JP2008028449A - Confidential document processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable disclosure or copy of confidential information for each region of documents in accordance with the authority level of each user handling the documents. <P>SOLUTION: A document printer 20 forms confidential level setting information 22 for setting a plurality of confidential levels for each of types of operations on the basis of a user's setting operation for each image region of an original document 6, embeds the setting information 22 as a watermark image, and prints a confidential level-embedded document 3. A document copy reader 30 reads the setting information 22 embedded in the watermark information from the read data of the document 3, collates an authority level 443 acquired form user management information 41 based on inputted user information with the setting information 22, and determines a region where copy can be made or a region where an encrypted image can be decrypted into an original image. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a secret document processing device, and relates to a copy operation for a document and a decryption operation for an encrypted document. Information in which a plurality of secret levels are set for each operation type and area is stored by electronic watermarking. Can be copied or decrypted based on the authority level of the user who performs the copy operation or decryption operation on the printed document embedded in the image and the secret level read from the watermark image embedded in the document The present invention relates to a technique for determining and processing an image area.

  In order to ensure information security, a system that embeds secret information in a document based on an encryption key and extracts the embedded secret information is disclosed in Japanese Patent Application Laid-Open Publication No. 2003-122867 “Secret information processing system, secret information embedding device, secret information detection device, "Secret information embedding method and secret information detecting method".

  The invention of Patent Document 1 does not require a special seal, and does not need to manage an encryption key (for example, a password) for disclosure of secret information, and is intended to handle secret information. The embedding device encrypts the secret information using the unique information of the approver who is authorized to approve information disclosure as an encryption key.

The secret information detection device decrypts the secret information by using the unique information as a decryption key when the approver's unique information (for example, an approval stamp or a signature) is given to the printed document on the paper medium. indicate.
Japanese Patent Application Laid-Open No. 2004-364093.

  When decrypting confidential information embedded in a document by the technique of the above-mentioned Patent Document 1, since it is only whether or not all of the confidential information can be read, the level is set for the confidential information and the authority level for reading the confidential information Therefore, there is a problem that secret information that can be read cannot be selectively determined and processed depending on the situation.

  In addition to confidential information, even when creating a document with copying restrictions set by embedding information that prohibits copying in an electronic watermark, the copying prohibition level is set for each image area of the document that is prohibited from copying. There is a problem that the copying operation cannot be prohibited by determining the image area of the document that is prohibited from being copied according to the authority level for the copying operation.

  The present invention provides a plurality of levels for each operation type in order to specify a region where copying is prohibited or a region where decoding is prohibited according to the authority level of a user who copies a document and decrypts an encrypted document. It is an object of the present invention to provide a secret document processing apparatus that can embed the secret level set in (1) in a document with an electronic watermark.

  In order to solve the above-mentioned problem, the invention of claim 1 sets a secret level for each area of an original document in a secret document processing apparatus that creates a secret document by embedding an electronic watermark in the original document. Secret level setting means, electronic watermark embedding means for embedding an electronic watermark corresponding to the secret level for each area set by the secret level setting means for each area, and electronic watermark embedding by the electronic watermark embedding means And a secret document output means for outputting the secret document.

  According to a second aspect of the present invention, in the first aspect of the invention, the electronic watermark embedding unit embeds a copy-forgery-inhibited pattern image corresponding to the secret level for each region, and the secret document output unit has the copy-forgery-inhibited pattern image embedded therein. When the secret document is printed out and the secret document printed out by the secret document output means is copied, the secret level is analyzed for each area based on the copy-forgery-inhibited pattern image, and each area corresponding to the analyzed secret level is analyzed. And determining whether or not copying is possible.

  According to a third aspect of the invention, in the second aspect of the invention, when copying a secret document printed out by the secret document output means, the authority information for copying is input, and the authority information and the secret level input are input. Correspondingly, whether or not copying is possible is determined for each area.

