JPH0443232B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an object recognition device, and in particular, detects the presence or absence of an object based on a video signal obtained by imaging an object to be recognized using a television camera. It is possible to observe the condition of an object, such as the presence or absence of defects.

[Conventional technology]

As shown in FIG. 3, this type of object recognition device has a plurality of observation areas D1 to D, for example, four observation areas D1 to D on the ERA on the screen captured by a television camera.
4 in advance, and determines whether the signal level of the video signal (that is, the level of the luminance signal) corresponding to each observation area is within a predetermined judgment reference level. A device has been proposed that recognizes the presence or absence of a defect in each part of an object.

[Problem that the invention seeks to solve]

The principle of an object recognition device having such a configuration is to convert the amount of reflected light that reaches the camera from the observed object into the brightness of a video signal, and to obtain an object recognition output by comparing the conversion result with a determination reference signal. Therefore, the set level of the determination reference signal must be a value that matches the observation conditions such as the appearance of the object to be observed and the illuminance of the light source. Therefore, when designing conventional object recognition devices, consideration is given to the shape, color, and gloss of the observed object, as well as the color and brightness of the background when the observed object is viewed from a television camera. It is designed to determine the illuminance of the light source.

In this way, the signal level of the judgment reference signal is an important condition that determines the recognition accuracy of an object recognition device, so conventionally, when manufacturing an object recognition device,
Once the signal level has been adjusted and set to match the standard observation conditions selected at the time of design, the signal level is simply and not significantly changed.

However, in practice, there are cases where the conditions under which the camera images the observed object have changed significantly from the conditions under which the object recognition device was manufactured, or where the observed object has a shape, color, etc. that does not satisfy the design conditions. A case may occur in which it is necessary to observe an object to be observed, and in such a case, the correct object recognition operation will not be performed, so countermeasures such as increasing the observation conditions, for example, the illuminance of the light source, are required. However, conventionally, there has been no means to check whether the observation conditions of current television cameras satisfy the conditions at the time of design, or in other words, whether or not they are performing correct object recognition operations. Therefore, there was a problem with the judgment results that left some concerns.

The present invention has been made in consideration of the above points, and
The present invention attempts to propose an object recognition device that allows an operator to reliably and easily recognize an observation area and its distribution that cannot be determined.

[Means for solving problems]

In order to solve this problem, in the first invention, out of the video signal VDIN obtained by imaging the object 4 to be observed by the television camera 3,
The signal level of the signal portion corresponding to the predetermined observation areas D1 to D4 is determined by the determination circuit 8 as a determination reference signal.
In an object recognition device configured to determine the presence or absence of an abnormality in an observation area by comparing with RG, a video signal VDIN is obtained from a monitor 23 that displays a video signal VDIN on a display screen DES in a test mode and a determination circuit 8 in a test mode. and a cursor pattern display control unit 21 that generates a cursor pattern signal CSS based on the undeterminable detection signal DEN, and in the test mode, the object to be observed 4 as a standard sample whose presence or absence of defects is known in advance is displayed by the television camera 3. When the determination circuit 8 obtains an abnormality determination result that does not match the presence or absence of the defect, the determination circuit 8
By generating the undetermined detection signal DEN from the cursor, the cursor on the display screen DES of the monitor 23 is moved to the observation area position where the abnormality determination result was obtained or its vicinity.

Further, in the second invention, in addition to the monitor and cursor pattern display control unit 21 used in the first invention, an observation area D1 in the test mode is provided.
A test mode data forming circuit 34 that forms data representing the signal level of the signal portion corresponding to ~D4.
A state is obtained in which the object to be observed 4 is imaged by the television camera 3 in the test mode, and the first test data is input into the test mode data forming circuit 34, and the object to be observed 4 is removed. and input the second test data into the test mode data forming circuit 34, and supply the data of the difference between these first and second test data to the determining means 8,
When an abnormality determination result is obtained in which the value of the difference data does not exceed a predetermined reference level, the determination means 8
By generating an undeterminable detection signal DEN from the monitor 23, the cursor on the display screen DES of the monitor 23 is moved to or near the observation area position where the abnormality determination result was obtained.

[Effect]

In the first invention, in the test mode, the object to be observed 4 is used as a standard sample whose presence or absence of defects is known in advance.
is imaged by the television camera 3. As a result, when the judgment result of the judgment circuit 8 does not match the presence or absence of known defects in the observed object 4 as the standard sample, if the object is recognized under the observation conditions, the judgment will be incorrect. Therefore, the determination circuit 8 generates an undeterminable detection signal DEN indicating that determination is impossible under the observation conditions.

