JPS5941990A - Processing circuit of picture signal - Google Patents

Abstract

PURPOSE:To inspect exactly the vicinity of a joint, by scanning two-dimensionally the surface of an object to be inspected, binary-coding with high sensitivity only a mask area, also detecting a variation point of a binary-coded level on a horizontal scanning line, and extract-processing only a small specified area. CONSTITUTION:A medicine capsule 12 of an object to be inspected consists of a body 12a and a cap 12b, and they are locked to each other by a fitting hole 12c. A video signal of a TV camera which scans the capsule 12 is supplied to a low sensitivity binary-coding circuit 22 and a high sensitivity binary-coding circuit 23 through an amplifier 21. By an output of the circuit 22, the whole image is stored in a binary-coding picture memory 25. A high sensitivity moving mask generating circuit 24 is connected to the circuit 23, and a signal of a range M is stored in a binary-coding picture memory 28. A counting value of a joint counter 33 is inputted to a mask correction controlling circuit 29 and a reference position S is calculated. Also, width DELTAl is set by a correction use mask width setting circuit 30, and a binary-coded picture between the width DELTAl is reconstituted and is stored in a picture memory 31. Therefore, the vicinity of a joint can be inspected exactly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an image suitable for use in detecting flaws, etc. on the surface of an object to be inspected by image signals obtained by two-dimensionally scanning the surface of the object to be inspected in the horizontal and vertical directions using an imaging device. The present invention relates to a signal processing circuit, and more particularly to an image signal processing circuit particularly suitable for use in detecting flaws at the seam between a body and a cap of a capsule consisting of a body and a cap.

Generally, when inspecting the appearance of key agent capsules, etc., 1.
It is important to check for yj, etc.

Gap and body #! This is because corn grains are prone to hangnails, and if the cap or body is scratched, the storage agent filled inside may leak out, which is inconvenient.

Figure 1 shows this kind of capsule outside 1. ;17 is a front view of the inspection device. In the figure, 1 is the main body of the capping shed, 2 is the hopper that carries the capsules, 3 is the feed drum, 4 is the first inspection drum, 5 is the second inspection drum, and 6 is the defective drum. 7 is a good product chute, 8 is a sensor (there are 2 of them), 9 is a scraping brush, 1o is a mirror (there are 2 of them). ) are transferred to a pocket provided around the supply drum 3.At this time, capsules that do not fit into the pocket are returned to the hopper 2 by the return brush 9.Capsules transported by the rotating supply drum 3 Next, in a pocket provided around the first inspection drum 4,
It is transferred in the same way as in the supply drum 3. 1st
FIG. A is a top view showing a state in which the capsules 12 are accommodated in the leg pockets 11 provided around the supply #c1 inspection drum 40. At this time, since a negative pressure is applied to the pocket 11 from the inside by means not shown, the capsule 12 is attracted to the pocket 11, and even if the drum 4 rotates, the capsule 12 will not fall.

Returning to FIG. 1, while the capsule is conveyed by a distance corresponding to half the rotation of the first inspection drum 4, light is projected by means not shown, and the reflected light is sent to the sensor 8 via the mirror 10. The appearance of the lower half is inspected. The capsule is then transferred to a pocket on the periphery of the second inspection drum 5, and the visual inspection of its upper half is then carried out in the same way. As a result of the inspection, if the products are good, they are sorted to the non-defective chute 7, and if they are defective, they are sorted to the defective chute 6.

FIG. 2 is an explanatory diagram of the appearance inspection status of the capsule. The capsule 12 consists of a body 12a and a cap 12b. Furthermore, the body 12a and the cap 121) are locked to each other by the tcq mating hole 12C. 2nd AFp is a side view of the capsule in the 2nd va, seen after being rotated 90 degrees, and it can be seen that the body 12a and the cap 12b are mutually locked by the fitting hole 12C.

Returning to FIG. 2, the capsule 12 is exposed to the current light q1, and the industrial television camera 13 is inspecting the appearance of the capsule as a sensor.

Now, the problems of the prior art regarding the inspection of the nth joint between the cap and the body of a capsule will be explained below.

