JPH11132740A - Image measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect edge of an object to be measured by a simple operation. SOLUTION: When an instruction for a section to be measured with respect to an image is given by a mouse 42b in a state where the image by picture image data 51B stored in a memory 41D is displayed on a display screen of a display 43, the contents of the instruction are input in a program 53B for inputting measuring conditions, and coordinates of an edge point closest to the point given by the instruction by a program 53D for detecting edge and coordinates of edge points of at least two points close to the edge point are detected. Edge elements are recognized based on the coordinates of the edge points of at least three points by a program 53F for recognizing shape to recognize the shape of an object to be measured. In this way, the shape recognition including edge detection of the object to be measured can be done by such a simple operation that sections to be measured are instructed using the mouse 42b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image measuring apparatus, and more particularly, to detecting a plurality of points on an outline of an object from image information of the object, and performing shape recognition and other measurement processing based on the detected points. The present invention relates to an image measurement device for performing.

[0002]

2. Description of the Related Art An image measuring apparatus used in the industrial and medical fields not only displays an image of an object obtained by imaging on a display screen of a display, but also displays an image of the object on the contour of the object based on image information of the object. Are extracted, and measurement processing is performed based on the extracted points. In particular, since the edge detection processing for detecting the contour, ie, the edge, of the target object from the image information is premised on performing various measurement processing such as length and area measurement from the image, it is necessary to perform the processing prior to these processings.

[0003] One of the measurement processing programs for edge detection is a measurement processing program called a caliper tool. With this caliper tool, a predetermined small range for edge detection is set on a part of the edge (contour) of the image of the object, and the coordinates of points on the edge in that range are automatically detected. It is supposed to.

[0004]

However, in the measurement using the above-mentioned caliper tool, the operator uses the caliper which is a mark (mark) of the edge position detection area displayed on the screen and indicating the target range, position and direction of edge detection. Is moved to a position to be measured in the image of the target object with the mouse, and the tilt (direction) of the caliper is designated each time with the mouse in accordance with the direction of the edge, so that the predetermined range to be subjected to edge detection is determined. Must be set on the edge of the image. For this reason, the operation of grabbing the caliper with a mouse, moving to a measurement location, and changing the direction of the caliper in accordance with the direction of the edge become indispensable, which has caused the operation to be cumbersome.

The present invention has been made under such circumstances, and an object of the present invention is to provide an image measuring apparatus capable of performing edge detection with a simpler operation.

[0006]

According to the first aspect of the present invention, the shape of the measurement object (10) is obtained by using image information (51B) obtained by capturing an image of the measurement object (10). A memory (41D) for storing the image information; an image display device (43) for displaying an image corresponding to the image information on a display screen; and displaying on the display screen Point input means (42b, 53B) for inputting an instruction of a point in the vicinity of the measurement point with respect to the obtained image
Based on the position information and gradation information of each pixel included in the image information (51B) in the memory (41D), and exists near the point designated by the point input means (42b, 53B). First edge detecting means (53D1) for detecting an edge coordinate which is a coordinate of a point on an edge satisfying a predetermined condition among a plurality of points on the edge of the image (10 ') of the object (10); Setting a plurality of lines in a direction connecting the designated point and the reference point within a predetermined range including a point on the edge where the edge coordinates are detected as a reference point,
For at least two lines other than the line including the reference point of the plurality of lines, coordinates of points on an edge are determined for each line based on position information and gradation information of each pixel included in image information in the memory. A second edge detecting means for detecting (53D2); an edge element to which the three points belong based on the coordinates of at least three points on the edges adjacent to each other detected by the first and second edge detecting means; And a shape recognizing means (53F) for recognizing at least a part of the shape of the measurement object by recognizing the type of the object.

According to this, in a state where an image corresponding to the image information stored in the memory is displayed on the display screen of the image display device, the image of the point in the vicinity of the measurement point is input to the image by the point input means. When an instruction is input, an object existing near the point designated by the point input means based on the position information and the gradation information of each pixel included in the image information in the memory by the first edge detection means. Edge coordinates are detected, which are coordinates of points on the edge that is closest to the plurality of points on the edge of the object image. Next, a plurality of lines are set by the second edge detecting means in a direction connecting the designated point and the reference point within a predetermined range including the point on the edge at which the edge coordinates are detected as the reference point, and the plurality of lines are set. For at least two lines other than the line including the reference point, the coordinates of the point on the edge are detected for each line based on the position information and the gradation information of each pixel included in the image information in the memory. Then, by the shape recognizing means, at least three points which are close to each other and detected by the first and second edge detecting means.
By recognizing the type of the edge element to which the three points belong based on the coordinates of the point on the edge of the point, at least a part of the shape of the measurement target is recognized. Therefore, the edge detection and the shape recognition of the measurement target can be performed only by a simple operation of inputting a point indicating a measurement location.

According to a second aspect of the present invention, in the image measuring device of the first aspect, measurement condition input means (42b, 42a, 53) for inputting an instruction of an arbitrary geometric shape.
B), and a measuring means (53H) for performing a measuring process for obtaining a geometric shape specified by the measuring condition input means, wherein the measuring means (53H) is provided with the shape recognizing means (5).
The method is characterized in that parameters of a geometric shape corresponding to the instruction are obtained from the shapes recognized by 3F).

According to this, when an instruction of an arbitrary geometric shape is inputted by the measurement condition input means, the measuring means obtains a parameter of the geometric shape corresponding to the instruction from the shapes recognized by the shape recognizing means. Therefore, a measurement result of the geometric shape can be obtained by a simple operation of inputting an instruction of an arbitrary geometric shape.

According to a third aspect of the present invention, the measurement object (1
An image measurement device for measuring the shape of the measurement object (10) using image information (51B) obtained by imaging the image of (0), and a memory (41D) for storing the image information
An image display device (43) for displaying an image corresponding to the image information on a display screen; and a point for inputting an instruction of a point near a measurement point with respect to the image displayed on the display screen. Input means (42b, 53B); and the memory (4
1D) based on the position information and the gradation information of each pixel included in the image information (51B) within the point input means (42).
b, 53B) is an edge coordinate which is a coordinate of a point on an edge which satisfies a predetermined condition among a plurality of points on an edge of the image (10 ′) of the object (10) existing near the point designated by (b). First edge detecting means (53D1) for detecting; a plurality of lines in a direction connecting the designated point and the reference point within a predetermined range including a point on the edge at which the edge coordinates are detected as a reference point; For at least two lines other than the line including the reference point of the plurality of lines, on the edge based on the position information and the gradation information of each pixel included in the image information in the memory for each line. A second edge detecting means (53D2) for detecting the coordinates of the point, wherein the second edge detecting means (53D2) comprises an edge coordinate of the reference point and coordinates on at least two edges near the reference point. Based on A straight line element and a normal line of the straight line element based on the straight line element and a gradation change of a pixel existing on a line in a direction connecting the designated point including the reference point and the reference point. It is characterized by further having a function of obtaining a vector.

According to this, while an image corresponding to the image information stored in the memory is displayed on the display screen of the image display device, the image of the point in the vicinity of the measurement point is input to the image by the point input means. When an instruction is input, an object existing near the point designated by the point input means based on the position information and the gradation information of each pixel included in the image information in the memory by the first edge detection means. Edge coordinates are detected, which are coordinates of points on the edge that is closest to the plurality of points on the edge of the object image. Next, a plurality of lines are set by the second edge detecting means in a direction connecting the designated point and the reference point within a predetermined range including the point on the edge at which the edge coordinates are detected as the reference point, and the plurality of lines are set. For at least two lines other than the line including the reference point, the coordinates of the point on the edge are detected for each line based on the position information and the gradation information of each pixel included in the image information in the memory. In this case, regardless of whether the edge including the reference point is a straight line or a curve, the second edge detecting means (53D2
) Recognizes a linear element (element by least squares approximation) based on the edge coordinates of the reference point and the coordinates on at least two edges near the reference point, and specifies the specified element including the linear element and the reference point. The normal vector of the linear element is reliably obtained based on the gradation change of the pixel existing on the line in the direction connecting the point and the reference point (the general direction of the normal vector of the linear element can be determined). be able to.