At this time, the cursor pattern display control section 21
On the display screen DES of the monitor 23, move the cursor to the position of the observation area where the abnormality determination result was obtained or its vicinity, and check the fact that the determination is impossible and the distribution of the observation area where the determination is not possible.
3 can be displayed on the display screen DES.

Further, in the second invention, the input video signal VDIN is set in two states: a state in which the observed object 4 is imaged by the television camera 3 in the test mode, and a state in which the observed object 4 is removed.
The test data based on the above is taken into the test mode data forming circuit 34, and the data of the difference between these two test data is sent out from the test mode data forming circuit 34.

In this way, the test mode data forming circuit 3
The difference data obtained from 4 shows that the reflected light reflected by the observed object 4 is reflected by the television camera 3.
The brightness level of the input video signal VDIN when the reflected light is incident on the television camera 3 (that is, the maximum brightness level), and the brightness level of the input video signal VDIN when the reflected light is not incident on the television camera 3 (that is, the minimum brightness level) It means the difference between The difference between the maximum brightness level and the minimum brightness level can also be said to represent the so-called dynamic range when the object recognition device executes the object recognition operation, and the brightness of the input video signal VDIN during the actual object recognition operation. The level will be between the maximum brightness level and the minimum brightness level.

However, if the difference between the maximum brightness level and the minimum brightness level is too small, the determination circuit 8 will not be able to perform the determination operation with high accuracy. Incidentally, the determination circuit 8 performs a determination operation based on the difference in brightness level in principle, but if the difference is small, it will not be possible to obtain a correct determination result due to the influence of noise components.

Therefore, when the difference between the maximum brightness level and the minimum brightness level is small, the determination circuit 8 generates an undeterminable detection signal DEN, and the cursor pattern display control unit 21 moves the cursor to the undeterminable observation area position or its vicinity. Move and display.

〔Example〕

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

First Embodiment In FIG. 1, reference numeral 1 denotes an object recognition circuit, which receives a video signal VDIN obtained by imaging an observed object 4 with a television camera 3 into a sample and hold circuit 5. The sample and hold circuit 5 extracts and samples and holds a signal portion corresponding to a predetermined observation area from the input video signal VDIN at the timing of the sample and hold pulse signal SH generated in the timing control circuit 6, and converts the output into an analog signal. -supply to digital conversion circuit 7;
The analog-digital conversion circuit 7 converts the sample and hold output into a digital signal using the sampling pulse signal SP in synchronization with the sample and hold operation of the sample and hold circuit 5, and supplies object detection data DD to the determination circuit 8. .

In this embodiment, the timing control circuit 6 is
As described above with reference to FIG. The sample-and-hold pulse signal SH is generated at the timing when the pulse signal SH arrives at the circuit 5, and thus the determination circuit 8 receives the signal level (therefore, the luminance) of the input video signal VDIN corresponding to these four observation areas D1 to D4. An object detection signal consisting of digital data DD representing the level) is sequentially supplied.

The determination circuit 8 receives a signal from the determination reference signal generation circuit 9,
A determination reference signal RG consisting of a reference signal corresponding to each object detection data DD is received, and a judgment is made for each object detection data as to whether or not the signal level value represented by the object detection data DD is within a predetermined reference signal level range. When it is found, a "good" judgment result is obtained, and when it is not, a "bad" judgment result is obtained.

That is, as shown in FIG. 4, the judgment reference signal RG has a judgment range +R to -R of a predetermined ratio (for example, ±25 [%]) with respect to the reference level voltage V _REF , and +
A "good" judgment range WG is formed between R and -R, and "bad" judgment ranges WN1 and WN2 are formed in the range of the voltage level above +R or below -R, and the object detection data DD is judged as "good". When it is in the range WG, a "good" judgment result is obtained, and a "bad" judgment result is obtained in the range WN1 and
When it is at WN2, a "defective" judgment result is obtained.

The determination circuit 8 that has thus obtained four determination results,
For example, when a predetermined number of "good" results are obtained by comprehensively judging these judgment results, an object recognition output OBJ indicating that there is no abnormality in the observed object 4 is sent, and in response, the predetermined number of "good" results are obtained. If only the following number of "good" results are obtained, the object recognition output indicates that the observed object 4 has a defect 4X
Send OBJ.

The above configuration is a part that operates when the object recognition circuit 1 is in the operation mode. This is carried out by the responsive operation of the object recognition circuit 1 as a whole based on the COM.

In addition to the above configuration, the object recognition circuit 1 has the following configuration that operates in the test mode. That is, the operation input circuit 11 includes a test mode switch 11.
B is provided, and this test mode switch 11B
The operation mode of the object recognition circuit 1 is switched to the test mode by the command signal COM generated when the object recognition circuit 1 is operated.

