JPH0560514A - Image processing device for traveling workpiece - Google Patents

Abstract

PURPOSE:To provide a highly reliable and practical image processing device for a traveling workpiece, capable of quickly detecting the workpiece on the basis of image data processing. CONSTITUTION:An image processing device has an image input control circuit 4 for sequentially outputting the data of every scanning line after receiving an image signal from an image sensor 2 to take up the image of a traveling workpiece, an image memory 5 for storing the image data for one screen after receiving an image signal outputted from the circuit 4, and an image processing circuit 6 for reading and processing image data after receipt of an access permission signal from the image memory 5. Furthermore, the device has a workpiece detection circuit 10 for sending a workpiece detection signal to the image memory 5 via the detection of the trailing end of the traveling workpiece from the level change point of image data comprising image signals extracted from a specific single scanning line or a plurality of scanning lines, among image signals serially outputted from the image input control circuit 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for processing an image of a moving work picked up by an image sensor to judge a work posture, for example.

[0002]

2. Description of the Related Art In an automatic assembly line or the like, when a part to be fed (hereinafter referred to as a work) has a direction, conventionally, during the feeding, its posture (direction) is mechanically determined by an attachment, Although a work having a defective or wrong posture was excluded by a selection mechanism, in recent years, an image sensor is used to capture an image of a moving work and the image output of this image sensor is processed to determine the work posture. The technology has come to practical use.

FIG. 3 is a block diagram showing an example of a work posture discriminating apparatus based on this type of image processing. In the figure, reference numeral 1 is a light source for illumination, which irradiates a work W on a conveying path 20 such as a conveyor from a horizontal direction that is perpendicular to the work moving direction. A two-dimensional image sensor (a CCD camera in this example) 2 captures an image of the work W illuminated by the light source 1 and outputs the image as a signal I.
In the form of an image, and sends it to the image input control circuit 4. A work position detector 3 is provided to obtain the timing when the work W enters the visual field of the image sensor 2, and a detection signal S thereof is input to an image processing circuit 6 described later. The image input control circuit 4 sequentially takes in the image signal I for one line output from the image sensor 2 in a constant cycle, converts it into image data that can be processed, and sends it to the image memory 5.
The image memory 5 stores image data for one screen. The image processing circuit 6 includes a window unit 7 and a posture determination circuit 8, and when the detection signal S arrives, the image memory 5
In response to this, an image capture start signal is given. Image memory 5
Upon receipt of this image capture start signal, starts storing the image data, and when storing one screen of image data is completed, sends an image capture completion signal to the image processing circuit 6. Upon receiving the image capture completion signal, the image processing circuit 6 reads the image data from the image memory 5 and determines the posture of the work W. In this attitude determination, the number of white pixels and the number of black pixels in the attitude determination window WINDW (shown in FIG. 4) set in the window area 7 are counted, and it is determined from the magnitude of this count value and the threshold value. Do it.

[0004]

SUMMARY OF THE INVENTION In the above conventional one,
The work position detector 3 is used in order to know that the image sensor 2 has picked up an image of the work. Since the work position detector 3 is mounted in the vicinity of the conveyance path 20, this conveyance path 20 can be used for, for example, component supply. However, in the case of a rotary feeder work feed path, there is a problem that the number of man-hours required for the mounting process and the adjustment after the mounting and the cost are high.

The present invention has been made to solve this problem, and it is highly reliable that the work can be detected quickly by processing the image data without using the work position detector. An object of the present invention is to provide an image processing device for a mobile work, which is highly practical.

[0006]

In order to achieve the above object, the present invention provides an image input control circuit for inputting an image signal of an image sensor for picking up an image of a moving work and sequentially outputting it for each scanning line. An image memory for inputting image data output from the control circuit and storing image data for one screen, and an image processing circuit for receiving image data from the image memory after receiving an access permission signal from the image memory and performing image processing In the image processing apparatus for a mobile work, the image input control circuit extracts image data of a specific one or a plurality of lines from the image data output from the change point of the level value of the extracted line image data. There is a work detection circuit that detects the rear end of the work and sends a work detection signal to the image memory. The access permission signal is sent to the image processing circuit to stop the operation of storing the image data when receiving the detection signal, and a resume configure storage operation of the image data by the access end signal of the image processing circuit.

According to a second aspect of the present invention, the work detection circuit generates a work detection signal when a change in the level value is detected after a lapse of a predetermined time from the first level value change point.

[0008]

According to the present invention, the image data of the specific line is extracted from the image data of one screen, and the change point of the value of the extracted line image data (the boundary point between the work image and the background image) is detected. Since the work detection signal is generated, the processing time can be shortened as compared with the case where the work is detected from all the image data of one screen.

