JP2013108798A - Image processing device and determination threshold setting method to be used in the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing device that allows easy setting of a determination threshold as a reference for determining quality of an object to be inspected while visually confirming a histogram, and to provide a determination threshold setting method to be used for the image processing device.SOLUTION: The image processing device calculates a matching degree between an image of an object captured by an imaging part and a master image stored in advance as a reference for comparison with the object, displays a histogram indicating a frequency distribution of the matching degrees calculated for a plurality of objects, displays the matching degree calculated for the object captured by the imaging part in association with the displayed histogram, and sets a threshold to be used for determining the quality of the object while displaying the histogram and the matching degree on the sam screen.

Description

  The present invention relates to an image processing apparatus that can easily set a determination threshold value that is a reference for determining pass / fail of an inspection object, and a determination threshold setting method used in the image processing apparatus.

  In the display device used in the image processing apparatus, various setting data can be set via the touch panel. Then, on the screen showing the result of the pass / fail determination of the inspection object, for example, a histogram showing the result of the pass / fail determination tried in the test mode is superimposed and the threshold determination for determining the pass / fail judgment threshold while visually checking the histogram is performed. The method is often used (see Patent Document 1).

  Further, a threshold setting method for setting a pass / fail judgment threshold by switching the display from a screen displaying a histogram to a screen for setting a pass / fail judgment threshold is also well known. That is, conventionally, the pass / fail judgment threshold is determined while visually checking the histogram, the display screen is switched, and the pass / fail judgment threshold is set.

JP 2008-297119 A

  However, with the conventional threshold setting method, an appropriate pass / fail judgment threshold can be estimated from the histogram, but it has not been possible to determine whether the estimated threshold is optimal. That is, even if a more suitable threshold value can be set in practice, there is a problem that there is no means for confirming it.

  For example, even if the entire inspection object cannot be imaged and only a part of the object can be imaged, it can be inferred that there are many results that are determined to be bad. It is not possible to determine pass / fail by appropriately adjusting the threshold value. In order to set an appropriate pass / fail judgment threshold according to the situation, it is desirable that the judgment result display screen, the pass / fail judgment threshold adjustment screen, and the histogram display screen be displayed in a superimposed manner.

  The present invention has been made in view of such circumstances, and an image processing apparatus capable of easily setting a determination threshold, which is a reference for determining the quality of an inspection object, while visually confirming a histogram, and the image processing apparatus It is an object of the present invention to provide a determination threshold setting method used in an image processing apparatus.

  In order to achieve the above object, an image processing apparatus according to a first invention includes an imaging unit that images an inspection object, and an image processing unit that performs image processing on image data captured by the imaging unit, In the image processing apparatus that determines the quality of the inspection object based on the processing result of the image processing unit, the image of the inspection object imaged by the imaging unit is compared with the inspection object stored in advance A degree of coincidence calculating unit that calculates a degree of coincidence with the master image to be obtained, a histogram display unit that displays a histogram indicating the frequency distribution of the degree of coincidence calculated for a plurality of inspection objects, and an inspection target imaged by the imaging unit The degree of coincidence calculated for the object is displayed in association with the histogram displayed by the histogram display unit, the histogram by the histogram display unit, In a state where the degree of coincidence is displayed on the same screen by 致度 display unit, characterized in that it comprises a threshold setting unit that sets a threshold used for quality determination of the inspection object.

  In the image processing apparatus according to the second invention, in the first invention, the threshold value setting unit is configured to be able to set a threshold value in association with the histogram displayed by the histogram display unit. Features.

  The image processing apparatus according to a third aspect of the present invention is the image processing apparatus according to the first or second aspect, wherein the histogram display unit superimposes and displays an image of the inspection object imaged by the imaging unit on the histogram. And

  The image processing apparatus according to a fourth aspect of the present invention is the image processing apparatus according to any one of the first to third aspects, wherein the threshold value setting unit includes a slider displayed in association with the histogram displayed by the histogram display unit. The threshold value can be set by operation.

  The image processing apparatus according to a fifth aspect of the present invention is the image processing apparatus according to the fourth aspect, wherein the threshold value setting unit displays the set threshold value superimposed on the histogram, and displays on the histogram in conjunction with the operation of the slider. It is characterized by changing.

  The image processing apparatus according to a sixth aspect of the present invention is the image processing apparatus according to the fifth aspect, wherein the threshold value setting unit displays the degree of coincidence calculated for the inspection object currently inspected within the movable range of the slider. And

  An image processing apparatus according to a seventh invention is characterized in that, in any one of the first to sixth inventions, the histogram display unit displays a background of the histogram in a translucent or transparent manner.

