JP2014142955A - Mark detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect a mark on a manuscript such as a mark sheet at a more reduced cost than a conventional one without requesting a troublesome operation to a user.SOLUTION: A multifunction machine 1 comprises: a difference calculation unit 103 for calculating the difference between both pieces of reading data of a blank mark sheet and a filled mark sheet read by a manuscript reading unit 5; and a domain determination unit 104 for determining a domain, in which the difference calculated by the difference calculation unit 103 becomes a value larger than a predetermined value and gathered, as a mark sheet domain for performing conversion processing by a conversion unit 102 and discrimination processing by a discrimination unit 74 of a client computer 7 in the reading data of the filled mark sheet.

Description

  The present invention relates to a mark detection device, and more particularly to a technique for detecting whether or not a mark is described on a document based on read data obtained by reading the document with the mark detection device.

  2. Description of the Related Art Conventionally, an OMR (Optical Mark Reading) apparatus is known as an apparatus for reading a mark written on a special document such as a mark sheet. This OMR apparatus detects whether or not there is a mark on the original document based on the reflected light irradiating the surface of the original document. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for shortening the reading time when reading a mark sheet by setting an appropriate resolution or the like according to the mark sheet when the mark sheet is read by an image forming apparatus.

JP 2002-354212 A

  In order to detect the presence or absence of a mark (marked or not) described in a document such as a mark sheet, the OMR device is necessary. Therefore, a person who performs the mark detection needs to purchase the OMR device. Since the purchase of the OMR device causes a cost burden, it is desirable to reduce the cost burden. Further, when a mark sheet is read by an image forming apparatus as disclosed in Patent Document 1, it is desired to further improve the mark reading accuracy. Furthermore, it is desirable that the operation required by the user at the time of mark detection is simple.

  The present invention has been made to solve the above problem, and can detect a mark on a document such as a mark sheet with high accuracy at a reduced cost compared to the conventional method without requiring a troublesome operation by the user. The purpose is to do.

The invention according to claim 1 of the present invention includes a reading unit that reads an image on a document,
Each portion of the image indicated by the read data read by the reading unit is compared with a predetermined standard pattern by OCR processing, and is matched with the corresponding standard pattern. A conversion unit that converts the character into
A plurality of character shape is similar to an image that approximates the solid black square images or which previously stored as the first reference characters, character converted by the conversion unit, is the first reference character In this case, it is determined that the image portion to be determined on the document is a mark, and the character after conversion by the conversion unit is not the first reference character, or conversion to a character by the conversion unit A determination unit that determines that the image portion that is the determination target on the document is not a mark,
A difference calculation unit that calculates a difference between read data of an unfilled mark sheet read as a document by the reading unit and read data of a filled mark sheet;
In the read data of the completed mark sheet, a region where the difference calculated by the difference calculation unit is larger than a predetermined value is detected, and the detected region is converted by the conversion unit. And an area determination unit for determining as a mark sheet area for performing determination processing by the determination unit,
The conversion unit and the determination unit are mark detection devices that perform the conversion process and the determination process on read data of the completed mark sheet, which is read data that is a mark sheet region determined by the region determination unit It is.

According to the present invention, the conversion unit converts the read data read by the reading unit into a character by OCR processing, and the determination unit determines whether the converted character is the first reference character. When it is determined that the image portion that is the determination target above is a mark and is not the first reference character or character conversion is not possible, the image portion that is the determination target on the document is It is determined that it is not a mark. Therefore, it is possible to determine the presence / absence of a mark on a document such as a mark sheet using a reading device such as an image forming apparatus capable of OCR processing without purchasing a special device for performing OMR processing.

  In addition, since character conversion by OCR processing is performed once and whether or not a mark is determined based on the converted character, whether or not the mark is detected directly from the shape of the image indicated by the read data is obtained. Can also improve accuracy. As a result, the mark can be detected with high accuracy using an image forming apparatus or the like that is generally provided in a workplace environment such as a company or an office, and it is not necessary to purchase an OMR apparatus. The mark can be detected at a low cost.

  Further, the difference calculation unit calculates a difference between the read data of the unfilled mark sheet read by the reading unit and the read data of the filled mark sheet, and the region determination unit calculates the difference in advance in the read data of the filled mark sheet. An area that is gathered with a value larger than a predetermined value is determined as a mark sheet area for performing conversion processing by the conversion unit and determination processing by the determination unit, and the conversion unit and the determination unit use the read data of the completed mark sheet. Therefore, the conversion process and the discrimination process are performed on the read data to be the mark sheet area.

  For this reason, even if the same document contains a region to be subjected to mark detection by the conversion process and the determination process and a region not to be subjected to the mark detection, the user can make a mark detection target. Without obtaining an operation for determining the region, it is possible to accurately extract the region targeted for the mark detection and perform the conversion process and the discrimination process only on the extracted region. This simplifies the operation required by the user when detecting a mark.

The invention according to claim 2 is the mark detection device according to claim 1, wherein the conversion unit and the determination unit convert the read data of the completed mark sheet that is the mark sheet region into the conversion data. Performing the process and the discrimination process,
The read data in the area other than the mark sheet area is processed with the contents designated in advance.

  According to the present invention, the read data to be the mark sheet area is subjected to the conversion process by the conversion section and the determination process by the determination section to obtain the determination result of the mark detection, and becomes an area other than the mark sheet area. For the read data, for example, the read data (bitmap format, JPEG format, TIFF format, etc.) simply obtained by reading by the reading unit is left as it is, or only the character conversion by the conversion unit is performed. Is possible. Therefore, it is possible to perform different processing on the read data depending on whether or not the mark sheet region is determined by the region determination unit.

  According to a third aspect of the present invention, in the mark detection device according to the first or second aspect, the difference calculation unit has a data amount out of read data of a plurality of documents read by the reading unit. The least read data is used as the read data for the blank mark sheet.

