JP2012133680A - Mark sensing card reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for processing a mark sensing card printed in various dropout colors at high speed.SOLUTION: A mark sensing card reader 10 includes: an image data acquisition part 12 for acquiring image data of a mark sensing card; a dropout color identification part 13 for identifying dropout colors from detected identification codes, by detecting the identification codes for identifying the dropout colors of the mark sensing card printed in an identification code region provided on at least one of the leading end and the trailing end of the mark sensing card from the image data acquired by the image data acquisition part 12; a mark detection part 18 for detecting the presence or absence of marks entered into the mark sensing card from a dropped-out image data on which a data of a part of the mark sensing card printed by the dropout colors identified by the dropout color identification part 13 is removed.

Description

  The present invention relates to a mark sheet reading apparatus, and more particularly to a mark sheet reading apparatus that processes mark sheets printed in various dropout colors.

In the field of mark sheet readers that detect the presence or absence of marks entered on a mark sheet, mark sheet readers that use dropout colors are widely used.
Information printed on the mark sheet in dropout color is removed from the image data before the process of detecting the presence or absence of a mark. For this reason, the dropout color is used to print information unnecessary for processing for detecting the presence / absence of a mark, such as a frame indicating a mark entry location and other items to be transmitted to a person, on a mark sheet.

  As a dropout color used for a mark sheet, conventionally, for example, a limited color such as an orange color has been used. However, in recent years, various colors have been used as the dropout color in response to a request to use a color that is easier for humans to visually recognize as the dropout color. For this reason, there are presently mark sheets printed in various dropout colors.

  However, currently used mark sheet readers are only compatible with a predetermined single dropout color depending on the wavelength of the light source, the wavelength characteristics of the color filter, and the like (hereinafter referred to as the SDOC type mark sheet reader). ), And can only deal with mark sheets printed in a specific dropout color.

  In view of this situation, a mark sheet reading apparatus (hereinafter referred to as MDOC type mark sheet reading apparatus) that supports a plurality of dropout colors has been proposed in recent years, and it can handle mark sheets printed in various dropout colors. Is underway.

JP-A-5-22498 JP 2004-227254 A JP 2006-65519 A

  By the way, in the SDOC type mark sheet reading device, when the image data of the mark sheet is acquired by an image sensor or the like, the data of the mark sheet portion already printed in the dropout color is removed from the image data.

  On the other hand, the MDOC type mark sheet reading apparatus currently proposed identifies the dropout color used in the mark sheet by analyzing the image data of the mark sheet, and then the portion of the portion printed in the dropout color. Remove the data from the mark sheet image data.

  For this reason, the MDOC type mark sheet reading apparatus is compared with the SDOC type mark sheet reading apparatus in a series of processes from reading a mark sheet to detecting the presence or absence of a mark (hereinafter, this series of processes will be collectively referred to as mark sheet processing). , Will take more time.

  In view of such circumstances, an object of the present invention is to provide a technique for processing a mark sheet printed in various dropout colors at high speed.

  According to one aspect of the present invention, an image data acquisition unit that acquires image data of a mark sheet, and an image data acquired by the image data acquisition unit are provided in an identification code area provided at at least one of the front end and the rear end of the mark sheet. A dropout color identifying unit for detecting an identification code for identifying a dropout color of a printed mark sheet and identifying a dropout color from the detected identification code, and a dropout identified by the dropout color identifying unit Provided is a mark sheet reading device including a mark detection unit for detecting presence / absence of a mark written on a mark sheet from image data after dropout from which data of a mark sheet printed in color is removed.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which processes the mark sheet printed by various dropout colors at high speed can be provided.

1 is a schematic configuration diagram of a mark sheet reading apparatus according to Embodiment 1. FIG. It is the figure which illustrated the mark sheet used with the mark sheet reading apparatus illustrated in FIG. FIG. 2 is a functional block diagram of the mark sheet reading apparatus exemplified in FIG. 1. 3 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. 1. FIG. 2 is a diagram illustrating a correspondence relationship between an identification code and a dropout color used in the mark sheet reading device illustrated in FIG. 1. 6 is a functional block diagram of a mark sheet reading apparatus according to Embodiment 2. FIG. 7 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. 6. 6 is a schematic configuration diagram of a mark sheet reading apparatus according to Embodiment 3. FIG. FIG. 9 is a functional block diagram of the mark sheet reading apparatus exemplified in FIG. 8. 9 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. 8.