In each of the first to third aspects of the present invention, the first edge detecting means designates a designated point based on position information and gradation information of each pixel contained in the image information in the memory. Any method may be used as long as it detects edge coordinates that are coordinates of a point on an edge existing in the vicinity of the edge. For example, as in the invention according to claim 4, 1 edge detecting means (53D1)
Detecting points on a plurality of edges based on position information and gradation information of pixels existing on a plurality of radial lines in the search direction centered on the point indicated by the point input means, The coordinates of the point having the shortest distance from the designated point among these points may be detected as the edge coordinates. In such a case, points on a plurality of edges are detected based on position information and gradation information of pixels present on a plurality of radial lines in the search direction centered on the designated point, and among these points, Since the coordinates of the point having the shortest distance from the designated point are detected as edge coordinates, for example, the edge detection is performed in comparison with the case where the radius of a concentric circle centered on the designated point is gradually increased to measure the edge coordinates. , The number of pixels used is reduced, and rapid edge detection becomes possible. In this case, by increasing the search direction, it becomes possible to more accurately detect the coordinates of a point on the edge that is closest to the designated point.

Alternatively, as in the invention described in claim 5,
The first edge detecting means (53D1) has a predetermined rectangular area (R) centered on the point designated by the point input means.
A plurality of lines in the row direction and the column direction are set in the memory, and in each of the row direction and the column direction, a line including the designated point, and at least two lines other than the line, are stored in the memory for each line. The coordinates of the point on the edge are detected based on the position information and the gradation information of each pixel included in the image information, and the coordinates of the point having the shortest distance from the designated point among these points are determined. Edge coordinates may be used.

According to a sixth aspect of the present invention, the measuring object (1
An image measurement device for measuring the shape of the measurement object using image information (51B) obtained by imaging the image of (0), wherein the memory (41) stores the image information (51B).
D); an image display device (43) for displaying an image corresponding to the image information on a display screen; and a mark (S) indicating the target range, position and direction of edge detection displayed on the screen. Mark position moving means (53J, 42b) for moving the mark (S) to the position of the mark (S); with the movement of the mark (S), the coordinates of a point on an edge included in the target range of edge detection by the mark are obtained in real time. Real-time detection means (53H).

According to this, as the mark moves, the coordinates of a point on the edge included in the target range of the edge detection by the mark are obtained in real time by the real-time detecting means. Therefore, by displaying the coordinates of the point on the edge obtained in real time on the screen, the position of the edge coordinate in the mark can be immediately recognized. Here, the edge coordinates may be any of orthogonal coordinates (X, Y) and polar coordinates (r, θ) with an arbitrary point as the origin.

In this case, as in the invention according to claim 7, the real-time detection means (53H) detects a point on an edge included in a range of the edge detection target area during the movement of the mark. Based on the coordinates, the distance between a plurality of points on the contour of the measurement object, the length of a perpendicular to an arbitrarily selected straight line or the distance to an arbitrarily selected point, or the arbitrarily selected point as an end point It is desirable to further have a function of obtaining an angle formed by an arbitrarily selected straight line including each of the straight lines and a straight line passing through the point on the edge in real time. In this case, the distance between edge points that are points on the outline of the object within the target range of edge detection, the length of a perpendicular to an arbitrarily selected straight line, or the distance to an arbitrarily selected point, or An angle formed by an arbitrarily selected straight line including the arbitrarily selected point as an end point and a straight line passing through a point on the edge is calculated in real time. Therefore, various measurements based on the image of the target object can be automatically performed only by moving the mark. In particular, the measurement of the distance between the arbitrarily selected point or the angle formed by the arbitrarily selected straight line including the arbitrarily selected point as an end point and the straight line passing through the point on the edge, for example, the arbitrary It is also possible to use polar coordinates with the selected point as the origin.

Alternatively, as in the invention described in claim 8,
The real-time detecting means (53H) obtains, in real time, a normal vector of a point on the edge for which the coordinates have been obtained, sets the angle of the moving mark in the same direction as the normal vector, and displays the mark on the screen in real time. May be further provided.

In this case, the mark is displayed in real time on the screen in the same direction as the normal vector, so that it is easy to know in which direction the measurement is being performed. Further, points on the edge can be detected with high accuracy.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

FIG. 1 schematically shows the entire configuration of an image measuring apparatus according to one embodiment. The image measuring apparatus shown in FIG. 1 includes a measuring object (hereinafter, referred to as an “object”) 10
Is a device that measures the shape and the like of the target object 10 using image data that is image information obtained by capturing an image of the imaging device 20, the imaging unit 20, the light source unit 60, the interface unit 30, the host computer 40, and the like. It has.

The image pickup unit 20 is a component for picking up an image of an object 10 (for example, a mechanical component, a semiconductor chip, a liquid crystal display panel, or a biological or biological sample). The imaging unit 20 includes an XY stage 22 on which the object 10 is placed and which can move two-dimensionally on a base 21;
An optical system unit 24 is disposed above the XY stage 22 and is fixed to a support 23 implanted on the base 21.

This will be described in more detail.
Reference numeral 2 denotes a Y stage 22Y that moves on the base 21 in the Y direction (a direction perpendicular to the plane of FIG. 1),
And an X stage 22X that is movable in the X direction orthogonal to the Y direction on the 2Y (in the horizontal direction in FIG. 1). The object 10 is placed on the X stage 22X. The Y stage 22Y and the X stage 22X are driven by a drive system including a linear actuator (not shown) controlled by a control unit 31 in the interface unit 30 described later. Further, the positions of the Y stage 22Y and the X stage 22X are measured by a position detecting device such as a laser interferometer or an encoder (not shown). The data is transmitted to the host computer 40 via the host computer 40.

An optical system unit 24 includes an optical system 25 such as an objective lens for forming an image of the object 10 on an image forming surface, a CCD camera 26 disposed on the image forming surface of the optical system 25, and an epi-illumination device. The optical system 27 and the like are housed. CCD camera 2
6 is an object 1 imaged on an image plane by the optical system 25
It captures an image of 0 and outputs an imaging signal (electric signal) to an imaging control unit 32 in the interface unit 30 described later. The CCD camera 26 includes a host computer 40
The imaging control unit 32 in the interface unit 30 described later controls an imaging enabled state, an imaging stop state, and the like based on a control signal (command) from the CPU. As an image pickup device for the object 10, an image pickup tube other than a CCD camera may be used, or a one-dimensional image pickup device (a so-called line sensor) may be used when picking up an image with a very large number of pixels. It is. In the case of using the latter line sensor, it is necessary to move the XY stage 22 so as to sequentially read the image of the object one line at a time while relatively moving the object 10 and the line sensor.

In the imaging unit 20, the base 21
Is provided with a transmission illumination optical system 28. Then, the target object 10 is irradiated with light from a light source (not shown) in the light source unit 60, which will be described later, from above in FIG.
The light is illuminated by transmitted light from below through the optical system 8, and an image of the object 10 is formed on an image forming plane by the optical system 25 in the optical system unit 24.

The light source unit 60 outputs incident or transmitted illumination light to the image pickup unit 20 via an optical fiber or the like. The light source unit 60 includes a light source and is capable of adjusting the amount of light. An optical system for guiding light to the optical fiber. The selection of the epi-illumination and the transmitted illumination and the adjustment of the light amounts of these lights are controlled by a control unit 31 inside the interface unit 30 described later.

The interface unit 30 includes a control unit 31 and an imaging control unit 32. The control unit 31 receives a control signal from the host computer 40, controls the linear actuator of the XY stage 22 to move the XY stage 22, selects epi-illumination, transmission illumination, and outputs from the light source unit 60. This is a component for controlling the amount of light, and is composed of a microprocessor and its firmware.

As described above, the imaging control unit 32 controls the C based on the control signal (command) from the host computer 40.
It controls the image capturing enabled state and the image capturing stopped state of the CD camera 26, and converts the image capturing signal from the CCD camera 26 into a monochrome 256
A / D conversion is performed with the gradation, and the image data is output to the host computer 40 as image data (one byte per pixel).

In the present embodiment, the host computer (hereinafter, referred to as a “computer”) 40 is configured using a personal computer that operates on a predetermined operating system that can be operated by a pointing device such as a mouse. And a keyboard 42a and a mouse 42b as input devices and a display 43 as an image display device.

The computer main body 41 includes a microprocessor 41B, a memory 41D, a keyboard interface (keyboard controller) 41H for connecting a keyboard 42a and a mouse 42b, and a display 43.
, A video interface 41J, a serial interface 41L, a hard disk 41P, and an image input board 41R.

