a partial area to be encrypted.
Electronic data encryption system. Based on information included in the electronic data, further comprising region designation information obtaining means for obtaining the region designation information.
The electronic data encryption system according to claim 15. An area designation information holding means for holding the area designation information in association with identification information for identifying the area designation information;
The area designation information acquisition means acquires the area designation information associated with the input identification information among the area designation information held by the area designation information holding means.
The electronic data encryption system according to claim 16. Further comprising identification information acquisition means for acquiring the identification information included in the electronic data;
The region designation information acquisition unit acquires the region designation information associated with the identification information acquired by the identification information acquisition unit among the region designation information held by the region designation information holding unit.
The electronic data encryption system according to claim 17. A keyword detection unit for detecting the keyword included in the electronic data by comparing a character string in the electronic data with a keyword that is a predetermined character string;
The area designation information acquisition means acquires the area designation information by generating the area designation information for specifying an area corresponding to the keyword detected by the keyword detection means,
The electronic data encryption system according to claim 16. The area designation information acquisition means acquires the area designation information for designating a first partial area and a second partial area to be encrypted,
The image conversion means converts the first partial area and the second partial area into processed images based on different encryption keys, respectively.
The electronic data encryption system according to any one of claims 16 to 19. An encrypted image acquisition means for acquiring an encrypted image recorded on the paper medium by imaging the paper medium;
Decryption area designating means for designating an encrypted area in the encrypted image obtained by the encrypted image obtaining means as a decryption area to be decrypted;
Encrypted position detecting means for detecting an encrypted position in which pixel values are regularly converted in the decryption area;
Decryption means for decrypting the decryption area into a digital image based on the encrypted position and a decryption key;
Electronic data generating means for detecting and identifying characters in the digital image decoded by the decoding means, and generating electronic data including the characters in the digital image as character information by a character code;
With
The decryption area designating unit designates an area indicated by area designation information for identifying an area on the encrypted image as a decryption area.
Electronic data decoding system. Computer
Digital image generating means for generating a digital image as a set of pixels based on electronic data;
An encryption area specifying means for specifying a partial area to be encrypted in the digital image generated by the digital image generating means;
Image conversion means for converting the image of the partial area into a processed image based on an encryption key;
Pixel value conversion means for generating a converted image having regularity used for specifying the position of the partial region at the time of decoding by regularly converting the pixel value of the processed image;
Output means for outputting an encrypted image including the converted image;
Function as
The encryption area designating unit designates an area indicated by area designation information for identifying an area on the digital image as a partial area to be encrypted.
Electronic data encryption program. A computer to which a paper medium imaging device is connected;
An encrypted image acquisition means for acquiring an encrypted image recorded on the paper medium by imaging the paper medium;
Decryption area designating means for designating an encrypted area in the encrypted image obtained by the encrypted image obtaining means as a decryption area to be decrypted;
Encrypted position detecting means for detecting an encrypted position in which pixel values are regularly converted in the decryption area;
Decryption means for decrypting the decryption area into a digital image based on the encrypted position and a decryption key;
Electronic data generating means for detecting and identifying characters in the digital image decoded by the decoding means, and generating electronic data including the characters in the digital image as character information by a character code;
Function as
The decryption area designating unit designates an area indicated by area designation information for identifying an area on the encrypted image as a decryption area.
Electronic data decryption program. By computer system
A digital image generating step for generating a digital image as a set of pixels based on electronic data;
An encryption area specifying step for specifying a partial area to be encrypted in the digital image generated in the digital image generation step;
An image conversion step of converting the image of the partial area into a processed image based on an encryption key;
A pixel value conversion step for generating a converted image having regularity used for specifying the position of the partial region at the time of decoding by regularly converting the pixel values of the processed image;
An output step of outputting an encrypted image including the converted image;
Is executed,
In the encryption area designation step, an area indicated by area designation information for identifying an area on the digital image is designated as a partial area to be encrypted.
Electronic data encryption method. By a computer system having a paper medium imaging device,
An encrypted image acquisition step of acquiring an encrypted image recorded on the paper medium by imaging the paper medium;
A decryption area designating step of designating an encrypted area in the encrypted image obtained in the encrypted image obtaining step as a decryption area to be decrypted;
An encrypted position detecting step for detecting an encrypted position in which pixel values are regularly converted in the decryption area; and
A decryption step of decrypting the decryption area into a digital image based on the encrypted position and a decryption key;
An electronic data generation step of detecting and specifying characters in the digital image decoded in the decoding step, and generating electronic data including the characters in the digital image as character information by a character code;
Is executed,
In the decryption area designation step, an area indicated by area designation information for specifying an area on the encrypted image is designated as a decryption area.
Electronic data decoding method.

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