  The mark sheet reading apparatus according to each embodiment of the present invention is printed with various dropout colors by identifying the dropout color of the mark sheet from the identification code for identifying the dropout color printed on the mark sheet. This is a mark sheet reading device that processes a mark sheet at high speed.

  Hereinafter, each embodiment will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a mark sheet reading apparatus according to the present embodiment. FIG. 2 is a diagram illustrating a mark sheet used in the mark sheet reading apparatus illustrated in FIG. The configuration of the mark sheet reading device 10 according to the present embodiment and the mark sheet 20 used in the mark sheet reading device 10 will be outlined with reference to FIGS.

  As illustrated in FIG. 1, the mark sheet reading device 10 includes an imaging device 30 that images the mark sheet 20 and generates image data of the mark sheet 20, and an image processing device 40 that detects the presence or absence of a mark from the image data. Contains.

  The imaging device 30 includes a light source 31 that emits illumination light composed of light of a plurality of wavelengths, and a color sensor 32 that generates RGB multilevel image data of the mark sheet 20. The color sensor 32 further includes a line sensor 32a that detects a red (R) wavelength, a line sensor 32b that detects a green (G) wavelength, and a line sensor 32c that detects a blue (B) wavelength. It is out. The image processing device 40 includes an image memory 41 that stores image data of the mark sheet 20 generated by the imaging device 30.

  As illustrated in FIG. 2, the mark sheet 20 used in the mark sheet reading apparatus 10 includes identification code areas (an identification code area 21 a and an identification code area 21 b) provided at the front and rear ends of the mark sheet 20, and marks. And a mark entry area 22 for entry. In the identification code area 21a and the identification code area 21b, an identification code for identifying the dropout color of the mark sheet 20 is printed.

  The identification code area 21a is used when the mark sheet 20 is inserted into the imaging device 30 from the leading end side (identification code area 21a side) along the sheet feeding direction. On the other hand, the identification code area 21b is used when the mark sheet 20 is inserted into the imaging device 30 from the rear end side (identification code area 21b side) along the sheet feeding direction. In this embodiment, the case where the identification code areas are provided at the front and rear ends of the mark sheet will be described. However, the present invention is not limited to this, and the identification code areas may be provided at either the front or rear end of the mark sheet. In that case, it inserts in the imaging device 30 from the edge part in which the identification code area is printed.

FIG. 3 is a functional block diagram of the mark sheet reading apparatus illustrated in FIG. The functional configuration of the mark sheet reading apparatus 10 will be outlined with reference mainly to FIG.
The imaging device 30 emits illumination light composed of light of a plurality of wavelengths to illuminate the mark sheet 20, and image data for acquiring RGB multivalued image data from the reflected light of the mark sheet 20 by the light of the illumination unit 11 An acquisition unit 12, a dropout color identification unit 13 for identifying a dropout color of the mark sheet 20, a dropout processing unit 14 for generating RGB multivalued image data from which data of a color corresponding to the dropout color is removed, A monochromatic unit 15 for converting RGB multilevel image data into monochromatic multilevel image data. The illumination unit 11 corresponds to the light source 31 illustrated in FIG. 1, and the image data acquisition unit 12 corresponds to the color sensor 32 illustrated in FIG.

  The image processing apparatus 40 includes a storage unit 16 that stores single-color multivalued image data, a binarization unit 17 that binarizes the single-color multivalued image data to generate binary image data, and binary image data. And a mark detection unit 18 for detecting the presence or absence of a mark entered on the mark sheet 20. The storage unit 16 corresponds to the image memory 41 illustrated in FIG.

  FIG. 4 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. FIG. 5 is a diagram illustrating the correspondence between the identification code and the dropout color used in the mark sheet reading apparatus illustrated in FIG. A method of processing the mark sheet 20 by the mark sheet reading apparatus 10 will be specifically described mainly with reference to FIGS. Hereinafter, a case where the mark sheet 20 is inserted into the imaging device 30 along the arrow illustrated in FIG. 2 will be described as an example.