According to a fourth aspect of the invention, in the second or third aspect of the invention, when copying a secret document printed out by the secret document output means, copying of an image in an area determined not to be copied is selectively prohibited. It is characterized by being.
According to a fifth aspect of the present invention, in the invention according to any one of the second to fourth aspects, the copy-forgery-inhibited pattern image is also copied when the secret document printed out by the secret document output means is copied.

  According to a sixth aspect of the present invention, in the first aspect of the invention, the electronic watermark embedding unit embeds the decryption key information corresponding to the secret level for each area, and the secret document output unit includes the decryption key information When decrypting the secret document that is embedded and the data of each area is encrypted with the encryption key information corresponding to the decryption key information, and the secret document output by the secret document output unit is decrypted, A secret level is analyzed for each area based on the decryption key information, and whether or not decryption is possible is determined for each area corresponding to the analyzed secret level.

  Further, the invention of claim 7 is the invention of claim 6, wherein the decryption authority information is inputted when the secret document printed out by the secret document output means is decrypted, and the inputted authority information and secret Whether or not decoding is possible is determined for each area corresponding to the level.

  The invention according to claim 8 is the invention according to claim 6 or 7, wherein when decoding the secret document printed out by the secret document output means, the decoding of the image in the area determined not to be decrypted is selected. It is prohibited to do so.

  The invention of claim 9 is the invention according to any one of claims 6 to 8, wherein the decryption key information is also output when outputting the decryption result of the secret document printed out by the secret document output means. Features.

  According to a tenth aspect of the present invention, in a secret document processing apparatus for copying a secret document in which a copy-forgery-inhibited pattern image corresponding to the secret level is embedded for each area, the authority information for copying is input when the secret document is copied. Each area based on the copy-forgery-inhibited pattern image extracted by the copy-forgery-inhibited pattern image extracting unit, the image reading unit for reading the image of the secret document, the copy-forgery-inhibited pattern image extracting unit for extracting the copy-forgery-inhibited pattern image from the image read by the image reading unit Analyzing means for analyzing each secret level, discriminating means for discriminating whether or not copying is possible for each area based on the secret level for each area analyzed by the analyzing means and authority information input by the authority information input means, and discriminating means And copying means for copying a secret document read by the image reading means based on whether or not copying is possible for each area by That.

  In the invention of claim 11, the decryption key information corresponding to the secret level is embedded in each area, and the data in each area is encrypted with the encryption key information corresponding to the decryption key information. In a secret document processing apparatus for decrypting a secret document, when decrypting the secret document, authority information input means for inputting authority information for the decryption, and reading means for reading the decryption key information from the secret document for each area And analyzing means for analyzing the secret level for each area based on the decryption key information read by the reading means, based on the secret level for each area analyzed by the analyzing means and the authority information input by the authority information input means Based on the determining means for determining whether or not each area can be decrypted, and on the decryption key information read by the reading means based on whether or not each area can be decrypted by the determining means. Characterized by comprising a decoding means for decoding the secret document.

  According to the secret document processing apparatus of the present invention, since a document in which information in an area in which a plurality of secret levels are set for each operation type is embedded with an electronic watermark is created, the document according to the authority level of the user who handles the distributed document is created. Copying and decoding restrictions can be implemented on a single document.

  An embodiment of a secret document processing apparatus according to the present invention will be described with reference to the accompanying drawings.

  A configuration example of a document processing system including the secret document processing apparatus of the present invention will be described with reference to FIG.

  In FIG. 1, a document printing apparatus 20 performs copying, decrypting, and decrypting results for a copy operation, a decrypting operation, and a decrypting result output operation for an issued document according to the authority level of the user who handles the document. The secret level embedded document 3 in which the secret level setting information 22 for restricting the output of the document is embedded in the image of the document by electronic watermark is printed and issued.

  The document copy reading device 30 is permitted to copy at the time of the copy operation based on the authority level of the user who performed the copy operation and decryption operation of the image of the secret level embedded document 3 issued by the document printing device 20. Copy the image of the area, copy the image of the area where copying is prohibited, or convert it to an encrypted image and conceal it. The image in the area where the decryption is prohibited is left in the encrypted state.

