Image processing device

Abstract

An image processing device (2) includes an image reading unit (11) and a control unit (10). When it is determined that the importance of image data is high according to a predetermined determination criterion, the control unit (10) executes, on the image data, a predetermined first correction process that makes all characters recognizable and a seal visible. When it is determined that the importance of the image data is low according to the predetermined determination criterion, the control unit (10) executes, on the image data, a predetermined second correction process that is different from the first correction process and makes all the characters visible.

Description

Image processing apparatus

[0001] The present invention relates to an image processing apparatus, and particularly to a technique for correcting printing.

[0002] In a document such as a form or a certificate where a company seal is stamped near a string such as a printed company name, the print may overlap a part of the string. When OCR (Optical Character Recognition) processing is performed on the image data obtained by scanning such a document, there is a problem that the accuracy of character recognition decreases due to the print.

[0003] In order to solve such a problem, for example, Patent Document 1 discloses a technique of performing image processing on a visible image obtained by irradiating a document with visible light using an invisible image obtained by irradiating the document with invisible light, thereby removing the printed portion and generating an image showing only the string.

[0004] Japanese Patent Application Laid-Open No. 2021-5162

[0005] By the way, in the technique disclosed in Patent Document 1, in order to remove the printed portion, it may become impossible to confirm that the document has been stamped based on the document image after image processing. Therefore, for important documents that require stamping, it is inconvenient, such as having to check the document again.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to improve the accuracy of character recognition by OCR processing for a document image including a print overlapping with characters, and to ensure confirmation of stamping for important documents.

[0007] An image processing apparatus according to one aspect of the present invention includes: an image reading unit that reads a document containing a seal impression overlapping with characters and generates image data representing the document image; and a control unit that, when it is determined that the importance of the image data is high according to predetermined criteria, performs a predetermined first correction process on the image data to make the characters recognizable and the seal impression visible, and when it is determined that the importance of the image data is low according to the criteria, performs a predetermined second correction process on the image data that is different from the first correction process and makes the characters recognizable.

[0008] According to the present invention, the accuracy of character recognition by OCR processing is improved for original document images that include seal impressions overlapping with characters, and for highly important documents, confirmation of seal impressions can be reliably performed.

[0009] This is a front cross-sectional view showing the structure of an image forming apparatus. This is a block diagram showing the configuration of an image forming apparatus. This is a diagram showing an example of a login screen. This is a diagram showing an example of a home screen. This is a diagram showing an example of a file name input screen. This is a flowchart showing the seal impression correction process. This is a flowchart showing the seal impression correction process. This is a flowchart showing the importance determination process. This is a flowchart showing the importance determination process. This is a flowchart showing the importance determination process. This is a flowchart showing the importance determination process. This is a flowchart showing the importance determination process. This is a diagram showing an example of a first selection screen. This is a diagram showing an example of a first confirmation screen. This is a diagram showing an example of a second selection screen. This is a diagram showing an example of a second confirmation screen. This is a diagram showing another example of a first selection screen. This is a diagram showing another example of a first confirmation screen. This is a diagram showing another example of a second selection screen. This is a diagram showing another example of a second confirmation screen.

[0010] Hereinafter, an image forming apparatus equipped with an image processing apparatus according to one embodiment of the present invention will be described with reference to the drawings.

[0011] [Overall Configuration of Image Forming Apparatus 1] Figure 1 is a front cross-sectional view showing the structure of the image forming apparatus 1. Referring to Figure 1, the image forming apparatus 1 is a multifunction device equipped with multiple functions such as a copy function, a transmission function, a printer function, and a facsimile function.

[0012] The image forming apparatus 1 includes an ADF (Auto Document Feeder) 6, an image reading unit 11, an image forming unit 12, a fixing unit 13, a paper feeding unit 14, a display unit 15, an operation unit 16, and a transport unit 17, etc.

[0013] The ADF 6 comprises a document tray 62 and a document transport unit 64. The document transport unit 64 transports documents placed on the document tray 62 one by one to the reading position of the image reading unit 11. The ADF 6 is configured to open and close the platen glass 7 by rotating vertically with the back of the paper surface in Figure 1 as the pivot point. The ADF 6 functions as a cover that holds down the document on the platen glass 7 from above.

[0014] The image reading unit 11 is a scanner that optically reads a document and generates image data showing the document image. The image reading unit 11 reads a document that is transported by the ADF 6 or a document that is placed on the platen glass 7.