In this test mode, the television camera 3 is made to image an object to be observed 4 as a standard sample having a defect at a predetermined position. At this time, based on the input video signal VDIN sent from the television camera 3, the sample and hold circuit 5 and the analog-to-digital conversion circuit 7
When the television camera 3 is observing the observed object 4 under observation conditions that satisfy the standard setting conditions, the object detection data DD obtained through The signal level is in the "defective" judgment range WN1 or WN2 in Figure 4, and therefore the judgment circuit 8 indicates "defective".
Generates a judgment result.

However, when the observation conditions for the observed object 4 by the television camera 3 do not satisfy the standard setting conditions (for example, when observing with insufficient illuminance of the light source), the signal level of the object detection data DD is , the state falls within the "good" judgment range WG in FIG. At this time, the determination circuit 8 generates a "good" determination result even though the observed object 4 has the defect 4X.

This state occurs even though there is no failure in the object recognition circuit 1, due to inappropriate observation conditions.
This means that the object recognition circuit 1 is in a state where it cannot correctly perform a determination operation, and at this time, the determination circuit 8 generates a determination failure detection signal DEN and supplies it to the cursor pattern display control section 21 .

This undeterminable detection signal DEN is configured to be generated for each signal portion sampled and held in the sample and hold circuit 5 of the input video signal VDIN, and thus is transmitted to the television camera 3 as described above with reference to FIG. As a result, undeterminable detection signals DEN are transmitted for each of the four observation areas D1 to D4 in the observed observation screen ERA.

On the other hand, the input video signal of the television camera 3
VDIN is supplied via a mixing circuit 22 to a monitor 23 made of, for example, a cathode ray tube, so that the observation screen ERA described above with reference to FIG. 3 is reproduced on the display screen DES of the monitor 23.

The cursor pattern display control section 21 controls the monitor 2
The cursor 24 is displayed on the display screen DES in step 3 as an undeterminable position display means, and when the undeterminable detection signal DEN is not generated, the display screen
A cursor display signal CSS is generated and supplied to the mixing circuit 22 at a timing such that, for example, the upper left corner position of the DES is fixedly displayed as the home position, and thus the cursor display signal is applied to the input video signal VDIN.
By superimposing CSS, the cursor 2 can be placed at the home position of the display screen DES on the monitor 23.
Display 4.

In addition to this, the cursor pattern display control section 2
1 is an undeterminable detection signal for any one or more of observation areas D1, D2, D3, and D4.
When DEN occurs, as shown by the dotted line in FIG. 3, the cursor display signal CSS is displayed at a timing that displays the cursor 24 in the vicinity of the observation area where the undeterminable detection signal DEN has occurred, for example at the upper position. Send out.

Thus, on the display screen DES of the monitor 23,
When the cursor 24 moves from the home position to the display position, the operator can easily visually confirm that the judgment circuit 8 has generated an undecidable result for an observation area near the movement destination. There is.

In the above configuration, when the operator operates the test mode switch 11B of the operation input circuit 11 to switch the operation mode of the object recognition circuit 1 to the test mode, the observed object 4 as a standard sample having a defect 4X is detected. When the television camera 3 captures an image, the display screen DES corresponding to the observation screen ERA observed by the television camera 3 is displayed on the monitor 23.
A cursor display signal that is displayed on the top and generated in the cursor pattern display control section 21
A cursor 24 is displayed on the display screen DES by CSS.

In this state, the determination circuit 8 originally determines that the observed object 4 has the defect 4X, and therefore the observation conditions are such that a "defective" determination result is obtained. When a "good" judgment result is generated for one or more of D4, this means that a correct judgment cannot be made for the observation area, and therefore the judgment circuit 8 generates a "good" judgment result for one or more of D4. An undeterminable detection signal DEN is sent to the cursor pattern display control section 21 at the timing when the television camera 3 scans and enters the observation area where the determination result has been obtained.

At this time, the cursor pattern display control section 21
A cursor display signal CSS is generated to move and display the cursor 24 from the home position to the upper position of the undeterminable observation area.

Therefore, the operator must check the display screen of the monitor 23.
Observation areas D1 to D by visually observing the DES
It is possible to visually confirm that there is at least one undeterminable position among 4, and it is also possible to easily determine where in the observation screen ERA the undeterminable position is.

In practice, if there is at least one undeterminable object in the observation area, the object recognition circuit 1 will not be able to perform a correct determination operation, and therefore, unless the observation conditions for the observed object 4 by the television camera 3 are improved, It can be reliably recognized that correct object recognition cannot be performed under the observation conditions in the test mode.