  The document printing apparatus 20 is configured to print the secret level embedded document 3 in which the secret level setting information 22 is embedded in the original document with an electronic watermark. The document printing apparatus main control unit 27 controls the entire document printing apparatus 20. A storage unit 21, a document printing device display unit 25, a document printing device input unit 26, and a document printing device document output unit 28.

The document printing apparatus display unit 25 has a setting screen for setting a secret level for each operation type for a desired area in the image of the original document, and a screen for instructing printing of the secret level embedded document 3 in which the secret level is set. A screen 251 for setting a secret level, which is an output device that displays various operation screens including the display data output from the document printing apparatus main control unit 27, has two types of screens shown in FIGS. is there.

FIG. 2 is a first example of an operation screen for setting a secret level. The user is an operation screen for setting a secret level for an arbitrary area in a specific page in an original document. Desired region 2513 to be set is selected, the type of operation to be restricted for the selected image (copy, decryption, output of decryption result) is selected from the operation type list 2511, and then the secret for the selected operation type is selected A level is selected from the secret level list 2512 and a secret level is set.

  FIG. 3 is a second example of the operation screen for setting the secret level, and is an example of the operation screen for setting the secret level in units of pages.

  The user selects at least one desired page (document) for setting the secret level from each page of the document displayed in a list on the screen or from the document, and sequentially selects the operation type list 2521 and the secret level list 2522. By performing a selection operation, the secret level setting information 22 is set in the selected page (document) 2523.

  Returning to FIG. 1 again, the document printing apparatus storage unit 21 stores secret level setting information 22, control information 23, and original document data 24.

  The control information 23 includes, for the setting operation of the secret level setting information 22, the type of operation for which the secret level can be set, the number of secret levels that can be set for each operation type, and the area in which the secret level can be set. The conditions are recorded, the format information of the secret level setting information 22 is recorded for the embedding process of the watermark image by the electronic watermark of the secret level setting information 22, and the secret information for the printing of the secret level embedded document 3 is recorded. As such, information relating to encryption processing for the area to be concealed is recorded.

  The secret level setting information 22 corresponding to the setting example 1 of the secret level setting information 22 is shown in FIG.

  The secret level setting information 22 includes area information 221, a copy restriction level 222, a decryption restriction level 223, and a decryption result output restriction level 224 as setting items.

  The area information 221 is an item in which information for specifying the area of the image in which the secret level setting information 22 is set in the secret level embedded document 3 is set. For example, an arbitrary area in a specific page in the original document When setting the secret level for the image, the data indicating the coordinates of the vertex closest to the origin of the selected rectangular area and the length in the direction of each coordinate axis when the origin is the upper left corner of the image of the secret level embedded document Is set.

  The copy restriction level 222 is set such that when the secret level embedded document 3 is copied by the document copy reading device 30, the secret level is set when a copy prohibition area is set for a user having a certain authority level or lower. It is an item to be set.

  The decryption restriction level 223 is a user who conceals an image by encrypting a part of the image of the secret level embedded document 3 and has authority over a certain level at the time of image decryption operation by the document copy reading device 30. This is an item in which the secret level is set when an area where the image encrypted only for the image is restored to the image of the original document 6 and the secret information is disclosed is set.

  The output restriction level 224 of the decryption result is a setting item that is effective for the area for which the decryption restriction level 223 is set, and is specified in the area information 221 when the secret level embedded document 3 is decrypted. This is an item for which a secret level is set when a restriction is set for outputting (printing output or electronic file output) the decryption result in the image of the original document 6.

  The document printing apparatus document output unit 28 is a printing apparatus that forms print data output from the document printing apparatus main control unit 27 and an image of the secret level embedded document 3 on paper under the control of the document printing apparatus main control unit 27.

  The document copy reading device 30 determines the area where the secret level is set based on the secret level for each operation type set in the secret level setting information 22 and the authority level of the user who handles the secret level embedded document 3. The document copying / reading device main control unit 34, the document copying / reading device image reading unit 36, the document copying / reading device document output unit 37, the document copying / reading device input unit 38, and the document copying / reading device display unit. 35. A document copy reading device storage unit 31 is provided.