[0015] The image forming unit 12 includes a photoreceptor drum, a charging device, an exposure device, a developing device, and a transfer device. Based on image data generated by the image reading unit 11, or image data input via the communication unit 22, the image forming unit 12 forms a toner image on the paper P that is transported along the transport path T by the transport unit 17.

[0016] The fixing unit 13 fixes the toner image on the paper P, which has a toner image formed on it by the image forming unit 12, by heating and pressurizing it. The paper P, on which the toner image has been fixed by the fixing unit 13 and an image has been formed, is discharged into the discharge tray 8.

[0017] The paper feeding unit 14 includes a manual feed tray and multiple paper feed cassettes. The paper feeding unit 14 uses a pickup roller to pull out sheets of paper P stored in one of the multiple paper feed cassettes or placed in the manual feed tray one by one and feeds them into the transport path T. Note that the paper P is not limited to paper media and may be, for example, an OHP (Overhead Projector) sheet.

[0018] The display unit 15 is a liquid crystal display or an organic light-emitting diode (OLED) display, etc. The display unit 15 displays various screens.

[0019] The operation unit 16 includes a plurality of hard keys, such as a start key 16A, for inputting instructions to start each process that can be executed by the image forming apparatus 1. The operation unit 16 also includes a touch panel 16B that is placed on top of the display unit 15. User instructions are input to the operation unit 16.

[0020] The transport unit 17 includes a transport roller pair 17A and an discharge roller pair 17B, etc., and a transport motor. The transport roller pair 17A and the discharge roller pair 17B, etc. are rotated by the drive of the transport motor, so that the paper P fed by the paper feeding unit 14 is transported along the transport path T.

[0021] Figure 2 is a block diagram showing the configuration of the image forming apparatus 1. Referring to Figure 2, the image forming apparatus 1 includes a control unit 100. The control unit 100 includes a processor, RAM (Random Access Memory), and ROM (Read Only Memory), etc. The processor is, for example, a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or an ASIC (Application Specific Integrated Circuit).

[0022] The control unit 100 functions as a control unit 10 when a control program stored in ROM or HDD (Hard Disk Drive) 18 is executed by the processor. The control unit 10 controls the operation of each part of the image forming apparatus 1 and communication with a PC (Personal Computer) 23, etc., connected via a network. The control unit 10 may be configured using logic circuits instead of operating based on the control program.

[0023] The control unit 100 is electrically connected to the ADF 6, image reading unit 11, image forming unit 12, fixing unit 13, paper feeding unit 14, display unit 15, operation unit 16, transport unit 17, HDD 18, image processing unit 19, image memory 20, facsimile communication unit 21, and communication unit 22, etc.

[0024] In this embodiment, the control unit 100, including the control unit 10, ADF 6, image reading unit 11, display unit 15, operation unit 16, HDD 18, image processing unit 19, image memory 20, facsimile communication unit 21, and communication unit 22, functions as an image processing device 2.

[0025] The HDD 18 is a large-capacity storage device for storing various data such as image files. The HDD 18 stores various control programs for realizing the general operation of the image forming apparatus 1. As part of the above-mentioned control programs, the HDD 18 stores a correction program for performing the impression correction process described later, and an OCR program for performing general OCR processing.

[0026] HDD 18 stores usernames and passwords in association with authentication information. HDD 18 also stores attribute information associated with usernames. Attribute information indicates the user's attributes, such as job titles like president, executive, manager, or general employee, or the name of the company to which the user belongs. HDD 18 also stores location information indicating the installation location of the image forming apparatus 1. Location information may include, for example, the president's office, a general floor, or an open space.

[0027] Each HDD18 pre-stores a primary character information, primary attribute, primary location, and primary seal image, each indicating high importance. Here, the primary character information represents the string "contract." The primary character information is not limited to a string; it may be a single character. The primary attribute represents "president," "officer," "person in charge," and "other company." The primary location information represents "president's office." The primary seal image represents a predetermined seal image showing the company's official seal and a predetermined seal image showing the bank seal.

[0028] HDD18 pre-stores secondary character information, secondary attributes, secondary locations, and secondary seal images, each indicating low importance. Here, the secondary character information represents the string "Invoice". The secondary character information is not limited to a string; it may be a single character. The secondary attribute represents "General Employee". The secondary locations represent "General Floor" and "Open Space". The secondary seal images are predetermined seal images representing personal seals, predetermined seal images representing company seals, and predetermined seal images representing rubber stamps.

[0029] The image processing unit 19 performs image processing on the image data generated by the image reading unit 11 as needed. The image memory 20 temporarily stores the image data generated by the image reading unit 11. The facsimile communication unit 21 transmits and receives image data via a public network.

