JPH10320565A - Image processing method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing method and a device capable of easily and accurately image-processing the image of an object of a size exceeding an image pickup visual field and obtaining prescribed data. SOLUTION: The image is picked up for plural times in visual fields G1, G2, and G3, where the objects are mutually continuously or partially overlap by relatively moving an image pickup device and the object 10. Based on the arithmetic result of the respective center positions C1 and C2 of the object obtained by an image processing in one visual field and the next visual field and a relative moving amount (Xoff) between the image pickup device and the object at the time of moving to the next visual field, the center position of the object in a visual field corresponding to the visual field, for which one visual field and the next visual field are put together is obtained. By repeating the processing until the entire scene of the object is put in, the center position of the entire object is obtained. Since the center position of the object corresponding to a composited visual field is obtained without compositing the entire images of the object in the respective visual fields later, the capacity of a memory for storing the image data is substantially saved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing method and apparatus, and more particularly, to an image processing method and apparatus for processing image data of an object having a size exceeding a field of view of an imaging apparatus.

[0002]

2. Description of the Related Art Conventionally, in an electronic component mounting apparatus (mounter), an image of a component sucked by a suction nozzle is used as a CC.
Capture from an imaging device (image input device) such as a D camera,
By processing the image of the component, the position of the component is detected, and if necessary, the position of the component is corrected by correcting the orientation of the component by the suction nozzle, thereby mounting the component on a predetermined board.

In a system for measuring and evaluating the position of an object such as a part using image processing, when handling a large object that does not fall within the visual field range that can be imaged at a time, the visual field that can be imaged at a time is enlarged. There has been proposed a method of performing image processing, and a method of performing image processing after capturing an image of an object in a plurality of times one by one and synthesizing respective image data.

[0004]

In the above-described method for enlarging the imaging field of view, the distance between the imaging device and the target (distance between the object and the image) is changed, or the focal length of the lens of the imaging device is changed. Since mechanical changes are required, coexistence with the original system is difficult, and the resolution is reduced at the image input stage, so the resolution (accuracy) after image processing is also reduced. There is a problem that it cannot be adopted in a system that demands the system.

The method of imaging an object in a plurality of times has a disadvantage that means for storing image data, for example, a semiconductor memory must be newly provided for the number of times of imaging. Further, changes in the image processing method, such as addition of image data combining processing, also increase.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an image processing method and an image processing method capable of easily and accurately performing image processing on an image of an object having a size exceeding a field of view and acquiring predetermined data. It is an object to provide a device.

[0007]

According to the present invention, in order to solve this problem, an image processing method for processing an image of a target object picked up by an image pick-up device, the image pickup device and the target object are relatively moved. By imaging the object multiple times in a field of view that is continuous or partially overlapping with each other, an image pickup device when moving to the next field of view and each data of the object obtained by image processing in one field of view and the next field of view Based on the calculation result of the relative movement amount between the objects, a configuration is employed in which data of the object in a field of view corresponding to a field of view obtained by combining the one field of view and the next field of view is adopted.

According to the present invention, there is provided an image processing apparatus for processing an image of a target object picked up by an image pickup device movable relative to the target object. When the imaging device and the object are relatively moved so that the object is continuously or partially overlapped with each other, the image of the object imaged by the imaging device is processed to acquire data of the object before and after the relative movement. Means for calculating based on the data of the object obtained before and after the relative movement and the relative movement amount of the imaging device and the object, and matching the visual field of the imaging device before and after the relative movement based on the calculation result. A configuration for acquiring data of an object in a portion corresponding to the field of view is also adopted.

In such a configuration, instead of acquiring image data in each field of view of the imaging device and combining the image data and acquiring data of the object from the combined image, one field of view, the imaging device, and the object are obtained. The data of the object is obtained in the next field of view obtained by the relative movement of the object, and the data of the object in the field of view obtained by combining the respective fields of view is obtained based on the calculation result of the obtained data and the relative movement amount. Therefore, it is not necessary to combine images in each field of view to obtain data of the object. Therefore, it is not necessary to store all images of the object in each field of view for synthesis, and it is only necessary to store target data of the object obtained in image processing in each field of view. Significant savings in means capacity are possible. Further, since it is not necessary to combine all the image data in each field of view to obtain necessary data, the cost and time of image processing can be significantly reduced.