The microprocessor 41B loads a control program stored in the hard disk 41P into the memory 41D and starts the program, thereby transmitting a control signal to the control unit 31 of the interface unit 30 via the serial interface (RS232C) 41L. Controls the linear actuator of the XY stage 22, the magnification control of the optical system 25, the light amount control, and the like. These settings can be stored in the hard disk 41P. The microprocessor 4
1B controls imaging by the CCD camera 26 via the image input board 41R and the imaging control unit 32, and
The imaging signal from the CD camera 26 is A / A
The image data 51B obtained by the D conversion is stored in a memory 41D.
The image data of each pixel is stored as an array element using an array prepared in advance. Therefore, in the memory 41D, image data as image information including 256-level gradation information of each pixel and position information (array information) is stored.

The hard disk 41P stores various programs for performing various image processing / measurement processing on image data of the measuring object 10, such as edge (contour) detection and pitch measurement, and includes a microprocessor 41B.
In this example, the image processing / measurement processing is performed by loading these programs into the memory 41D and starting the programs.

The microprocessor 41B sends a control command to the video interface 41H and transfers image data 51B in the memory 41D and information on the result of image processing / measurement processing to the display 43 via the video interface 41J. The image of the object 10 and the result of the image processing / measurement processing are displayed in a predetermined area (window) on the display screen of the display 43.

In FIG. 1, the image data 5 is stored in the memory 41D.
1B is stored, a program 53B for inputting measurement conditions, a program 53D for edge detection,
Program 53F for shape recognition, program 53H for measurement, program 53 for mark position movement
The state where J and the operating system 53L are loaded is shown. Program 5 for edge detection
3D is a first edge detection program 5 which will be described in detail later.
3D1, a second edge detection program 53D2, and a third edge detection program 53D3. Of course, each of the above programs can be constituted by one execution module (or execution file). However, any of a plurality of programs can be constituted by one execution module or all can be constituted by a single execution module. It is possible. The configuration depends on the operating system,
What is necessary is just to determine based on a development language etc. When the operating system 53L has management functions such as a display management function and an input / output management function, each program calls this function to perform display, input / output, and the like.

The feature of the present embodiment is that various processes are performed using the above-described programs, and therefore, these programs will be briefly described below.

Program 53B for inputting measurement conditions
The mouse 42b (or the keyboard 42a) is displayed when a menu of measurement conditions (displayed by a task bar, a toolbar, a tool box, or the like) on the display screen of the display 43 and an image of the image data 51B in the memory 41D are displayed. By detecting the position of the mouse cursor (or graphic cursor, cursor) by the operation of, the measurement conditions such as the magnification of the optical system 25, selection of transmitted illumination / epi-illumination, adjustment of the illumination light amount, and the display on the display screen of the display 43 This is a program for inputting an instruction of a measurement place, an instruction of an edge detection process, an instruction of a measurement process of a geometric shape, and other measurement conditions on the obtained image. In the present embodiment, a point input unit and a measurement condition input unit are realized by the mouse 42b (and the keyboard 42a) and the program 53B for inputting measurement conditions.

The first edge detection program 53D1 is
It is activated by instructing an edge detection process in a menu of measurement conditions displayed on the display screen of the display 43, and is input with a point (measurement start point) by an input device such as a keyboard 42a and a mouse 42b. The detection mode or the second detection mode is selected, and the instructions and the selected contents are stored in a program 53B for inputting measurement conditions.
The following programs are respectively executed in accordance with the selection of the mode when the input is made by the user. That is, when the first detection mode, that is, the vector search mode is selected, the program 53D1 is a point that satisfies a predetermined condition among the points on the edge existing near the designated point, for example, The coordinates of the nearest point on the edge (one point on the contour of the image of the object 10; hereinafter, appropriately referred to as an “edge point”, an “edge position”, or an “edge position”) are obtained by a vector search described later. Detection is performed based on image data 51B of the object 10 in the memory 41D (this image data includes 256-level gradation information and position information for each pixel), and a second detection mode. That is, when the area search mode is selected, an area search described later is performed for a predetermined range centered on the designated point, and an object within the predetermined range is searched. Based on 0 image data is a program that detects the coordinates of the edge points existing closest to a point that is the instruction. The predetermined condition may be, for example, on the sharpest edge, on the edge changing from light to dark, on the edge changing from dark to light, or on the manually designated edge, in addition to the nearest neighbor.

In the first detection mode, the program 53D1 detects edges using a plurality of straight lines in a plurality of detection directions centered on the designated designated point, and determines the coordinates of the nearest edge point to the designated point. Detect as coordinates (perform vector search). In the case of the second detection mode, among the edge points detected and detected within a predetermined range centered on the specified point, the coordinates of the edge point closest to the specified point within the range are determined. Edge detection is performed by using the edge coordinates. Further, in the case of the present embodiment, at the time of detecting the edge, the edge point is detected by differentiating the gradation information of each pixel of the image data 51B, or each pixel of the image data 51B is binarized into black and white. It is possible to set whether edge points are detected.

The second edge detection program 53D2 is
It starts when the first edge detection program 53D1 ends. In this program 53D2, in any case of the detection mode and the setting, the edge point at which the edge coordinates are detected based on the position information and the gradation information of each pixel indicated by the image data in the memory 41D is used as a reference point. Set a plurality of lines in the direction connecting the designated point and the reference point within a predetermined range including the reference point, obtain a point on the edge for each line, and set a reference point for each line from the obtained points. By obtaining the coordinates of the shortest point, the coordinates of a plurality of adjacent edge points are detected. In addition, this program 5
3D2 recognizes a straight line element based on the coordinates of the plurality of detected edge points, and normalizes the straight line element based on the linear element and a gradation change of a pixel existing on a line in a direction including the reference point. A vector is obtained, and the caliper (the range, position,
Mark indicating the direction) is set at the position of the reference point. Third edge detection program 53D3
Is started when the second edge detection program 53D2 ends. The program 53D3 detects an edge point based on a gradation change of a pixel included in the range of the set caliper, and obtains the coordinates of the point.

The programs 53D1, 53D2
, 53D3 can be detected from the optimum edge for the measurement purpose by the edge detection processing condition set by the program 53B for inputting the measurement condition. Details of this will be described later.

In the present embodiment, the first edge detecting means is realized by the first edge detecting program 53D1 included in the edge detecting program 53D, and the second edge detecting means is realized by the second edge detecting program 53D2. Has been realized.

Program 53F for shape recognition
Recognizes the type of the edge element to which the three points belong based on the coordinates of at least three adjacent edge points detected by the program 53D for edge detection, so that at least a part of the measurement object 10 is recognized. This is a program for recognizing a shape, which implements a shape recognizing unit. In the present embodiment, the program 53F divides the recognized shape of the target object 10 into a figure (hereinafter, referred to as a “geometric shape”) that can be geometrically represented as a straight line, a circle, or an arc. It also has a function of converting the information of the shape into a file containing the code and position information of each figure and storing the file in the memory 41D and the hard disk 41P. The setting of such a function is performed by selecting a measurement condition menu (displayed by a task bar, a toolbar, a tool box, or the like) displayed on the display screen of the display 43 with the mouse 42b, and by using the program 53B for inputting measurement conditions. Done. As described above, by dividing the shape of the recognized object 10 into elements and storing information on the element-divided shape, not only the data amount is reduced, but also the object 10 is designed and designed by CAD or CAM. If it is manufactured, it is easy and quick to calculate an error by comparing it with a design value on a computer.

The program for measurement 53H is a program for recognizing a shape when a certain geometric shape is selected from a menu on the display screen with the mouse 42b and an instruction of the geometric shape is inputted by the program 53B for inputting measurement conditions. Is a program for executing measurement of a parameter of a geometric shape corresponding to the instruction from the shape of the target object 10 recognized by the program 53F. The geometric shape includes, for example, a straight line, a line segment, a circle, a polygon, and the like, and the measurement contents include a length, a distance, an angle, an area, and the like. The measurement result is displayed in a predetermined area (box in the window) of the display screen of the display 43.

As will be described later, the program 53H is used to move the caliper with the mouse 42b or the like in the program 53J for moving the mark position.
Using the second edge detection program 53D2 and the third edge detection program 53D3 as child processes, the calipers are set by the program 53D2.
The function of detecting in real time the coordinates of an edge point within the range of edge detection indicated by the caliper by 3D3 and displaying the edge coordinates in a predetermined area (box in a window) of the display screen of the display 43 is also provided. Have. Further, this program 53H operates in parallel with the program 53J for moving the mark position, and calculates in real time the distance between a plurality of edge points detected within the range of edge detection indicated by the caliper. To display in a predetermined area (box in the window) of the display screen of the display 43. In this embodiment, the program 53H implements a measuring unit and a real-time detecting unit that execute measurement of an arbitrary geometric shape.