Generally, when inspecting the appearance of a capsule, the presence or absence of scratches is inspected by examining the binary output of the TF7i image signal obtained by scanning the capsule surface with a television camera as a sensor. In some areas, the image signal obtained from the television camera becomes weak due to shadows caused by the overlapping of the cap and body. For this reason, it is necessary to increase the amount of irradiation light by firing a strobe or the like only in the area near the seam, to raise the level of the obtained image signal, and to perform binarization with high sensitivity. This necessity necessitates a masking means to distinguish the area near the seam of the capsule from the rest.

In order to wear a mask correctly in places, the position of the capsule must remain constant at all times. However, in the external appearance inspection of the capsule, as described above with reference to FIGS. 1 and 1A, the capsule 12 is inspected while being conveyed while being accommodated in the pocket 11 of the drum. Therefore, it is necessary to store the capsule in a pocket,
At that time, the item may be accommodated with a slight positional shift within the pocket. For this reason, the capsules are not always at a constant position with respect to the television camera, and each capsule may be slightly misaligned, making it difficult to apply one mask correctly.

The problem caused by this will be explained next with reference to FIG.

In FIG. 3(a), if a mask A is applied near the seam M of the capsule 12 so as not to include the fitting hole 12c, as shown in FIG. Since the image of the fitting hole does not appear in the image, it is possible to correctly inspect the area before the seam is formed.

However, if the capsule 12 is misaligned and the mask is covered with the fitting hole 12C as shown in Fig. 43 (R), then the binary value is In the image created by the conversion output, an image 12c due to the fitting hole appears, and as a result of the inspection, although the capsule with the fitting hole and no other tower is a good product, it is not fitted properly. There have been cases where the image 12C' due to the matching hole is erroneously determined to be a defect and is disposed of as a defective product.

The present invention has been made in order to solve the problem in the prior art such as the "double series", and therefore, the purpose of the present invention is to solve the problems in the prior art, such as "double series". However, the fΦ of the fitting hole does not appear in the image created by the binarized output of the image signal from the television camera.
An object of the present invention is to provide a processing circuit capable of processing an image signal so that only the signal before the seam is formed appears.

The present invention will now be described in detail with reference to the drawings.

FIG. 4 is a diagram explaining the principle of the present invention.
Figure O is an external view of the capsule, and Figure 4 (B) shows the overall image of the capsule using the low-sensitivity binarized output of the image signal obtained by scanning this with a television camera. . Since low-sensitivity binary output is used, the fitting hole 12
The image due to c does not appear.

From the image in Fig. 4←), the tip position IF and the rear end position of the capsule can be determined.

Next, as shown in FIG. 4(c), a mask M is applied over a rough area that may include a fitting hole in addition to the seam area, and an image signal obtained from a television camera is applied to this area. When an image is drawn using the high-sensitivity binarized output of , it becomes as shown in Fig. 4). Since high-sensitivity binarized output is used, in addition to the seam area serving as pair 9 to be inspected, an image 12c' of the fitting hole, which is originally unnecessary, also appears.

Next, in FIG. 4), a reference position S near the starting position of the seam area is determined by law (the method for determining it will be described later). , S to Δl, J:f912c can be removed from the high-sensitivity binarized output image shown in FIG. 4 (=) in the fitting hole. If the high-sensitivity 2-gef Riki Kawa image of only the seam area obtained in this way is combined with the capsule whole obtained by the low-sensitivity binarized output shown in 4v4 (''), the result is shown in Fig. 4 (E). Like,
You can get the image.

By inspecting the image in Fig. 4 (e), it is possible to correctly inspect only the seam Pi area without being disturbed by the fitting hole. M's ff@circle is
Even if the capsule is misaligned to the maximum extent, it is sufficient that the seam area falls within that range.In extreme cases, the range may include the entire capsule, but if this is done, high-sensitivity binarization will not be possible. It is not a good idea to make In of the mask M too large because the memory capacity required to write the output data becomes large.

In addition, in FIG. 4), the range Il is a value determined depending on the type of capsule, so it can be easily specified once the reference position S of the capsule is determined.

Next, an example of a method for determining the reference position Iff, S will be explained with reference to FIG.

FIG. 5 is an enlarged view of FIG. 4). In the same figure, C1
Now, assuming that there are nine horizontal 1E lines, the 1st I from the top
■, 2nd TI, . . . 9th H and the number - J.