[0030] The communication unit 22 includes a communication module such as a LAN (Local Area Network) board. The control unit 10 performs data communication with external devices such as a PC 23 that are connected via the network through the communication unit 22.

[0031] Each part of the image forming apparatus 1 is connected to a power supply. When the user turns on the power, power is supplied from the power supply to each part of the image forming apparatus 1.

[0032] [Operation] (Seal Impression Correction Processing) The operation of the image forming apparatus 1 during the execution of seal impression correction processing will be described below with reference to Figures 3 to 11, etc.

[0033] When the power to the image forming apparatus 1 is turned on, the control unit 10 displays the login screen 30 shown in Figure 3 on the display unit 15. When the user enters a username and password as user information using the touch panel 16B, the control unit 10 displays the entered username in box 32 and the entered password in box 34.

[0034] Next, when the user touches the OK key 36, the control unit 10 receives an authentication start instruction and determines whether the entered username and password match the authentication information pre-stored in the HDD 18. In this case, the control unit 10 determines that the entered username and password match the authentication information and displays the home screen 40 shown in Figure 4 on the display unit 15. If the username and password do not match the authentication information, the control unit 10 does not permit login to the image forming apparatus 1.

[0035] When the user touches key 42 to select the shadow correction function, the control unit 10 receives a command to display the file name input screen and displays the file name input screen 50 shown in Figure 5 on the display unit 15. When the user enters a file name using the touch panel 16B, the control unit 10 displays the entered file name in box 52.

[0036] Next, when the user places the document containing the seal impression overlapping with the text onto the platen glass 7 and presses the start key 16A, the control unit 10 receives the entered file name and the instruction to start the seal impression correction process, and starts executing the seal impression correction process shown in Figures 6A and 6B. In the seal impression correction process, as shown in Figure 6A, the control unit 10 first has the image reading unit 11 read the document on the platen glass 7 and generate image data (step S10). After the processing in step S10, the control unit 10 starts executing the importance determination process shown in Figures 7A to 7E (step S11).

[0037] (1) Importance determination process (1-1) Determination based on file name As shown in Figure 7A, in the importance determination process, the control unit 10 first obtains the file name entered via the touch panel 16B (step S40). After the process in step S40, the control unit 10 determines whether the obtained file name contains the first character information (step S41).

[0038] If the retrieved file name contains the string "contract", the control unit 10 determines that the retrieved file name contains the first character information (YES in step S41) and determines that the importance of the image data is "high" (step S42). After processing in step S42, the control unit 10 terminates the importance determination process.

[0039] If the control unit 10 determines that the acquired file name does not contain the first character information (NO in step S41), it determines whether the acquired file name contains the second character information (step S43). If the acquired file name contains the string "invoice", the control unit 10 determines that the acquired file name contains the second character information (YES in step S43) and determines that the importance of the image data is "low" (step S44). After processing in step S44, the control unit 10 terminates the importance determination process.

[0040] (1-2) Determination based on attribute information On the other hand, if it is determined that the acquired file name does not contain second character information (NO in step S43), as shown in Figure 7B, the control unit 10 acquires attribute information corresponding to the username entered via the touch panel 16B from the HDD 18 (step S45). After processing in step S45, the control unit 10 determines whether the acquired attribute information indicates the first attribute (step S46).

[0041] If the acquired attribute information indicates "President," "Executive," "Person in Charge," or "Another Company," the control unit 10 determines that the acquired attribute information indicates the first attribute (YES in step S46), and determines that the importance of the image data is "high" (step S47). After processing in step S47, the control unit 10 terminates the importance determination process.

[0042] If the control unit 10 determines that the acquired attribute information does not indicate the first attribute (NO in step S46), it determines whether the acquired attribute information indicates the second attribute (step S48). If the acquired attribute information indicates "general employee", the control unit 10 determines that the acquired attribute information indicates the second attribute (YES in step S48) and determines that the importance of the image data is "low" (step S49). After processing in step S49, the control unit 10 terminates the importance determination process.

[0043] (1-3) Determination Based on Location Information On the other hand, when it is determined that the acquired attribute information does not indicate the second attribute (NO in step S48), as shown in FIG. 7C, the control unit 10 acquires location information from the HDD 18 (step S50). After the processing of step S50, the control unit 10 determines whether the acquired location information indicates the first location (step S51).

[0044] When the acquired location information indicates the "president's office", the control unit 10 determines that the acquired location information indicates the first location (YES in step S51), and determines that the importance of the image data is "high" (step S52). After the processing of step S52, the control unit 10 ends the importance determination process.