  An image processing apparatus according to an eighth invention is characterized in that, in any one of the first to seventh inventions, the histogram display section is configured not to display the histogram. And

  The image processing apparatus according to a ninth aspect is the image processing apparatus according to any one of the first to eighth aspects, wherein the histogram display unit calculates the degree of coincidence calculated based on the image data captured at the time of actual inspection of the inspection object. Is stored, and a histogram showing the stored frequency distribution of the degree of coincidence is displayed.

  Next, in order to achieve the above object, a determination threshold value setting method according to a tenth invention includes an imaging unit that images an inspection object, and an image processing unit that performs image processing on image data captured by the imaging unit In the determination threshold value setting method that can be executed by an image processing apparatus that determines the quality of an inspection object based on the processing result of the image processing unit, the image of the inspection object imaged by the imaging unit And a step of calculating a degree of coincidence with a master image serving as a reference to be compared with an inspection object stored in advance, and a step of displaying a histogram indicating the frequency distribution of the degree of coincidence calculated for a plurality of inspection objects. The step of displaying the degree of coincidence calculated for the inspection object imaged by the imaging unit in association with the displayed histogram, and the histogram and the information on the degree of coincidence are on the same screen. In the state shown, characterized in that it comprises a step of setting a threshold used for quality determination of the inspection object.

  The determination threshold value setting method according to the eleventh invention is characterized in that, in the tenth invention, a threshold value is set in association with the displayed histogram.

  The determination threshold value setting method according to the twelfth invention is characterized in that, in the tenth or eleventh invention, the image of the inspection object imaged by the imaging unit is displayed superimposed on the histogram.

  A determination threshold value setting method according to a thirteenth aspect of the invention is the method according to any one of the tenth to twelfth aspects of the invention, wherein the threshold value is set by operating a slider displayed in association with the displayed histogram. Features.

  The determination threshold value setting method according to the fourteenth aspect of the present invention is the method according to the thirteenth aspect, wherein the set threshold value is displayed superimposed on the histogram, and the display on the histogram is changed in conjunction with the operation of the slider. Features.

  The determination threshold value setting method according to the fifteenth aspect of the invention is characterized in that, in the fourteenth aspect, the degree of coincidence calculated for the inspection object currently inspected is displayed within the movable range of the slider.

  The determination threshold value setting method according to the sixteenth aspect of the invention is characterized in that, in any one of the tenth to fifteenth aspects, the background of the histogram is displayed in a translucent or transparent manner.

  A determination threshold value setting method according to a seventeenth aspect of the present invention is characterized in that, in any one of the tenth to sixteenth aspects, the histogram is not displayed.

  A determination threshold value setting method according to an eighteenth aspect of the present invention is the method according to any one of the tenth to seventeenth aspects, wherein the degree of coincidence calculated based on the image data captured during actual inspection of the inspection object is stored. A histogram showing the frequency distribution of the stored coincidence is displayed.

  In the first invention and the tenth invention, the degree of coincidence between the image of the inspection object imaged by the imaging unit and the master image serving as a reference to be compared with the inspection object stored in advance is calculated, and a plurality of inspections are calculated. A histogram showing the frequency distribution of the degree of coincidence calculated for the object is displayed. The degree of coincidence calculated for the inspection object imaged by the imaging unit is displayed in association with the displayed histogram, and the histogram and the information related to the degree of coincidence are displayed on the same screen. A threshold used for pass / fail judgment is set. You can set the threshold for pass / fail judgment while visually checking the histogram, so it is not necessary to switch the screen display to set the threshold, and set the threshold while checking how the pass / fail judgment results change. It is possible to easily set an optimum threshold value.

  In the second invention and the eleventh invention, the threshold value is set in association with the displayed histogram, so it can be set while always confirming visually which part of the frequency distribution the set threshold value corresponds to. There is no need to provide a plurality of devices.

  In the 3rd invention and the 12th invention, since the image of the inspection object imaged by the imaging unit is displayed superimposed on the histogram, the pass / fail judgment threshold value is set while constantly checking how the pass / fail judgment result changes. It is not necessary to provide a plurality of display devices.

  In the fourth invention and the thirteenth invention, the threshold value can be easily adjusted because the threshold value is set by operating the slider displayed in association with the displayed histogram.

  In the fifth invention and the fourteenth invention, the set threshold value is displayed superimposed on the histogram, and the display on the histogram is changed in conjunction with the operation of the slider. Therefore, the threshold value is set while visually checking the histogram. Therefore, it is possible to set a more appropriate threshold value.