Program 53J for moving mark position
Is a program for moving the caliper, which is a mark indicating the target range, position and direction of edge detection displayed on the screen, to a desired position designated by the mouse 42b or the like. And program 53
A mark position moving means is realized by J.

Each of the above programs 53D, 53F, 53
H, 53J, the processing of edge detection and normal vector detection, shape recognition, geometric shape measurement, caliper movement, real-time detection and display, and the like, will be described in further detail later.

Next, the operation of the image measuring apparatus according to this embodiment configured as described above will be described.

First, the object 10 is placed on the XY stage 22, and the input device of the computer 40 is operated to set lighting conditions and the like for imaging the object 10 and then to set the start of imaging. By setting the start of the imaging, the imaging control unit 32 controls the CC based on the control signal from the computer 40.
The D camera 26 is set to a state in which imaging is possible. An image of the object 10 within the imaging range is captured by the CCD camera 26, and the image signal is A / D converted by the imaging control unit 32 and output to the host computer 40 as image data.
B is stored in the memory 41D as described above. Then, the image data 5 in the memory 41D is transferred from the microprocessor 41B via the video interface 41J.
An image of the target object 1B is displayed in a predetermined area (window) of the display screen of the display 43.

While looking at the image of the object 10 based on the image data 51B displayed on the display 43, the operator detects the edge detection processing and its detection mode of the measurement condition menu displayed on the display 43 by the mouse 42b or the like. (First detection mode or second detection mode)
Selection and points (the object 10 displayed on the display screen)
An operation of inputting measurement conditions such as an instruction of a point (measurement start point) near the contour of the image is performed. Thus, the above measurement conditions are input by the program 53B for inputting measurement conditions. By inputting the measurement conditions, a program 53D for edge detection, a program 53H for measurement, and a program 53J for moving the mark position are activated.
Then, edge detection is started by the program 53D for edge detection.

(In the case of setting the vector search) In the edge detection, the edge is first detected by the first edge detection program 53D1. FIG. 2 is a diagram illustrating a line in a first detection mode, that is, a search direction of a vector search. In FIG. 2, the center point P is the point designated by the mouse 42b.

There are 12 search directions from directions 1 to 12, and straight lines 1-7, 2-8, 3-9, 4-10, 5-
Edge detection is performed sequentially in the order of six straight lines 11, 6-12 in the positive and negative directions. For example, when detecting the straight line 1-7, the first edge detection program 53D1 sequentially stores the image data of the points (pixels) located on the line in the direction 1 with respect to the point P specified by the mouse 42b or the like. And calculates the luminance (gradation) indicated by the image data and its differential value (change rate of luminance (gradation)). In this case, if there is a maximum point or a minimum point in the luminance differential value, the position of that point is set as an edge point. Next, also in the direction 7, the luminance (gradation) indicated by the image data of the point (pixel) located on the line in that direction and its differential value (luminance (gradation))
Is calculated, and an edge point is searched. And
Edge detection is sequentially performed on the straight lines 2-8,..., 6-12 in the same manner as described above.

Now, description will be made assuming that there is an edge in the direction 4 in FIG. FIG. 3A is a diagram showing a state in which the caliper S is set as described later. Hereinafter, for the sake of convenience, the above-described detection of the edge position will be described with reference to FIGS. 3B and 3C. The principle will be described in more detail. The straight line in the direction 4 in FIG. 2 corresponds to the three lines in FIG.

When the search in the direction 4 in FIG. 2 is performed, that is, when the search is performed along the three lines in FIG. 3A, the change in luminance indicated by the image data as shown in FIG. A change in the differential value of the luminance is detected. In this case, as is clear from FIG. 3B, a change is shown in which the luminance increases when the object 10 (the image 10 ′) is present, and the differential value of the luminance changes from dark to bright. When the maximum point M is shown,
On the contrary, when it changes from light to dark, it indicates the minimum point M '. In this case, the point P indicated by the mouse 42b or the like
A local maximum point M is nearby (on the left side of FIG. 3A), and the coordinates of this maximum point M are detected as edge coordinates.

As described above, for the coordinates of the edge position obtained for each search direction, the distance to the coordinates of the point designated by the mouse 42b or the like is calculated. Then, the coordinates of the point having the shortest distance, that is, the coordinates of the edge point existing closest to the point designated by the mouse 42b or the like are detected as edge coordinates. As a result, the position of the edge is obtained with high accuracy on a gray scale.

As described above, when the edge coordinates which are the coordinates of the edge point which is present closest to the point designated by the mouse or the like are obtained, the second edge detection program 53D2 is started. The program 53D2 sets a predetermined small rectangular area (edge position detection area) to be subjected to edge detection centered on the edge point. The mark (mark) indicating the range, position, and direction of the “edge position detection area” on the image is a caliper, and the search length, which is the length of one side, and the length of the other side are The projection length, which is the length, can be set in the program 53B for inputting measurement conditions, and a preset value is used. At the same time as the setting of the “edge position detection area”, the corresponding caliper S is displayed on the display screen of the display 43 by the program for measurement 53H. Since the calipers correspond to the edge position detection areas on a one-to-one basis, the edge position detection areas are also referred to as calipers as appropriate. The angle of the caliper S at this time coincides with the search direction in which a point corresponding to the detected edge coordinates is obtained.

When the setting of the caliper S and the edge position detection area displayed by the caliper S is completed as described above, the second edge detection program 53D2 executes the normal vector calculation process as follows. Do.

Here, as shown in FIG.
An edge point M is detected in the direction of 4 in FIG.
The following describes a case where the caliper S is set centering on. In the case of the caliper S shown in FIG. 3A, the length in the left-right direction is the search length, and the up-down direction is the projection length. Second edge detection program 5
3D2 detects an edge point on the basis of a differential value of luminance of a pixel on a line set in the search length direction. A plurality of lines can be set in the direction of the search length, and the projection length corresponds to the number of lines.

In this case, as is apparent from the change in the luminance and the change in the differential value of the luminance in FIGS. 3B and 3C which are the search results of the third line in FIG. The general direction of the edge normal vector is direction 4.
Here, the direction of the normal vector of the edge is defined as going in the bright direction of the edge.

For each of the lines 1, 2, 4, and 5 in the area indicated by the caliper S in FIG. 3A, the gradation of the image data of each pixel is the same as in the detection of the edge coordinates M described above. (Brightness) and edge position detection based on changes in the gradation differential value (change rate). Thereby, FIGS. 3 (b) and 3 (c)
The data indicating the change in the luminance and the change in the differential value of the luminance for each of the lines 1, 2, 4, and 5 as in the case of the three lines are obtained, and the edge positions m1, m2, m4, m5, and m
The coordinates of 1 ', m2', m4 ', and m5' are obtained. Then, by detecting the coordinates of the shortest edge point at the origin (reference point) M for each line, the edge points m1, m
The coordinates of 2, m4, and m5 are obtained. These edge points are minute portions of the outline of the image 10 ′ of the object 10 near the point P specified by the mouse 42b or the like, and are least squared from the coordinates of the obtained edge points m1, m2, m4, m5, and M. A straight line or the like is calculated, and the slope of the least-squares straight line is calculated to obtain a correct normal vector V at the edge point M.
Direction is required. Since the coordinates of the adjacent (or continuous) edge positions are used in obtaining the normal vector, the processing speed is increased. When the normal vector at the edge point M is obtained as described above, the caliper S is rotated on the display screen around the point M in accordance with the direction, and set in the same direction as the correct normal vector. 43 is displayed on the display screen.

When the above processing is completed, the third edge detection program 53D3 is started. Program 53D3
Reads out image data corresponding to the range of the set caliper S from the memory 41D, calculates the luminance (gradation) indicated by the image data and its differential value, and sets the maximum point or the minimum point of the differential value to an edge. It is detected as a point, the coordinate value of the point is obtained, and stored in the memory 41D as edge coordinate data 51D (see FIG. 1). Since the edge point is detected by the caliper S set in the normal direction of the edge, the coordinates of the edge point can be obtained with high accuracy. In this case, depending on the shape and surface condition of the measurement object, a plurality of local maximum points,
Since the minimum point is detected, the program 53D3 also has a function of selecting a point on the edge that is optimal for the measurement purpose.