  According to this invention, the difference calculation unit uses the read data with the smallest data amount among the read data of the plurality of documents read by the reading unit as the read data of the unfilled mark sheet. There is no need to perform a special operation for causing the mark detection apparatus to recognize the image data of the unfilled mark sheet used for the calculation. For example, the user can determine the mark sheet area and make the mark sheet area a target for mark detection even if the reading unit reads the mark sheet at a time without distinguishing between the unfilled mark sheet and the filled mark sheet.

  According to the present invention, it is possible to accurately detect a mark on an original such as a mark sheet at a cost reduced as compared with the prior art without requiring a troublesome operation from the user.

It is sectional drawing which shows the mechanical structure of the multifunctional machine as an image reading apparatus which makes a part of mark detection apparatus. FIG. 2 is a functional block diagram schematically illustrating a main internal configuration of a multifunction peripheral. It is a flowchart which shows 1st Embodiment of the mark detection process by a mark detection apparatus. It is a figure which shows the example of the original surface. It is a figure which shows the example of the image of the mark printed on the original, and the image of the mark written in the said mark. It is a figure which shows the example of a mapping of the difference calculated by the difference calculation part. It is a figure which shows the example of the distribution map which shows distribution of the pixel with a large difference value. It is a figure which shows the example of total data. (A) is a figure which shows the example of the character group converted by the conversion part virtually, (B) is a figure which shows the example of numerical formula, (C) is a figure which shows the example of a total value string. It is a flowchart which shows 2nd Embodiment of the mark detection process by a mark detection apparatus. It is a flowchart which shows 3rd Embodiment of the mark detection process by a mark detection apparatus.

  Hereinafter, an image reading apparatus and a computer as a mark detection apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  A mark detection apparatus according to an embodiment of the present invention includes a partial configuration of an image reading apparatus and a partial configuration of a computer. FIG. 1 is a cross-sectional view showing a mechanical configuration of a multifunction machine as an image reading apparatus that forms part of the mark detection apparatus. The multifunction machine 1 has a plurality of functions such as a copy function, a printer function, a scanner function, and a facsimile function. The multi-function device 1 includes an apparatus main body 2 and a feeding device 3 disposed on the side of the apparatus main body 2 (left side in FIG. 1). The apparatus main body 2 includes a main body section 20, a manual feed tray 4, a document reading section (reading section) 5 disposed on the upper portion of the apparatus body 2, and a document feeding section disposed above the document reading section 5. (Reading unit, but not essential as a reading unit) 6.

  An operation unit 47 is provided at the front part of the multifunction machine 1. The operation unit 47 includes a start key 471, a numeric keypad 472, a display unit 473, a reset key 474, a stop key 475, and the like.

  The display unit 473 is a liquid crystal display including, for example, an LCD (Liquid Crystal Display) or the like that displays operation guide information and the like related to each of the functions provided in the multi-function device 1, and performs various settings necessary for using the functions. A touch panel function is provided to allow the user to input.

  The start key 471 is a key for the user to input a print execution instruction. The numeric keypad 472 is a key for inputting a numerical value such as the number of copies to be printed. The reset key 474 is a key for resetting the setting content set on the display unit 473. The stop key 475 is a key for stopping the printing operation being executed.

  The document reading unit 5 includes a scanner unit 51 including a CCD (Charge Coupled Device) and an image irradiation lamp, a document table 52 made of a transparent member such as glass, and a document reading slit 53. The scanner unit 51 is configured to be movable by a driving unit (not shown). When reading a document placed on the document table 52, the scanner unit 51 is moved along the document surface at a position facing the document table 52, and scans the document surface to acquire the image data of the document. It outputs to the main control part 100 mentioned later. Further, when reading a document fed by the document feeding unit 6, the scanner unit 51 is moved to a position facing the document reading slit 53, and is synchronized with the document feeding operation by the document feeding unit 6. Then, the original conveyed by the conveying operation is read through the original reading slit 53, and image data of the read original is output to the main control unit 100.

The document feeding unit 6 includes a document placing table 61 on which a document is placed, a document discharge unit 62 from which an image-read document is discharged, and a document transport mechanism 63. The document transport mechanism 63 includes a paper feed roller, a transport roller, and a paper reversing mechanism (not shown). The document transport mechanism 63 drives the paper feed roller and the transport roller to feed the documents placed on the document placing table 61 one by one to a position facing the document reading slit 53, and passes the document reading slit 53 through the document reading slit 53. Then, after reading from the scanner unit 51, the document is discharged to the document discharge unit 62. Further, the document transport mechanism 63 causes the paper reversing mechanism to reverse the document and to transport it again to a position facing the document reading slit 53, so that images on both sides of the document are scanned via the document reading slit 53. 51 can be read.

  Further, the document feeding unit 6 is provided so as to be rotatable with respect to the apparatus main body 2 so that the front side thereof can move upward. By moving the front side of the document feeder 6 upward to open the upper surface of the document table 52, the user can place a read document, for example, a book in a spread state, on the upper surface of the document table 52. ing.

  The apparatus main body 2 includes a plurality of paper feed cassettes 461 that store recording papers (an example of a recording medium) having different sizes, and paper feeds that feed the recording papers one by one from the paper feed cassette 461 and convey them to the image forming unit 40. A roller 462 and an image forming unit 40 that forms and outputs an image on a recording sheet conveyed from the paper feed cassette 461 are provided.

  The image forming unit 40 includes an image forming mechanism 12 and a fixing unit 45. The image forming mechanism 12 performs an image forming operation for forming a toner image on the recording paper P fed from the paper feed cassette 461, the feeding device 3, and the manual feed tray 4. The image forming mechanism 12 includes an intermediate transfer belt 125 and image forming units 12M, 12C, 12Y, and 12B for magenta, cyan, yellow, and black that are disposed adjacent to the intermediate transfer belt 125. And a drive roller 125a that causes the intermediate transfer belt 125 to travel unsupported, and a secondary transfer roller 41.