For example, when the data of the object is position data such as the center position of the object, the center position of the object in one field of view is obtained, and the center position of the object in the next field of view is obtained. . Since the center position of the object in the field of view combining the two fields of view can be easily calculated based on the data of the center position in each field of view and the relative movement amount of the imaging device and the object, the total position of the object in each field of view can be calculated. The center position of the object corresponding to the synthesized image can be obtained without synthesizing the images.

If the entire view of the object cannot be imaged in both fields of view, the image pickup apparatus and the object are moved relative to each other, and further moved to the next field of view. At this time, the data of the center position of the object in the previous two fields of view, the data of the center position of the object in the next field of view, and the center position of the object in the field of view obtained by combining the three fields of view with each relative movement amount Can be requested. By repeating such a process until the entire view of the object is included, the position data of the object can be easily obtained even for a large object.

Further, since the desired data of the object can be obtained by simple calculations, a large object can be handled with little change in mechanical, electrical, and software and without lowering the resolution (accuracy). It becomes possible.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1 is a diagram showing the overall configuration of an image pickup apparatus and an image processing apparatus to which the present invention is applied.

Reference numeral 1 denotes an object to be subjected to image processing, for example, an electronic component. The object 1 is placed on an XY table 5 and is imaged by an image input device that captures image data, for example, an imaging device 2 such as a television camera or a CCD camera. The image data of the object 1 captured by the imaging device 1 is subjected to image processing by the image processing device 3, and the image of the object captured by the imaging device 2 or the process of the image processing device 3 is displayed on the monitor television 4 or the like. Displayed on the device.

The XY table 5 has an X-direction moving motor 6 and a Y-direction moving motor 8 which are connected to the table top and the
Is kept parallel to the imaging surface of the camera. XY table 5
Can be detected by the encoder 7, and the position of the XY table 5 in the Y direction can be detected by the encoder 9.

In the present invention, image processing of an object having a size exceeding the visual field range of the imaging device 2 is an object.
A rectangular object (electronic component) 10 as shown in FIG.
Will be described as an example.

As shown in steps S1 and S2 in FIG. 3, a part 10a of the object is positioned in the field of view G1 (Lx
The XY table 5 is moved by the motors 6 and 8 so as to enter L), and the object is imaged. Next, image processing is performed by the image processing device 3 based on the captured image of the object (step S3). By this image processing, the object portion 10a
Is extracted.

Subsequently, in step S4, the coordinates (X1, Y1) of the center position C1 of the object portion 10a in the visual field G1 are calculated. Next, the coordinates of the center position and the coordinates of the left end X0
Is stored in the memory (step S5).

In a succeeding step S6, it is determined whether or not the entire view of the object 10 has been captured. Since only a part of the object is imaged in the field of view G1, the process returns to step S1, and the XY table 5 is driven by the motor 6 so that another part 10b of the object 10 is imaged by the imaging device 2. Move.
This movement amount Xoff can be detected by the encoder 7. In this example, the movement is only in the X direction, but in any case, the movement of the XY table 5 is such that the image before movement and the image after movement are continuously connected or partially overlapped. So that there is no gap between them.

The image data is taken in again from the image pickup device 2, the data is processed in the image processing device 3, and the contour of the object portion 10b in the next visual field G2 is extracted. And
The coordinates (X2, Y2 = Y) of the center C2 of the object portion 10b
1) is obtained and stored in the memory together with the movement amount Xoff.

In the example of FIG. 2A, since the entire scene of the object has been imaged, the data processing of the result is performed in step S7. That is, the center coordinates (Xc, Yc) of the object in the combined visual field of the visual fields G1 and G2 are obtained. Assuming that the right end coordinate of the object in the synthetic visual field is Xn, Xn = (2X1-X0) + 2X2-(L-Xoff) = 2X1 + 2X2-X0-(L-Xoff), so that Xc = ( X0 + Xn) / 2 = X1 + X2- (L-Xoff) / 2. Yc becomes Y1.

As described above, the center position of the object in one field of view G1 is obtained, the center position of the object in the next field of view G2 is obtained, and the field of view obtained by combining the two fields of view is calculated by the amount of movement. Can easily calculate the center position of the object in the above, so that the memory capacity can be remarkably saved without combining all the images of the object in each field of view.