  In the sixth and fifteenth inventions, the degree of coincidence calculated for the inspection object currently inspected is displayed within the movable range of the slider, so that the threshold can be set while comparing with the calculated degree of coincidence.

  In the seventh invention and the sixteenth invention, the background of the histogram is displayed semi-transparently or transparently so that the image of the inspection object can be displayed on the background of the histogram, and it is always possible to see how the result of pass / fail judgment changes. It is possible to set a pass / fail judgment threshold while checking.

  In the eighth invention and the seventeenth invention, since the histogram can be prevented from being displayed, it is possible to set an appropriate threshold without being influenced by the distribution of coincidence.

  In the ninth and eighteenth inventions, the degree of coincidence calculated based on the image data captured at the time of actual inspection of the inspection object is stored, and a histogram showing the frequency distribution of the stored degree of coincidence is displayed. The threshold value can be set in consideration of the latest external environment such as lighting and the conveyance speed of the inspection object.

  In the present invention, it is possible to set the pass / fail judgment threshold while visually checking the histogram, so there is no need to switch the screen display for setting the threshold, and the threshold is checked while the pass / fail judgment result changes. Thus, it is possible to easily set an optimum threshold value.

It is a schematic diagram which shows the structure of the image processing sensor which concerns on embodiment of this invention. 1 is an outline view showing a configuration of an imaging device of an image processing sensor according to an embodiment of the present invention. It is a block diagram which shows the hardware constitutions of the imaging device of the image processing sensor which concerns on embodiment of this invention. It is a front view which shows the structure of the display apparatus of the image processing sensor which concerns on embodiment of this invention. It is an illustration figure of the mode switching screen of the display apparatus of the image processing sensor which concerns on embodiment of this invention. It is an illustration figure of the setting screen of the display apparatus of the image processing sensor which concerns on embodiment of this invention. It is a functional block diagram of the image processing sensor which concerns on embodiment of this invention. It is an illustration figure of the threshold value adjustment screen in the case of displaying the histogram of the image processing sensor which concerns on embodiment of this invention. It is an illustration figure of the threshold value adjustment screen in case the histogram is not displayed of the image processing sensor which concerns on embodiment of this invention. It is an illustration figure of the threshold value adjustment screen in the case of making the background of a histogram transparent of the image processing sensor which concerns on embodiment of this invention.

  Hereinafter, an image processing apparatus according to an embodiment of the present invention will be described with reference to the drawings. Note that elements having the same or similar configuration or function are denoted by the same or similar reference numerals throughout the drawings referred to in the description of this embodiment, and detailed description thereof is omitted. Hereinafter, an image processing sensor will be described as an example of the image processing apparatus.

  FIG. 1 is a schematic diagram showing a configuration of an image processing sensor according to an embodiment of the present invention. As shown in FIG. 1, the image processing sensor according to the present embodiment includes an imaging device 1 and a display device 2 connected by a connection cable 3 so as to be able to perform data communication with the imaging device 1. Yes. Of course, instead of the display device 2, an external computer having a display may be used. Note that the imaging device 1 and the display device 2 may be configured integrally.

  The imaging apparatus 1 includes an FPGA, a DSP, and the like that execute image processing therein, and includes a camera module (imaging unit) having an imaging element that images the inspection target, and illumination that irradiates the inspection target with light. Department. In order to make the imaging device 1 compact, for example, as shown in FIG. 1, a lens 12 is arranged near the center of the front of the imaging device 1, and a plurality of LEDs 11 are arranged as an illumination unit so as to surround the lens 12. It is. Note that external illumination (ring illumination or the like) may be provided separately from the imaging device 1.

  FIG. 2 is an outline view showing the configuration of the imaging device 1 of the image processing sensor according to the embodiment of the present invention. 2A is a front view showing the configuration of the imaging device 1 of the image processing sensor according to the embodiment of the present invention, and FIG. 2B is the imaging of the image processing sensor according to the embodiment of the present invention. FIG. 2C is a plan view showing the configuration of the apparatus 1, and FIG. 2C is a rear view showing the configuration of the imaging apparatus 1 of the image processing sensor according to the embodiment of the present invention.

  As shown in FIG. 2A, the imaging apparatus 1 has a lens 12 disposed in the vicinity of the center of the front surface, and a plurality of LEDs 11 are disposed so as to surround the lens 12. At the time of imaging, by turning on the plurality of LEDs 11, it is possible to irradiate the inspection object with light and to clearly image the inspection object.