[0045] When the control unit 10 determines that the acquired location information does not indicate the first location (NO in step S51), it determines whether the acquired location information indicates the second location (step S53). When the acquired location information indicates the "general floor" or "open space", the control unit 10 determines that the acquired location information indicates the second location (YES in step S53), and determines that the importance of the image data is "low" (step S54). After the processing of step S54, the control unit 10 ends the importance determination process.

[0046] (1-4) Determination Based on the Recognized String On the other hand, when it is determined that the acquired location information does not indicate the second location (NO in step S53), as shown in FIG. 7D, the control unit 10 performs OCR processing on the image data generated by the image reading unit 11 to recognize the string included in the original image indicated by the image data (step S55). After the processing of step S55, the control unit 10 determines whether the recognized string includes the first character information (step S56).

[0047] When the recognized string includes the string "contract", the control unit 10 determines that the recognized string includes the first character information (YES in step S56), and determines that the importance of the image data is "high" (step S57). After the processing of step S57, the control unit 10 ends the importance determination process.

[0048] When the control unit 10 determines that the recognized character string does not contain the first character information (NO in step S56), it determines whether the recognized character string contains the second character information (step S58). When the recognized character string contains the character string "claim form", the control unit 10 determines that the recognized character string contains the second character information (YES in step S58), and determines that the importance of the image data is "low" (step S59). After the processing of step S59, the control unit 10 ends the importance determination process.

[0049] (1-5) Determination Based on Stamp Images On the other hand, when it is determined that the recognized character string does not contain the second character information (NO in step S58), as shown in FIG. 7E, the control unit 10 uses the first stamp image and the second stamp image stored in the HDD 18 to perform general template matching on the original image shown by the image data (step S60). After the processing of step S60, the control unit 10 determines whether the original image contains the first stamp image based on the result of the template matching (step S61).

[0050] When the original image contains a stamp image of "company seal" or "bank seal", the control unit 10 determines that the original image contains the first stamp image (YES in step S61), and determines that the importance of the image data is "high" (step S62). After the processing of step S62, the control unit 10 ends the importance determination process.

[0051] When the control unit 10 determines that the original image does not contain the first stamp image (NO in step S61), it determines whether the original image contains the second stamp image (step S63). When the original image contains a stamp image of "signature", "company seal", or "rubber stamp", the control unit 10 determines that the original image contains the second stamp image (YES in step S63), and determines that the importance of the image data is "low" (step S64). After the processing of step S64, the control unit 10 ends the importance determination process.

[0052] On the other hand, when it is determined that the original image does not contain the second stamp image (NO in step S63), the control unit 10 determines that the importance of the image data is "unknown" (step S65). After the processing of step S65, the control unit 10 ends the importance determination process.

[0053] (2) When the importance of the image data is high, after the importance determination process in step S11 is completed, the control unit 10 determines whether the importance of the image data is high or not based on the determination result of the importance determination process (step S12). If the determination result of the importance determination process is "high", the control unit 10 determines that the importance of the image data is high (YES in step S12) and displays the first selection screen 80 shown in Figure 8 on the display unit 15 (step S13).

[0054] The first selection screen 80 is a screen that allows the user to select whether or not to perform a predetermined first correction process on the image data, which makes the entire character recognizable and the seal impression visible. The control unit 10 causes the display unit 15 to display a message 82 indicating the content of the first correction process (in this case, the first seal impression movement process described later) and an image 84 showing the string and the seal impression overlapping a part of the string on the first selection screen 80. The control unit 10 obtains the image 84, for example, by extracting an image of a predetermined area from the original image shown by the image data.

[0055] After the processing in step S13, the control unit 10 repeatedly determines that it has not received an instruction to execute the first correction process (NO in step S14) and determines that it has not received an instruction not to execute the first correction process (NO in step S15) until the OK key 86 or Cancel key 88 on the first selection screen 80 is touched.

[0056] In this situation, when the user touches the OK key 86, the control unit 10 determines that it has received an instruction to execute the first correction process (YES in step S14) and executes the first correction process (step S16). In this case, as the first correction process, the control unit 10 extracts the text and the seal impression from the image 84 based on, for example, a difference in color (difference in RGB values), and executes a first seal impression movement process to move the seal impression to a position where it does not overlap with the text.

[0057] In this case, the control unit 10 extracts the black portion as a string of characters and the vermilion or red portion as the seal impression in the first seal impression movement process. The control unit 10 moves the extracted vermilion or red portion (i.e., the seal impression) to a position where it does not overlap with the extracted black portion (i.e., the string of characters).