  The document copying / reading apparatus main control unit 34 controls the entire document copying / reading apparatus 30, controls image reading of the secret level embedded document 3 with respect to the document copying / reading apparatus image reading unit 36, and reads the read image into the document copying / reading apparatus. Display control to be displayed on the display unit 35, save the read image or decoded image file in the storage unit 31, or print the read image or the decoded image in the document copy reading device document output unit 37 Take control.

  The document copy reading device image reading unit 36 reads the image of the secret level embedded document 3 at a predetermined resolution to generate read image data, and outputs the generated read image data to the document copy reading device main control unit 34.

  The document copy reading device input unit 38 is an input device for the user to give a copy instruction, a decryption instruction, etc. to the document copy reading device 30, and the input operation data of the detected user is input to the document copy reading device main control unit 34. Output to.

  The document copy reading device display unit 35 includes an operation screen for the secret level embedded document 3, a read image screen for the secret level embedded document 3, a user ID for acquiring the user authority level for the secret level embedded document 3, and a password input screen. This is an output device that displays various screens based on display data output from the document copy reading device main controller 34.

  The document copy reading device document output unit 37 generates a copy image of the secret level embedded document 3 or a decrypted image of the secret level embedded document 3 based on print data output from the document copy reading device main control unit 34. A printing apparatus for forming on a sheet.

  Control information 33 and an image file 39 are recorded in the document copy reading device storage unit 31.

  The control information 33 includes format information for reading the secret level of each area recorded in the secret level setting information 22 embedded in the watermark image of the secret level embedded document 3, and the secret level read from the secret level setting information 22. Information for identifying the correspondence relationship between the authority levels of the users and determining whether or not the user has the authority for the set secret level is previously negotiated with the document printing apparatus 20 and recorded. Is done.

The image file 39 is document data obtained by digitizing the image of the secret level embedded document 3 or document data obtained by digitizing the result of decrypting the secret level embedded document 3.
The user management information 41 is a database for registering and managing user information for copying and decrypting the secret level embedded document 3 and the authority level of the user. As shown in FIG. This is a database for registering and managing the authentication information 412 and the authority level 413 assigned to the user, and data access is appropriately performed from the document printing apparatus 20 and the document copy reading apparatus 30 respectively.

As shown in FIG. 5, the processing image for acquiring the authority level of the user who has performed user authentication is as follows. When the document copy reading device 30 detects a copy operation or decryption operation of the secret level embedded document 3, the user ID and password are detected. An input screen (352 in FIG. 5) prompting the user to input is output to the document copy reading device display unit 35.
When the user ID and password are input from the document copy reading device input unit 38, the user authentication information 412 corresponding to the input user ID 411 is read from the user management information 41, and the authentication information 412 is based on the password input by the user. When the user is authenticated, the authority level 413 corresponding to the user ID 411 is read to identify the authority level set for the user.

  Next, FIG. 6 shows an example of a copy process corresponding to the authority level of the user with respect to the secret level embedded document 3 in which the copy restriction level 222 is set in the secret level setting information 22, and the decryption restriction level is included in the secret level setting information 22. An example of the decryption process corresponding to the authority level of the user for the secret level embedded document 3 in which H.223 is set will be described with reference to FIG.

  6 and 7, there are three types of secret levels that can be set for various operations that can be set in the secret level setting information 22, and the secret level 1> secret level 2> secret level 3 in descending order of level. On the other hand, there are also three types of authority levels set for the user, and authority level 1> authority level 2> authority level 3 is set in descending order of authority, and authority level 1 has authority for all secret levels. It is assumed that authority level 2 has authority over secret level 2 or secret level 3, and authority level 3 has authority only over secret level 3.

  FIG. 6 shows a processing image when a user with a different authority level performs a copying operation on the secret level embedded document 3 in which the copy restriction level 222 is set in the secret level setting information 22.