  As shown in FIGS. 2B and 2C, the rear surface of the imaging device 1 is in data communication with the display device 2 and a power connector 102 that connects a power cable that receives power supplied from an external power source. A connection connector 103 to which the connection cable 3 can be connected is provided. A focus adjustment screw 101 that can manually adjust the focus is also provided on the back surface.

  FIG. 3 is a block diagram showing a hardware configuration of the imaging device 1 of the image processing sensor according to the embodiment of the present invention. In FIG. 3, the connector board 16 is supplied with power from an external power source via a power connector 102 (see FIGS. 2B and 2C) provided in the power interface 161. The power supply board 18 supplies the supplied power to each board. In the present embodiment, power is supplied to the camera module 14 via the main board 13. The motor driver 181 of the power supply board 18 supplies driving power to the motor 141 of the camera module 14 to realize autofocus.

  The communication board 17 displays an OK / NG signal (determination signal, data indicating OK / NG), image data, and the like indicating whether the inspection object is good or not based on whether or not a defect output from the main board 13 is detected. Send to. The display device 2 that has received the determination signal displays the determination result. In this embodiment, an OK / NG signal (determination signal) is output via the communication board 17, but an OK / NG signal (determination signal) is output via the connector board 16, for example. Anyway.

  The illumination board 15 is provided with a plurality of LEDs 11 that irradiate light to an imaging region for imaging the inspection object, and a reflector (not shown) is provided in front of the LEDs 11. The lens 12 can be replaced as a lens unit for short distance or long distance.

  The camera module (imaging unit) 14 can control the autofocus operation when the motor 141 is driven. The inspection object is imaged according to the imaging instruction signal from the main board 13. In this embodiment, a CMOS substrate 142 is provided as an image sensor, and the captured color image is converted into an HDR image based on conversion characteristics that expands the dynamic range in the CMOS substrate 142 and output to the FPGA 131 of the main substrate 13. Is done.

  The main board 13 controls the operation of each connected board. For example, a control signal for controlling turning on / off of the plurality of LEDs 11 is transmitted to the LED driver 151 with respect to the illumination board 15. The LED driver 151 adjusts, for example, lighting / extinguishing of the LED 11, the amount of light, and the like according to a control signal from the FPGA 131. Further, a control signal for controlling the autofocus operation is transmitted to the motor 141 of the camera module 14 via the motor driver 181 of the power supply substrate 18, and an imaging instruction signal and the like are transmitted to the CMOS substrate 142. .

  The FPGA 131 of the main board 13 performs illumination control and imaging control, and executes image processing on the acquired image data (image processing unit). In addition, the DSP 132 of the main board 13 performs edge detection processing, pattern search processing, and the like on the image data. As a result of the pattern search process, an OK / NG signal (determination signal) indicating whether the inspection object is good or not is output to the communication board 17 depending on whether a defect is detected. The arithmetic processing result and the like are stored in the memory 133. In the present embodiment, the FPGA 131 executes illumination control, imaging control, and the like, but the DSP 132 may execute it. Further, a circuit in which the FPGA 131 and the DSP 132 are integrated, that is, a main control circuit (main control unit) may be provided. In short, a control signal for controlling turning on / off of the plurality of LEDs 11 is transmitted to the LED driver 151, a control signal for controlling the autofocus operation is transmitted to the motor 141 of the camera module 14, and an imaging instruction signal or the like is transmitted to the CMOS substrate. 142 may be provided, or a main control unit having the functions of both the FPGA 131 and the DSP 132 may be provided.

  FIG. 4 is a front view showing the configuration of the display device 2 of the image processing sensor according to the embodiment of the present invention. As shown in FIG. 4, a touch panel 21 is provided in the central portion of the front surface of the display device 2, displays a color image of the imaged inspection object on the screen, and accepts a selection input by the user.

  The display device 2 includes a power connector 24 that connects a power cable supplied with power from an external power source, and a connection connector 25 that can connect the connection cable 3 that performs data communication with the imaging device 1. Yes. Further, a USB port 22 that can be connected to a USB memory or the like is provided on the front surface.

  The user controls the operation of the image processing sensor by selecting a button displayed on the screen of the touch panel 21 of the display device 2. It is also possible to switch between an “inspection mode” for inspecting an inspection object and a “setting mode” for setting conditions of the image processing sensor. In other words, the image processing sensor according to the present embodiment sets an inspection mode (Run mode) for determining the quality of an inspection object and various parameters (imaging parameters, illumination parameters, image processing parameters, etc.) used for the inspection. A mode switching unit for switching between setting modes to be performed (non-Run mode) is provided. FIG. 5 is an exemplary view of a mode switching screen of the display device 2 of the image processing sensor according to the embodiment of the present invention.