[0058] After the processing in step S16, the control unit 10 displays the first confirmation screen 90 shown in Figure 9 on the display unit 15 (step S17). The control unit 10 displays a message 92 indicating the content of the first correction process (in this case, the first seal impression movement process) and the first image 94 generated by executing the first seal impression movement process on the image 84 on the first confirmation screen 90. The first image 94 displays the entire string of characters in a recognizable manner and the seal impression in a visible manner.

[0059] After the processing in step S17, the control unit 10 repeatedly determines that it has not received an instruction to continue the first correction process (NO in step S18) and determines that it has not received an instruction to not continue the first correction process (NO in step S19) until the OK key 96 or the Cancel key 98 on the first confirmation screen 90 is touched.

[0060] In this situation, when the user touches the OK key 96, the control unit 10 determines that it has received an instruction to continue the first correction process (YES in step S18), generates image data showing the original document image in which image 84 has been replaced with image 94, and stores it in the HDD 18 (step S20). After the processing in step S20, the control unit 10 terminates the imprint correction process.

[0061] On the other hand, if the user touches the cancel key 88 on the first selection screen 80, the control unit 10 determines that it has received an instruction not to execute the first correction process (YES in step S15) and terminates the seal impression correction process. In this case, the control unit 10 stores the image data generated by the image reading unit 11 in the HDD 18 without performing the first correction process on the image data.

[0062] Furthermore, if the user touches the cancel key 98 on the first confirmation screen 90, the control unit 10 determines that it has received an instruction not to continue the first correction process (YES in step S19) and terminates the seal impression correction process. In this case, the control unit 10 does not continue the first correction process on the image data generated by the image reading unit 11, and stores the image data on which the first correction process has not been performed in the HDD 18.

[0063] (3) When the importance of the image data is low If the result of the importance determination process is "low", the control unit 10 determines that the importance of the image data is not high (NO in step S12), and as shown in Figure 6B, determines that the importance of the image data is low (YES in step S21), and displays the second selection screen 101 shown in Figure 10 on the display unit 15 (step S22).

[0064] The second selection screen 101 is a screen that allows the user to select whether or not to perform a predetermined second correction process on the image data, which is different from the first correction process and makes the entire character recognizable. The control unit 10 causes the display unit 15 to display a message 102 indicating the content of the second correction process (in this case, the seal impression removal process described later) and an image 104 showing the string and the seal impression overlapping a part of the string on the second selection screen 101. The control unit 10 obtains the image 104, for example, by extracting an image of a predetermined area from the original image shown by the image data.

[0065] After the processing in step S22, the control unit 10 repeatedly determines that it has not received an instruction to execute the second correction process (NO in step S23) and determines that it has not received an instruction not to execute the second correction process (NO in step S24) until the OK key 106 or Cancel key 108 on the second selection screen 101 is touched.

[0066] In this situation, when the user touches the OK key 106, the control unit 10 determines that it has received an instruction to execute the second correction process (YES in step S23) and executes the second correction process (step S25). In this case, as the second correction process, the control unit 10 extracts the text and the seal impression from the image 104 and executes a seal impression removal process that removes the seal impression from the original image, leaving the text.

[0067] After the processing in step S25, the control unit 10 displays the second confirmation screen 110 shown in Figure 11 on the display unit 15 (step S26). The control unit 10 displays on the display unit 15 a message 112 indicating the content of the second correction process (in this case, the seal impression removal process) and a second image 114 generated by performing the seal impression removal process on the image 104 on the second confirmation screen 110. The second image 114 displays the entire string of characters in a recognizable manner.

[0068] After the processing in step S26, the control unit 10 repeatedly determines that it has not received an instruction to continue the second correction process (NO in step S27) and determines that it has not received an instruction to not continue the second correction process (NO in step S28) until the OK key 116 or the Cancel key 118 on the second confirmation screen 110 is touched.

[0069] In this situation, when the user touches the OK key 116, the control unit 10 determines that it has received an instruction to continue the second correction process (YES in step S27), generates image data showing the original document image in which image 104 has been replaced with image 114, and stores it in the HDD 18 (step S29). After the processing in step S29, the control unit 10 terminates the imprint correction process.

[0070] On the other hand, if the user touches the cancel key 108 on the second selection screen 101, the control unit 10 determines that it has received an instruction not to execute the second correction process (YES in step S24) and terminates the seal impression correction process. In this case, the control unit 10 stores the image data generated by the image reading unit 11 in the HDD 18 without performing the second correction process on the image data.