In addition, since the position and distribution of undeterminable observation areas can be visually confirmed, the operator can easily understand how to improve observation conditions. Incidentally, the observation screen
Parts of the ERA that cannot be determined may be caused by, for example, uneven illumination of the observed object 4, careless shadows, or areas with different reflectances. In many cases, there are disadvantages in the observation conditions, such as when the ERA is inconvenient, and when undeterminable areas are distributed over almost the entire observation screen ERA, the amount of light irradiated from the light source to the observed object 4 may be insufficient. It is possible that

In this way, the operator can actually check the operating state of the object recognition circuit 1 in the test mode, so that even though the object recognition circuit 1 is operating normally, the operator can It can be easily and reliably confirmed that a correct determination result cannot be obtained because the observation conditions for the object 4 are not appropriate, and thus the reliability of the object recognition circuit 1 can be further improved.

Second Embodiment FIG. 2 shows another embodiment of the present invention.
In this case, as shown by assigning the same reference numerals to parts corresponding to those in FIG.
is inserted.

When the test mode switch 11B of the operation input circuit 11 is operated, the object detection data forming circuit 31 changes the data from the operation mode end OP side to the test mode end TE.
It has switch circuits 32 and 33 that switch in conjunction with the operation mode.
and 33 are switched to the operation mode end OP side, the output of the analog-to-digital conversion circuit 7 is supplied to the determination circuit 8 from the operation mode end OP of the switch circuit 32 through the operation mode end OP of the switch circuit 33. Ru.

On the other hand, in the test mode, the switch circuits 32 and 33 are switched to the test mode end TE side, so that the output of the analog-digital conversion circuit 7 is passed through the test mode end TE of the switch circuit 32 to form test mode data. circuit 3
4, and its output is supplied to the determination circuit 8 through the test mode terminal TE of the switch circuit 33.

The test mode data forming circuit 34 includes an object presence data memory 35 and an object absence data memory 36.
and a subtraction circuit 37 for subtracting the outputs of these memories 35 and 36, and the subtraction output of the subtraction circuit 37 is sent to the determination circuit 8 through the test mode terminal TE of the switch circuit 33.

The data memory with object 35 and the data memory without object 36 are connected to the operation input circuit 11 in the test mode.
By switching the data input switch 11C, the output data of the analog-to-digital conversion circuit 7 can be taken in alternately as required by the operator's operation.

In other words, the operator
With the observed object 4 having no defects set in the observation area, the output of the analog-digital conversion circuit 7 can be input to the object data memory 35 by operating the data input switch 11C.

In this state, the operator
By operating the data input switch 11C while the object is removed from the observation field of the television camera 3, the output data of the analog-digital conversion circuit 7 can be written into the objectless data memory 36.

In the above configuration, when the operator operates the operation mode switch 11A of the operation input circuit 11, the switch circuits 32 and 33 are switched to the operation mode end OP side, so that the object that can be observed by the television camera 3 is The determination circuit 8 can determine whether or not the observed object 4 has a defect, and an object recognition output OBJ representing the determination result can be obtained.

On the other hand, when the operator operates the test mode switch 11B, the object recognition circuit 1 goes into the test mode, and the switch circuits 32 and 33 are switched to the test mode end TE side. In this state,
The operator sets an observed object 4 that does not have defects in the observation field of the television camera 3, and
When the data input switch 11C is operated, an analog signal is generated corresponding to each observation area D1 to D4 based on the input video signal VDIN obtained from the television camera 3 based on the defect-free observed object 4.
The data obtained in the digital conversion circuit 7 is written into the object data memory 35.

In this state, the operator
is removed from the observation field of the television camera 3, and the data input switch 11C is operated. Since there is no observed object 4 for the television camera 3 to photograph, the input video signal VDIN corresponding to the background is sent out. Corresponding data is obtained at the output of the analog-to-digital conversion circuit 7 and is written into the objectless data memory 36.

In this way, data when the observed object 4 is present and data when it is absent are written in the data memories 35 and 36, respectively, and these are subtracted by the subtraction circuit 37. As a result, the output terminal of the subtraction circuit 37 shows the brightness level of the input video signal VDIN when the observed object 4 is present in the observation area of the television camera 3 (that is, the maximum brightness level), and the brightness level of the input video signal VDIN when there is no observed object 4. Data corresponding to the difference in brightness from the brightness level (that is, the minimum brightness level) is obtained, and this data is supplied to the determination circuit 8.