FIG. 2B further shows the XY table as Xof.
The object 1 to which the whole view is captured in the field of view G3 after moving f
An example of 0 'is shown.

The X coordinate Xc of the center in the entire visual field is the same as the processing of the center coordinate in the composite visual field of the two visual fields G1 and G2 and the X coordinate X3 of the central position C3 in the visual field G3. Therefore, Xc = (X0 + Xn) / 2 = {X1 + X2- (L-Xoff) / 2} + X3- (L-Xoff) / 2 = X1 + X2 + X3- (L-Xoff)

In general, the center coordinate Xc of an object in a visual field obtained by combining a plurality of visual fields is given by: Xc = (sum of results in each visual field) − (1/2) (field number in X direction−1) (Length of overlapping part).

When the object is large in a rectangular shape and must be moved not only in the X direction but also in the Y direction, the Y coordinate of the center can be obtained in the same manner as the X coordinate of the center is obtained. .

In the above example, the object 10 is imaged in a plurality of fields of view, for example, two or three fields of view G1 to G3, but the number of fields of view is determined according to the size of the object. 2 (X direction) X 1 (Y direction)
Field of view, 3X1 field of view, 4X1 field of view, 2X
Fields of view such as 2 fields of view, 1 × 2 field of view, 1 × 3 field of view, 1 × 4 field of view, etc. can be selected. In that case, X,
It is preferable that the visual field distances Xoff and Yoff in the Y direction are respectively set to the same value, but they can be changed as necessary. In the case of variable, the contents of the operation do not differ, only the length of the overlapping portion changes.

Next, as shown in FIG. 4, an example will be described in which the lead tip coordinates of an object 20 (electronic parts such as ICs) having a large number of leads on both sides are obtained.

As in the previous example, steps S1, S2 in FIG.
2, a part 20a of the target object is in the field of view G1 of the imaging device.
The XY table 5 is moved to the motor 6 so as to enter (L x L).
8 to image the object portion 20a. This imaging example is illustrated in FIG. Next, image processing is performed by the image processing device 3 based on the captured image of the object (step S3).

In this image processing, a frame having a size including a lead row to be detected is set, and a filtering process (DOG) is performed in the lead width direction in this frame to detect a zero cross and detect a lead edge. , The tip coordinates (xn, yn) (n = 1, 2, 3, 4, 5) of the upper lead row are obtained. Similarly, the same processing is performed on the lower lead row, and the leading end coordinates (xn ', yn') are obtained (step S4).

Next, in step S5, necessary data is stored. The data stored in the memory is the field of view G1
The calculated lead tip coordinates (xn, yn), (x
n ', yn').

Since all of the objects 20 have not yet been captured, the flow returns to step S1 to store the XY table in Xoff, Yo.
ff (in this example, Yoff = 0) and then move to the field of view G
2 and the imaging as shown in FIG. 5B is performed.

In the same manner, the coordinates of the tip of the lead (Xn, Yn), (Xn ', Yn') are applied to the upper and lower lead rows.
(N = 5, 6, 7, 8, 9) is obtained, and each lead coordinate and offset distances Xoff and Yoff from the visual field G1 are stored in the memory.

Since the entire view of the object has been captured, the coordinates (XXn, YYn) of the lead ends of all the objects are obtained in step S7.
(XXn ', YYn') is obtained.

For n = 1 to 4, (XXn, YYn) = (xn, yn) (XXn ', YYn') = (xn ', yn')

For n = 6-9, (XXn, YYn) = (Xn + Xoff, Yn + Yoff) (XXn ', YYn') = (Xn '+ Xoff, Yn' + Yoff)

Note that, for a lead that enters both fields of view (a lead with n = 5), the average value of both coordinates is used as the lead coordinate.
For this reason, with respect to the lead row data in the overlap portion, the data of the coordinates within １ ／ read pitch are set to the same lead, and the average value is taken. In the example of FIG. 4, since the fifth lead overlaps, the coordinates of the tip are XX5 = {x5 + (X5 + Xoff)} / 2 YY5 = {y5 + (Y5 + Yoff)} / 2XX5 ′ = ｛x5 '+ (X5' + Xoff)} / 2 YY5 '= {y5' + (Y5 '+ Yoff)} / 2.