  In step S101, when the mark sheet 20 is inserted into the imaging device 30 and processing by the mark sheet reading device 10 is started, the illumination unit 11 emits illumination light to illuminate the inserted mark sheet 20, and light from the illumination unit 11 is emitted. The image data acquisition unit 12 acquires the RGB multi-value image data of the mark sheet 20 from the reflected light of the mark sheet 20.

  In step S102, the dropout color identification unit 13 uses an identification code for identifying the dropout color of the mark sheet 20 printed in the identification code area 21a from the RGB multivalued image data acquired by the image data acquisition unit 12. To detect. Then, the dropout color of the inserted mark sheet 20 is identified from the detected identification code.

  More specifically, the imaging device 30 has a table (hereinafter referred to as a DOC table) in which the correspondence between the identification code and the dropout color is defined as illustrated in FIG. The out-color identification unit 13 detects an identification code that matches the pattern described in the column of the identification code symbol of the DOC table 19 from the identification code area 21a. Thereafter, the dropout color identification unit 13 identifies the dropout color of the mark sheet 20 by acquiring an identification code number corresponding to the detected identification code from the DOC table 19.

  In step S <b> 103, the dropout processing unit 14 removes color data corresponding to the dropout color identified by the dropout color identification unit 13 from the RGB multivalued image data acquired by the image data acquisition unit 12. Thereby, the dropout processing unit 14 generates the RGB multi-valued image data that has been dropped out from which the data of the portion of the mark sheet 20 printed in the dropout color has been removed.

  More specifically, the dropout processing unit 14 outputs three lines of image data from the color sensor 32, that is, one line of R multilevel image data output from the line sensor 32a, and the line sensor 32b. Every time RGB multi-value image data for one line and RGB multi-value image data for one line output from the line sensor 32c are output, dropout color is generated from the RGB image data. Remove the color data corresponding to.

  In step S <b> 104, the monochromatic unit 15 converts the RGB multi-valued image data that has been dropped out generated by the drop-out processing unit 14 into single-color multi-valued image data that has been dropped out, and outputs the data to the image processing device 40. .

  More specifically, the monochromator 15 averages the R multivalued image data, the G multivalued image data, and the B multivalued image data of the RGB multivalued image data output from the dropout processing unit 14. Thus, single-color multivalued image data is generated.

In step S <b> 105, the storage unit 16 stores the single color multi-valued image data that has been dropped out and is output from the monochromatic unit 15.
In step S106, the binarization unit 17 binarizes the single color multi-valued image data that has been dropped out and stored in the storage unit 16, and generates binary image data that has been dropped out.

  More specifically, the binarization unit 17 analyzes the single-color multivalued image data and determines a threshold value, and then binarizes the single-color multivalued image data using the threshold value as a reference. For this reason, the binarization unit 17 executes binarization processing after monochrome single-valued image data of the entire mark entry area 22 of the mark sheet 20 is output to the storage unit 16 in order to calculate an appropriate threshold value. .

  Finally, in step S107, the mark detection unit 18 detects the presence / absence of a mark written on the mark sheet 20 from the binary image data that has been dropped out and generated by the binarization unit 17.

  Note that the processing from step S101 to step S105 is started as soon as the output from the preceding step is received. That is, it is executed as a real-time process substantially. On the other hand, the processing of step S106 and step S107 is started after the image data of the entire mark entry area 22 is generated. That is, it is executed as non-real time processing.

  The mark sheet reading apparatus 10 identifies the dropout color from the identification code printed in the identification code area of the mark sheet 20 using a correspondence table such as the DOC table 19 illustrated in FIG. For this reason, the mark sheet reading apparatus 10 can identify the dropout color at a higher speed than the mark sheet reading apparatus that identifies the dropout color by analyzing the image data.

  Further, in order to identify the dropout color by image analysis, image data of the entire mark sheet 20 is usually required. For this reason, in the mark sheet reading apparatus that identifies the dropout color by image analysis, a waiting time occurs when the dropout color identification process is executed. On the other hand, the mark sheet reading apparatus 10 provides an identification code region at least one of the leading end and the trailing end of the mark sheet, and inserts the end portion on which the identification code is printed at the leading end, so that an image of the identification code region is obtained. Dropout color identification processing can be performed early after data is acquired.