  Each of the image forming units 12M, 12C, 12Y, and 12B includes a photosensitive drum 121, a developing device 122, a toner cartridge (not shown), a charging device 123, an exposure device 124, and a primary transfer roller 126, respectively. And a drum cleaning device 127.

  The main control unit 100 drives and controls the image forming units 12M, 12C, 12Y, and 12B for each color at the time of executing a print job or the like, and magenta, cyan, yellow, and black toner on the surface of the intermediate transfer belt 125. The images are transferred so as to overlap each other, and a color toner image is formed on the surface of the intermediate transfer belt 125 (intermediate transfer (primary transfer)).

  The secondary transfer roller 41 transfers the color toner image formed on the surface of the intermediate transfer belt 125 onto the recording paper P conveyed from the paper conveyance unit 411. The toner image is fixed on the recording paper P to which the toner image is transferred by the fixing unit 45.

  The paper transport unit 411 includes a paper transport path L1, a paper reverse transport path L2, and transport rollers 463, 464, and 465. By driving the transport rollers 463 and 464 provided in the paper transport path L, the toner image is transferred. The stack tray 71 conveys the fixed recording paper to the discharge tray 48.

  When the image forming unit 40 forms an image on both sides of the recording paper and outputs the image, the paper transport unit 441 transfers the recording paper on which the image is formed on one side in the image forming unit 40 to the discharge tray 48 side. After being nipped by the transport roller 463, the recording paper is switched back by reversing the transport roller 463 and sent to the paper reverse feed path L 2 to be transported again to the upstream area of the image forming unit 40. As a result, the image forming unit 40 forms an image on the other side of the recording sheet.

  Next, the configuration of the multifunction machine 1 will be described. FIG. 2 is a functional block diagram schematically showing the main internal configuration of the multifunction machine 1.

  The multifunction machine 1 includes a control unit 10. The control unit 10 includes a CPU (Central Processing Unit), a RAM, a ROM, a dedicated hardware circuit, and the like, and controls the overall operation of the multifunction machine 1.

  The control unit 10 is connected to the document reading unit 5, image processing unit 31, image forming unit 40, operation unit 47, facsimile communication unit 92, HDD (hard disk drive) 81, and network interface unit 91.

  The control unit 10 includes a main control unit 100, a network control unit 101, a conversion unit 102, a difference calculation unit 103, and an area determination unit 104.

  The main control unit 100 governs overall operation control of the multifunction machine 1 described above. The main control unit 100 controls driving and processing of each mechanism unit necessary for executing operation control for each of the scanner function, printer function, copy function, and printer function.

  The network control unit 101 is in charge of control for performing network communication with an external device such as the client computer 7 through the LAN or the Internet. For example, the network control unit 101 transmits, from the network interface unit 91, data including a character group after conversion converted by the conversion unit 102 described later to the client computer 7 or the like.

  The conversion unit 102 compares each portion of the image indicated by the read data read by the document reading unit 5 with which of a plurality of predetermined standard patterns and corresponds to the determined standard pattern. Convert the attached character by OCR processing. For example, the conversion unit 102 stores a plurality of patterns indicating the images associated with the characters, symbols, and the like as the standard patterns in advance as images indicating characters such as characters and symbols. The conversion unit 102 uses the standard pattern as a template, collates each part of the image indicated by the read data read by the document reading unit 5 with whether or not the template matches the standard pattern, and compares the standard pattern. By examining the correlation corresponding to the pixel data level for each part, an image part that is the same as or close to the template is detected from the read data (pattern matching). The conversion unit 102 converts the image portion that is the same as or close to the template detected in this way into a character associated with the template.

The difference calculation unit 103 calculates the difference between the read data of the unfilled mark sheet read as a document by the document reading unit 5 and the read data of the filled mark sheet. Details of the difference calculation processing by the difference calculation unit 103 will be described later. Here, the mark sheet is a sheet on which a white square-shaped mark p is printed and a position on which the writer should write a mark is indicated by the mark p. The unfilled mark sheet is a mark sheet on the surface of which only the image printed on the sheet from the beginning, such as the above-mentioned mark p, has not been filled in by the writer. The completed mark sheet refers to a mark sheet in which a mark has already been entered by the writer in the white square mark p on the mark sheet. In addition, the mark refers to a mark that is entered by handwriting or the like of a person by painting or the like at a designated position indicated by printing on a mark sheet as a document. For example, when all or part of a document is a so-called mark sheet, a mark or the like written by a person with a writing instrument at a predetermined position on the mark sheet is the mark.

  The area determination unit 104 detects an area in which differences that are larger than a predetermined value among the differences calculated by the difference calculation unit 103 are present in the read data of the completed mark sheet, The detected area is determined as a mark sheet area for performing the conversion process by the conversion unit 102 and the determination process by the determination unit 74 of the client computer 7.

  Note that the conversion unit 102 performs the conversion process and the determination unit 74 performs the determination process on the read data of the completed mark sheet that is the mark sheet area determined by the area determination unit 104. .

  The scanner unit 51 of the document reading unit 5 includes an image irradiation lamp 511 and a CCD sensor 512. The scanner unit 51 irradiates the original with the image irradiation lamp 511 and receives the reflected light with the CCD sensor 512, thereby reading the image from the original.

  The image processing unit 31 performs image processing on the image data of the image read by the document reading unit 5 as necessary. For example, the image processing unit 31 performs predetermined image processing in order to improve the quality after the image read by the document reading unit 5 is formed by the image forming unit 40. The image processing unit 31 includes a correction unit 311 and an image processing unit 312. The correction unit 311 includes an output voltage of the charging device 123 as image output process data of the image forming unit 40, an exposure light amount of the exposure device 124, a developing bias voltage of the developing device 122, a transfer bias of the primary transfer roller 126, and a secondary transfer roller. 41, such as a transfer bias, is adjusted. For example, the image processing unit 312 performs predetermined correction processing such as level correction and gamma correction on the image data read by the document reading unit 5, or compression or expansion processing, and expansion or reduction processing of the image data Various processing processes such as are performed. The image data processed by the image processing unit 31 is stored in the image memory 35 or output to the image forming unit 40 or the facsimile communication unit 92.