[0071] Furthermore, if the user touches the cancel key 118 on the second confirmation screen 110, the control unit 10 determines that it has received an instruction not to continue the second correction process (YES in step S28) and terminates the seal impression correction process. In this case, the control unit 10 does not continue the second correction process on the image data generated by the image reading unit 11, and stores the image data for which the second correction process has not been performed in the HDD 18.

[0072] (4) If the importance of the image data is unknown, if the result of the importance determination process is "unknown", the control unit 10 determines that the importance of the image data is not low (NO in step S21) and displays an error message on the display unit 15, such as "The importance of the original is unknown, so the seal impression correction cannot be performed." (step S30). After the processing in step S30, the control unit 10 terminates the seal impression correction process. In this case, the control unit 10 stores the image data generated by the image reading unit 11 in the HDD 18 without performing the second correction process on the image data.

[0073] According to the above embodiment, if the control unit 10 determines that the importance of the image data is high according to predetermined criteria, it performs a predetermined first correction process on the image data to make the entire character recognizable and the seal impression visible. If the control unit 10 determines that the importance of the image data is low according to predetermined criteria, it performs a predetermined second correction process on the image data, which is different from the first correction process, to make the entire character visible.

[0074] This improves the accuracy of character recognition using OCR processing for original document images that include seal impressions overlapping with text, and also ensures reliable verification of seal impressions for high-priority original document images.

[0075] Furthermore, according to the above embodiment, the control unit 10 determines that the importance is high if the file name entered via the operation unit 16 contains first character information, and determines that the importance is low if the file name entered via the operation unit 16 contains second character information. This makes it easy to determine the importance of the image data.

[0076] Furthermore, according to the above embodiment, the control unit 10 acquires attribute information corresponding to user information input via the operation unit 16, determines that the importance is high if the acquired attribute information indicates a first attribute, and determines that the importance is low if the acquired attribute information indicates a second attribute. This makes it easy to determine the importance of image data.

[0077] Furthermore, according to the above embodiment, the control unit 10 acquires location information indicating the installation location of the image forming apparatus 1, determines that the importance is high if the acquired location information indicates a first location, and determines that the importance is low if the acquired location information indicates a second location. This makes it possible to easily determine the importance of the image data.

[0078] Furthermore, according to the above embodiment, the control unit 10 recognizes the string of characters contained in the original image, determines that the recognized string of characters is of high importance if it contains first character information, and determines that it is of low importance if it contains second character information. This makes it possible to easily determine the importance of the image data.

[0079] Furthermore, according to the above embodiment, the control unit 10 determines that the original image is of high importance if it includes a first seal image, and determines that it is of low importance if it includes a second seal image. This makes it easy to determine the importance of the image data.

[0080] Furthermore, according to the above embodiment, if the control unit 10 determines that the importance of the image data is high, it displays a message 92 indicating the content of the first correction process and a first image 94 indicating the processing result of the first correction process on the display unit 15. If the control unit 10 determines that the importance of the image data is low, it displays a message 112 indicating the content of the second correction process and a second image 114 indicating the processing result of the second correction process on the display unit 15. As a result, the user can easily and reliably confirm the content and processing result of the first correction process, or the content and processing result of the second correction process, thereby further improving user convenience.

[0081] (First Modification) The first modification of the above embodiment has the same configuration as the above embodiment, except that the display content of the display unit 15 in the seal impression correction process and the content of the first correction process and the second correction process are different. The same configuration as the above embodiment will not be described again below.

[0082] [Operation] The operation of the image forming apparatus 1 during the execution of the seal impression correction process in the first modified example will be described below with reference to Figures 12 to 15, etc.

[0083] (1) If the importance of the image data is high, the control unit 10 determines that the importance of the image data is high (YES in step S12), and in step S13, displays the first selection screen 120 shown in Figure 12 on the display unit 15 instead of the first selection screen 80. The first selection screen 120 is a screen that allows the user to select the processing to be performed on the image data generated by the image reading unit 11.

[0084] The control unit 10 causes the display unit 15 to display the following checkboxes on the first selection screen 120: a checkbox 122A for selecting whether to perform the first correction process on the image data; a checkbox 122B for selecting whether to perform the first seal impression movement process as the first correction process on the image data; and a checkbox 122C for selecting whether to perform the seal impression density change process, which will be described later, as the first correction process on the image data.

