JP3661375B2 - Image processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image processing apparatus that captures an object with a two-dimensional imaging apparatus and processes the captured image. More specifically, the object that arrives at high speed is imaged from multiple directions with a plurality of random shutter cameras. The present invention relates to an image processing apparatus that performs A / D conversion on a plurality of captured still images and processes them as multilevel grayscale images.
[0002]
[Prior art]
In the manufacturing process and inspection process of the manufacturing industry, a plurality of two-dimensional imaging devices such as a camera using an imaging tube or a CCD imaging device are used to input a plurality of images of an object such as a workpiece flowing through the above-described process, 2. Description of the Related Art An image processing apparatus for detecting whether or not a target has a defect based on an obtained image and performing quality determination or the like is known.
[0003]
As an example of such an image processing device, it is possible to capture an image at a high speed with random shutter timing as a two-dimensional imaging device in order to image an object such as the same workpiece moving at high speed from multiple directions. A plurality of random shutter cameras are connected to the process, and the output images from the random shutter cameras are serially switched while shifting the timing, and the plurality of output images from the random shutter cameras are sequentially input. An image processing apparatus to which images taken by a plurality of random shutter cameras are input is known.
[0004]
As an example of another image processing apparatus, a camera having no shutter is connected to the process as a two-dimensional imaging apparatus, and a strobe illumination prepared for each camera is turned on at the same timing, and an image obtained by simultaneously imaging an object is imaged. 2. Description of the Related Art Image processing apparatuses that perform image processing by inputting into a memory are known.
[0005]
[Problems to be solved by the invention]
However, in the above-described conventional image processing apparatus using an image input method from a plurality of random shutter cameras, it is necessary to switch the camera serially and input an image from the camera. A camera must be installed, and the process must be lengthened accordingly.
[0006]
Further, when a plurality of cameras are simply installed in one place on the process and an attempt is made to capture images from multiple directions, the following problem occurs.
When the arrival of an object is detected, an image is read out in synchronization with a vertical scanning synchronization signal immediately after receiving the arrival detection signal (hereinafter referred to as an arrival detection signal), but a random shutter camera uses an arrival detection signal (or shutter). The vertical scanning synchronization signal is received in close proximity to the vertical scanning synchronization signal because the image is output in synchronization with the vertical scanning synchronization signal depending on whether the trigger signal) comes before the leading edge of the vertical scanning synchronization signal. In this case, there is a possibility that a plurality of random shutter cameras may not output images in synchronization with the same vertical scanning synchronization signal due to individual differences of the random shutter cameras, and the images of the plurality of random shutter cameras are input to the image processing device at the same time. May not be possible.
[0007]
An example in that case will be described with reference to the timing chart of FIG.
FIG. 4A shows a vertical scanning synchronization signal of the random shutter camera, and vertical scanning is performed in the random shutter camera every time the vertical scanning synchronization signal 20 is input. In FIG. 5A, one cycle of the vertical scanning synchronization signal 20 is indicated by V, and one vertical scan is performed in the random shutter camera in this one cycle.
[0008]
FIG. 4B is a timing sensor output 21 that is a detection signal output when an object that arrives in a process or the like is detected, and is originally generated at an arbitrary timing, but the problem to be solved by the invention is this Since it relates to the timing at which the output is generated, for the sake of explanation, the case where the detection signal comes at the same time as or immediately before the front end of the vertical scanning synchronization signal 20 of (a) is shown.
[0009]
FIG. 4C shows a trigger signal 23 for releasing the shutter of the random shutter camera generated in synchronization with the timing sensor output 21 (detection signal) of FIG. Is sent to each random shutter camera and received by each random shutter camera, the image taken from each random shutter camera in synchronization with the first vertical synchronizing signal 20 in FIG. Is output (image output).
[0010]
FIG. 4G shows an image output 27- from the first random shutter camera 1-1 in which the shutter trigger signal 23 in (c) is received before the front end of the first vertical scanning synchronization signal 20-1. 1 and since the first random shutter camera 1-1 has received the shutter trigger signal 23 before the first vertical scanning synchronization signal 20-1, the first vertical immediately after the output of the shutter trigger signal 23 An image output 27-1 is performed from the random shutter camera 1-1 in synchronization with the scanning synchronization signal 20-1.