In this embodiment, the judgment reference signal generation circuit 9
In the test mode, the determination circuit 8 sends out a reference level signal RG corresponding to the difference in luminance level, and thus the determination circuit 8 determines that the luminance difference represented by the output of the object detection data forming circuit 31 is the reference level signal RG. It is determined whether the value is larger than that, and if it is smaller, the undeterminable detection signal DEN
is generated and supplied to the cursor pattern display control section 21. This determination is executed for each of the observation areas D1 to D4 set in the observation screen ERA, and thus the cursor pattern display control unit 21 determines the observation area where the undeterminable detection signal DEN has occurred in the same manner as described above with respect to FIG. By moving and displaying the cursor 24 in the vicinity of D1 to D4, when there is an observation area where the brightness difference is insufficient, the area and distribution are displayed.

Here, the determination of undeterminable by the determination circuit 8 is as follows:
The brightness level obtained when observing an observed object 4 with a defect with the television camera 3 is the brightness level when there is an observed object 4 without a defect in the observation area of the television camera 3, and the brightness level when there is no defective observed object 4 in the observation area of the television camera 3. data memories 35 and 36.
If the difference in the data written to is small, the brightness level at which the defect is based will fall between the small brightness differences. However, in order to correctly determine whether or not there is a defect-based brightness level between the brightness differences, the brightness difference needs to be equal to or higher than a predetermined limit level (eg, noise level) in practical terms. Therefore, the determination circuit 8 determines that it is undeterminable for the observation areas in which the difference in luminance is less than or equal to the required luminance difference stored in the memories 35 and 36, and sends out an undeterminable detection signal DEN.

Therefore, in this case, in the test mode, if there is an observation area on the observation screen ERA where the brightness difference is so small that it cannot be determined, its position and distribution will be monitored on the monitor 23.
With the display screen TES, it is possible to obtain an object recognition device that can be easily visually confirmed.

Note that in the above description, the determination circuit 8 is shared for both the driving mode and the test mode, but instead of this, it may be configured separately.

〔Effect of the invention〕

As described above, according to the present invention, on the observation screen ERA,
When there is an observation area that cannot be determined by the object recognition circuit 1, it is possible to easily obtain an object recognition device that can easily and reliably visually confirm the position and distribution of the observation area. It is possible to reliably judge whether conditions are suitable or not.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the object recognition device according to the present invention, FIG. 2 is a block diagram showing another embodiment of the object recognition device according to the present invention, and FIG. 3 is a block diagram showing an observation screen by a television camera. A schematic diagram showing the display screen, and FIG. 4 is a schematic diagram showing the determination level of the determination circuit 8. In FIG. 1... Object recognition circuit, 3... Television camera, 4... Observed object, 4X... Defect, 8... Judgment circuit, 9... Judgment reference signal generation circuit, 21...
Cursor pattern display control unit, 22...Mixing circuit, 23...Monitor, 31...Object detection data forming circuit, 34...Test mode data forming circuit,
35, 36...Data memory with object and without object.

Claims (1)

[Claims] 1. A television camera that images an observed object in an observation field and sends out a video signal, and a signal level of a signal portion of the video signal corresponding to a predetermined observation area as a determination reference signal. The presence or absence of defects in the observation area is determined by comparison, and is obtained by imaging an object to be observed as a standard sample whose presence or absence of defects is known in advance with the television camera in the test mode. a determination means that generates an undetermined detection signal when an abnormality determination result that does not match the presence or absence of the known defect is obtained based on the video signal; and a monitor that displays the video signal on a display screen in a test mode. and an observation area where the abnormality determination result was obtained by generating a cursor pattern signal based on the undeterminable detection signal obtained from the determination means in the test mode and superimposing it on the video signal input to the monitor. An object recognition device comprising: a cursor pattern display control unit that displays a cursor at or near the position. 2. A television camera that images the object to be observed in the observation field and sends out a video signal, and in test mode, based on the video signal, generates data representing the signal level of the signal portion corresponding to the observation area. , first test data formed with the observed object placed within the observation field of the television camera, and second test data formed with the observed object removed from the observation field. a test mode data forming means for capturing data and outputting data of the difference between the first and second test data; and comparing the signal level of a signal portion of the video signal corresponding to a predetermined observation area with a determination reference signal. In addition to determining the presence or absence of defects in the observation area,
a determination means for generating an undeterminable detection signal when an abnormality detection result in which the value of the difference data is not within a predetermined reference range; and a monitor for displaying the video signal on a display screen in a test mode. and an observation area where the abnormality determination result was obtained by generating a cursor pattern signal based on the undeterminable detection signal obtained from the determination means in the test mode and superimposing it on the video signal input to the monitor. An object recognition device comprising: a cursor pattern display control unit that displays a cursor at or near the position.