[0085] After the processing in step S13, the control unit 10 repeatedly determines that it has not received an instruction to execute the first correction process (NO in step S14) and determines that it has not received an instruction not to execute the first correction process (NO in step S15) until one of the checkboxes 122A, 122B, or 122C and the OK key 124 on the first selection screen 120 are touched.

[0086] In this situation, when the user checks checkbox 122B or checkbox 122C and touches the OK key 124, the control unit 10 determines that it has received an instruction to execute the first correction process (YES in step S14) and executes the first correction process (step S16).

[0087] Specifically, if the control unit 10 detects that checkbox 122B is checked, it executes the first seal impression movement process described above on image 84. On the other hand, if the control unit 10 detects that checkbox 122C is checked, it extracts the text and seal impression from image 84 and executes a seal impression density change process to reduce the density of the seal impression. If the seal impression density change process is executed in step S16, in step S17, the control unit 10 displays the first confirmation screen 130 shown in Figure 13 on the display unit 15 instead of the first confirmation screen 90.

[0088] The control unit 10 causes the display unit 15 to display a message 132 indicating the content of the first correction process (in this case, the seal impression density change process), a first image 134 generated by performing the seal impression density change process on the image 84, an OK key 136 for inputting an instruction to continue the first correction process, and a cancel key 138 for inputting an instruction not to continue the first correction process on the first confirmation screen 130. The first image 134 displays the entire string of characters in a recognizable manner and the seal impression in a visible manner.

[0089] When the user touches the OK key 136, the control unit 10 determines that it has received an instruction to continue the first correction process (YES in step S18), and in step S20 generates image data showing the original image in which image 84 has been replaced with image 134, and stores it in the HDD 18.

[0090] On the other hand, if the user checks checkbox 122A and touches the OK key 124, the control unit 10 determines that it has received an instruction not to execute the first correction process (YES in step S15) and terminates the seal impression correction process. Also, if the user touches the cancel key 138 on the first confirmation screen 130, the control unit 10 determines that it has received an instruction not to continue the first correction process (YES in step S19) and terminates the seal impression correction process.

[0091] (2) When the importance of the image data is low, if the control unit 10 determines that the importance of the image data is low (YES in step S21), in step S22, it displays the second selection screen 140 shown in Figure 14 on the display unit 15 instead of the second selection screen 101. The second selection screen 140 is a screen that allows the user to select the processing to be performed on the image data generated by the image reading unit 11.

[0092] The control unit 10 causes the display unit 15 to display a checkbox 142A for selecting whether to perform the second correction process on the image data, a checkbox 142B for selecting whether to perform the second seal impression movement process, described later, as the second correction process on the image data, and a checkbox 142C for selecting whether to perform the seal impression deletion process described above as the second correction process on the image data, on the second selection screen 140.

[0093] After the processing in step S22, the control unit 10 repeatedly determines that it has not received an instruction to execute the second correction process (NO in step S23) and determines that it has not received an instruction not to execute the second correction process (NO in step S24) until one of the checkboxes 142A, 142B, or 142C and the OK key 144 on the first selection screen 140 are touched.

[0094] In this situation, when the user checks checkbox 142B or checkbox 142C and touches the OK key 144, the control unit 10 determines that it has received an instruction to execute the second correction process (YES in step S23) and executes the second correction process (step S25).

[0095] Specifically, if the control unit 10 detects that checkbox 142B is checked, it extracts the text and the seal impression from image 104 and executes a second seal impression movement process to move the seal impression behind the text. On the other hand, if the control unit 10 detects that checkbox 142C is checked, it executes the above-described seal impression deletion process on image 104. If the second seal impression movement process is executed in step S25, in step S26, the control unit 10 displays the second confirmation screen 150 shown in Figure 15 on the display unit 15 instead of the second confirmation screen 110.

[0096] The control unit 10 causes the display unit 15 to display a message 152 indicating the content of the second correction process (in this case, the second seal impression movement process) on the second confirmation screen 150, an image 154 generated by executing the second seal impression movement process on the image 104, an OK key 156 for inputting an instruction to continue the second correction process, and a cancel key 158 for inputting an instruction not to continue the second correction process. The image 154 displays the text in a recognizable manner and the seal impression in a visible manner.

[0097] When the user touches the OK key 156, the control unit 10 determines that it has received an instruction to continue the second correction process (YES in step S27), and in step S29 generates image data showing the original image in which image 104 has been replaced with image 154, and stores it in the HDD 18.