[0011]
FIG. 4 (h) shows that the shutter trigger signal 23 shown in FIG. 4 (c) is different from that shown in FIG. 4 (g) due to the individual difference of the second random shutter camera 1-2. It is the image output 27-2 from the random shutter camera 1-2 received after the front end of the signal 20-1. In this case, the shutter trigger signal 23 is received by the second random shutter camera 1-2 after the front end of the first vertical scanning synchronization signal 20-1 shown in FIG. An image output 27-2 is performed from the random shutter camera 1-2 in synchronization with the second vertical scanning synchronization signal 20-2 which is a synchronization signal.
[0012]
As shown in FIG. 4, when the shutter trigger signal 23 is generated almost simultaneously with the front end of the vertical scanning synchronization signal 20, the reception timing of the shutter trigger signal 23 differs depending on the individual difference of each random shutter camera. As a result, the timing at which an image is output in each random shutter camera is divided into one that is synchronized with the first vertical scanning synchronization signal 20-1 and one that is synchronized with the second vertical scanning synchronization signal 20-2. The image output from the shutter camera cannot be captured simultaneously.
[0013]
In addition, in the case of a camera without a shutter, although it can be captured simultaneously, expensive stroboscopic illumination is required, and since it is easily affected by disturbance light, the surroundings of the camera must be shielded, so the device is Larger and higher cost.
[0014]
Therefore, in the present invention, a plurality of random shutter cameras are installed without increasing the process length of the process, and a plurality of random shutter cameras are provided no matter what timing the inspection object (workpiece) that arrives at high speed in the process arrives. It is an object of the present invention to provide an image processing apparatus that can simultaneously input and process image outputs from a computer.
[0015]
[Means for Solving the Problems]
The present invention includes shutter means that can be cut in synchronization with an external shutter trigger signal, picks up an object as a still image, performs raster scanning that starts with a vertical scanning synchronization signal of a fixed period, and outputs it as a video signal. Install multiple random shutter cameras to output the target object that has arrived at the predetermined position so that the target object can be imaged from multiple directions, and detect the arrival of the object moving at high speed to the predetermined position and output a detection signal Means, a shutter trigger generating means for generating a shutter trigger signal for simultaneously turning off the shutter means of all random shutter cameras by input of a detection signal from the arrival detection means, and an analog video signal output from a plurality of random shutter cameras Multiple random shutters that convert signals into digital signals and output them as multi-value grayscale image signals A plurality of A / D conversion means individually connected to the camera, an arithmetic processing means for image processing based on the multi-value grayscale image signal, and a plurality of A / D conversions individually connected to each of the plurality of random shutter cameras Of the plurality of random shutter cameras other than the first random shutter camera, the remaining random numbers other than the first random shutter camera are connected to all the second and subsequent remaining A / D conversion means except for the first A / D conversion means. The image memory that stores the multi-value grayscale image signal from the shutter camera and the vertical scanning synchronization signal of a plurality of random shutter cameras are all synchronized, and the detection signal is output from the shutter trigger generating means to all the random shutter cameras at the same timing. The first multi-value from the first A / D conversion means is generated in synchronization with the first vertical scanning synchronization signal after the shutter trigger signal is generated. The light image signal is input to the arithmetic processing means, and the second and subsequent multi-value gray image signals from the second and subsequent remaining A / D conversion means are temporarily stored in the image memory, and the first A / D conversion means is stored. The second and subsequent multi-value gray image signals are read from the image memory in synchronization with the first vertical scanning synchronization signal after the completion of the processing in the first multi-value gray image signal processing unit from And a control means for sequentially inputting the shutter trigger generation means after receiving the front end of the vertical scanning synchronization signal when the time interval between the detection signal output of the arrival detection means and the vertical scanning synchronization signal output is within a predetermined period. A shutter trigger signal is generated from the image signal, and a video signal is simultaneously output from all random shutter cameras to the corresponding A / D conversion means in synchronization with the next vertical scanning synchronization signal. Features.
[0016]
With the above configuration, video signals can be simultaneously output from all random shutter cameras, and images taken by each random shutter camera can be sequentially processed by one arithmetic processing unit.