Horizontal scanning line melting 1H is interrupted when the binarization level falls to O at the coordinate position O, and restarts when the binarization level rises to 1 at the coordinate position R.
Similarly, the second H is interrupted at the coordinate position and resumes at the coordinate position 'C'. .

In addition, the 6th II is interrupted at the coordinate positions ■ and O, and restarts at the coordinate positions θ and ■.

Note that the point at which the binarization level stopped (the point at which the binarization level fell to O) is marked 0, and the point at which it resumed (the point at which the binarization level rose to 1)
is indicated by an X mark. The point of interest is the interrupted point marked 0, and the restart point marked X is not set to rIrJ.

Here, calculate the number of broken point 0 marks at each coordinate position "qσ)-" and calculate the crotch GJ corresponding to the position +7).
When counted by a counter (not shown), the results shown in Table 1 are obtained.

Using the number of 0 marks (3) in Table 1 as a threshold, coordinate positions where the number of 0 marks is 3 or more are found to be V, O, and Q. Among coordinate positions 0 and O, the leftmost coordinate position is ■, and the rightmost coordinate position is O. (Note that in this example) there were only two coordinate positions with a threshold value of 3 or higher, In general, it can be assumed that there are many more.) Therefore, if the average of the coordinate positions ○ and ○ is taken, the coordinate position becomes the average value, so this coordinate position is determined as the reference position S, and a range of Δl is specified from this.

The threshold value can be set arbitrarily, and the reason for setting the threshold value is to avoid iUW& due to noise.

FIG. 6 is a block diagram showing one embodiment of the present invention. In the figure, 21 is a video amplifier, 22 is a low-sensitivity binarization circuit (a circuit with a high threshold level of binarization), and 23 is a high-sensitivity binarization circuit (a circuit with a low threshold level of binarization). circuit)
', 24 is a high-sensitivity moving mask generation circuit, 25 is a binarized image memory, 26 is a left side minimum rising coordinate detector, 27 is a right side maximum falling coordinate detector, 28 is a binarized image memory, 2
9 is a mask correction control circuit, 30 is a correction mask width setting circuit, 31 is a reconstructed image memory, 32 is a microprocessor, and 33 is a seam position counter.

Next, pb creation will be explained. The video amplifier 21 is a circuit section that performs amplification, noise processing, etc. on a video signal from a television camera (not shown), and this output No. 6 is a low-sensitivity 2
It is connected to the value converting circuit 22 and the high-level two-carrying circuit 23.

The output of the low-sensitivity binarization circuit 22 is - water r111 phrase'
The rising and falling coordinates are detected, and these coordinates are stored in the binarized image memory 25 as representing the output between Issui and JJRJ (The recorded image is as shown in Figure 4). ).

In order to detect the leftmost position on the screen of the Capsule/L image (coordinate !4 (position number 4 in Figure 4), a left side minimum rising coordinate detector 26 is provided, and for each -horizontal scan, Compare the values of the coordinates of the first rising point.Similarly, the coordinates of the rightmost point (fourth
In order to detect the position at the drawing end, the right maximum falling point coordinate detector 27 is used and the values of the coordinates of the final falling point are compared. The high-sensitivity binarization circuit 23 has a range [7JI (range M in FIG. By connecting the mask signal 2, unnecessary signals other than the range M are prevented from being stored in the binarized image memory 28.

The seam position counter 33 is set at coordinate positions 0 to 0 as shown in FIG.
It consists of a plurality of counters corresponding to each of (3), and each counter counts how many horizontal scanning lines have fallen at each coordinate position, as described above.
The direction value is sent to the mask correction control circuit 29, and the above-mentioned base position Hs is calculated in this correction control circuit 9. Each counter has 1 byte (8 bits) of memory, which is fζ! If this is done, the number of horizontal scanning lines in the -vertical period rKJ is at most 256, which can be said to be sufficient as a counting capacity.