  FIG. 5A is a view showing an example of the screen display of “inspection mode”. As shown in FIG. 5A, the inspection object image captured by the imaging apparatus 1 is displayed in the inspection object display area 51. The lower left “sensor setting” button 52 functions as a mode switching unit, and when the “sensor setting” button 52 is selected, the mode is switched to “setting mode”, and the screen transitions to the screen shown in FIG.

  FIG. 5B is an exemplary view of a screen display of “setting mode”. As shown in FIG. 5B, in the program selection area 53, the type of inspection object or the inspection environment is selected. Here, the “program” means a series of data groups (combination of parameter values) set in accordance with the type of inspection object or the inspection environment, and varies depending on the type of inspection object or the inspection environment. A group of data can be stored as a program. When the “threshold adjustment” button 57 is selected, a threshold adjustment screen is displayed. The threshold adjustment screen will be described later.

  When a master image serving as a reference for comparison with the inspection object is stored, the master image is displayed in the master image display area 54. When the “setting navigation” button 55 is selected, the screen transitions to a setting screen for performing detailed settings. The “start operation” button 56 in the lower left functions as a mode switching unit. When the “start operation” button 56 is selected, the mode is switched to “inspection mode” and the screen transitions to the screen shown in FIG.

  FIG. 6 is an exemplary view of a setting screen of the display device 2 of the image processing sensor according to the embodiment of the present invention. Through the setting screen shown in FIG. 6, the user can set the imaging conditions (FIG. 6A), register the master image as a reference for pattern search (FIG. 6B), and set tools such as contour search for the master image. The settings are sequentially made in the order of (FIG. 6C to FIG. 6E) and output assignment (FIG. 6F). Details will be described below. When the “setting navigation” button 55 shown in FIG. 5B is selected, first, an imaging condition setting screen shown in FIG. 6A is displayed. On the imaging condition setting screen, when a master image is stored, the master image is displayed in the main display area 61, and a setting button group for setting imaging conditions is displayed at the bottom of the screen. For example, when the “trigger condition” button is selected, it is possible to set a trigger condition that specifies the timing at which the imaging apparatus 1 images the inspection object. Although a detailed setting screen is omitted, when each button is selected, it is displayed on the touch panel 21 shown in FIG. 4 according to each setting condition.

  Note that even if a master image is not stored or a master image is stored, an image that is currently captured (hereinafter, a live image) may be displayed in the main display area 61. Also in this case, as described later, when the “Live image registration” button 64 is selected, the currently captured image is registered as the original image of the master image.

  For more detailed setting, the “extended function” button 62 in FIG. 6A may be selected. When the “extended function” button 62 is selected, a button for performing detailed settings is separately displayed. Thus, on the imaging condition setting screen, brightness adjustment, focus adjustment, imaging range, illumination on / off, zoom on / off, and the like can be set.

  When the “screen transition” button 63 displayed as “advance” in FIG. 6A is selected, a master image registration screen shown in FIG. 6B is displayed. Thereafter, various tools for inspection are set on the registered master image. A plurality of programs can be stored for one master image. That is, different tools can be set for the same master image and stored as different programs.

  As the master image, an image currently captured may be registered, or a master image may be selected and registered from previously captured images. When registering an image currently captured, the user may select a “Live image registration” button 64. An image captured at the time when the “Live image registration” button 64 is selected is registered as a master image.

  When the “screen transition” button 65 displayed as “advance” in FIG. 6B is selected, a tool setting screen for each master image shown in FIG. 6C is displayed. Thereafter, various tools for inspection are set on the master image.

  On the tool setting screen, a tool for executing inspection is additionally set to the displayed master image. When the “add” button 66 shown in FIG. 6C is selected, a tool selection screen shown in FIG. 6D is displayed. Set additional tools selected on the tool selection screen. For example, when the “contour search” button 67 is selected, a contour search setting screen shown in FIG. 6E is displayed. By setting which contour of the master image is to be checked against the image of the imaged inspection object on the contour search setting screen, the quality of the inspection object can be determined based on whether or not a defect has been detected. . Hereinafter, settings such as color area and position correction can be made.