Here, the center of the upper lead row is (XX
c, YYc) and the center of the lower lead row is (XX'c, YY '
c), XXc = (XX1 + XX2 +... + XX9) / 9 YYc = (YY1 + YY2 +... + YY9) / 9XXc ′ = (XX1 ′ + XX2 ′ +. '+ YY2' +... + YY9 ') / 9.

The center coordinates of the entire object are represented by (Cx, Cx
y), Cx = (XXc + XXc ') / 2 Cy = (YYc + YYc') / 2

In each example, the center coordinate or the lead tip coordinate is obtained. However, the inclination of the object or the inclination of the lead can be obtained by a simple calculation. For example, the inclination can be obtained by a center coordinate of each part or a straight line connecting the coordinates of both ends of the lead.

In the above-described example, the data of each read row is checked, and if, for example, a defective read or a damaged read is detected, all the processing may be stopped as a recognition error. The recognition error may be stopped not only when the read row is not secure but also when an abnormality is detected in other data processing as a recognition error.

In each of the examples described above, the data processing of the result is performed after capturing the entire view, but the data of the two fields of view (center coordinates in the example of FIG. 2, coordinates of the tip of the lead in the example of FIG. 4) are combined. The combined data obtained by the processing and the data of the next field of view may be combined. In that case, the capacity of the memory can be saved.

In each embodiment, the method of moving the object while fixing the imaging device 2 has been described. However, a method of moving the image input device 2 while fixing the object is also possible.

By adding a mechanism for holding the object on the XY table 5, a method of turning the head upside down is also possible.

[0046]

As described above, according to the present invention, when an image of a large object exceeding the field of view of the image pickup device is taken and image processing is performed, all images in each field of view are combined to obtain data of the object. It is not necessary to save the target data of the target obtained in the image processing in each field of view and only a small parameter such as the relative movement amount of the target and the imaging device, so that the capacity of the storage means is significantly reduced. It is possible to save. Furthermore, according to the present invention, it is possible to easily realize an image processing apparatus that handles a large object without changing hardware or software, and without reducing the resolution (accuracy).

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an overall configuration of an image capturing processing system using the apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a process for obtaining a center position of an object.

FIG. 3 is a flowchart illustrating a flow of image processing.

FIG. 4 is an explanatory diagram illustrating a process of obtaining a tip position of a lead of an object.

FIG. 5 is an explanatory diagram illustrating a process of obtaining a tip position of a lead of an object.

[Explanation of symbols]

 1, 10, 20 Object 2 Imaging device 3 Image processing device 4 Monitor television 5 XY table 6, 8 Motor 7, 9 Encoder

Claims (6)

[Claims] 1. An image processing method for processing an image of an object imaged by an imaging device, wherein the imaging device and the object are relatively moved to image the object a plurality of times in a field of view overlapping or partially overlapping each other. Based on the calculation result of each data of the object obtained by the image processing in one field of view and the next field of view and the relative movement amount between the imaging device and the object when moving to the next field of view, An image processing method comprising: obtaining data of an object in a visual field corresponding to a visual field obtained by combining one visual field and the next visual field. 2. The image processing method according to claim 1, wherein said data is data indicating a center position of a target object or a lead tip position. 3. The method according to claim 1, wherein when an abnormality is detected in the processing of the data, the processing is stopped.
The image processing method according to 1. 4. An image processing apparatus for processing an image of a target imaged by an imaging device movable relative to the target object, wherein the image of the target imaged by the imaging device and the target object are mutually Means for processing the image of the object imaged by the imaging device when the imaging device and the object are relatively moved so as to continuously or partially overlap, and acquiring data of the object before and after the relative movement, Means for performing an operation based on the data of the object obtained before and after the relative movement and the imaging device and the relative movement amount of the object, respectively, from the calculation result to a field of view obtained by combining the fields of view of the imaging device before and after the relative movement. An image processing apparatus for acquiring data of an object in a corresponding portion. 5. The image processing apparatus according to claim 4, wherein the data is data indicating a center position of the object or a lead tip position. 6. The method according to claim 4, wherein when an abnormality is detected in the processing of the data, the processing is stopped.
An image processing apparatus according to claim 1.