  The image memory 35 stores image data read by the document reading unit 5.

  The paper transport unit 411 includes the paper feed cassette 461, the paper feed roller 462, the transport rollers 463, 464, 465, and the like shown in FIG. 1, and records the recording paper stored in the paper feed cassette 461 into the image forming unit 40. And is conveyed to the discharge tray 48.

  As described above, the image forming unit 40 includes the image forming units 12M, 12C, 12Y, and 12B, the intermediate transfer belt 125 stretched around the drive roller 125a, the secondary transfer roller 41, and the like. The image data to be image formed by the image forming unit 40 includes image data read by the document reading unit 5, image data transmitted from the client computer 7 in the local area via the LAN and network interface unit 91, and the like. Image data transmitted from the.

  The operation unit 47 includes a display unit 473 and the like, and accepts an instruction from the user about the multifunction device 1 by the touch panel function by the display unit 473 and each operation key group described above.

  The facsimile communication unit 92 includes an unillustrated encoding / decoding unit, modulation / demodulation unit, and NCU (Network Control Unit), and performs facsimile transmission using a public telephone network. For example, the facsimile communication unit 92 transmits image data of a document read by the document reading unit 5 to a facsimile device or the like via a telephone line, or receives image data transmitted from the facsimile device or the like.

  An HDD (Hard Disk Drive) 81 stores image data read by the document reading unit 5 and various data such as an output format set in the image data. The image data stored in the HDD 81 is used in the multifunction machine 1 and various programs employed therein.

  The network interface unit 91 includes a communication module such as a LAN board, and transmits / receives various data to / from the client computer 7 and the like via the LAN 5 connected to the network interface unit 91. For example, the network interface unit 91 transmits data including character groups converted by the conversion unit 102 to the client computer 7 via the network interface unit 91 and the LAN 5.

  The client computer 7 includes a network control unit 70, a main control unit 72, a display unit 73, a determination unit 74, a display control unit 75, a totaling unit 78, and an operation unit 701. The network control unit 70 controls data communication through the network. The main control unit 72 controls overall operation of the client computer 7. A control unit that includes a CPU, a RAM, a ROM, a dedicated hardware circuit, and the like and is provided in the client computer 7 may function as the network control unit 70 to the totaling unit 78, or the network control unit 70 to the totaling unit 78. Each may be configured separately by a circuit.

  The client computer 7 is an embodiment of a computer that forms part of the mark detection device.

…等の複数のキャラクターを第１の基準キャラクターとして予め記憶している。 For example, among the characters converted by the conversion unit 102, the determination unit 74 has a shape similar to a black-colored square image or an image similar thereto.

Are stored in advance as a first reference character.

  The determination unit 74 determines whether the character after the conversion by the conversion unit 102 of the multifunction device 1 is a predetermined first reference character, and if the character is the first reference character, When it is determined that the image portion corresponding to the character in the read data read by the document reading unit 5 of the multifunction device 1 is a mark, and the character after the conversion by the conversion unit 102 is not the first reference character Alternatively, when the conversion by the conversion unit 102 is impossible, it is determined that the image portion to be converted by the conversion unit 102 is not a mark.

  The display control unit 75 performs display control for causing the display unit 73 to perform display.

  The totaling unit 78 totals the determination results as to whether or not each portion of the image indicated by the read data read by the document reading unit 5 is the mark determined by the determination unit 74.

  The operation unit 701 includes, for example, a keyboard or a mouse pointer, and receives instructions from the user regarding operations and processes performed by the client computer 7.

  Next, a first embodiment of mark detection processing by the mark detection apparatus will be described. FIG. 3 is a flowchart showing a first embodiment of mark detection processing by the mark detection apparatus. FIG. 4 is a diagram showing an example of the document surface. FIG. 5 is a diagram illustrating an example of an image of a mark p printed on an original m and an image of a mark written in the mark p. FIG. 6 is a diagram illustrating a mapping example of the differences calculated by the difference calculation unit 103. FIG. 7 is a diagram illustrating an example of a distribution map indicating a distribution of pixels having a large difference value. FIG. 8 is a diagram illustrating an example of total data. 9A is a diagram virtually illustrating an example of a character group converted by the conversion unit, FIG. 9B is a diagram illustrating an example of a mathematical expression, and FIG. 9C is a diagram illustrating an example of a total value string. .

  A mark detection instruction for executing a mark detection process for detecting an image indicating a predetermined mark shape from an image indicated by read data read by the document reading portion 5 by an operation of the operation portion 47 by the user is provided on the operation portion. 47 (YES in S1), the main control unit 100 causes the display unit 473 to display a message prompting the original reading unit 5 to read an unfilled mark sheet as an original, and from the user, It waits for an unfilled sheet reading instruction to read an unfilled mark sheet to be input to the operation unit 47 (S2).

  When the user inputs an unfilled sheet reading instruction to the operation unit 47 and the main control unit 100 accepts the instruction (YES in S2), the main control unit 100 causes the document reading unit 5 to send a document placing table 61 at this time. Alternatively, the manuscript placed on the manuscript 52 is read as an unfilled mark sheet (S3).

  For example, as shown in FIG. 4, a white square mark p is printed on the surface of an unfilled mark sheet to be read, and the writer enters a mark with the mark p. The power position is shown.

  Subsequently, the main control unit 100 causes the display unit 473 to display a message prompting the original reading unit 5 to read the completed mark sheet as a document, and reads the completed mark sheet from the user. It waits for a completed sheet reading instruction to be input to the operation unit 47 (S4).