  When the “screen transition” button 68 displayed as “advance” in FIG. 6C is selected, an output assignment screen shown in FIG. 6F is displayed. On the output assignment screen, it is possible to set what the output line displayed on the screen as a result of the inspection means. When the “complete” button 69 is selected, the screen returns to the “setting mode” screen shown in FIG. In this manner, the user can easily and quickly select the “screen transition” buttons 63, 65, and 68 displayed as “forward” on the touch panel 21 of the display device 2 illustrated in FIG. Various parameters used for inspection can be set. Further, even a user who is not familiar with the image processing sensor is guided to the next operation on the display device 2, so that various parameters can be easily set.

  When the “threshold adjustment” button 57 in FIG. 5B is selected, a threshold adjustment screen for setting a threshold value for pass / fail determination of the inspection object is displayed, and threshold setting processing is executed. FIG. 7 is a functional block diagram of the image processing sensor according to the embodiment of the present invention.

  In FIG. 7, the degree-of-match calculation unit 701 calculates the degree of coincidence between the image of the inspection object imaged by the imaging device 1 and a master image serving as a reference for comparison with the inspection object stored in advance. Specifically, for example, the position of the image of the imaged inspection object is corrected, the contour is extracted, and the degree of coincidence with the master image is calculated.

  Of course, when the position correction tool is not set, position correction is not performed, and when the contour extraction tool is not set, contour extraction is not performed. In short, a unique determination value for each tool is calculated from the image of the inspection object, and a degree of coincidence indicating how much the calculated determination value matches the determination value in the master image is calculated. For example, in the case of color area inspection, a predetermined color area is calculated from the image of the inspection object, and a degree of coincidence indicating how much the predetermined color area in the master image matches is calculated. (100% if the color areas are completely matched)

  The histogram display unit 702 displays a histogram indicating the frequency distribution of the degree of coincidence calculated for a plurality of inspection objects. The histogram to be displayed shows the degree of coincidence on the horizontal axis and the frequency on the vertical axis.

  In the conventional threshold value setting method, a histogram indicating the result of pass / fail judgment made in a test mode or the like is generated. In this case, the number of samplings is not so high as around 1000.

  However, in this embodiment, each time an inspection object is actually inspected, the degree of coincidence of the captured images may be calculated, and a histogram indicating the frequency distribution of the calculated degree of coincidence may be generated. In this case, there is no restriction on the number of samplings, and it is also possible to generate a histogram by extracting only the degree of coincidence calculated at the time of the most recent inspection, so the latest external environment such as lighting and the conveyance speed of the inspection object is taken into consideration It is possible to set a threshold value in

  FIG. 8 is an exemplary diagram of a threshold adjustment screen when displaying a histogram of the image processing sensor according to the embodiment of the present invention. In the example of FIG. 8, the threshold is displayed as “judgment value”.

  Whether or not to display the histogram is switched by selecting an “ON / OFF” button 81. When displaying the histogram, the threshold adjustment screen displays the histogram superimposed on the approximate center of the screen together with the image of the inspection object. In the numerical value display area 82, the measured value of the histogram and the threshold value for pass / fail judgment are displayed. In the example of FIG. 8, the latest value of the matching degree displayed in the histogram is “30” (%), the maximum value (MAX) is “100” (%), and the minimum value (MIN) is “2” (%). The average value (AVE) is “75” (%), and the currently set pass / fail threshold value (determination value) is “72” (%). In FIG. 8, the degree of coincidence is displayed as a percentage (%), but it may be displayed as a numerical value (ratio) greater than 0 and less than 1.

  Returning to FIG. 7, the coincidence degree display unit 703 displays the coincidence degree calculated for the inspection object currently being inspected, superimposed on the histogram. In FIG. 8, as shown in the coincidence degree display area 83, “Δ” is displayed on the histogram, and the bar length is displayed within the movable range of the slider 84. In accordance with the change in the degree of coincidence, the “Δ” mark moves, and the length of the bar inside the slider 84 changes. Therefore, it is possible to visually confirm the degree of coincidence of the inspection object currently inspected with respect to the frequency distribution of the coincidence degree of the plurality of inspection objects.

  In the present embodiment, the degree of coincidence of the inspection object is displayed using both the “△” mark and the bar length as described above. It is not limited. For example, it may be displayed only by “Δ” mark, may be displayed only by the length of the bar, or may be displayed by a coincidence line such as a threshold line 86 described later. Further, the degree of coincidence of the inspection object may be displayed by changing the color of a part of the degree of coincidence of the histogram without using these figures. In short, information (numerical value, figure, symbol, etc.) relating to the degree of coincidence calculated for the currently displayed inspection object may be displayed in association with the horizontal axis of the histogram.