[0017]
Further, the control unit prohibits the generation of the shutter trigger signal during a predetermined period before and after the front end of the vertical scanning synchronization signal when the time interval between the detection signal output of the arrival detection unit and the vertical scanning synchronization signal is within the predetermined period. Forbidden band generating means for outputting a band signal to the shutter trigger generating means, and the shutter trigger means generates a shutter trigger signal after the end of the forbidden band signal.
[0018]
In addition, the predetermined period is a period sufficient to cover a deviation of the reception time of the shutter trigger signal due to an individual difference of each random shutter camera.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention.
[0020]
A plurality of random shutter cameras 1 are installed on the production process, inspection process, etc. of the manufacturing industry, and a plurality of random shutter cameras 1 are installed so that an object at one imaging position in each apparatus can be imaged from multiple directions. The state of the target object is captured as a still image by a shutter that is cut in synchronization with an external shutter trigger signal, and the still image is raster-scanned by inputting a vertical scanning synchronization signal at a fixed period and output as a video signal To do. Random shutter cameras 1-1, 1-2... Indicate each of the plurality of random shutter cameras.
[0021]
The A / D converters 2 (2-1, 2-2,...) Are provided corresponding to the individual random shutter cameras 1 and convert analog video signals input from the corresponding random shutter cameras 1 into A / D. It is an A / D converter that performs D conversion and converts it into a digital multi-value grayscale image signal.
[0022]
For example, the image memory 3 is configured so that, during the image processing of the multilevel grayscale image signal from one random shutter camera 1-1 in the arithmetic processing unit 4 to be described later, another random shutter camera 1-2,. It is a memory for storing a multi-value agricultural light image signal input through the D conversion unit 2-2,.
[0023]
The arithmetic processing unit 4 inputs the multi-value grayscale image signal input from the random shutter camera 1-1 via the A / D conversion unit 2-1 directly or the multi-value grayscale image signal stored in the image memory 3. Then, image processing such as binarized area calculation is performed.
[0024]
The image memory control unit 5 controls storage and reading of the multi-value grayscale image signal with respect to the image memory 3 in accordance with an instruction from the CPU 7 to be described later.
The image memory address generation unit 6 generates a storage address in the image memory 3 of the multi-value grayscale image signal input from the A / D conversion unit 2-2,.
[0025]
The CPU 7 receives an interrupt signal from an interrupt control unit 8 (to be described later) via the bus BUS, and controls the image memory 3, the arithmetic processing unit 4, the memory control unit 5, and a shutter trigger generation unit 10 to be described later, and a random shutter camera A process for starting processing of the arithmetic processing unit 4 and the like in synchronization with the vertical scanning synchronization signal 1 and executing a program stored in a ROM or the like (not shown) to perform processing such as pass / fail judgment of an inspection object (work) A processor (MPU).
[0026]
The timing sensor 9 detects a timing at which the workpiece has arrived at an imaging position common to all the random shutter cameras 1, and outputs a signal indicating the detection to the interrupt control unit 8 described later as a timing sensor output 21. It consists of an optical detection element or the like.
[0027]
The interrupt control unit 8 inputs the timing sensor output 21 from the timing sensor 9 and interrupts the CPU 7 when the timing sensor output 21 is input.
The shutter trigger generator 10 receives a control from the CPU 7 when a workpiece arrives, and generates a shutter trigger signal 23 for each of the random shutter cameras 1-1, 1-2,.
[0028]
The forbidden band generation circuit 11 generates a forbidden band signal 28 for prohibiting the generation of the shutter trigger signal 23 with a certain width immediately before the vertical scanning synchronization signal of the random shutter camera 1, and the shutter trigger signal generated by the shutter trigger generation unit 10. 23 is delayed until the end of the forbidden band signal 28 to prevent the output timing of the video signal of the still image from each random shutter camera 1 from varying due to the individual difference of each random shutter camera 1.