  When the user inputs the completed sheet reading instruction to the operation unit 47 and the main control unit 100 accepts the instruction (YES in S4), the main control unit 100 instructs the document reading unit 5 at this time to place the document placement table. The original placed on 61 or the original 52nd is read as a completed mark sheet (S5). When a plurality of documents are placed on the document placing table 61, the main control unit 100 causes the document reading unit 5 to read all the documents.

  For example, on the surface of the mark sheet on which the reading is completed, a mark written by the writer writing the mark with a writing tool or the like is written in an area surrounded by the mark p. The mark mk, which is a black-colored square image in which all of the inside of the square shape indicating the mark p and the mark p is filled or an image similar thereto, has a shape shown in FIG. When the document reading unit 5 reads the mark sheet with the mark written thereon as a document, the image of the mark p (the mark unfilled portion), the image of the mark mk written in the mark p, and further Reads various characters or figures written on the mark sheet.

  The mark detection instruction in S1, the unfilled sheet reading instruction in S2, and the filled sheet reading instruction in S4 are input to the client computer 7 by the operation of the operation unit 701 of the client computer 7 by the user, and network control is performed. The unit 70 outputs the mark detection instruction to the multifunction device 1 side, the network control unit 101 of the multifunction device 1 receives the instructions, and the main control unit 100 performs the processes described above according to the instructions. Also good.

  Then, the difference calculation unit 103 calculates the difference between the read data of the unfilled mark sheet obtained in S3 and the read data of the filled mark sheet obtained in S5 (S6). For example, the difference calculation unit 103 compares the image indicated by the read data of the unfilled mark sheet obtained in S3 with the image indicated by the read data of the completed mark sheet obtained in S5 at the pixel value level. A difference between pixel values of pixels at the same position in the areas of both images is calculated, and a mapping is created in which the difference between the pixel values of each pixel is arranged according to the position of each pixel. In the case where there are a plurality of mark sheets read in S5, the difference calculating unit 103 uses the difference written in the plurality of completed entries obtained in S5 for the image indicated by the read data of the unfilled mark sheet obtained in S3. Each of the images indicated by the read data on the mark sheet is compared and calculated in units of pixels, and for each pixel position constituting the image indicated by the read data, each pixel of the image indicated by the read data on all completed mark sheets is calculated. The difference average value is calculated, and the mapping is formed using the difference average value. An example of mapping created using the difference average value is shown in FIG.

  Thereafter, the area determination unit 104 determines a mark sheet area based on the difference between the read data of the unfilled mark sheet and the filled mark sheet calculated by the difference calculation unit 103 in S6 (S7). In other words, the area determination unit 104 detects an area in which differences that are larger than a predetermined value among the differences calculated by the difference calculation unit 103 are present in the read data of the completed mark sheet. . For example, the region determination unit 104 uses the above mapping (FIG. 6) created by the difference calculation unit 103, and the difference is a predetermined value (for example, 20 in the case of a pixel value in 255 levels. A pixel having a larger value than that (which is not intended to be limited) and the position of the pixel are determined, and a distribution map indicating the distribution of pixels in which the difference is large in the read data of the completed mark sheet is created. An example of the distribution map is shown in FIG. Note that FIG. 7 shows a display on a larger scale than FIG.

  Further, the region determination unit 104 detects a region in which the pixels having a value larger than the predetermined value are concentrated and distributed in the read data of the completed mark sheet. For example, the region determination unit 104 uses the distribution map shown in FIG. 7 as an example, and in the image region indicated by the read data of the completed mark sheet, the pixel corresponding to the image assumed to be the mark mk (the difference is There are many pixels that have a value larger than a predetermined value), and the distribution density of the pixel is higher than a predetermined density (for example, 50%) for each region of a predetermined unit area. All regions that are determined are determined, and a region including all the determined regions is determined as a mark sheet region a1 for performing the conversion process by the conversion unit 102 and the determination process by the determination unit 74.

  According to such determination of the mark sheet area, the mark entered by the writer on the mark sheet m is extracted from the image read by the document reading unit 5 as a set of pixels in which the difference is large, and the difference Since the region where the distribution density of the pixels having a large value is high is determined as the mark sheet region a1, an image that has been changed by being filled in by the writer, that is, a region where an image showing the mark written by the writer exists is the mark sheet. It will be extracted as a region.

  Then, the conversion unit 102 performs character conversion by the above-described OCR processing on the mark sheet region portion in the image indicated by the read data of the completed mark sheet read by the document reading unit 5 in S5 (S8). For example, the conversion unit 102 performs the conversion process to the character by the above-described OCR process using the standard pattern as a template for each part of the mark sheet region. Here, the mark sheet area portion in the image indicated by the read data includes the image of the mark p and the image of the mark mk written in the mark p. Convert mk image to character.

…等のキャラクターに変換される。 Here, as shown in FIG. 5, the mark mk is a square-shaped black image or an image similar thereto, so that the mark mk is a black-colored square image by the OCR processing of the conversion unit 102. Or the shape is similar to this approximate image

It is converted into a character such as ...

…等のキャラクターに変換される。 On the other hand, a white square mark p whose shape is not filled in by the writer and whose shape is shown in FIG. Similar in shape to the image

It is converted into a character such as ...

  It should be noted that the conversion unit 102 converts the black solid color image or a character similar in shape to an image similar thereto, or a white square image or a character similar in shape to an image similar thereto. For the image portion that cannot be converted, the conversion unit 102 stores information indicating that the conversion is impossible as the conversion result.

  After that, the network control unit 101 sends the character group converted for the mark sheet area by the conversion unit 102 in S8 to the client computer 7 for performing the discrimination process and the totalization process to be described later from the network interface unit 91. Data consisting of information indicating that the conversion is impossible is transmitted (S9).