  The threshold setting unit 704 operates the slider 84 displayed on the screen to set a pass / fail judgment threshold. Specifically, the threshold value to be set is changed by moving the knob portion 85 of the slider 84 to the left and right. As the knob portion 85 moves, the threshold line 86 displayed superimposed on the histogram moves to the left and right. In addition, the numerical value displayed in the threshold value display area 87 and the threshold value (determination value) for quality determination displayed in the numerical value display area 82 are also changed.

  Of course, it is also possible to set a pass / fail judgment threshold value by directly inputting a numerical value into the threshold value display area 87. In this case, the determination value displayed in the numerical value display area 82 is changed according to the input numerical value, the knob portion 85 of the slider 84 moves, and the threshold line 86 also moves accordingly. Further, the threshold line 86 may be moved to set a pass / fail judgment threshold. Also in this case, the numerical value displayed in the threshold value display area 87 and the determination value displayed in the numerical value display area 82 are changed according to the movement of the threshold value line 86, and the knob portion 85 of the slider 84 moves.

  In the present embodiment, as described above, all of the numerical values input to the threshold display area 87, the threshold line 86, and the knob portion 85 of the slider 84 are displayed in conjunction with each other, so that the usability of the user (the threshold value) (Ease of setting) is improved, but it is possible to set a threshold without displaying these in conjunction with each other. For example, the interlock display of the threshold line 86 and the knob portion 85 of the slider 84 may be omitted, and the threshold value may be set only by inputting a numerical value to the threshold display area 87. Further, it is possible to omit the numerical value input to the threshold display area 87 and the interlocking display of the knob portion 85 of the slider 84 and set the threshold only by moving the threshold line 86. Further, unlike the threshold line 86, the degree of coincidence indicated by the selected point may be set as the threshold by selecting (touching) an arbitrary point in the area where the histogram is displayed.

  In short, it suffices if the threshold value used for pass / fail judgment of the inspection object can be set in a state where the histogram and the information about the degree of coincidence calculated for the inspection object are displayed. However, as described above, by setting the threshold value in association with the degree of coincidence of the displayed histogram as in the present embodiment, it is possible to improve the ease of setting the threshold value as described above. Further, the threshold value can be easily set (ease of visual recognition) by displaying it superimposed on the histogram like the threshold line 86.

  When the histogram is not displayed, only the captured image of the inspection object is superimposed and displayed on the threshold adjustment screen. FIG. 9 is a view for showing an example of a threshold adjustment screen when the histogram is not displayed in the image processing sensor according to the embodiment of the present invention.

  As shown in FIG. 9, an image of the inspection object imaged at the center of the screen is displayed, and a slider 84 and a threshold display area 87 similar to those in FIG. 8 are displayed at the bottom of the screen. The quality determination result of the inspection object can be visually confirmed by displaying the result display area 91. In the example of FIG. 9, a rectangular frame is displayed in the result display area 91. For example, when the rectangular frame is displayed in green, “good” determination is displayed, and the rectangular frame is displayed in red. In each case, a 'no' decision is shown.

  Of course, it is not limited to distinguishing by display color, and in the case of “No” determination, a rectangular frame may be displayed blinking, or an “x” mark may be displayed in the rectangular frame. . There is no particular limitation as long as the user can visually confirm the quality determination result of the inspection object.

  In addition, when both are superimposed and displayed so that the pass / fail judgment result of the inspection object and the histogram can be confirmed without switching the display image, the background of the histogram is made translucent as shown in FIG. Thus, it is possible to make it easy to see the quality determination result of the inspection object. In order to make the quality determination result of the inspection object easier to see, the background of the histogram may be transparent.

  FIG. 10 is a view for showing an example of a threshold adjustment screen when the background of the histogram is transparent in the image processing sensor according to the embodiment of the present invention. In FIG. 10, the image of the imaged inspection object is marked with an asterisk (*) for easy understanding, and the entire asterisk is used as the result display area 91, but the basic screen configuration is the same as in FIG.

  Then, by selecting the “OK” button 88 in FIG. 8 to FIG. 10, the threshold value setting process is terminated.

  As described above, according to the present embodiment, it is not necessary to switch the screen display for setting the threshold value, and the pass / fail judgment threshold value can be set while visually confirming the histogram. Therefore, the threshold value can be set while confirming how the result of the pass / fail judgment changes, and the optimum threshold value can be easily set.

