JPH0619335B2 - Object recognition device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an object recognition device, and in particular, the presence / absence of an object and the object based on a video signal obtained by imaging an object to be recognized using a television camera. The state of the object, such as the presence or absence of defects, can be observed.

[Conventional technology]

As this type of object recognition device, a plurality of observation positions are predetermined on a screen imaged by a television camera, and a signal level of a video signal (that is, a luminance signal level) corresponding to each observation position is predetermined. It has been proposed that the presence / absence of an object or the presence / absence of a defect in each part of the object be recognized by determining whether or not it is within the range of the determination reference level.

[Problems to be solved by the invention]

The object recognition device having such a configuration converts the amount of reflected light reaching the camera from the observed object into the luminance of the video signal, and obtains the object recognition output by comparing the conversion result with the determination reference signal. Therefore, the set level of the judgment reference signal must be a value that matches the observation conditions such as the appearance of the observed object and the illuminance of the light source.
Therefore, in the conventional object recognition device, at the time of designing, the shape, color, and gloss of the observed object, the background color when the observed object is viewed from the television camera, the brightness, etc. are taken into consideration for the observed object. It is designed to determine the illuminance of the light source.

As described above, the signal level of the determination reference signal is an important condition that determines the recognition accuracy of the object recognition device.Therefore, conventionally, the object recognition device should be manufactured at the time of its manufacture so that it conforms to the standard observation conditions selected at the time of design. It has been so arranged that the signal level cannot be simply and significantly changed after the adjustment and setting are made.

However, in reality, when the conditions under which the camera images the object to be observed have changed significantly from the conditions at the time of manufacturing or adjusting the object recognition device, or when the object to be observed has a shape or color that does not satisfy the design conditions. There may be a case where an object to be observed must be observed, and in such a case, in the past, an object designed to have a judgment reference signal satisfying the new condition as an object recognition device. There was the inconvenience of having to prepare a recognition device separately.

The present invention has been made in consideration of the above points, and as the signal level of the determination reference signal, the object recognition accuracy of the object recognition device is improved by maintaining the optimum value at the time of design as in the conventional case. If you want to maintain a high value and observe an object under observation conditions that are different from the design conditions of the object recognition device, propose an object recognition device that can be easily adapted to this. It is what

[Means for solving problems]

In order to solve such a problem, in the present invention, the object detection signal DD representing the signal level of the video signal VDIN obtained by imaging the observed object 4 by the television camera 3 in the driving operation mode is determined by the determination means. 8, the state of the observed object 4 is judged based on whether the object detection signal DD is within a predetermined judgment range by comparing with the judgment reference signal RG given from the judgment reference signal generating means 9. In the object recognition apparatus 1, the judgment reference signal generation means 9 supplies the judgment reference signal RG capable of changing the judgment range WG to the judgment means 8, and the judgment means 8 observes as a standard sample in the reference signal setting mode. An object detection signal DD obtained by picking up an image of the object 4 with the television camera 3 is set according to the currently applied determination reference signal and a predetermined signal. By comparing with the first determination range having the bell range WG, it is determined whether or not it matches the predetermined reference determination result of the observed object 4 as the standard sample, and when it does not match. , The object to be observed as a standard sample is limited to a second determination range narrower than a predetermined signal level range WG by changing the determination reference signal RG of the determination reference signal generation means 9 after determining that the object is unacceptable. By comparing the object detection signal DD obtained by imaging 4 with the television camera 3 with the second determination range, it is determined whether or not it matches the reference determination result.

[Action]

In the reference signal setting mode, the television object camera 3 captures an image of the observed object 4 as a standard sample. The object 4 to be observed as the standard sample is set in such a state that a predetermined judgment result, for example, a “defective” judgment result is obtained when the television camera 3 takes an image under standard observation conditions. There is. Therefore, if the object to be observed as the standard sample is imaged by the television camera 3 under the standard observation conditions, the determination circuit 8 can correctly obtain the predetermined determination result.

On the other hand, when the judgment circuit 8 cannot obtain a correct judgment result, it means that the observation condition of the observed object 4 by the television camera 3 is different from the standard observation condition. The judging means 8 gives a judgment range changing signal CH to the judging reference signal generating means 9.

In this way, the judgment range of the judgment reference signal RG supplied from the judgment reference signal generating means 9 to the judgment circuit 8 is changed and controlled, and the judgment means 8 executes the judgment operation by the judgment reference signal RG after the change control. It becomes a state. As a result, if the determination means 8 obtains a determination result that matches the predetermined determination result for the observed object, that means
The judgment range of the judgment reference signal RG supplied to the judgment means 8 is adapted to the observation condition for the observed object currently being observed. Therefore, if the operation mode is switched in this state, the judgment means 8 is correct. The determination operation can be performed.