  As described above, the mark sheet reading apparatus 10 can reduce both the processing time of the dropout color identification process itself and the waiting time generated when the dropout color identification process is executed. For this reason, the processing time of the whole mark sheet process can be shortened.

  Further, in the mark sheet reading device 10, every time three lines of image data from the color sensor 32 are output, the color data corresponding to the dropout color is removed from the output image data as needed. For this reason, since the waiting time that occurs when the dropout process is executed is reduced, the processing time of the entire mark sheet process can be shortened.

  Further, since the mark sheet reading apparatus 10 identifies the dropout color from the identification code, it is possible to reliably identify even a slight difference in the dropout color that is difficult to identify by image analysis.

Therefore, according to the mark sheet reading apparatus 10 according to the present embodiment, mark sheets printed with various dropout colors can be processed at high speed.
In FIG. 1, the color sensor 32 including three line sensors is illustrated, but the configuration of the color sensor included in the imaging device 30 is not limited to the configuration illustrated in FIG. 1. The imaging device 30 may include a color sensor including at least three line sensors.

  In FIG. 1, the light source 31 that emits illumination light composed of light of a plurality of wavelengths is illustrated to obtain RGB image data. However, the configuration of the light source included in the imaging device 30 is illustrated in FIG. 1. The configuration is not limited. The imaging device 30 may include, for example, a plurality of light sources that emit light having different wavelengths.

  2 illustrates the mark sheet 20 in which the identification code areas are provided at the front and rear ends of the mark sheet 20, but the configuration of the mark sheet used in the mark sheet reading apparatus 10 is limited to the configuration illustrated in FIG. I can't. The mark sheet used in the mark sheet reading apparatus 10 may include an identification code area at least one of the front end and the rear end of the mark sheet.

FIG. 6 is a functional block diagram of the mark sheet reading apparatus according to the present embodiment. The functional configuration of the mark sheet reading apparatus 50 according to the present embodiment will be outlined with reference to FIG.
Note that the mark sheet reading device 50 illustrated in FIG. 6 includes an imaging device 60 and an image processing device 70. The imaging device 60 is not illustrated, but is similar to the imaging device 30 illustrated in FIG. Although not shown, the image processing apparatus 70 includes an image memory as well as the image processing apparatus 40 illustrated in FIG. Further, the mark sheet used in the mark sheet reading apparatus 50 is the same as that of the mark sheet reading apparatus 10 according to the first embodiment, for example, the mark sheet 20 illustrated in FIG.

  The imaging device 60 emits illumination light composed of light of a plurality of wavelengths to illuminate the mark sheet 20, and image data for acquiring RGB multivalued image data from the reflected light of the mark sheet 20 by the light of the illumination unit 51 An acquisition unit 52. The illumination unit 51 corresponds to a light source, and the image data acquisition unit 52 corresponds to a color sensor.

  The image processing apparatus 70 includes a storage unit 53 that stores image data, a dropout color identification unit 54 that identifies a dropout color of the mark sheet 20, and RGB multivalued image data from which color data corresponding to the dropout color has been removed. A dropout processing unit 55 that generates RGB data, a single-coloring unit 56 that converts RGB multilevel image data into single-color multilevel image data, and binarizing the single-color multilevel image data to generate binary image data 2 A binarization unit 57; a mark detection unit 58 that detects the presence or absence of a mark written on the mark sheet 20 from the binary image data; and a DOC table 59 that defines the correspondence between the identification code and the dropout color. Yes. The storage unit 53 corresponds to an image memory. The DOC table 59 is the same as the DOC table 19 illustrated in FIG.

  FIG. 7 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. The processing method of the mark sheet 20 by the mark sheet reading device 50 will be specifically described with reference to FIGS. Hereinafter, a case where the mark sheet 20 is inserted into the imaging device 60 along the arrow illustrated in FIG. 2 will be described as an example.

  In step S201, when the mark sheet 20 is inserted into the imaging device 60 and processing by the mark sheet reading device 50 is started, the illumination unit 51 emits illumination light to illuminate the inserted mark sheet 20, and the light of the illumination unit 11 is emitted. The image data acquisition unit 52 acquires the RGB multi-value image data of the mark sheet 20 from the reflected light of the mark sheet 20 and outputs it to the image processing device 70.