FIG. 12A shows such a measurement target 60.
FIG. 12B shows a differential value of luminance (gradation) indicated by the image data of the measurement object. Measurement object 60
Are slopes 61, 61 'at the left and right ends thereof and a slot 62
And In FIG. 12A, reference numerals 61a and 61
b, 61a 'and 61b' are ends of the slope, respectively.
Reference numerals 62a and 62b denote side surfaces of the long hole 62, respectively. Reference numeral 63 denotes a scratch (groove) on the surface. A point M is a reference point detected by the first edge detection program 53D1, a vector V is a vector detected by the second edge detection program 53D2, and S shown by a broken line is a second edge detection program 53D.
D2 is the caliper set. The differential value shown in FIG. 12B indicates the maximum value or the minimum value at the ends of the slopes 61, 61 ', the side surface of the long hole 62, and the position of the flaw 63.
FIG. 12A shows the local maximum value and the local minimum value in FIG.
Are assigned to the corresponding positions. These positions are
Both are edges.

In the program 53B for inputting measurement conditions, a condition for selecting an edge point detected by the third edge detection program 53D3 from the positions of these maximum values and minimum values according to the purpose of measurement can be set. I can do it.

For example, the edge point at the end of the caliper S closest to the point M (or the end opposite to the point M), ie, 61a
(61a ') is detected. The Nth edge point from the end of the caliper S on the side of the point M (or the opposite end), that is, 61b (61b ') if N = 2 is detected.
Edge points whose differential values are positive (or negative), that is, 61b, 6
3, 62a, 61a '(61a, 63, 62b, 61
b ′) is detected. This means that the image is light to dark (dark to light)
The edge point changes to Only the edge points whose differential values are equal to or greater than a predetermined value are detected. As a result, it is possible to prevent detection of an edge point of a small scratch having a small contrast, for example, 63. Differential value is maximum (or minimum)
An edge point that is (that is, the contrast is maximum) is detected.
It is possible to set a combination of the above.

The selection of the edge point to be detected can be applied to the detection of the edge point in the first edge detection program 53D1 and the second edge detection program 53D2.

Next, the case where the second detection mode (hereinafter referred to as "area search") is selected as the edge detection mode will be described.

(In the case of setting the area search) In this case as well, first, edge detection is performed by the first edge detection program 53D1.

In the case of an area search, the first edge detection program 53D1 first sets a search area of a predetermined area around a point designated by the mouse 42b or the like in the program 53B for inputting measurement conditions. This search area is displayed on the screen of the display 43.

FIG. 4 shows an example of the search area R. The point designated by the mouse 42b or the like is the center point P of the search area R.

The first edge detection program 53D1 sets a fine area (corresponding to one line width of the pixel width on the display screen) in the search area R in the row direction and the column direction. The edge point of the image 10 ′ of the target object 10 is detected for the elongated area (hereinafter, appropriately referred to as “segmented area”).

In this case, the above-described edge point detection is first performed for the subdivision area of the straight line (reference line) L in the row direction including the point P. Here, it is not always necessary to detect the edge points in the subdivision areas of all the lines in any of the row direction and the column direction, and the edge points may be detected at every predetermined number of pixels. good. When the detection target subdivision area is set every two pixels in the row direction, the subdivision area in the row direction for performing edge detection is indicated by a hatched portion in FIG.

FIG. 5 is a diagram conceptually showing a state of edge detection by this area search. First, as shown in FIG. 5A, an edge on the reference line L of the search area R is detected. The processing at this time is the same as the detection in the case of the vector search, and the image data of points (pixels) located on the reference line L from the point P with respect to the image 10 ′ of the object is sequentially read from the memory 41 D, The luminance indicated by the image data and its differential value are calculated, and an edge position (edge point) m10 is detected from the maximum point or the minimum point of the luminance differential value.
Similarly, detection of edge points m11, m12, m14, and m15 is performed for other subdivision areas in the row direction. Next, as shown in FIG. 5B, edge detection is performed in the column direction of the search area R to detect edge points m20 and m21.

The distance between each of the obtained edge points and the point P is calculated, the edge point having the smallest value (ie, the shortest distance from the point P) is found, and the coordinates of the point are determined by the edge coordinates. Detected as

As described above, when the edge coordinates, which are the coordinates of the edge point existing closest to the point P designated by the mouse 42b, are obtained, the second edge detection program 53D
2 starts. The program 53D2 sets an edge position detection area centered on the edge point, and the caliper S, which is a mark indicating the range, position and direction of the area, is displayed on the display screen of the display 43 by the measurement program 53H. Display above. The angle of the caliper S at this time is obtained as follows.

A vector V (x, y) is obtained from the coordinates (edge coordinates) M (x, y) of the edge point and the coordinates P (x, y) of the point P, which are the shortest distance from the point P. = M (x, y) -P (x, y) (1) A vector V is obtained, the inclination of the vector V is obtained, and the obtained inclination is defined as the caliper angle. That is, the angle U of the caliper is as follows: Angle U = ARCTAN (Vx / Vy) (Vy ≠ 0) (2) The angle of the vector V is calculated as described above by the program 53D for edge detection. The caliper S is displayed on the display screen of the display 43 with the edge coordinates M as the center position of the caliper S and the angle of the vector V as its inclination. FIG. 6 shows an example of the display.

In this case, the above area search is not always performed on the subdivision areas of all the lines in the row direction and the column direction in the search area R (in FIG. 6, two pixels in the row direction). Every other day)
Therefore, the direction of the vector V does not always match the normal direction of the edge at the edge point M.

When the caliper S is displayed as described above, the lines in the same direction as the direction of the caliper S in the edge position detection area indicated by the caliper S are obtained in the same manner as in the above-described vector search. Edge position detection is performed based on the change in the gradation (luminance) and the gradation differential value (change rate) of the image data of each pixel, and the coordinates of the shortest edge point at the point M for each line are obtained. From the coordinates of the edge point and the coordinates of the point M, the direction of the correct normal vector at the edge point M is obtained based on the least square line. Then, the caliper S is rotated around the point M on the display screen in accordance with the direction of the normal vector, and is displayed in the same direction as the correct normal vector.

When the above processing is completed, the third edge detection program 53D3 is started, and an edge point is detected in the same manner as in the case of the vector search, and its coordinates are obtained with high accuracy.

When detecting an edge, instead of setting the edge point to be detected by differentiating the gradation information of each pixel of the image data 51B, each pixel of the image data 51B is converted to a black and white binary image to detect the edge point. In the first edge detection program 53D1, first, the image data of the pixels in the search area R is binarized. FIG. 7 shows an example of the binarization. In the search area R, the location of the target image 10 ′ is “1”, and the location of the target image 10 ′ is “0”. Then, the distance between each of the points (pixels) of "1" and the point P designated by the mouse 42b is calculated, and the coordinates of the point having the shortest distance are detected as edge coordinates. Then, in the second edge detection program 53D2, a least-squares straight line is obtained based on the coordinates of the pixel having the shortest distance from the point P among the “1” pixels in each line, and the point corresponding to the edge coordinates is obtained. A rough normal vector may be obtained. By doing so, it is possible to detect the edge by calculating at a higher speed than in the case of the area search in which the gradation information of each pixel is differentiated (change rate) as described above.

In any case, by the edge search (vector search, area search) described above, the edge coordinates of the point closest to the point designated by the mouse 42b and the normal vector of the edge at the point corresponding to the edge coordinates Is calculated based on the direction of the normal vector, a caliper is set around the point of the edge coordinate, and displayed on the screen, and the coordinates of the edge point are calculated again based on the caliper. By doing so, it is possible to set the caliper in the normal direction of the edge regardless of the shape of the edge, and the reproducibility of measurement is improved.

Since the range of the edge search is not large, even if the searched portion is a circular arc other than a straight line, the normal vector obtained based on the above-described straight line approximation is not the correct normal line of the edge point M. It almost matches the vector. Information about the shape of the portion to be searched may be given, a least-square curve corresponding to the shape may be obtained, and a normal vector at the detection point M on the curve may be obtained.

Next, a program 53F for shape recognition
Will be described in detail. The third edge detection program 5
Simultaneously with or in place of 3D3, a program 53F for shape recognition is activated, and the shape of at least a part of the shape of the object 10 can be recognized. The shape recognition result is used in the measurement program 53H.