  In FIG. 6, the secret level embedded document 3 includes an area in which the secret level 1 is set in the copy restriction level 222 (82 in FIG. 6), and an area in which the secret level 2 is set in the copy restriction level 222 (83 in FIG. 6). In addition, it has an image area (81 in FIG. 6) in which the secret level setting information 22 is embedded in the image of the original document 6 by electronic watermarking.

When the authority level 1 user performs the copying operation (91 in FIG. 6), all areas are copied, but the authority level 2 and authority level 3 users lower than the authority level 1 perform the copying operation. In the case (92 and 93 in FIG. 6), for the area without authority, an encrypted image or an image concealed by a filled image or the like is printed on a sheet.

  In FIG. 7, the secret level embedded document 3 is an encrypted area (72 in FIG. 7) in which the secret level 1 is set in the decryption restriction level 223 of the secret level setting information 22, and the decryption restriction of the secret level setting information 22. An area where the secret level 2 is set at the level 223 (73 in FIG. 7) and an area (71 in FIG. 7) in which the secret level setting information 22 is embedded in the image of the original document 6 by electronic watermarking. Have.

  The area where the secret level 1 is set in the decryption restriction level 223 (72 in FIG. 7) is restored to the original image only when the authority level of the user who performed the image reading operation is 1.

  In the area where the secret level 2 is set in the decryption restriction level 223 (73 in FIG. 7), the encrypted image becomes the original image when the authority level of the user who performed the image reading operation is 1 or authority level 2. Restored.

  Reference numeral 51 in FIG. 7 is a decryption result when the user authority level is 1, and reference numeral 52 in FIG. 7 is a decryption result when the user authority level is 2. Further, 53 in FIG. 7 is a decryption result when the user authority level is 3.

  Next, a procedure of processing for creating the secret level embedded document 3 by the document printing apparatus 20 will be described with reference to the flowchart of FIG.

  The document printing apparatus 20 reads the original document data 24, which is the original document of the secret level embedded document 3 in which the secret level setting information 22 is embedded, from the document printing apparatus storage unit 21 (S101), and sets the secret level setting information 22 setting screen ( The screens shown in FIGS. 2 and 3 are output to the document printer display unit 25 (S102).

  When the setting operation of the user on the setting screen of the secret level setting information 22 is detected by the document printing apparatus input unit 26, the area to be set for the secret level selected by the user, the operation type, and the secret level for the selected operation type are When the detected input data of the user operation is analyzed and discriminated, and the discriminated secret level setting target operation is copying (copying in step S103), the document printing apparatus 10 sets the secret set for the copy restriction level 222. The level is specified from the input data and recorded in the secret level setting information 22 (S104).

  When the operation type is output of the decryption result (output of the decryption result in step S103), the secret level value selected by the user is recorded in the decryption result output restriction level 224 in the secret level setting information 22 (S105). ).

  If the type of the secret level set by the user is decryption (decryption in step S103), the document printing apparatus 20 sets the secret level value selected by the user to the decryption restriction level 223 of the secret level setting information 22. The image is recorded (S106), and the image in the area where the secret level is set to the decryption restriction level 223 is encrypted and concealed (S107).

  The document printing apparatus 20 performs step S104, step S105, and step S106 by electronic watermarking on the image image created based on the original document data 24 (including the concealed image encrypted in step S107). A watermark image having a dot pattern for embedding the secret level setting information 22 created in the above process is created and synthesized, and image data of the secret level embedded document 3 is created (S108), and based on the created image data Then, print data of the secret level embedded document 3 is generated and output to the document printing apparatus document output unit 28 to print the secret level embedded document 3 (S109).

  In the flowchart shown in FIG. 8, the process of creating the secret level setting information 22 in the processes of steps S104, S105, and S106 is repeated until a plurality of secret level setting operations for a plurality of areas are completed. It is possible to add the area information that has been processed and the secret level is set to the secret level setting information 22, and after the setting operation of the secret level setting information 22 is completed, the secret information is again displayed at another opportunity. The secret level setting information 22 of the original document data 24 in which the level setting information 22 is set is read, and the content of the area information 221 recorded in the read secret level setting information 22 is corrected, or the area information 221 unit is read. It may be configured such that addition and deletion operations can be performed.