〔Example〕

 An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, an object recognition circuit 1 receives a video signal VDIN obtained by imaging an object 4 to be observed by a television camera 3 in a sample hold circuit 5. The sample-hold circuit 5 extracts a signal portion corresponding to a predetermined observation position in the input video signal VDIN at the timing of the sample-hold pulse signal SH generated in the timing control circuit 6, samples and holds it, and outputs its output as an analog signal. Supply to the digital conversion circuit 7. The analog-digital conversion circuit 7 supplies the object detection data DD obtained by converting the sample hold output into a digital signal by the sampling pulse signal SP in synchronization with the sample hold operation of the sample hold circuit 5 to the determination circuit 8. .

In the case of this embodiment, the timing control circuit 6 receives the input video signal VDIN of a portion corresponding to a predetermined plurality N of observation areas on the screen imaged by the television camera 3 and reaches the sample hold circuit 5. At this timing, the sample hold pulse signal SH is generated, and thus the judgment circuit 8 receives the digital data representing the signal level (hence, the brightness level) of the input video signal VDIN corresponding to the N observation regions. The object detection signal of DD is sequentially supplied.

The determination circuit 8 receives the determination reference signal RG, which is a reference signal corresponding to each object detection data DD, from the determination reference signal generation circuit 9, and the value of the signal level represented by the object detection data DD is set for each object detection data. It is determined whether or not it is within a predetermined reference signal level range, and when it is, a "good" determination result is obtained, and when it is not, a "bad" determination result is obtained.

Thus, the determination circuit 8 that has obtained N determination results makes an overall determination of these determination results and, for example, when a predetermined number or more of “good” results are obtained, the object that indicates that the observed object 4 has no abnormality. When the recognition output OBJ is transmitted and the number of "good" results is not more than the predetermined number, the object recognition output OB indicating that the observed object 4 has the defect 4X is output.
Send J.

The above configuration is a portion that operates when the object recognition circuit 1 is in the operation mode. The operation mode of the object recognition circuit 1 is
This is performed by the object recognition circuit 1 as a whole responsively operating based on the command signal COM supplied when the operator operates the operation mode switch 11A in the operation input circuit 11.

The operation input circuit 11 uses the operation mode switch 11A.
In addition to the standard signal setting mode switch 11B,
When the reference signal setting mode switch 11B is operated by the operator, the object recognition circuit 1 is set in the reference signal setting mode by the operation command signal COM given from the operation input circuit 11. At this time, the determination circuit 8 supplies the determination range change signal CH to the determination reference signal generation circuit 9, and thereby further controls the signal level of the determination reference signal RG sent from the determination reference signal generation circuit 9.

In the reference signal setting mode, when the television camera 3 images the observed object 4 having the defect 4X, the signal level of the object detection data DD supplied to the determination circuit 8 based on the input video signal VDIN is Object recognition circuit 1
When the decision circuit 8 is in a state of making an erroneous decision because it does not conform to the design condition of No. 3, the correct decision result can be obtained by changing the decision range of the decision reference signal RG. In order to realize such operation in the operation mode in which the judgment reference signal generating circuit 9 is shown in FIG.
The determination reference signal RG can be generated by sequentially executing the processing steps shown in (B) and (C).

First, the judgment reference signal generation circuit 9 executes the first processing step in the reference signal setting mode to thereby generate the second reference signal.
As shown in the figure (A), as the judgment signal level (voltage) of the judgment reference signal RG, the judgment range signals + R1 and -R1 having a value of ± 25 [%] centering on the reference level V _REF.
Have. This first determination range signal + R1 and -R1
Is selected as a value that satisfies the design condition of the object recognition circuit 1, and the value of the object detection data DD is the first determination range signal + R.
When in the range WG of 1 to -R1, the determination circuit 8 generates a "good" determination result, whereas the object detection data DD is higher than the upper limit determination range signal + R1 in the signal level range WN1,
Or lower limit judgment range signal-signal level range W lower than R1
When it is N2, the decision circuit 8 is adapted to obtain a "bad" decision result.

In addition to this, the judgment reference signal generation circuit 9 has a judgment signal level of ± 12.5 [%] centering on the reference level V _REF as the second judgment range signals + R2 and −R2, and further the third judgment The range signals + R3 and -R3 have a determination signal level of ± 6.25 [%] with the reference level V _REF interposed therebetween.