  In the client computer 7, when the network control unit 70 receives data including the converted character group via the network interface unit (not shown) (SS 1), the determination unit 74 determines that the converted character is the above-described character. Whether or not it is the first reference character (SS2), and if the character is the first reference character (YES in SS2), in the image indicated by the read data read by the document reading unit 5, It is determined that the image portion corresponding to the character is the mark mk entered by the writer (SS3). In addition, when the converted character is not the first reference character, or the information indicating that the character conversion by the conversion unit 102 is impossible (NO in SS2), the determination unit 74 reads the document. In the image indicated by the read data of the filled client read by the section 5, it is determined that the image or the image corresponding to the information is not the mark mk written by the writer (SS5). .

  That is, the conversion by the conversion unit 102 is simply to perform OCR processing on the read image data of the original. In the determination unit 74, the character converted by the OCR processing is entered as described above. It is determined whether or not the image representing the mark mk is a converted character.

…等のキャラクターが予め選定され、当該選定された複数のキャラクターが第１の基準キャラクターとして判別部７４に予め記憶されている。なお、上記マークが記入されず白抜き正方形状の印ｐを示す画像又はこれに近似する画像は、変換部１０２により、当該白抜き正方形状の画像に近似する

…等のキャラクターに変換されると想定されるため、第１の基準キャラクターとしては、少なくとも、これらのキャラクターは除外したものが記憶されることが望ましい。 For example, as the first reference character, the shape resembles a black-colored square image indicating the written mark mk or an image similar thereto.

.. Are selected in advance, and the plurality of selected characters are stored in advance in the determination unit 74 as the first reference character. Note that an image showing the white square mark p without being marked with the mark or an image similar thereto is approximated to the white square image by the conversion unit 102.

Since it is assumed that the character is converted into a character such as..., It is desirable to store at least those characters excluding these characters as the first reference character.

  Thereby, when a certain image described on the original is read by the original reading unit 5 and converted into any character by the conversion unit 102, the determination unit 74 determines that the converted character is the first character. By determining that the read image is the mark mk when it corresponds to the character, it can be accurately identified that the mark mk exists on the document.

  As described above, all of the mark sheet areas in the image indicated by the read data of the completed mark sheets read by the document reading unit 5 (if there are a plurality of read mark sheets that have been entered) are displayed. When the character conversion and determination are performed for the portion, the totaling is performed by the totaling unit 78 (SS4). Then, a series of processing as the mark detection processing ends (END).

  For example, as shown in FIG. 4, when five marks p are printed on the original m for each question, and the mark mk is written by one of the five marks p by the writer, The totaling unit 78 uses the determination result for each document determined by the determination unit 74, for each question (Q1, Q2, Q3,... In FIG. 4) of the plurality of documents. The number of marks mk written in each of the first marks p is calculated, and for example, total data as shown in FIG. 8 is created.

  When performing such totalization, the totaling unit 78 indicates whether or not the mark mk is indicated by each determination result for each document determined by the determination unit 74 and the mark mk corresponding to each determination result. Marks marked on each of the first to fifth marks p for each question (Q1, Q2, Q3,... In FIG. 4) using information indicating the position of the mark p. The number of mk is calculated and the total data shown in FIG. 8 is created. For example, it is assumed that an unillustrated timing mark is printed with black ink or the like in the vicinity of each question (Q1, Q2, Q3,... In FIG. 4) on a document as a mark sheet. In this case, the conversion unit 102 detects the image of the timing mark from the image indicated by the read data for each document when character-converting each portion of the image indicated by the read data for each document, and detects the detected timing. Based on the mark, the position information of the mark mk or the mark p is acquired for each question. The timing mark is detected by the conversion unit 102, for example, in the same manner as the pattern matching described above.

…等のキャラクター群に該当しない注目キャラクターであるかを順次検出して、当該注目キャラクターが検出された印ｐが何番目であるかを検出し、当該検出した何番目であるかの情報を判別結果とする数式を用いる。なお、当該数式の例は、図９(Ｂ)に示している。集計部７８は、当該注目キャラクターが検出された印ｐが何番目であるかを示す当該判別部７４による判別結果を各問毎に区分けし、各原稿のデータ毎に整列させた集計値列を作成する(図９(Ｃ))。 In addition to the above, the following can be used as the total. For example, when the network control unit 70 receives the character group indicated by the data converted by the conversion unit 102, the determination unit 74 classifies the data indicating the character group for each question and arranges the data for each document data. (FIG. 9A). The discriminating unit 74 and the totaling unit 78 calculate the total value sequence shown in FIG. In this case, the discriminating unit 74 approximates the white square image with respect to the first to fifth marks p included in the question, for example, for each question of each document as the above formula. Do

It is sequentially detected whether it is an attention character that does not correspond to the character group such as ..., detects the number p of the mark p where the attention character is detected, and discriminates information about the detected number Use the resulting formula. An example of the mathematical formula is shown in FIG. The totaling unit 78 classifies the determination result by the determination unit 74 indicating the number of the mark p from which the character of interest is detected, for each question, and generates a total value string arranged for each data of each document. It is created (FIG. 9C).

  According to the mark detection process performed by the multifunction device 1, the user can use a reading device provided in an image forming apparatus or the like that can perform OCR processing without purchasing a special device that can perform OMR processing. Mark on the original can be detected. As a result, the mark can be accurately detected using an image forming apparatus or the like that is generally provided in a workplace environment such as a company or an office. Therefore, it is not necessary to purchase an OMR apparatus. The mark can be detected at a reduced cost.

  In addition, since character conversion is once performed by OCR processing, and it is determined whether or not the mark is based on the converted character, it is more than the case of detecting whether or not the mark is directly from the shape of the image indicated by the read data. Mark detection accuracy can be improved. When determining whether or not the mark is directly from the shape of the image indicated by the scanned data, simply scan the document as a stain or the like, or delete part of the image that needs to be scanned. However, in the present invention, since it is determined whether or not the mark is based on the character after the character conversion by the OCR conversion once, the reading ability of the reading unit is changed. A decrease in mark detection accuracy is suppressed.