[0029]
The forbidden band signal 28 has a predetermined time width with respect to the predicted time when the next vertical scanning synchronization signal rises in a predetermined period when an external vertical scanning synchronization signal of a predetermined period is input to the forbidden band generation circuit 11. For example, when a vertical scanning synchronization signal is input to the forbidden band generation circuit 11, a variation in timing of video output of the random shutter camera is predicted from a time when a next vertical scanning synchronization signal is predicted to be input by a timer or the like. The forbidden band signal 28 is started to be input to the shutter trigger generation unit 10 at a time earlier by the minute, and the forbidden band signal 28 is maintained by the timer or the like until the time after the predicted vertical scanning synchronization signal time. In the case where the instruction to generate the shutter trigger signal 23 is received from the CPU 7 during the sustain period of the forbidden band signal 28. Delays the generation of only the shutter trigger signal 23 between the forbidden band signals 28.
[0030]
With the above configuration, even when the timing sensor output 21 is output from the timing sensor 9 at the same timing or slightly before the front end of the vertical scanning synchronization signal of the random shutter cameras 1-1, 1-2,. To realize an image processing apparatus that can simultaneously input images from the shutter cameras 1-1, 1-2,..., And can input images from the random shutter cameras 1-1, 1-2,. Can do.
[0031]
In the present embodiment, the forbidden band generation circuit 11 is configured to directly output the forbidden band signal 28 to the shutter trigger generation unit 10. For example, the forbidden band generation circuit 11 outputs the forbidden band signal 28 to the CPU 7. Until the CPU 7 finishes outputting the forbidden band signal 28 and delays sending an instruction to output the shutter trigger signal 23 to the shutter trigger generating unit 10. You may comprise so that the instruction | indication may be sent after completion | finish of an output.
[0032]
FIG. 2 is a timing chart showing the operation of the main part of the image processing apparatus having the configuration shown in FIG. FIG. 3 is a timing chart showing an operation when the work arrives, that is, when the generation of the timing sensor output 21 approaches the front end of the camera vertical scanning synchronization signal 20 in the timing chart of FIG.
[0033]
2 and 3, the vertical scanning synchronization signal 20 shown in FIG. 2A is a vertical scanning synchronization signal common to the plurality of random shutter cameras 1-1, 1-2,. The signal is indicated by 20-1, and the second vertical scanning synchronization signal is indicated by 20-2. That is, the i-th vertical scanning synchronization signal is represented by 20-i (i = 1, 2, 3,...). One period of the vertical scanning synchronization signal 20 (that is, one vertical scanning period in the random shutter camera 1) is denoted by V.
[0034]
The timing sensor output 21 shown in FIGS. 2B and 3B is a workpiece detection signal output from the timing sensor 9 when a workpiece arrives. In FIG. 2B, the timing sensor output generated when the first workpiece arrives is denoted by 21-1, and the timing sensor output generated when the second workpiece arrives is denoted by 21-2. Show.
[0035]
The shutter trigger signal 23 shown in FIGS. 2C and 3C is a signal generated from the shutter trigger generation unit 10 via the interrupt control unit 8 and the CPU 7 by the timing sensor output 21, and is a random shutter. This is a signal for releasing the shutter of the camera 1.
[0036]
The processing of the arithmetic processing unit shown in FIG. 2D is performed in the processing period of the camera image input 25 from the A / D conversion unit 2-1 and the image memory image reading 26 from the image memory 3 in the arithmetic processing unit 4. Etc. The camera image input 25 is a direct input from the first random shutter camera 1-1 to the arithmetic processing unit 4 of the multi-value grayscale image signal via the A / D conversion unit 2-1. The image memory image read-out 26 is, for example, the arithmetic processing unit 4 for the multi-value grayscale image signal temporarily stored in the image memory 3-1 from the second random shutter camera 1-2 via the A / D conversion unit 2-2. When the third and subsequent random shutter cameras 1 exist, the input of the multi-value grayscale image signal input from the corresponding image memory 3 to the arithmetic processing unit 4 is also shown. ing. FIG. 2D shows a processing period of the arithmetic processing unit 4 including a hatched portion indicating the camera image input 25 and the image memory image reading 26 and a non-hatched portion indicating a calculation processing period of the image signal input thereby. P1 and P2 are shown.