  The present invention is not limited to the above-described embodiments, and various changes and improvements can be made within the scope of the present invention. For example, the imaging device 1 and the display device 2 are not limited to the form directly connected by the connection cable 3, and needless to say, they may be connected via a network such as a LAN or WAN.

DESCRIPTION OF SYMBOLS 1 Imaging device 2 Display device 3 Connection cable 13 Main board 14 Camera module (imaging part)
21 Touch Panel 131 FPGA (Image Processing Unit)
701 Matching degree calculation part 702 Histogram display part 703 Matching degree display part 704 Threshold setting part

Claims (18)

An imaging unit for imaging an inspection object;
In an image processing apparatus comprising: an image processing unit that performs image processing on image data captured by the imaging unit, and determining whether or not an inspection object is good based on a processing result of the image processing unit;
A degree of coincidence calculation unit for calculating a degree of coincidence between an image of the inspection object imaged by the imaging unit and a master image serving as a reference for comparison with the inspection object stored in advance;
A histogram display for displaying a histogram indicating the frequency distribution of the degree of coincidence calculated for a plurality of inspection objects;
A coincidence degree display unit that displays the degree of coincidence calculated for the inspection object imaged by the imaging unit in association with the histogram displayed by the histogram display unit;
A threshold value setting unit that sets a threshold value used for quality determination of an inspection object in a state where the histogram by the histogram display unit and the matching level by the matching level display unit are displayed on the same screen. An image processing apparatus.   The image processing apparatus according to claim 1, wherein the threshold setting unit is configured to be able to set a threshold in association with the histogram displayed by the histogram display unit.   The image processing apparatus according to claim 1, wherein the histogram display unit displays an image of the inspection object imaged by the imaging unit so as to be superimposed on the histogram.   The threshold value setting unit is configured to be able to set the threshold value by operating a slider displayed in association with the histogram displayed by the histogram display unit. The image processing apparatus according to any one of claims 3 to 4.   The image processing apparatus according to claim 4, wherein the threshold value setting unit displays the set threshold value superimposed on the histogram, and changes the display on the histogram in conjunction with the operation of the slider. .   The image processing apparatus according to claim 5, wherein the threshold setting unit displays the degree of coincidence calculated for the inspection object currently inspected within the movable range of the slider.   The image processing apparatus according to claim 1, wherein the histogram display unit displays a background of the histogram in a translucent or transparent manner.   The image processing apparatus according to claim 1, wherein the histogram display unit is configured not to display the histogram. The histogram display unit stores the degree of coincidence calculated based on image data captured at the time of actual inspection of the inspection object,
The image processing apparatus according to claim 1, wherein a histogram showing a frequency distribution of stored coincidence is displayed. An imaging unit for imaging an inspection object;
An image processing unit that performs image processing on image data captured by the imaging unit, and can be executed by an image processing apparatus that determines the quality of an inspection object based on the processing result of the image processing unit In the determination threshold setting method,
Calculating the degree of coincidence between the image of the inspection object imaged by the imaging unit and a master image serving as a reference for comparison with the inspection object stored in advance;
Displaying a histogram showing the frequency distribution of the degree of coincidence calculated for a plurality of inspection objects;
Displaying the degree of coincidence calculated for the inspection object imaged by the imaging unit in association with the displayed histogram;
A threshold value setting method for setting a threshold value used for quality determination of an inspection object in a state where the histogram and the information on the degree of coincidence are displayed on the same screen.   The determination threshold value setting method according to claim 10, wherein a threshold value is set in association with the displayed histogram.   The determination threshold value setting method according to claim 10 or 11, wherein an image of the inspection object imaged by the imaging unit is displayed superimposed on the histogram.   The determination threshold value setting method according to any one of claims 10 to 12, wherein the threshold value is set by operating a slider displayed in association with the displayed histogram.   14. The determination threshold value setting method according to claim 13, wherein a threshold value to be set is displayed superimposed on the histogram, and the display on the histogram is changed in conjunction with an operation of the slider.   15. The determination threshold value setting method according to claim 14, wherein the degree of coincidence calculated for the inspection object currently inspected is displayed within the movable range of the slider.   The determination threshold value setting method according to any one of claims 10 to 15, wherein a background of the histogram is displayed in a translucent or transparent manner.   The determination threshold value setting method according to any one of claims 10 to 16, wherein the histogram is not displayed. Store the degree of coincidence calculated based on the image data captured during the actual inspection of the inspection object,
The determination threshold value setting method according to any one of claims 10 to 17, wherein a histogram showing a frequency distribution of stored matching degrees is displayed.