In addition, by performing the determination process of the mark sheet region, a single mark sheet (filled mark sheet) includes a region that is a target of mark detection by the conversion processing and a determination process, and a region that is not a target of the mark detection. Even if there is a mixture of these, without requiring the user to determine the target area for mark detection, the target area for mark detection is accurately extracted, and only the extracted area is converted. And a discrimination process can be performed. This simplifies the operation required of the user when detecting the mark. For example, instead of the mark sheet m shown in FIG. 4, a questionnaire in which a question sentence portion made up of characters and the like and a mark entry column (for example, a plurality of the above marks p arranged) as an answer to the question are printed alternately Even when the answer sheet is read as a manuscript, the target area for mark detection is accurately extracted, and only the extracted area is converted and discriminated without the problem portion being subject to mark detection. Can be performed.

…等のキャラクターを記憶しており、変換部１０２により変換されたキャラクターが当該第１の基準キャラクターである場合に、原稿読取部５によって読み取られた読取データの示す画像のうち当該キャラクターに該当する部分が、マークｍｋであると判別するが、これに代えて、判別部７４は、白抜き正方形状の画像に近似する

…等の予め選定されて記憶しているキャラクター群に該当しないキャラクターを、上記第１の基準キャラクターとし、上記マークか否かの判別に用いるようにしてもよい。 In the mark detection process, the discriminating unit 74 has a shape similar to a black-colored square image indicating the written mark mk or an image similar thereto as the first reference character.

.. Are stored, and when the character converted by the conversion unit 102 is the first reference character, it corresponds to the character in the image indicated by the read data read by the document reading unit 5 It is determined that the portion is the mark mk, but instead, the determination unit 74 approximates an image with a white square shape.

A character that does not correspond to the previously selected and stored character group such as... May be used as the first reference character and used to determine whether the character is the mark.

In the mark detection, the conversion unit 102 uses a character similar in shape to the black-colored square image or an image similar thereto, or a white square image or an image similar thereto. For the image portion that cannot be converted into any of the characters, the conversion unit 102 stores information indicating that the conversion is impossible as the conversion result. When none of the conversions is possible as described above, information indicating that the conversion is impossible is not stored as the conversion result, and the conversion unit 102 causes the black-colored square image to be stored. Or a character that has a similar shape to an image that approximates this, or a character that has been converted to a character that has a shape that is similar to a white square image or an image that approximates this May to transmit ter group from the network controller 101 or the like to the client computer 7. In this case, the determination unit 74 performs the determination process for the transmitted character group (SS2 to SS5). The same applies to second and third embodiments described later.

  Next, a second embodiment of mark detection processing by the mark detection apparatus will be described. FIG. 10 is a flowchart showing a second embodiment of mark detection processing by the mark detection apparatus. Note that the description of the same processing as that of the first embodiment described above will be omitted.

  In the second embodiment, for the mark sheet region in the image indicated by the read data of the completed mark sheet read by the document reading unit 5, the conversion process by the conversion unit 102 of the multifunction device 1 and the determination by the client computer 7 are performed. The above-described determination processing by the unit 74 is performed, but processing with contents specified in advance is performed in an area other than the mark sheet area.

  In the second embodiment, when the mark sheet area is determined by the area determination unit 104 (S17), the entire area of the image indicated by the read data of the completed mark sheet obtained by reading by the document reading unit 5 in S14 is determined. Then, the conversion unit 102 performs the conversion process by the OCR process (S18). Thereafter, the network control unit 101 targets the client computer 7 from the network interface unit 91 to the information indicating the mark sheet area determined in S17 and the entire area of the image indicated by the read data of the completed mark sheet in S18. Data including the converted character group and information indicating that the conversion is impossible is transmitted (S19).

  In the client computer 7, when the network control unit 70 receives the data including the converted character group and the information indicating that the conversion is impossible via the network interface unit (not shown), the determination is made (SS11). In accordance with the received information indicating the mark sheet area, the unit 74 applies the first character only to the mark sheet area among the data including the converted character group and the information indicating that the conversion is impossible. It is determined whether or not the character is a reference character (SS12). If the character is the first reference character (YES in SS12), the determination unit 74 determines that the image portion corresponding to the character is the mark mk (SS13), and the converted character is the first character. If the character is not the reference character or information indicating that the character conversion by the conversion unit 102 is not possible (NO in SS12), the read data of the client read by the document reading unit 5 indicates In the image, it is determined that the character that is not the first reference character or the image portion corresponding to the information is not the mark mk entered by the writer (SS15).

  As described above, regarding the mark sheet region in the image indicated by the read data of the completed mark sheet read by the document reading unit 5 (if there are a plurality of read mark sheets that have been read), The totaling unit 78 performs the totalization on the result of the character conversion and determination (SS14). Then, a series of processing as the mark detection processing ends (END). However, the totaling unit 78 does not perform the totaling for areas other than the mark sheet area, and outputs the data including the character group indicated by the conversion result in S18 and the information indicating that the conversion is impossible. Use a possible data format.

  In the above description, in S18, the conversion unit 102 performs the conversion process on the entire area of the image indicated by the read data of the completed mark sheet obtained by reading by the document reading unit 5 in S14. Instead, the conversion unit 102 performs the conversion process on the mark sheet area of the image indicated by the read data of the completed mark sheet, and the area other than the mark sheet area is read by the document reading unit 5 and the conversion is performed. Image data in a bitmap format, JPEG format, TIFF format, or the like that is not converted by the unit 102 may be used. In this case, the network control unit 101 causes the client computer 7 to transmit data including the character group converted for the mark sheet area of the image indicated by the read data of the completed mark sheet and information indicating that the conversion is impossible. And image data of an area other than the mark sheet area are transmitted (S19). In the client computer 7, the determination unit 74 detects whether or not the mark is a target of data including a character group converted for the mark sheet area and information indicating that the conversion is impossible. A discrimination process is performed (SS12). Then, the totaling unit 78 performs the above-mentioned totaling only for the determination result for the mark sheet area, and does not perform the totaling for the image data other than the mark sheet area, so that the data format can be output as it is.