[0037]
The image memory input shown in FIG. 2 (e) is a multi-value grayscale that is temporarily stored in the image memory 3 from the second random shutter camera 1-2 or later and then output to the arithmetic processing unit 4 as the image memory image readout 26. The input timing of the image signal to the image memory 3 is shown. The image memory input 24 indicates, for example, an input period of a multi-value grayscale image signal input from the random shutter camera 1-2 to the image memory 3-1 via the A / D conversion unit 2-2. Further, FIG. 2E shows the input of the multi-value grayscale image signal from the second random shutter camera 1-2, but this also corresponds to the case where the third and subsequent random shutter cameras 1 exist. The multi-value grayscale image signal output from the random shutter camera 1 via the A / D converter 2 is also input to the image memory 3 at exactly the same timing as in FIG.
[0038]
The forbidden band signal 28 shown in FIG. 3 (f) has a constant width from the forbidden band generating circuit 11 to the shutter trigger generating unit 10 immediately before the front end of the vertical scanning synchronization signal 20 synchronized with all the random shutter cameras 1. Generated. The forbidden band signal 28 delays the generation of the shutter trigger signal 23 of the random shutter camera 1 by the shutter trigger generation unit 10 until the end of the generation period, and the random shutter camera 1 due to individual differences of the random shutter cameras 1. Is a signal having a time width t1 for prohibiting the generation of the shutter trigger signal 23 from the shutter trigger generation unit 10 in order to prevent the output timing of the video signal of the still image from being varied.
[0039]
An image output 27-1 of the camera 1-1 shown in FIG. 3G indicates an output period of a video signal of a still image from the first random shutter camera 1-1. The image output 27-1 from the first random shutter camera 1-1 is output in synchronization with the vertical scanning synchronization signal 20-2 in FIG. In this case, the first random shutter camera 1-1 receives the shutter trigger signal 23 immediately before the reception of the front end of the vertical scanning synchronization signal 20.
[0040]
An image output 27-2 of the camera 1-2 shown in FIG. 3 (h) indicates an output period of a video signal of a still image from the second random shutter camera 1-2. The image output 27-2 from the second random shutter camera 1-2 is output in synchronization with the vertical scanning synchronization signal 20-2 in FIG. In this case, the second random shutter camera 1-2 receives the shutter trigger signal 23 immediately after receiving the front end of the vertical scanning synchronization signal. Even when the third and subsequent random shutter cameras 1 exist, the output timing of the video signals of those still images is the same as that of the random shutter cameras 1-1 and 1-2 described above. Even when the random shutter camera 1 exists, a video signal of a still image is output from all the random shutter cameras 1 at the same timing.
[0041]
Here, the relationship between the timings (a), (b), (c), (d), and (e) in FIG. 2 will be described.
The camera vertical scanning synchronization signal 20 in FIG. 2A is a synchronization signal generated at a constant cycle at a timing common to all the random shutter cameras 1.
[0042]
The timing sensor output 21 in FIG. 2 (b) is a signal generated when a workpiece comes in the inspection process. Therefore, if the process speed of the process and the interval between the workpieces are constant, the timing sensor output 21 is output at a constant interval. There is no correlation between the timing of the generation of the camera vertical scanning signal 20 shown in FIG. 2A and the output timing of the camera vertical scanning synchronization signal 20 shown in FIG. Output at timing.
[0043]
Since the shutter trigger signal 23 in FIG. 2C is a signal generated in synchronization with the front end of the output of the timing sensor output 21 in FIG. 2B, the camera vertical scanning synchronization signal 20 in FIG. Therefore, as with FIG. 2B, the output timing of the camera vertical scanning synchronization signal 20 in FIG. 2A is output at an arbitrary timing.
[0044]
The camera image input 25 in FIG. 2D is the same as the camera vertical scanning synchronization signal 20 in FIG. 2A after the shutter trigger signal 23 in FIG. 2C is received by the first random shutter camera 1-1. -2 is a multi-value grayscale image signal of a still image captured by the random shutter camera 1-1 that is input to the arithmetic processing unit 4 in synchronization with the front end of -2, and the camera image input 25 The multi-value grayscale image of the still image captured by the random shutter camera 1-2 that is input to the arithmetic processing unit 4 in synchronization with the front end of the camera vertical scanning synchronization signal 20-5 in FIG. Signal.