Here, the determination reference signal generation circuit 9 supplies the first determination range signals + R1 and −R1 to the determination circuit 8, and further, the object detection data DD based on the observed object 4 having the defect 4X is supplied. In this state, when the determination circuit 8 erroneously makes an observation state in which a “good” determination result is generated, this means that the current observation condition is the object recognition circuit 1
It means that the product is in a rejected state that does not meet the design conditions of. Therefore, as the next processing step, the determination circuit 8 switches the determination reference signal generation circuit 9 from the first determination range signals + R1 and -R1 to the second determination range signals + R2 and -R2 as the next processing step. As a result, the width of the “good” determination range WG is reduced in the direction of the reference level V _REF , as shown in FIG. 2 (B).
As a result, the pass / fail judgment conditions are further tightened.

Further, as for the third judgment range signals + R3 and -R3, the judgment reference signal generating circuit 9 sends the judgment range signals + R2 and -R2 as shown in FIG. Object detection data D based on the observed object 4
When D is supplied and the decision circuit 8 is in an observation state in which a “good” decision result is erroneously generated, this means that the current observation conditions match the design conditions of the object recognition circuit 1. Do not mean that you are in a rejected state. Therefore, as the next processing step, the determination circuit 8 switches the determination reference signal generation circuit 9 in response to the determination range change signal CH to put the third determination range signals + R3 and -R3 into the state of being sent to the determination circuit 8. As a result, as shown in FIG. 2 (C), the “good” determination range WG in the determination circuit 8 is further reduced as compared with the state of FIG. 2 (B), and as a result, the pass / fail determination conditions are further tightened.

The determination reference signal generation circuit 9 uses the following processing steps as
In the state where the judgment range signals + R3 and -R3 having the most reduced "good" judgment range WG as shown in FIG. 2 (C) are supplied to the judgment circuit 8, the judgment circuit 8 still has the defect 4X. Object detection data DD for the observed object 4
In case of erroneously giving a “good” judgment result, the judgment impossible detection signal SJ is supplied to the operation input circuit 11 and, for example, the setting impossible display lamp 11C is turned on. This is because the determination circuit 8 cannot perform a correct determination operation even though the content of the determination reference signal RG is in the most reduced state as shown in FIG. 2 (C). In the case of a rejection state in which the judgment range cannot be automatically adjusted, even if the “good” judgment range WG is further reduced, the range WG is affected by noise components such as external noise and quantization noise. This is because the correct judgment operation cannot be expected to be received.

In the above configuration, when the television camera 3 is capturing an image of the observed object 4 under an observation condition that matches the design condition of the object recognition circuit 1 in the operation mode, the determination reference signal generation circuit 9 is set to the one shown in FIG. The determination reference signal RG having the first determination range signals + R1 and -R1 described in (A) is supplied to the determination circuit 8, and the determination circuit 8 determines "good" by the determination range signals + R1 and -R1. "Judgment range W
By determining whether G has a value of the object detection data DD, it is determined whether or not there is a defect in the observed object, and the object recognition output OBJ is transmitted.

In such an operation mode, the operator can switch the object recognition circuit 1 to the reference signal setting mode by operating the reference signal setting mode switch 11B of the operation input circuit 11. At this time, the observed object 4 having the defect 4X is imaged by the television camera 3. This observed object 4 uses a standard sample which should be judged by the object recognition circuit 1 to have a defect 4X, and accordingly, the television camera 3
If the observation condition according to (3) conforms to the design condition, the judgment circuit 8 must surely generate the "defective" judgment result.

In this operating state, if the determination circuit 8 produces a "defective" determination result, the output level of the object detection data DD is
The judgment range signals + R1 and -R1 shown in FIG. 2 (A) have such signal levels as to fall within the "defective" judgment ranges WN1 and WN2. At this time, the judgment circuit 8 sends the judgment range change signal CH. As a result, the judgment reference signal generating circuit 9 continues to send the judgment reference signal RG consisting of the judgment range signals + R1 and -R1. Thus, the setting operation in the reference signal setting mode is completed, and the object recognition circuit 1 practically determines the object detection data D having a signal level satisfying the design condition.
With D obtained, the object recognition operation can be performed.

On the other hand, as shown in FIGS. 2 (A), (B), and (C), the signal level of the object detection data DD is, for example, the determination range signal + R2 and In the case where it occurs between + R3, the judgment reference signal generation circuit 9, as shown in FIG.
Judgment reference signal RG consisting of judgment range signals + R1 and -R1
, The determination circuit 8 generates a “good” determination result and supplies the determination range change signal CH to the determination reference signal generation circuit 9. At this time, the judgment reference signal generating circuit 9
Changes the content of the judgment reference signal RG from the state of FIG. 2 (A) to + R2 and −R2 shown in FIG. 2 (B), thus reducing the “good” judgment range WG.
Based on the above, the determination circuit 8 executes the determination operation.