In step S202, the storage unit 53 stores the RGB multivalued image data output from the image data acquisition unit 52.
In step S203, the dropout color identification unit 54 obtains the dropout color of the mark sheet 20 printed in the identification code area 21a from the RGB multilevel image data acquired by the image data acquisition unit 52 and stored in the storage unit 53. An identification code for identification is detected. And the dropout color of the mark sheet 20 is identified by acquiring the identification code number corresponding to the detected identification code from the DOC table 59 (illustrated in FIG. 5).

  In step S <b> 204, the dropout processing unit 55 corresponds to the dropout color identified by the dropout color identification unit 54 from the RGB multivalued image data acquired by the image data acquisition unit 52 and stored in the storage unit 53. Remove color data. As a result, the dropout processing unit 55 generates the RGB multivalued image data that has been dropped out from the data of the portion of the mark sheet 20 printed in the dropout color.

  In step S <b> 205, the monochromatic unit 56 converts the RGB multi-valued image data that has been dropped out generated by the drop-out processing unit 55 into single-color multi-valued image data that has been dropped out, and outputs the data to the storage unit 53.

In step S <b> 206, the storage unit 53 stores the single color multi-value image data output from the single color unit 56.
In step S207, the binarization unit 57 binarizes the single-color multivalued image data that has been dropped out and stored in the storage unit 53, and generates binary image data that has been dropped out.

  Finally, in step S208, the mark detection unit 58 detects the presence / absence of a mark written on the mark sheet 20 from the binary image data that has been dropped out and generated by the binarization unit 57.

  The specific methods of the dropout color identification process (step S203), dropout process (step S204), monochromatic process (step S205), and binarization process (step S207) executed by the mark sheet reading apparatus 50 are as follows. The method is the same as that performed by the mark sheet reading apparatus 10 according to the first embodiment.

  Further, the processes in step S201 and step S202 are started as soon as the output from the preceding step is received. That is, it is executed as a real-time process substantially. On the other hand, the processing from step S203 to step S208 is started after the image data of the entire mark entry area 22 is generated. That is, it is executed as non-real time processing.

  The mark sheet reading apparatus 50 according to the present embodiment is that the dropout color identification process, the dropout process, and the monochromatic process are executed by the image processing apparatus (image processing apparatus 70). The same function as that of the mark sheet reading device 10 is provided.

  Specifically, the mark sheet reading device 50 identifies the dropout color using the DOC table 59 from the identification code printed in the identification code area of the mark sheet 20. Therefore, the mark sheet reading device 50 can identify the dropout color at a higher speed than the mark sheet reading device that identifies the dropout color by analyzing the image data.

  Therefore, according to the mark sheet reading apparatus 50 according to the present embodiment, similarly to the mark sheet reading apparatus 10 according to the first embodiment, mark sheets printed in various dropout colors can be processed at high speed.

  FIG. 8 is a schematic configuration diagram of the mark sheet reading apparatus according to the present embodiment. The mark sheet reading apparatus according to the present embodiment will be outlined with reference to FIG. The mark sheet used in the mark sheet reading device 80 according to the present embodiment is the same as that of the mark sheet reading device 10 according to the first embodiment, for example, the mark sheet 20 illustrated in FIG.

  As illustrated in FIG. 8, the mark sheet reading device 80 includes an imaging device 90 that images the mark sheet 20 to generate image data of the mark sheet 20, and an image processing device 100 that detects the presence or absence of a mark from the image data. Contains.

  The imaging device 90 includes a light source 91 that emits light applied to the mark sheet 20 and a line sensor 92 that generates image data of the mark sheet 20. The light source 91 further includes a plurality of light sources (light source 91a, light source 91b, and light source 91c) that each emit light having different wavelengths. The image processing apparatus 100 includes an image memory 101 that stores image data of the mark sheet 20 generated by the imaging apparatus 90.