[0045]
The image memory input 24 in FIG. 2E is a multi-value grayscale image signal of a still image captured by the random shutter camera 1-2 that is input to the image memory 3 simultaneously with the camera image input 25 in FIG. is there.
[0046]
Accordingly, the camera image input 25, the image memory image read-out 26, and the image memory input 24 are generated at a timing synchronized with the front end of the camera vertical scanning synchronization signal 20 in FIG. 2A, but the timing sensor output 21 and the shutter trigger signal are generated. 23 is generated at an arbitrary timing with no correlation with the timing of the front end of the camera vertical scanning synchronization signal 20 in FIG.
[0047]
Next, the relationship between the timings (a), (b), (f), (c), (g), and (h) in FIG. 3 will be described.
The signal generation timing for FIG. 3A, FIG. 3B, and FIG. 3C is generally as described in FIG. 2, but in FIG. 3, the timing sensor output of FIG. 21 is generated close to the vertical scanning synchronization signal 20 in FIG. This timing is the same as in the case of FIG. 4 of the prior art. In FIG. 4 of the prior art, the image output 27-1 of the first random shutter camera 1-1 in FIG. 4G and the image output 27-2 of the second random shutter camera 1-2 in FIG. 4 starts due to the variation in the reception timing of the shutter trigger signal 23 with respect to the reception of the front end of the vertical scanning synchronization signal 20 due to the individual difference, for one cycle of the camera vertical scanning synchronization signal 20 in FIG. It is only shifted. In FIG. 3, the forbidden band 28 in FIG. 3F is changed from the forbidden band generating circuit 11 to the shutter. Since it is generated for the trigger generation unit 10, even when the timing sensor output 21 is generated at the same timing as in FIG. 4, the shutter trigger generation unit 10 generates the shutter trigger signal 23 in the generation period of the forbidden band 28 in FIG. Since the shutter trigger signal 23 is generated by being delayed by an amount, the random shutter camera 1 does not receive the shutter trigger signal 23 prior to the front end of the camera vertical scanning synchronization signal 20-1 in FIG. Both the image output 27-1 of the first random shutter camera 1-1 and the image output 27-2 of the second random shutter camera 1-2 in FIG. 3H are the same as in FIG. It is started at the same timing in synchronism with the front end of the second camera vertical scanning synchronizing signal 20-2.
[0048]
Next, the operation of FIG. 1 will be described with reference to FIG. As can be understood from FIGS. 2A, 2D and 2E, the camera image input 25 output from the random shutter camera 1 and A / D converted by the A / D converter 2 A multi-value grayscale image signal such as the image memory input 24 (exactly, a video signal of a still image captured by the random shutter camera 1) is always output in synchronization with the camera vertical scanning synchronization signal 20 in FIG. It will be.
[0049]
As described above, the period during which one screen is scanned by one random shutter camera 1 corresponds to the cycle V of the camera vertical scanning synchronization signal 20, and the scanning method for the random shutter camera 1 is interlaced ( Depending on whether it is interlaced scanning) or non-interlaced (non-interlaced scanning), two cycles (2V period, 2 field periods) of one cycle of the camera vertical scanning synchronization signal 20 are output as one screen. One cycle (1 V period, 1 field period) is scanned and output as one screen.
[0050]
FIG. 2 corresponds to a 1V period in which the image output period of the random shutter camera 1 is one cycle of the camera vertical scanning synchronization signal 20, that is, the case where the scanning method of the random shutter camera 1 is non-interlaced.
[0051]
The workpiece that is the object in the inspection process arrives within the detection range of the timing sensor 9, and the timing sensor output 21 is generated from the timing sensor 9, and the interrupt signal generated by the interrupt control unit 8 is generated by the timing sensor output 21. When input to the CPU 7, a command (control signal) is output from the CPU 7 to the shutter trigger generation unit 10, the arithmetic processing unit 4, the image memory 3, the image memory control unit 5, and the like.