However, even in this state, since the signal level of the object detection data DD is still in the “good” determination range WG, the determination circuit 8 again generates the “good” determination result and the determination range change signal C is generated.
H is supplied to the determination reference signal generation circuit 9 again. Therefore, the determination reference signal generation circuit 9 determines the content of the determination reference signal RG from the determination range signal + R3 shown in FIG. 2 (B) to FIG. 2 (C).
And -R3. Therefore, the “good” determination range WG of the determination reference signal RG is further reduced, so that the signal level of the object detection data DD enters the “defective” determination range WN1 (FIG. 2 (C)). Circuit 8 produces a "bad" determination result.

At this time, the judgment circuit 8 does not send the judgment range change signal CH, and accordingly, the judgment reference signal generation circuit 9 also determines the judgment reference signal RG.
As a result, the determination range signals + R3 and -R3 are continuously output. Thus, the operation of the reference signal setting mode is completed, and thereafter, the judging circuit 8 executes the operation of detecting the presence / absence of a defect by using the judging reference signal RG composed of the judging range signals + R3 and -R3 as shown in FIG. Will be done.

This state means that when the observed object 4 having the defect 4X is actually imaged by the television camera 3, the determination reference signal RG of the determination circuit 8 is set again so as to adapt to this. Therefore, the object recognition circuit 1 is performing the correct determination operation based on the actually measured value in practical use. Therefore, even under the observation condition that only the object detection data DD having a signal level insufficient as the design condition is obtained because the imaging condition of the observed object of the television camera 3 does not satisfy the design condition. The object recognition circuit 1 can be adjusted to the condition that a correct judgment result is generated under the observation condition different from the design condition.

On the other hand, as shown in FIG. 2C, when the “defective” determination result is still not obtained in the determination circuit 8 even though the “good” determination range WG is reduced to the minimum,
The determination circuit 8 supplies the determination range change signal CH to the determination reference signal generation circuit 9 again, whereby the unsettable detection signal S
J is generated, and thereby the unsettable display lamp 11C is turned on. Therefore, looking at this lighting display, the operator
Under the current observation conditions of the television camera 3, it can be reliably and easily determined that the object recognition device cannot perform a correct object recognition operation.

When the observation condition is changed and the reference signal is set again after the reference signal is set once, the operation command signal COM is sent to the object recognition circuit 1 by operating the reset switch 11D of the operation input circuit 11. Just supply it. At this time, the object recognition circuit 1 performs a reset operation as a whole,
The judgment reference signal generating circuit 9 returns to the state shown in FIG.

[Effect of the Invention] As described above, according to the present invention, since the observation condition of the object to be observed by the television camera 3 does not satisfy the design condition, the signal level of the object detection data DD supplied to the determination circuit 8 is , If the signal level at design time is not reached,
Since the determination reference signal RG can be changed so as to be adapted to the observation condition, it is possible to obtain an object recognition device having good adaptability to changes in the observation condition. In this way, the determination reference signal RG can be set based on the actual measurement value obtained from the observed object, so that the risk of impairing the reliability of the object recognition device can be effectively avoided.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the object recognition apparatus according to the present invention, and FIG. 2 is a schematic diagram used for explaining the judgment reference signal generating circuit 9. 1 ... Object recognition circuit, 3 ... Television camera, 4 ...
... Observed object, 4X ... Defect, 8 ... Judgment circuit, 9 ...
Judgment reference signal generating circuit, 11 ... Operation input circuit.

Claims (1)

[Claims] 1. A judgment reference provided by a judgment reference signal generating means in the judgment means, an object detection signal representing a signal level of a video signal obtained by picking up an object to be observed by a television camera in a driving operation mode. In the object recognition device configured to determine the state of the observed object based on whether or not the object detection signal is within a predetermined determination range as compared with a signal, the determination reference signal generating means determines The judgment reference signal capable of changing the range is supplied to the judgment means, and the judgment means obtains the object detection signal obtained by imaging the observed object as the standard sample with the television camera in the reference signal setting mode. Is compared with a first judgment range having a predetermined signal level range set by the judgment reference signal currently given, And a first processing step for determining whether or not the object to be observed as a predetermined reference determination result matches, and when it does not match, change control of the determination reference signal of the determination reference signal generating means is performed. The object detection signal obtained by imaging the observed object as the standard sample with the television camera by limiting the second judgment range narrower than the predetermined signal level range by the second judgment range And a second processing step for determining whether the predetermined determination range to be used in the driving operation mode is determined by comparing with the above reference determination result. Object recognition device.