[0098] On the other hand, if the user checks checkbox 142A and touches the OK key 144, the control unit 10 determines that it has received an instruction not to perform the second correction process (YES in step S24) and terminates the seal impression correction process. Also, if the user touches the cancel key 158 on the second confirmation screen 150, the control unit 10 determines that it has received an instruction not to continue the second correction process (YES in step S28) and terminates the seal impression correction process.

[0099] According to the first modified example, the control unit 10 performs a first seal impression movement process or a seal impression density change process as a first correction process, and performs a seal impression deletion process or a second seal impression movement process as a second correction process. This reliably improves the accuracy of character recognition by OCR processing for original images that include seal impressions overlapping with characters, and makes it possible to more reliably confirm the presence of seals in high-priority original images.

[0100] Furthermore, according to the first modified version, the user can select a process to be executed from among a plurality of first correction processes via the first selection screen 120. The user can also select a process to be executed from among a plurality of second correction processes via the second selection screen 140. As a result, user convenience is further improved.

[0101] (Other Modifications) In the above embodiment, the control unit 10 determined importance using the file name, attribute information, location information, recognized string, and template matching in that order, but the present invention is not limited to such an embodiment. The control unit 10 may determine importance using at least one of the file name, attribute information, location information, recognized string, and template matching, and the order of determination may be different.

[0102] The configuration and processing of the above embodiment shown with reference to Figures 1 to 15 are merely one embodiment of the present invention and are not intended to limit the present invention to such configuration and processing.

Claims

1. An image processing apparatus comprising: an image reading unit that reads a document containing a seal impression overlapping with characters and generates image data representing the document image; and a control unit that, when it is determined that the importance of the image data is high according to predetermined criteria, performs a predetermined first correction process on the image data to make the characters recognizable and the seal impression visible, and when it is determined that the importance of the image data is low according to the criteria, performs a predetermined second correction process on the image data, which is different from the first correction process, to make the characters recognizable.

2. The image processing apparatus according to claim 1, further comprising: a storage unit that stores predetermined first character information indicating high importance and predetermined second character information indicating low importance; and an operation unit into which user instructions are input, wherein the control unit determines that the importance is high if the file name input via the operation unit includes the first character information, and determines that the importance is low if the file name input via the operation unit includes the second character information.

3. The image processing apparatus according to claim 1, further comprising: a storage unit that stores in advance predetermined first attributes indicating high importance and predetermined second attributes indicating low importance; and an operation unit into which user instructions are input, wherein the control unit acquires attribute information corresponding to user information input via the operation unit, determines that the importance is high if the acquired attribute information indicates the first attribute, and determines that the importance is low if the acquired attribute information indicates the second attribute.

4. The image processing apparatus according to claim 1, further comprising a storage unit that stores in advance a predetermined first location indicating high importance and a predetermined second location indicating low importance, wherein the control unit acquires location information indicating the installation location of the image processing apparatus, determines that the importance is high if the acquired location information indicates the first location, and determines that the importance is low if the acquired location information indicates the second location.

5. The image processing apparatus according to claim 1, further comprising a storage unit that stores in advance predetermined first character information indicating high importance and predetermined second character information indicating low importance, wherein the control unit recognizes a character string contained in the original image, determines that the recognized character string is of high importance if it contains the first character information, and determines that the recognized character string is of low importance if it contains the second character information.

6. The image processing apparatus according to claim 1, further comprising a storage unit that stores in advance a predetermined first seal image indicating high importance and a predetermined second seal image indicating low importance, wherein the control unit determines that the original image is of high importance if it includes the first seal image, and determines that the original image is of low importance if it includes the second seal image.

7. The image processing apparatus according to claim 1, further comprising a display unit, wherein the control unit causes the display unit to display the contents of the first correction process and a first image showing the processing result of the first correction process when it determines that the importance of the image data is high, and causes the display unit to display the contents of the second correction process and a second image showing the processing result of the second correction process when it determines that the importance of the image data is low.

8. The image processing apparatus according to claim 1, wherein the control unit performs, as a first correction process, a first imprint movement process which extracts the characters and the imprint from the original image and moves the imprint to a position where it does not overlap the characters, or an imprint density change process which extracts the characters and the imprint from the original image and reduces the density of the imprint; and as a second correction process, an imprint deletion process which extracts the characters and the imprint from the original image and deletes the imprint from the original image, leaving the characters, or a second imprint movement process which extracts the characters and the imprint from the original image and moves the imprint to the back of the characters.

9. The image processing apparatus according to claim 1, further comprising a display unit, wherein the control unit causes the display unit to display a message indicating that the importance of the image data is unknown if it is unable to determine the importance of the image data.

Images