First, based on the coordinates of three or more edge points, that is, a reference point detected by the program 53D1 and at least two points adjacent to the reference point detected by the program 53D2, the edge element is calculated by the least square method or the hough transform method. Recognize the type of shape. As a method of recognizing the type of shape, a method based on the detection of the magnitude of an error from the least square shape or a method based on the hough transform can be selected. That is, in the case of the recognition method by the least square method, a least square straight line and a least square circle are obtained based on the coordinates of the three or more edge points, and the shape having the smaller residual is recognized for each. .

In the case of the method based on the hough transform, the state of the distribution of the direction of the normal vector of a straight line formed by two points arbitrarily selected from many points is monitored, and if the distribution is concentrated in a specific direction. It recognizes that it is a straight line, monitors the state of the distribution of the center coordinates of a circle composed of three points arbitrarily selected from many points, and recognizes that the distribution is a circle if the distribution is concentrated at a specific position. At this time, the more the number of edge points used in the processing, the more accurate the shape recognition, so the larger the number of search lines set by the program 53D2, the better. For example, when the number of search lines is set to four, the geometric shape (for example, a straight line, a circle, or an arc) is recognized from the coordinates of a total of five edge points including the reference point.

The program 53F for shape recognition further performs a process for accurately obtaining details of the recognized shape. In the process of recognizing the type of the shape, when an edge element in the caliper is recognized as a straight line shape, parameters of the recognized straight line are roughly obtained. Therefore, processing for further determining the parameters of the straight line is performed. If the detection method based on the magnitude of the error by the least squares method is selected, an edge position detection area (caliper) to be subjected to edge detection is located at a position on one side of the straight line recognized from the reference point and separated by a certain distance. Then, the edge in the range of the caliper and its normal direction are detected. Then, edge detection is performed while sequentially moving the edge detection location by a predetermined distance. Then, it is checked whether or not the edge point obtained by edge detection is on the straight line. If the error from the straight line is equal to or less than a predetermined value, it is regarded as a point on the straight line, and the straight line including the point is recalculated. Then, the error is calculated again. If the error is equal to or smaller than the predetermined value, the above processing is repeated for the next edge point. If the error is larger than the predetermined value, the point immediately before that is set as one end of the straight line. Then, the above processing is performed for the other end. Thus, the parameters of the straight line representing the straight line that forms a part of the shape of the object are obtained including the positions of the points at both ends. The parameters of the obtained straight line are stored in the memory 41D as geometric shape data 51C (see FIG. 1).

When the hough transform method is selected, the parameters of the straight line are obtained as follows.

In general, a straight line equation “y = ax + b”
Is “ρ = x · COSθ + y · SINθ, where ρ is
Is the length of the perpendicular drawn from the origin to a straight line, θ is the angle between the perpendicular and the x-axis) ”, and when the origin is taken as a point P, ρ and θ are the lengths of the edge normal vector. The heights and angles are adapted approximately. Here, a two-dimensional array representing a ρ-θ space of an appropriate size near this approximate value is prepared in advance, and the detected edge points (x, y) are defined as ρ, θ
Ρ-θ
Each time the trajectory indicating the relationship passes through the ρ-θ space,
A process of adding 1 to the array element of the dimensional array is performed. After drawing all the trajectories for the detected edge points in the image, the array element having the largest value is extracted. As in the case of the least-squares method, the edge point is newly detected and the number of points is increased while sequentially moving the position of the caliper, and the process is repeated until the next point does not exist near the extracted point. The array elements having the largest values are ρ and θ, and the last detected point is a point at both ends.

With any setting, a sequence of edge points on the same straight line can be obtained, and a straight line is detected.

FIG. 9 shows the first edge detection program 53.
This is an example of how a reference point is detected in a first detection mode (vector search) in D1, and a linear shape element is extracted by a program 53F for shape recognition.

When a point X near the straight line P1-P2 forming the contour of the image 10 'of the object surrounded by the points P1, P2 and P3 is pointed by a mouse, the first edge as shown in FIG. In the first detection mode, the detection program 53D1 performs edge detection by vector search radially around the point X by the mouse, and the second edge detection program 53D2 calculates the coordinates of the nearest edge point p0 to the point X. The normal vector is detected, the caliper is set, and the third edge detection program 53D3 calculates
Accurate coordinates of the edge point by the caliper are obtained. Then, the linear elements are recognized by the shape recognition program 53F based on these edge points as described above. Next, as shown in FIG. 3B, edge positions are detected in the order of points p1, p2, p3, p4, p5, and p6, which are separated by a predetermined distance from the edge coordinates p0 of the nearest point of the designated point X in order. , And similarly, points p7 and p8 in opposite directions.
, The edge position is detected in this order, and the processing for obtaining the straight line and the processing for detecting the points P1 and P2 at both ends are performed. In this way, the straight line (line segment) P1-P2 that forms the contour of the image 10 ′ of the target object is recognized, the parameters of the recognized straight line (linear equation, positions of both end points, etc.) are obtained, and are stored in the memory 41D. It is memorized.

In this manner, both ends of the straight line and the parameters of the straight line can be obtained only by pointing the vicinity of the outline (edge) of the image 10 'of the object with the mouse or the like. The same applies to the second detection mode. Just by pointing the vicinity of the contour (edge) of the image 10 ′ of the target object with a mouse or the like, the search area R is set, the edge coordinates are detected, and both ends of the straight line and The parameters of the straight line can be determined.

In the process of recognizing the type of shape of the shape recognizing program 53F, when the edge element in the edge position detecting area indicated by the caliper is recognized as a circle or an arc shape, a process of obtaining a circle parameter is performed. Is performed.

By the process of recognizing the type of shape, the radius of the circle and the position of the center are roughly obtained. First, an edge position detection area (caliper) to be subjected to edge detection is set at a certain distance in one direction on the circumference of the circle recognized from the position of the reference point, and the edge within the caliper range and its normal direction Is detected. Then, the edge detection is performed while sequentially moving the location of the edge detection by a constant distance. It is checked whether or not the edge point obtained by the edge detection is on the circumference. If the error from the circle element is less than a predetermined value, it is regarded as a point on the same circumference, and the circle is recalculated including that point. The error is calculated again. If the error is equal to or smaller than the predetermined value, the above processing is repeated for the point at the next edge detection location. If the error is larger than a predetermined value, the point immediately before that is set as a point at one end of the arc. Then, the above processing is performed for the other end. Thus, the parameters of the arc representing the arc forming a part of the shape of the object are obtained, including the positions of the points at both ends. If the arc is a closed circle, in one-way processing, the processing ends when returning to the reference point. The obtained arc parameters are stored in the memory 41D.
Is stored as geometric shape data 51C.

Also in this case, not only the detection method based on the magnitude of the error from the least square shape described above but also a method based on the hough transform method can be selected. In the case of the hough transform method, the details of the circle parameters are obtained by performing the same processing as in the case of the straight line instead of the straight line equation in the case of the straight line.

In the image measuring apparatus of the present embodiment, as described above, the image displayed on the display screen of the display 43 from the image data 51B read using the imaging unit 20 Contour (edge)
By specifying the vicinity with the mouse 42b, the coordinates of the edge closest to the position are detected, and the edge is detected based on the detected edge coordinates to recognize the shape of the object 10. Has become. Then, the coordinates of the start point and the end point of the straight line or the arc forming the contour of the object 10 can be automatically obtained. As described above, the image measurement device of the present embodiment can recognize the shape of the target object by a simple operation of pointing one point on the display screen using the mouse 42b or the like.

Various information obtained by performing processing by the program 53F for shape recognition on each element such as a straight line, a circle, and an arc constituting the image 10 'of the measurement target object, for example, The edge coordinates and the normal vector near the position and the shape information including the coordinates (both end point coordinates for a straight line, end point coordinates and center coordinates for a circular arc, etc.) are written in a predetermined format. And stored in the memory 41D (including a virtual memory) as the geometric shape data 51C, and is also stored as a file on the hard disk 41P. By reading this file, 1
For the imaged object, repeated display and measurement as described later can be performed.

As described above, since the information obtained by dividing the recognized shape into elements such as straight lines, circles, or arcs is stored, the data amount relating to the shape of the object to be measured is reduced, and the geometrical shape obtained by the measurement program 53H is used. The processing speed for executing the measurement increases.

Next, measurement by the measurement program 53H using the geometric data 51C in the memory 41D will be described. When the program 53H for measurement is started by the mouse 42b or the like, the figure displayed on the screen of the display 43 and the desired calculation / measurement contents are indicated, and the shape of the object 10 recognized by the above-described processing is indicated. The following arithmetic processing and measurement processing are performed using the information obtained by element division.