The mask correction control circuit 29 starts the correction operation at the timing immediately after capturing the image of the capsule in the vertical scanning period. The correction mask width setting circuit 30 sets the mask 4 from the correction mask start point (the reference point S described above) to the end of the mask.
This is a circuit for setting the width Δe of m4υJ2.The mask correction control circuit 29 uses the Fi expansion i-+'7 that has already been read into the memories 25 and 28 at the scanning speed on the memory, not at the scanning speed of the television camera. The information is reconstructed and output to the memory 31. In other words, the pulse (M4M Second term rtlJl
(The period e is easily determined from the calculated reference position [8 and the leftmost coordinate F). signal will be ignored.

Synchronizing with the end of the pulse representing the correction mask position, a pulse with the correction mask width (20 radial Δl in Fig. 4) is generated (
The high-sensitivity binary signal is valid during the period of this pulse. Through this series of operations, the uncorrected binary value f[5
The image R (FIG. 4 2) becomes a corrected binarized image (FIG. 4 H) and is stored in the reconstructed image memory 31. In order to minimize the processing time, the mask correction control circuit that reads and writes data to and from the memory associated with such image reconstruction is preferably performed by wired logic rather than by a microcomputer. The microprocessor 32 performs various determination operations depending on the contents of the reconstructed image memory 31.

According to this invention, the displacement of the capsule within the pocket is semi-mechanically reduced to N1. There is no need for tight constraints, and there is no need to adjust the high-sensitivity mask, yet it is possible to inspect a specific area of the inspection object with stability and high performance.

The present invention is applicable not only to the capsule appearance inspection situation described above, but also to a specific region inspection device for a sample in which the V sample to be inspected inevitably moves within a minute range.

[Brief explanation of drawings]

Figure 1 is a front view of the capsule appearance inspection device, Figure 1A is a top view showing the capsules housed in the pockets on the drum surface, Figure 2 is an explanatory diagram of the capsule appearance inspection situation, and Figure 12A is the same as in Figure 2. A side view of the capsule after it has been rotated 90 degrees, Fig. 3 is an explanatory diagram of the problem caused by misalignment of the mask applied to the capsule, Fig. 4 is an illustration of the principle of the present invention, and Fig. 5 is an illustration of the principle of the present invention. An explanatory diagram of the reference position determination method, FIG. 6 is a block diagram of the present invention. ...Hopper,
3... Supply drum, 4... First inspection drum, 5... Second inspection drum, 6...
Defective jute, 7... Good chute, 8...
...Seven fingers, 9...Kakeback brush, 10
...Mirror, 11...Pocket, 12
... Capsule, 13 ... Industrial television camera, 21 ... Video amplifier, 22 ...
...Low sensitivity binarization circuit, 23...High sensitivity binarization circuit, 24...High sensitivity moving mask generation circuit, 2
5... Binarized image memory, 26... Left side minimum rising coordinate detector, 27... Right side maximum falling FJ4t"J detector, 28...・Binarized image memory, 29...Mask correction control circuit 1, 30
...Correction mask width setting circuit, 31...
・M configuration image memory, 32... Microprocessor, 33... Seam position counter 1 Figure 1 Pile IA diagram @ Figure 2 Figure 3

Claims (1)

[Claims] l) A processing circuit for image signals obtained by two-dimensionally scanning the surface of the object to be inspected in the horizontal and vertical directions using a scanning device.It is a circuit that processes the image signals obtained by scanning the surface of the object to be inspected in two dimensions in the horizontal and vertical directions. A first 2pn conversion circuit, an hXl memory that stores the entire image of the object A by low-intensity binary output data from the first binarization circuit, and and a second binarization circuit that receives a mask signal and binarizes and outputs the pTii expanded signal at the full signal level within the range specified by the mask No. 4k1; A specific area (range R specified by the mask signal) of the entire image of the object to be inspected is stored using high-sensitivity binary data from the circuit.
2, a means for determining a reference position r4 related to a change point of the binarization level on each horizontal scanning line within the specific area of tn 1, and a means for determining a reference position r4 related to a change point of the binarization level on each horizontal scanning line within the specific area of tn 1; means for setting a range in which a small second specific area that fits within the area is located, and a reference position determined by the reference position determining means and the data stored in the first and tJ2 memories, Using the position range of the second specific area, only the second specific area in the entire image of the object to be inspected is processed using high-sensitivity binarized output data, and the remaining area is processed using low-sensitivity binarized output data. An image signal processing circuit comprising: a correction control circuit that creates and outputs correction data represented by the data;