[0052]
In response to a command from the CPU 7, a shutter trigger signal 23 in FIG. 2C is output from the shutter trigger generator 10, output from each random shutter camera 1, A / D converted by the A / D converter 2, and output. The camera image input 25 and the image memory input 24 are processed when the camera image input 25 of the first random shutter camera 1-1 is input to the arithmetic processing group 4 at the timing shown in FIG. At the same time, as shown in FIG. 2 (e), the still image output from the random shutter camera such as the second random shutter camera 1-2, or the random shutter camera 1-3 when there are more cameras than the second random shutter camera 1-2. The video signal of the image is input and stored in the image memories 3-1, 3-2, etc. as the image memory input 24 via the A / D converters 2-2, 2-3.
[0053]
In synchronization with the camera vertical scanning synchronization signal 20-5 of FIG. 2A after the completion of the arithmetic processing in the arithmetic processing unit 4 of the camera image input 25 of the first random shutter camera 1-1, FIG. The image memory input 24 of the random shutter camera 1-2 (multi-value grayscale image signal of the random shutter camera 1-2 stored in the image memory 3-1 at the same timing as the camera image input 25 of the random shutter camera 1-1). Then, it is transferred to the arithmetic processing unit 4 as the image memory image reading 26, and the arithmetic processing unit 4 performs arithmetic processing on the multi-value grayscale image signal. Similarly, in the image memory 3-2,..., When the processing of the multilevel grayscale image signal stored in the previous image memory 3 in the arithmetic processing unit 4 is completed, the camera vertical scanning in FIG. In synchronization with the synchronization signal 20, it is read and processed sequentially.
[0054]
FIG. 3 is a timing chart showing the operation of this embodiment when the timing sensor output 21 due to the arrival of the workpiece in the inspection process approaches the first vertical scanning synchronization signal 20-1 of the random shutter camera 1 as described above. is there. When the front end of the timing sensor output 21 comes at the same time as or immediately before the front end of the vertical scanning synchronization signal 20-1, the shutter trigger signal 23 sets the front end of the vertical scanning synchronization signal 20-1 in FIG. 3B, the output is output after the end of the forbidden band signal 28 as shown in FIG. 3C, that is, the front end of the vertical scanning synchronization signal 20-1. As a result, the image outputs 27-1, 27-2,... From the random shutter cameras 1-1, 1-2,... Are all synchronized with the second vertical scanning synchronization signal 20-2. Are simultaneously input to the A / D converter 2.
[0055]
The width t1 of the forbidden band signal 28 in this case absorbs that the reception of the shutter trigger signal 23 in each random shutter camera 1 varies before and after the front end of the camera vertical scanning synchronization signal 20 due to individual differences among the random shutter cameras 1. It is set to a value sufficient to
[0056]
With the above configuration, even when the generation of the timing sensor output 21 indicating the arrival detection of the workpiece at the imaging position of each random shutter camera 1 in the process approaches the front end of the camera vertical scanning synchronization signal 20, a plurality of random From the shutter cameras 1-1, 1-2,..., The video signal of the still image of the workpiece is input to the A / D converters 2-1, 2-2,. , The multi-value grayscale image signals of the video signals output from the A / D conversion units 2-1, 2-2,... Are read by the arithmetic processing unit 4 and the image memories 3-1,. The unit 4 can sequentially calculate the multi-value grayscale image signal of the video signal of each random shutter camera 1.
[0057]
In the case of the interlaced (interlaced scanning) random shutter camera 1, the camera image input 25 or the image memory input 24 is only increased to two fields, and other timings are the same as those described above.
[0058]
【The invention's effect】
According to the present invention, the process length of the same object is extended at the same position in the process, regardless of the timing of the arrival of the object that arrives at high speed with respect to the vertical scanning synchronization signal of the random shutter camera. In addition, it is possible to simultaneously capture images from a plurality of directions with a plurality of random shutter cameras, and sequentially process the captured plurality of camera images with one arithmetic processing unit.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a system configuration of a graphic processing apparatus according to an embodiment of the present invention.
FIG. 2 is a timing chart showing the operation of the main part of the embodiment.
FIG. 3 is a timing chart showing an operation when the workpiece arrival detection and the vertical scanning synchronization signal generation timing in the random shutter camera approach in the embodiment.
FIG. 4 is a timing chart showing an operation when a workpiece arrival detection and a generation timing of a vertical scanning synchronization signal in a random shutter camera approach in a conventional graphic processing apparatus.