FIG. 9 is a functional block diagram of the mark sheet reading apparatus illustrated in FIG. The functional configuration of the mark sheet reading device 80 will be outlined with reference mainly to FIG.
The imaging device 90 emits illumination light to illuminate the mark sheet 20, an image data acquisition unit 82 that acquires multivalued image data from reflected light of the mark sheet 20 by light from the illumination unit 81, and the mark sheet 20 A dropout color identifying unit 83 that identifies the dropout color and a switching unit 84 that controls the operation of the illumination unit 81 are included. The illumination unit 81 corresponds to the plurality of light sources 91 (light source 91a, light source 91b, and light source 91c) illustrated in FIG. 8, and the image data acquisition unit 82 corresponds to the line sensor 92 illustrated in FIG.

  The image processing apparatus 100 includes a storage unit 85 that stores multi-value image data, a binarization unit 86 that binarizes the multi-value image data to generate binary image data, and a mark sheet 20 from the binary image data. And a mark detector 87 for detecting the presence or absence of the mark entered in The storage unit 85 corresponds to the image memory 101 illustrated in FIG.

  FIG. 10 is a flowchart illustrating a mark sheet processing method performed by the mark sheet reading apparatus illustrated in FIG. The processing method of the mark sheet 20 by the mark sheet reading device 80 will be specifically described mainly with reference to FIGS. Hereinafter, a case where the mark sheet 20 is inserted into the imaging device 90 along the arrow illustrated in FIG. 2 will be described as an example.

  In step S301, when the mark sheet 20 is inserted into the imaging device 90 and processing by the mark sheet reading device 80 is started, the illumination unit 81 emits illumination light to illuminate the inserted mark sheet 20, and the light of the illumination unit 81 The image data acquisition unit 82 acquires the multivalued image data of the mark sheet 20 from the reflected light of the mark sheet 20.

  In step S302, the dropout color identification unit 83 detects an identification code for identifying the dropout color of the mark sheet 20 printed in the identification code area 21a from the multivalued image data acquired by the image data acquisition unit 82. To do. Then, the dropout color of the inserted mark sheet 20 is identified from the detected identification code.

  More specifically, the mark sheet reading device 80 has a table (hereinafter referred to as a DOC table) in which the correspondence relationship between the identification code and the dropout color is defined as illustrated in FIG. The dropout color identification unit 83 detects an identification code that matches the pattern described in the column of the identification code symbol of the DOC table 88 from the identification code area 21a. Thereafter, the dropout color identification unit 83 identifies the dropout color of the mark sheet 20 by acquiring the identification code number corresponding to the detected identification code from the DOC table 88.

  In step S <b> 303, the switching unit 84 switches the wavelength of light emitted from the light source 91 and irradiated on the mark sheet 20 in accordance with the dropout color identified by the dropout color identifying unit 83.

  More specifically, the switching unit 84 drives a light source that emits light having a wavelength that is absorbed more at a portion of the mark sheet 20 printed in the dropout color among the light sources 91a, 91b, and 91c. The mark sheet 20 is illuminated by the light source.

  In step S <b> 304, the image data acquisition unit 82 acquires the multivalued image data of the mark sheet 20 illuminated by the switched light source (illumination unit 81) and outputs it to the image processing apparatus 100.

  Note that the multivalued image data of the mark sheet 20 acquired in step S304 is different from the multivalued image data acquired in step S301, and the dropout from which the data of the mark sheet 20 printed in the dropout color is removed. Multi-valued image data.

In step S <b> 305, the storage unit 85 stores the multi-valued image data that has been dropped out and is output from the image data acquisition unit 82.
In step S306, the binarization unit 86 binarizes the multi-valued image data that has been dropped out and stored in the storage unit 85, and generates binary image data that has been dropped out.

  More specifically, the binarization unit 86 analyzes the multi-value image data and determines a threshold value, and then binarizes the multi-value image data based on the threshold value. For this reason, the binarization unit 86 executes binarization processing after the multi-value image data of the entire mark entry area 22 of the mark sheet 20 is output to the storage unit 85 in order to calculate an appropriate threshold value.

  Finally, in step S307, the mark detection unit 87 detects the presence / absence of a mark written on the mark sheet 20 from the binary image data that has been dropped out and generated by the binarization unit 86.

  The processing from step S301 to step S305 is started as soon as the output from the preceding step is received. That is, it is executed as a real-time process substantially. On the other hand, the processes in steps S306 and S307 are started after the image data of the entire mark entry area 22 is generated. That is, it is executed as non-real time processing.