The general geometric dimensions can be obtained by calculation of “straight-line” or “circle-straight” or “circle-circle”. Therefore, when a straight line is specified, the coordinates of the intersection, the squareness, the degree of parallelism, the distance between the straight lines, and the like are automatically calculated. When a circle and a straight line are specified, the coordinates of the intersection, the shortest distance between the circle and the straight line, the distance between the center coordinate and the straight line, the coordinates of a perpendicular leg drawn from the center coordinate to the straight line, and the like are automatically calculated. You. When two circles are specified, the coordinates of the intersection of the circles and the distance between the centers of the circles are obtained. Further, when the designated graphic is a closed shape composed of a plurality of straight lines, the closed graphic is recognized from information obtained by dividing the element, and three triangles are used in accordance with the number of straight lines constituting the closed graphic. The four lines are recognized as quadrangular, and the coordinates of these vertices, the barycentric coordinates, and the center coordinates are obtained. If a plurality of closed figures composed of a predetermined number of circles and straight lines are selected, a specified shape is recognized from a previously registered number of circles and straight lines, and a predetermined output is calculated.

The above calculation and measurement results are displayed on the display 43.
Are displayed in a predetermined area (box in the window) of the display screen.

FIG. 11 shows an example of the display on the display 43 when the measurement processing for obtaining such a geometric dimension is performed on another object to be measured. When an image 10 ′ of the object as shown in FIG. 11 is displayed in a window on the display screen of the display, the mouse 42b
After specifying the geometric dimension measurement processing in the measurement program 53H, if two points 1 and 2 are designated as measurement points, the geometric shape to which those points belong, that is, each straight line, is selected from the geometric shape data 51C. The above-described straight-line calculation is performed, and the coordinates of the intersection B and the angle θ of the two straight lines are obtained. Similarly, when the two points 9, 9 ′ are indicated as measurement points by the mouse 42b, the angle of the two straight lines, the degree of parallelism,
The distance L between the straight lines is determined. Also, the four points 3, 4,
If 5 and 6 are continuously selected, a square element component is obtained.
If the two points 7 and 8 are continuously selected, the above-described circle-circle calculation is performed, and the coordinates of the intersection A of the circle and the circle are obtained. Similarly, if the two points 11 and 12 are continuously selected, the two circles are calculated. The center distance D is determined. In any of the above cases, the obtained measurement result is displayed in the window 44D on the display screen of the display 43.
Will be displayed.

If the graphic element to which the point designated as the measurement point belongs is not included in the geometric shape data 51C, the above-described processing is performed at that time, and the type of the shape of the graphic element to which the point belongs is determined. Detailed parameters are obtained, and processing for obtaining the geometric dimensions is performed. Then, the obtained geometric shape data is stored in the memory 41D.

The apparatus according to the present embodiment can also move the caliper S along the edge of the measurement target displayed on the display screen 44 and obtain the edge coordinates of the measurement target at the position of the caliper S in real time. it can. This will be described below. That is, the program 5 for the measurement process
When the real-time edge detection process is instructed by 3H, the caliper S is displayed on the display screen by the program 53J for moving the mark position according to the operation of the mouse 42b.
Every time the position is moved, a series of processing of edge detection, normal vector detection, and edge coordinate re-detection is performed by a program 53H for measurement by a program 53D for edge detection (programs 53D1, 53D2, 53D3). )
Is performed as a child process, the caliper S is displayed on the display screen so as to face the normal direction, and the coordinates of the detected edge point are obtained based on the position and direction of the moved caliper. At this time, the caliper S is displayed so as to move along the contour of the image 10 'of the object 10.

FIG. 8 shows an example of the display. Image 1 of the object 10 on the display screen 44 of the display 43
In the window 44A in which 0 'is displayed, first, a point A near the outline of the image 10' of the object 10 is designated by the mouse 42b or the like. Thereafter, when the caliper S displayed at the point A is moved to the points B, C, D, E, F, and G, the edge coordinates and the normal direction are obtained at each point, and the caliper S is in the direction indicated by the arrow. The edge point is detected based on the luminance change of the pixel within the range of the caliper, and the coordinates of the point are obtained. In addition, the luminance distribution in the normal direction passing through the center of the caliper S is displayed in the window 44B and the points A, B, C, D, E, F, and G at each movement position of the caliper S by the measurement program 53H. The coordinates of the edge at each point are displayed in the window 44C. The window 44D is a part for displaying the measurement result, which will be described later.

As described above, as the caliper S is moved, the coordinates of the edge point are detected in real time, and the edge coordinates are displayed on the screen. At that time, since the caliper S is also displayed, the target range of the edge detection can be easily grasped, and the use becomes easy. Also, caliper S
Is displayed in real time on the screen in the same direction as the normal vector, so that it is possible to confirm in which direction the measurement is being performed, and to obtain the edge coordinates based on the caliper S set in the normal direction. Therefore, coordinates can be obtained with high accuracy.

Further, the measurement program 53H of the apparatus according to the present embodiment has a function of real-time measurement processing of an arbitrary geometric shape in accordance with the movement of the caliper by the mouse 42b.

FIG. 10A shows the state of measurement in this case. In the window 44A in which the image 10 'of the object is displayed on the display screen 44 of the display 43, after the real-time measurement processing is designated by the measurement program 53H, first, a point K on the outline of the object is designated.
1, caliper S by mouse 42b etc. to pass through K2
Is moved to indicate the measurement position. In this case, it is preferable to set the projection length of the caliper S to be longer. Then, as shown in FIG. 10B, which is an enlarged view of the portion to be measured in FIG. 10A, a plurality of edge points k1 to kn are detected near the point K1 in the caliper S. Similarly, in the caliper S, a plurality of edge points k1 'to kn' are detected near the point K2.

Then, the detected edge points k1 to kn, k
Using 1 'to kn', shape recognition processing by the least square method or the hough transform method described above is performed to recognize the type of shape of the graphic element to which the points K1 and K2 belong (in this case, a straight line). In this case, the point used for the shape recognition process is the caliper S
, The number of data is small, and the shape recognition is completed in a short time.

Then, the line-line calculation is started using the information on the line element obtained by the shape recognition processing, and the calculation / measurement result is displayed. Representative points of the shape in the caliper, for example, detected points k1 to kn, k1 'to
kn ′ The coordinates of each average point (K11, K12) are shown in the window 44C in the parallelism, distance, angle, squareness, etc. of two straight lines (the contour of the object passing through the point K11 and the contour of the object passing through the point K12). Represents the line K11-K1 in the window 44D.
2 are displayed in the window 44B. Similarly, when the caliper S is moved so as to pass through the points K3 and K4 on the contour of the object 10, and the measurement position is designated,
The same process is performed for points K3 and K4, and the result is displayed. Thus, the result of measurement of the geometric shape can be obtained by a simple operation of designating the shape with a mouse or the like. Also, points K1, K2, on the contour of the object 10
The distance between K3 and K4 is calculated and displayed in real time.
The distance between points can be easily measured. In addition, since the caliper is displayed in real time on the screen in the same direction as the normal vector, it is easy to grasp in which direction the measurement is being performed. After detecting the points k1 to kn and k1 'to kn', the shape may be recognized by referring to the geometric shape data 41C.

As described above, when the indication of the measurement location is performed using the caliper with the mouse, the various measurements described above based on the image of the object can be automatically performed only by moving the caliper. In addition, the caliper is set to pass only one point on the contour, the length of a perpendicular to a straight line arbitrarily selected from points detected by the caliper, or the distance between the point and the arbitrarily selected point, or It is also possible to calculate and display an angle with an arbitrarily selected straight line including the arbitrary point as an end point in real time. In such measurement, when the coordinates (x, y) of a certain edge point on the object are detected, the coordinates are converted into polar coordinates (r, θ) having an arbitrary selected point on the object as the origin. Can be easily performed.

As described above, according to the image measuring apparatus of the present embodiment, various measurements can be performed based on the image 10 'of the target object 10 by a simple operation of designating a measurement location with the mouse 42b. it can.

In the above embodiment, the case where the search direction in the vector search is set to 12 directions has been described. However, the present invention is not limited to this, and the number of the search directions can be increased. Needless to say, the detection accuracy increases as the number increases. Also, the normal vector of the detected edge is assumed to take a direction in the bright direction of the edge,
It goes without saying that the direction may be reversed.