  Further, the flowchart shown in FIG. 8 shows an example in which the process of setting the secret level setting information 22 and the process of creating the secret level embedded document 3 based on the setting of the secret level setting information 22 are continuously performed. The two processes may be divided and executed individually.

  Next, the operation of copying and decrypting the secret level embedded document 3 by the document copy reading device 30 will be described with reference to the flowchart of FIG.

  When the document copy reading device 30 detects a copy operation or decryption operation of the secret level embedded document 3, the document copy reading device 30 reads and reads the image of the secret level embedded document 3 at a predetermined resolution by the image copy reading device image reading unit 36. Image data is created (S201).

  The document copy reading device 30 analyzes the read image data, extracts a watermark image of the secret level setting information 22 embedded by electronic watermark, and extracts the secret level setting information 22 from the dot pattern of the extracted watermark image. Based on the data reading format information recorded in the control information 23, the secret level for each area information 221 recorded in the restored secret level setting information 22 is read (S202).

  The document copy reading device 30 displays an input screen for user information (user ID, password) on the document copy reading device display unit 35 (S203).

  If no user information is input (NO in S204), the process is stopped. If an input operation for user information is detected (YES in S204), user authentication is performed based on the input user ID and password, and the user is authenticated. If so, the authority level 413 corresponding to the user ID is read from the user management information 41 (S205).

  Next, the operation type (copying operation, decoding operation) for the secret level embedded document 3 is determined.

  If the determined operation type is a copy operation (copying in S206), whether or not there is area information 221 in which the copy restriction level 222 is set in the secret level setting information 22 read from the secret level embedded document 3 in step S202. A determination is made (S207).

  If there is area information 221 in which the copy restriction level 222 is set in the secret level setting information 22 (YES in S207), the document copy reading device 30 prohibits copying for the user authority level acquired in the process of step S205. Whether there is an area is determined based on the secret level set in the copy restriction level 222. If there is an area for which copying is prohibited, the image of the area is encrypted or converted into a filled image. A copy image is created by performing image processing that is partially concealed (S208).

  When the creation of the copy image is completed, print data for forming the copy image on the paper is created, the print data of the created copy image is output to the document copy reading device document output unit 37, and the copy image is printed on the paper. (S209).

  Returning to the determination process in step S206 again, if the operation type is a decryption operation (decryption in S206), the document copy reading device 30 reads the secret level setting information 22 read from the secret level embedded document 3 in the process of step S202. Then, it is determined whether or not there is area information 221 in which the secret level is set in the decryption restriction level 223 (S210).

  If there is the area information 221 in which the secret level is set in the decryption restriction level 223, the encryption is performed based on the secret level set in the decryption restriction level 223 and the authority level of the user acquired in the process of step S205. Whether or not there is an area for restoring the converted image to the image of the original document 6 is determined for each area for which the secret level is set in the decryption restriction level 223, and there is an area to be restored to the image of the original document 6 If there is, the decoding process is performed to restore the original image (S211).

  The read image of the image reading result of the secret level embedded document 3 (or the restored image when decryption is performed in step S211) is displayed on the document copy reading device display unit 35 and the displayed read image is displayed. An operation menu for performing an output operation is also output to the document copy reading device display unit 35 (S212).

  If there is no document output operation for the read image by the user (NO in S213), the document copy reading apparatus 30 ends the display of the read image on the screen and ends the process.

  On the other hand, when an output operation is performed on the read image (YES in S213), the document copy reading apparatus 30 sets the secret level in the secret level setting information 22 read from the secret level embedded document 3 in the process of step S202. It is determined whether or not there is an output restriction level 224 of the decoding result for the region information 221 (S214).