According to the second aspect of the present invention, the change in the value of the line image data is conditioned on the lapse of a predetermined time after the change in the value of the first line image data. Can detect.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 10 denotes a work detection circuit, which includes a line extraction unit 11, a front end detection unit 12, a rear end detection unit 13, and a work detection unit 14. Other configurations are shown in FIG.
Is the same as

The line extracting unit 11 extracts the image data (line image data) of a specific line of the image data sequentially output to the image memory 5 by the image input control circuit 4 for each line to detect the leading end detecting unit 12 and the trailing end. The line No. of the specific line to be extracted, which is input to the unit 13, is set in advance. This image data is assumed to be black and white binary image data. As the specific line, as shown in FIG. 2, a line that completely includes the work image from the front end to the rear end of the work W is selected. The tip detection unit 12 outputs a tip detection signal when the serially input image data of the specific line changes from the value “white pixel” of the background image to the value “black pixel” of the work image. The trailing edge detection unit 13 outputs a trailing edge detection signal when the serially input image data of the specific line changes from the value “black pixel” of the work image to the value “white pixel” of the background image. When the work detection unit 14 receives the rear end detection signal after a predetermined time To (or a predetermined number of pixel intervals) after inputting the front end detection signal, it sends the work detection signal P ₁ to the image memory 5. Image memory 5
Is an image capture start signal (access end signal) P described later.
The image signal from the image input control circuit 4 is being received in response to ₃ and, when the work detection signal P ₁ is received, this storing operation is continued until the image data for one screen is completely stored. When the storage of the image data for the screen is completed, the image capture completion signal P ₂ which is an access permission signal is sent to the image processing circuit 6. As a result, the image processing circuit 6 starts access to the image memory 5, reads the image data stored therein, and when the access ends, sends an image capture start signal P ₃ to the image memory 5, and the image memory 5 inputs the image. The storage of the image data from the control circuit 4 is restarted.

As described above, in this embodiment, since the work is detected by processing the image data without using the work position detector, the above-mentioned problem, that is, the mounting is troublesome and the cost is high. Can be completely eliminated.

Moreover, since one piece of image data on a specific line is processed to detect a work, a shorter time is required as compared with the case where all image data is processed to detect a work.
The circuit and software therefor are simple, and are extremely effective in terms of practicality.

In the above embodiment, the case in which the number of specific lines to be extracted is one has been described. However, when the front and rear ends of the work image are complicated images, a plurality of specific lines are specified. Extract the line, and AND of the leading edge detection signal and the trailing edge detection signal for each specific line,
The work may be detected based on the majority rule.

Further, in the above embodiment, the work detection is performed on condition that the front end detection unit 12 receives the rear end detection signal after a predetermined time To (or a predetermined number of pixel intervals) after the front end detection signal is generated. Since the signal P ₁ is generated, erroneous detection due to noise or the like can be prevented and reliability is high.

In the above embodiment, the case of a monochrome binary image has been described, but it is obvious that the present invention can be applied to the case of a color image.

Further, in the above embodiment, the case of using the two-dimensional image sensor has been described, but the present invention can be applied to the case of using the line type image sensor to obtain the same effect.

[0019]

As described above, the present invention extracts the image data of one or a plurality of specific lines from the image data of one screen, and changes the value of the extracted line image data (work image and background). Since the work detection signal is generated by detecting the (boundary point with the image), the time required for data processing is short, and the circuit and software for that are simple, so it can be implemented inexpensively and is practical. Is excellent in

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a specific line of an image in the above embodiment.

FIG. 3 is a block diagram of an image processing apparatus including a conventional work position detector.

FIG. 4 is a diagram showing a captured image of a work.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source for illumination 2 Image sensor 4 Image input control circuit 5 Image memory 6 Image processing device 10 Work detection circuit 11 Line extraction unit 12 Front end detection unit 13 Rear end detection unit 14 Work detection unit 20 Transport path W Work

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location // B65G 47/14 Z 8819-3F G01N 21/88 J 2107-2J

Claims (2)

[Claims] 1. An image input control circuit for inputting an image signal of an image sensor for picking up an image of a moving work and sequentially outputting it for each line in the work moving direction, and inputting image data output by this image input control circuit. An image processing device for a mobile work, comprising: an image memory for storing image data for one screen; and an image processing circuit for receiving an access permission signal from the image memory and then reading the image data in the image memory to perform image processing. Image detection is performed by extracting image data of a specific one or a plurality of lines from the image data output by the image input control circuit, and detecting the rear end of the workpiece from the change point of the level value of the extracted line image data. A work detection circuit for sending a signal to the image memory is provided, and the image memory stores image data when the work detection signal is received. An image processing apparatus for a mobile work, characterized in that the operation is stopped, the access permission signal is sent to the image processing circuit, and the storage operation of the image data is restarted by an access end signal of the image processing circuit. 2. The image processing apparatus for a moving work according to claim 1, wherein the work detection circuit generates a work detection signal when a level change is detected after a lapse of a predetermined time from the first level change point.