Furthermore, in the above-described embodiment, the case has been described where the arithmetic operation such as the measurement process is performed by the microprocessor using a program. However, the present invention is not limited to this, and the process is performed using a digital signal processor (DSP) or the like. You may do it.

In the above embodiment, the case where image data obtained by imaging with a CCD camera is stored in a memory as it is and various measurement processes are performed using this image information has been described. Without being limited to, for example, image information of the object obtained by imaging in advance is recorded on an information recording medium such as a floppy disk, a magneto-optical disk, and the information recorded on this recording medium is recorded in a memory.
The various measurements described above may be performed using this information.

[0113]

As described above, claims 1 to 5
According to the invention described in (1), there is an unprecedented superior effect that the edge detection and the shape recognition of the measurement target can be performed by a simple operation of inputting a point instruction.

In particular, according to the second aspect of the present invention, in addition to the above-described effects, the result of measuring the geometric shape can be obtained by a simple operation of inputting an instruction of an arbitrary geometric shape. There is also.

According to the sixth aspect of the present invention, the coordinates of a point on the edge included in the target range of the edge detection by the mark are obtained in real time, and the coordinates of this point are displayed on the screen. This has the effect that the position of the edge coordinates in the mark can be immediately recognized.

Further, according to the invention of claim 7, there is an effect that various measurements based on the image of the object can be automatically performed only by moving the mark.

According to the eighth aspect of the present invention, since the mark is displayed in real time on the screen in the same direction as the normal vector, it is possible to easily grasp in which direction the measurement is being performed. There is.

[Brief description of the drawings]

FIG. 1 is a diagram showing an image measuring device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a search direction when a first detection mode is set.

3A is a diagram illustrating a state in which a caliper S is set, and FIG. 3B is a diagram illustrating luminance of image data of a pixel on a line when a search in a direction 4 is performed on three lines in FIG. (C) is a diagram showing a change in a differential value of luminance.

FIG. 4 is a diagram illustrating a search area.

5A and 5B are diagrams illustrating positions of edges found by edge detection, wherein FIG. 5A is a diagram illustrating a state in which a plurality of edge points are obtained in a row direction of a search area R, and FIG. FIG. 14 is a diagram illustrating a state in which a plurality of edge points are obtained in the column direction of R.

FIG. 6 is a diagram illustrating a display example of a caliper set with edge coordinates as a center position.

FIG. 7 is a diagram illustrating binarization of image data in a search area R;

FIG. 8 is a diagram illustrating a state in which a caliper S moves along the contour of an image 10 ′ of a target object.

FIGS. 9A and 9B are diagrams illustrating an example of extracting a linear shape element after edge detection in the first detection mode ((a) and (b)).

10A is a diagram for explaining an example of real-time measurement processing of an arbitrary geometric shape by a measurement program, and FIG. 10B is an enlarged view of a measurement target portion of FIG.

FIG. 11 is a diagram illustrating an example of a display on a display when measurement processing for obtaining a geometric dimension is performed on another measurement target object.

12A is a plan view illustrating an example of a measurement target to be subjected to edge point detection, and FIG. 12B is a diagram illustrating a differential value of luminance (gradation) indicated by image data of the measurement target in FIG. FIG.

[Explanation of symbols]

Reference Signs List 10 Measurement object 41D Memory 42a Keyboard (part of measurement condition input means) 42b Mouse (part of point input means, part of measurement condition input means, part of mark position moving means) 43 Display (display device) 51B Image data (image information) 53B Program for inputting measurement conditions (part of point input means, part of measurement condition input means) 53D1 First edge detection program (first edge detection means) 53D2 Second edge Detection program (second edge detection means) 53F Program for shape recognition (shape recognition means) 53H Program for measurement (measurement means, real-time detection means) 53J Program for mark position movement (of mark position movement means) Partial) P reference point S Caliper (mark)

Claims (8)

[Claims] 1. An image measurement device for measuring a shape of a measurement target using image information obtained by capturing an image of the measurement target, wherein: a memory for storing the image information; An image display device for displaying an image corresponding to the image on a display screen; point input means for inputting an instruction of a point near a measurement point on the image displayed on the display screen; Based on the position information and the gradation information of each pixel included in the image information, a predetermined condition among a plurality of points on the edge of the image of the object existing near the point designated by the point input means is determined. First edge detecting means for detecting edge coordinates which are coordinates of a point on the edge to be satisfied; and the specified point within a predetermined range including a point on the edge at which the edge coordinates are detected as a reference point; Multiple lines in the direction connecting the reference point For at least two lines other than the line including the reference point of the plurality of lines, on the edge based on the position information and the gradation information of each pixel included in the image information in the memory for each line. Second edge detecting means for detecting the coordinates of the point; an edge to which the three points belong based on the coordinates of at least three points on the edge which are detected by the first and second edge detecting means and which are close to each other. An image measurement device comprising: shape recognition means for recognizing at least a part of the shape of the measurement object by recognizing a type of an element. 2. The apparatus according to claim 1, further comprising: a measurement condition input unit for inputting an instruction of an arbitrary geometric shape; and a measurement unit for performing a measurement process for obtaining the geometric shape specified by the measurement condition input unit. 2. The image measuring apparatus according to claim 1, wherein the calculating unit obtains a parameter of a geometric shape corresponding to the instruction from the shapes recognized by the shape recognition unit. 3. An image measurement device for measuring a shape of the measurement object using image information obtained by capturing an image of the measurement object, wherein: a memory for storing the image information; An image display device for displaying an image corresponding to the image on a display screen; point input means for inputting an instruction of a point near a measurement point on the image displayed on the display screen; Based on the position information and the gradation information of each pixel included in the image information, a predetermined condition among a plurality of points on the edge of the image of the object existing near the point designated by the point input means is determined. First edge detecting means for detecting edge coordinates which are coordinates of a point on the edge to be satisfied; and the specified point within a predetermined range including a point on the edge at which the edge coordinates are detected as a reference point; Multiple lines in the direction connecting the reference point For at least two lines other than the line including the reference point of the plurality of lines, on the edge based on the position information and the gradation information of each pixel included in the image information in the memory for each line. Second edge detecting means for detecting the coordinates of a point, wherein the second edge detecting means recognizes a straight line element based on the edge coordinates of the reference point and the coordinates on at least two edges near the reference point. A function of obtaining a normal vector of the linear element based on the linear element and a gradation change of a pixel existing on a line in a direction connecting the designated point including the reference point and the reference point. An image measurement device, further comprising: 4. The method according to claim 1, wherein the first edge detecting means includes position information and gradation information of pixels existing on a plurality of radial lines in the search direction centered on the designated point designated by the measuring condition input means. 4. A method according to claim 1, wherein points on a plurality of edges are detected based on the coordinates, and coordinates of a point having a shortest distance from the designated point among these points are detected as edge coordinates. The image measurement device according to claim 1. 5. The first edge detecting means sets a plurality of lines in a row direction and a column direction within a predetermined rectangular range centered on a point designated by a point input means, and For each of the lines, and for at least two lines other than the line, an edge based on the position information and the gradation information of each pixel included in the image information in the memory for each line. 4. The coordinates of an upper point are detected, and coordinates of a point having the shortest distance from the designated point among these points are set as edge coordinates.
The image measurement device according to any one of the above. 6. An image measurement apparatus for measuring a shape of the measurement object using image information obtained by capturing an image of the measurement object, wherein the memory stores the image information; An image display device for displaying an image corresponding to the above on a display screen; and mark position moving means for moving a mark indicating a target range, a position and a direction of edge detection displayed on the screen to a desired position; An image measurement apparatus comprising: a real-time detection unit that obtains, in real time, coordinates of a point on an edge included in a target range of edge detection by the mark as the mark moves. 7. The method according to claim 7, wherein the real-time detection unit is configured to determine a plurality of points on an outline of the measurement target based on coordinates of points on an edge included in a range of the edge detection target area while the mark is moving. The distance between, the length of the perpendicular to an arbitrarily selected straight line or the distance to an arbitrarily selected point, or the arbitrarily selected straight line including the arbitrarily selected point as an end point and a point on the edge 7. The image measuring apparatus according to claim 6, further comprising a function of obtaining an angle formed by a straight line in real time. 8. The real-time detecting means obtains, in real time, a normal vector of a point on the edge from which the coordinates have been obtained, and sets the angle of the moving mark in the same direction as the normal vector to display on the screen. The image measurement apparatus according to claim 6, further comprising a function of displaying the image in real time.