  If there is an area where the output restriction level 224 of the decryption result is set (YES in S214), the document copy reading device 30 acquires the secret level set to the output restriction level 224 of the decryption result and the processing of step S205. Based on the authority level of the user, whether or not there is an area for which the output of the decryption result is prohibited is determined for each area information 221 in which the secret level is set in the output restriction level 224 of the decryption result. If there is an area where the output of the result is prohibited, a duplicate image is created by performing image processing to replace the image in the area with the encrypted image again (S215).

  Next, as a copy image output form, any process of saving the copy image as electronic data in the document copy reading device storage unit 31 or printing it on a sheet by the document copy reading device document output unit 37 by a user operation. It is determined based on the input operation of the user (S216).

  When an instruction operation for saving a duplicate image as electronic data is performed (digitization in S216), the document copy reading device 30 creates an image file 39 in which the duplicate image is digitized and creates a predetermined storage area of the recording unit 31. (S217).

  On the other hand, when the output form of the duplicate image is a print document (printed in S216), the document copy reading device 30 creates print data of the duplicate image based on the image data of the duplicate image, and the document copy reading device document output unit The generated print data is output to 37, and the duplicate document is printed (S218).

  In the copy or decryption of the secret level embedded document 3 in the document copy reading device 30 described in the above embodiment, the secret level setting information 22 is re-embedded and printed in the copy image and the copy image, and a new one is created. The secret level embedded document 3 may be created.

  INDUSTRIAL APPLICABILITY The secret document processing apparatus of the present invention can be used for an apparatus that prints a document in which information is embedded by an electronic watermark, and an apparatus that performs copying and image reading of a document in which information is embedded. This is effective when creating a document that determines the area that prohibits printing and the area where confidential information is exchanged using paper as a medium, depending on the authority level of the user who operates the copying, decrypting, and outputting of the decryption result of the document. .

1 is a block diagram showing a schematic configuration of a document processing system constituted by an apparatus to which a secret document processing apparatus of the present invention is applied. The figure which shows the 1st example of a secret level setting screen. The figure which shows the 2nd example of a secret level setting screen. The figure which shows the example of secret level setting information. The image figure which shows the example which acquires an authority level from user information. The figure which shows the process image at the time of performing the copy operation of the image by the user of a different authority level about the document in which the copy restriction was set to the secret level embedded document. The figure which shows the processing image when the decryption operation is performed by the user of a different authority level about the document in which the decryption restriction level was set to the secret level embedded document. 6 is a flowchart illustrating an operation of a secret level embedded document creation process performed by the document printing apparatus. 6 is a flowchart showing operations of an image reading process, a copying process, and a decoding process for a secret level embedded document by the document copy reading apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Document processing system 20 Document printing apparatus 21 Document printing apparatus memory | storage part 22 Secret level setting information 221 Area | region information 222 Copy restriction level 223 Decoding restriction level 224 Decoding result output restriction level 23 Control information 24 Original document data 25 Document printing apparatus Display unit 251 Secret level setting screen (area unit)
2511 Operation type list 2512 Secret level list 2513 Selection area 252 Secret level setting screen (per page)
2521 Operation Type List 2522 Secret Level List 2523 Secret Level Setting Target Page 26 Document Printing Device Input Unit 27 Document Printing Device Main Control Unit 28 Document Printing Device Document Output Unit 3 Secret Level Embedded Document 30 Document Copy Reading Device 31 Document Copy Reading Device Storage Unit 33 Control information 34 Document copy reading device main control unit 35 Document copy reading device display unit 351 Reading image display screen 352 User information input screen 36 Document copy reading device image reading unit 37 Document copy reading device Document output unit 38 Document copy reading device Input unit 39 Image file 4 Database 41 User management information 411 User ID
412 User authentication information 413 Authority level 5 Output document 51 Authority level 1 decrypted image 52 Secret level 2 decrypted image 53 Secret level 3 decrypted image 6 Original document 71 Secret level setting information embedding area 72 Secret level 1 setting area 73 Secret level 2 setting area 81 secret level setting information embedding area 82 secret level 1 setting area 83 secret level 2 setting area 91 authority level 1 copy image 92 secret level 2 copy image 93 secret level 3 copy image