  The mark sheet reading device 80 identifies the dropout color from the identification code printed in the identification code area of the mark sheet 20 using a correspondence table such as a DOC table illustrated in FIG. For this reason, the mark sheet reading device 80 can identify the dropout color at a higher speed than the mark sheet reading device that identifies the dropout color by analyzing the image data.

  Further, in order to identify the dropout color by image analysis, image data of the entire mark sheet 20 is usually required. For this reason, in the mark sheet reading apparatus that identifies the dropout color by image analysis, a waiting time occurs when the dropout color identification process is executed. On the other hand, the mark sheet reading apparatus 80 can execute the dropout color identification process at an early stage after obtaining the image data of the identification code area by providing the identification code area at least one of the leading end and the trailing end of the mark sheet. it can.

  As described above, the mark sheet reading device 80 can reduce both the processing time of the dropout color identification process itself and the waiting time that occurs when the dropout color identification process is executed. For this reason, the processing time of the whole mark sheet process can be shortened.

  Further, in the mark sheet reading device 80, the wavelength of light emitted from the light source 91 and irradiated on the mark sheet 20 is switched according to the dropout color identified by the dropout color identification unit 83. For this reason, the image data of the mark entry area 22 acquired by the image data acquisition unit 82 has already been dropped out from which data of the portion of the mark sheet 20 printed in the dropout color has been removed. Image data. For this reason, it is not necessary to separately execute the dropout process, and the processing time of the entire mark sheet process can be shortened.

Therefore, according to the mark sheet reading apparatus 80 according to the present embodiment, it is possible to process mark sheets printed in various dropout colors at high speed.
In FIG. 8, in order to switch the wavelength of the light emitted from the light source 91 and applied to the mark sheet 20 in accordance with the dropout color, an imaging device 90 including a plurality of light sources each emitting light having different wavelengths is shown. Although illustrated, the configuration of the imaging device 90 is not limited to the configuration illustrated in FIG. The imaging device 90 includes, for example, one light source that emits illumination light composed of light of a plurality of wavelengths and a plurality of optical filters that have different transmission wavelength bands, and switches the wavelength of light irradiated to the mark sheet 20 by the optical filter. May be.

10, 50, 80 Mark sheet reading device 11, 51, 81 Illumination unit 12, 52, 82 Image data acquisition unit 13, 54, 83 Dropout color identification unit 14, 55 Dropout processing unit 15, 56 Monochromatic unit 16, 53 , 85 Storage unit 17, 57, 86 Binary unit 18, 58, 87 Mark detection unit 20 Mark sheet 21a, 21b Identification code region 22 Mark entry region 30, 60, 90 Imaging device 31, 91, 91a, 91b, 91c Light source 32 color sensor 32a, 32b, 32c, 92 line sensor 40, 70, 100 image processing device 41, 101 image memory 84 switching unit

Claims (4)

An image data acquisition unit for acquiring image data of the mark sheet;
An identification code for identifying a dropout color of the mark sheet printed in an identification code area provided on at least one of the front end and the rear end of the mark sheet from the image data acquired by the image data acquisition unit A dropout color identifying unit for detecting and identifying the dropout color from the detected identification code;
Mark detection for detecting the presence or absence of a mark written on the mark sheet from the image data after the drop-out from which the data of the mark sheet portion printed with the drop-out color identified by the drop-out color identification unit is removed A mark sheet reading device. The mark sheet reader according to claim 1, further comprising:
A drop for generating image data that has been dropped out by removing data of a color corresponding to the dropout color identified by the dropout color identification unit from the image data acquired by the image data acquisition unit A mark sheet reading apparatus including an out processing unit. The mark sheet reading device according to claim 2,
The image data acquisition unit includes a color sensor including at least three line sensors,
The dropout processing unit is configured to output the drop identified by the dropout color identification unit from the image data of at least three lines each time image data of at least three lines is output from the at least three line sensors. A mark sheet reading apparatus configured to remove color data corresponding to an out color. The mark sheet reader according to claim 1, further comprising:
A light source that emits light applied to the mark sheet;
A mark sheet reading apparatus comprising: a switching unit that switches a wavelength of light emitted from the light source and applied to the mark sheet according to the dropout color identified by the dropout color identification unit.