[Explanation of symbols]
1 (1-1, 1-2,...) Random shutter camera
2 (2-1, 2-2, ...) A / D converter
3 (3-1, ...) Image memory
4 Arithmetic processing part
5 Image memory controller
6 Image memory address generator
7 CPU
8 Interrupt control unit
9 Timing sensor
10 Shutter trigger generator
11 Forbidden band generation circuit

Claims (4)

Random shutter that has shutter means that can be cut in synchronization with an external shutter trigger signal, picks up an object as a still image, performs raster scanning starting with a vertical scanning synchronization signal of a fixed period, and outputs it as a video signal A plurality of cameras are installed so that an object that has arrived at a predetermined position can be imaged from multiple directions,
Arrival detection means for detecting the arrival of the object at the predetermined position and outputting a detection signal;
Shutter trigger generating means for generating a shutter trigger signal for simultaneously turning off the shutter means of the all-random shutter camera by the detection signal input from the arrival detection means;
Video signals output from the plurality of random shutter cameras are converted from analog signals to digital signals and output as multi-value grayscale image signals, and a plurality of A / Ds individually connected to the plurality of random shutter cameras. Conversion means;
Arithmetic processing means for performing image processing based on the multi-value grayscale image signal;
Of the plurality of A / D conversion means individually connected to each of the plurality of random shutter cameras, all of the remaining A / D conversion means after the second except for the first A / D conversion means are connected. An image memory for storing the multi-value grayscale image signal from the remaining random shutter cameras other than the first random shutter camera among the plurality of random shutter cameras;
Synchronize all vertical scanning synchronization signals of the plurality of random shutter cameras, and generate a shutter trigger signal from the shutter trigger generation means to the all random shutter cameras at the same timing by outputting the detection signal, and generate the shutter trigger signal The first multi-value grayscale image signal from the first A / D conversion means is input to the arithmetic processing means in synchronization with the first subsequent vertical scanning synchronization signal, and all the remaining A and the subsequent A are supplied. The second and subsequent multilevel grayscale image signals from the / D conversion means are temporarily stored in the image memory, and the first multilevel grayscale image signal from the first A / D conversion means is processed in the calculation processing means. In synchronism with the first vertical scanning synchronization signal after the end of, the second and subsequent multi-value grayscale image signals are read from the image memory and sequentially supplied to the arithmetic processing means. A control means for the force,
When the time interval between the detection signal output of the arrival detection means and the vertical scanning synchronization signal output is within a predetermined period, the control means receives a shutter trigger from the shutter trigger generation means after receiving the front end of the vertical scanning synchronization signal. An image processing apparatus for generating a signal and outputting a video signal simultaneously from all the random shutter cameras to the corresponding A / D conversion means in synchronization with the next vertical scanning synchronization signal. The control means generates the shutter trigger signal in a predetermined period before and after the front end of the vertical scanning synchronization signal when the time interval between the detection signal output of the arrival detection means and the vertical scanning synchronization signal is within a predetermined period. Forbidden band generating means for outputting a forbidden band signal to the shutter trigger generating means;
The image processing apparatus according to claim 1, wherein the shutter trigger unit generates a shutter trigger signal after the forbidden band signal ends. The image processing apparatus according to claim 1, wherein the predetermined period is a period sufficient to cover a deviation of a reception time of a shutter trigger signal due to an individual difference of each random shutter camera. In an image processing apparatus that captures and processes each image obtained by capturing an object moving along a predetermined movement path from multiple directions with a plurality of random shutter cameras,
Arrival detection means for detecting that the object has arrived at a predetermined imaging position in the movement path and outputting a detection signal;
When there is an output of the detection signal, a shutter trigger generating means for outputting a shutter trigger signal to all of the plurality of random shutter cameras in synchronization with a vertical scanning synchronization signal common to the plurality of random shutter cameras;
A period sufficient to cover the deviation of the reception time of the shutter trigger signal due to individual differences of the plurality of random shutter cameras is set as a prohibited band with respect to the vertical scanning synchronization signal, and the Forbidden band generating means for prohibiting the output of the shutter trigger signal by the shutter trigger generating means when a detection signal is output, and outputting the shutter trigger signal after the forbidden band ends;
An image processing apparatus comprising:

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