Claims (11)

In a secret document processing apparatus that creates a secret document by embedding an electronic watermark in an original document,
A secret level setting means for setting a secret level for each area of the original document;
An electronic watermark embedding means for embedding an electronic watermark corresponding to the secret level for each area set by the secret level setting means for each area;
A secret document processing apparatus comprising: a secret document output unit that outputs a secret document in which the electronic watermark is embedded by the electronic watermark embedding unit. The electronic watermark embedding means is:
Embed a copy-forgery-inhibited pattern image corresponding to the secret level for each area,
The secret document output means includes
Print out the secret document in which the copy-forgery-inhibited pattern image is embedded,
When the secret document printed out by the secret document output means is copied, the secret level is analyzed for each area based on the copy-forgery-inhibited pattern image, and is copied for each area corresponding to the analyzed secret level. The secret document processing apparatus according to claim 1, wherein whether or not is possible is determined. When copying the secret document printed out by the secret document output means, input the authority information for copying, and determine whether or not copying is possible for each area corresponding to the input authority information and the secret level. The secret document processing apparatus according to claim 2, wherein: 4. The secret according to claim 2, wherein, when the secret document printed out by the secret document output means is copied, copying of an image in an area determined not to be copied is selectively prohibited. Document processing device. 5. The secret document processing apparatus according to claim 2, wherein the copy-forgery-inhibited pattern image is also copied when the secret document printed out by the secret document output unit is copied. The electronic watermark embedding means is:
Embedding decryption key information corresponding to the secret level for each area,
The secret document output means includes
Outputting the secret document in which the decryption key information is embedded and the data of each area is encrypted with the encryption key information corresponding to the decryption key information;
Upon decryption of the secret document printed out by the secret document output means, the secret level is analyzed for each area based on the decryption key information, and each area corresponding to the analyzed secret level is analyzed. The secret document processing apparatus according to claim 1, wherein whether or not decryption is possible is determined every time. When decrypting the secret document printed out by the secret document output means, the decryption authority information is input, and decryption is performed for each area corresponding to the input authority information and the secret level. The secret document processing apparatus according to claim 6, wherein whether or not it is possible is determined. 8. The decryption of an image of an area determined to be undecipherable is selectively prohibited when the secret document printed out by the secret document output unit is decrypted. The secret document processing device described. 9. The secret document processing apparatus according to claim 6, wherein the decryption key information is also output when outputting the decryption result of the secret document printed out by the secret document output unit. . In a secret document processing apparatus for copying a secret document in which a copy-forgery-inhibited pattern image corresponding to a secret level is embedded in each area,
Authority information input means for inputting authority information for copying when copying the secret document;
Image reading means for reading an image of the secret document;
A tint block image extracting unit for extracting the tint block image from an image read by the image reading unit;
Analyzing means for analyzing a secret level for each region based on the tint block image extracted by the tint block image extracting unit;
A discriminating unit for discriminating whether or not copying is possible for each area based on the secret level analyzed by the analyzing unit and the authority information input by the authority information input unit;
A secret document processing apparatus, comprising: a copying unit configured to copy a secret document read by the image reading unit based on whether or not copying can be performed for each area by the determination unit. A secret for decrypting a secret document in which decryption key information corresponding to a secret level is embedded in each area and data in each area is encrypted with the encryption key information corresponding to the decryption key information In a document processing device,
Authority information input means for inputting authority information for decryption when decrypting the secret document;
Reading means for reading the decryption key information from the secret document for each area;
Analyzing means for analyzing a secret level for each area based on the decryption key information read by the reading means;
A discriminating means for discriminating whether or not each area can be decrypted based on the secret level analyzed by the analyzing means and the authority information input by the authority information input means;
A secret document process comprising: a decrypting unit configured to decrypt the secret document based on decryption key information read by the reading unit based on whether or not each area can be decrypted by the determining unit. apparatus.

Images