  According to the second embodiment, only the read data to be the mark sheet area is subjected to the conversion process by the conversion unit 102 of the multifunction device 1 and the determination process by the determination unit 74 of the client computer 7 to determine the mark detection. For example, read data (bitmap format, JPEG format, TIFF format, etc.) obtained by reading by the document reading unit 5 may be left as it is for the read data that is an area other than the mark sheet area. Only the character conversion by the OCR process by the conversion unit 102 can be performed. For this reason, depending on whether or not the mark sheet region is determined by the region determination unit 104, different processing is performed on the read data to increase the possibility that the data obtained by the mark detection device is effectively used. Can do.

  Next, a third embodiment of mark detection processing by the mark detection apparatus will be described. FIG. 11 is a flowchart showing a third embodiment of mark detection processing by the mark detection apparatus. Note that the description of the same processing as in the first or second embodiment described above will be omitted. In the third embodiment, the processing in the client computer 7 is the same as that in the first and second embodiments, and thus illustration is omitted.

  In the third embodiment, the difference calculation unit 103 of the multifunction device 1 uses the read data with the smallest data amount among the read data of the plurality of originals read by the original reading unit 5 as the read data of the blank mark sheet. Use.

In the third embodiment, as shown in FIG. 11, when a mark detection instruction is input to the operation unit 47 by the user (YES in S21), the main control unit 100 causes the document reading unit 5 to place a document at this time. All mark sheets (documents) placed on the table 61 or the document 52 are read (S22).

  Here, the difference calculation unit 103 calculates the data amount of each mark sheet read data from the mark sheet read data read by the document reading unit 5 in S22 (S23). Then, based on the data amount of the read data of each mark sheet calculated in S23, the difference calculation unit 103 determines the read data that minimizes the data amount, and the determined read data is read data of the unfilled mark sheet. (S24).

  The difference calculation unit 103 calculates the difference between the read data stored as the read data of the unfilled mark sheet in the difference calculation process between the image indicated by the read data of the unfilled mark sheet and the image indicated by the read data of the filled mark sheet. Used as read data of unfilled mark sheet used for calculation.

  After the process of S24, a mark sheet area determination process corresponding to S6 to S9 in the first embodiment or S16 to S19 in the second embodiment is executed (S25).

  In this embodiment, the mark entry by the user is not performed, the number of images read by the document reading unit 5 is small, and the read data of the unfilled mark sheet that is assumed to have the smallest amount of read data by the document reading unit 5 Can be accurately extracted and used in the difference calculation process by the difference calculation unit 103. Therefore, the user needs to perform a special operation (for example, the processing of S2 and S3 shown in FIG. 3) for causing the mark detection apparatus to recognize the image data of the unfilled mark sheet used for calculating the difference. Absent. For example, the user can determine the mark sheet area and perform mark detection for the mark sheet area even if the original reading unit 5 reads the mark sheet area and the completed mark sheet at a time without distinguishing them.

  The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. For example, in the above-described embodiment, the mark detection apparatus according to an embodiment of the present invention is described as including a partial configuration of the multifunction machine 1 as an image reading apparatus and a partial configuration of the client computer 7. However, the mark detection apparatus according to the present invention is not limited to this. For example, as the image reading device, a device capable of reading an image on a document such as a scanner device may be used instead of the multifunction machine 1. In the above embodiment, the mark detection apparatus includes a partial configuration of the multi-function device 1 and a partial configuration of the client computer 7. The mark detection device may be configured only by the image forming apparatus such as the multifunction machine 1.

  The configurations and processes shown in the above embodiments using FIGS. 1 to 11 are only one embodiment of the present invention, and the present invention is not limited to the configurations and processes.

1 MFP 5 Document Reading Unit 6 Document Feeding Unit 61 Document Placement Table 10 Control Unit 100 Main Control Unit 102 Conversion Unit 103 Difference Calculation Unit 104 Area Determination Unit 7 Client Computer 72 Main Control Unit 74 Discrimination Unit 78 Totaling Unit

Claims (3)

A reading unit for reading an image on a document;
Each portion of the image indicated by the read data read by the reading unit is compared with a predetermined standard pattern by OCR processing, and is matched with the corresponding standard pattern. A conversion unit that converts the character into
A plurality of character shape is similar to an image that approximates the solid black square images or which previously stored as the first reference characters, character converted by the conversion unit, is the first reference character In this case, it is determined that the image portion to be determined on the document is a mark, and the character after conversion by the conversion unit is not the first reference character, or conversion to a character by the conversion unit A determination unit that determines that the image portion that is the determination target on the document is not a mark,
A difference calculation unit that calculates a difference between read data of an unfilled mark sheet read as a document by the reading unit and read data of a filled mark sheet;
In the read data of the completed mark sheet, a region where the difference calculated by the difference calculation unit is larger than a predetermined value is detected, and the detected region is converted by the conversion unit. And an area determination unit for determining as a mark sheet area for performing determination processing by the determination unit,
The conversion unit and the determination unit are mark detection devices that perform the conversion process and the determination process on read data of the completed mark sheet, which is read data that is a mark sheet region determined by the region determination unit . The conversion unit and the determination unit perform the conversion process and the determination process on the read data of the completed mark sheet to be the mark sheet region,
The mark detection apparatus according to claim 1, wherein the read data in an area other than the mark sheet area is processed with a predetermined content. The difference calculation unit includes a plurality of document reading data read by the reading unit,
The mark detection apparatus according to claim 1, wherein the read data having the smallest data amount is used as read data for the unfilled mark sheet.

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