JP6048194B2 - Impact light emitting point detector - Google Patents

Description

This invention uses a device that fires a shell and a device that uses an image pickup device installed in the vicinity thereof, and generates a bullet that is generated when the shell is landed from an image obtained by shooting how the shell is fired and landed. It detects landing light emission by image processing, notifies the position information of the detected target to the device that fires the shell, and corrects the gun when the next bullet is fired from the difference between the target position and the landing position. is there.

In order to improve the accuracy of gun hits, high-precision gun control and accurate trajectory calculation from wind direction, wind speed, distance, etc. are required. Furthermore, for long-range guns, it is indispensable to have a gun correction technique that corrects the aim according to the degree of dislocation by looking at the impact of the shell.
In the impact light emitting point detection, a method using various image processing using image data obtained from an image pickup device installed in the vicinity of a shell projecting device has been proposed.
As an example of the method, using a distance measuring device such as a laser that measures the distance from the position of the gun to the target, the time required for the bullet to fly the distance to the target is calculated from the time the bullet is fired, and imaging is performed. There are some which extract only the image after the flight time has elapsed from the image data obtained from the machine to detect the impact light emission point (for example, see Patent Document 1).

JP 60-22608 (page 39, Fig. 2)

As described in Patent Document 1, a method using image data and distance data has been proposed, but there is a problem that it is expensive because a distance measuring device such as a laser is required.
Therefore, in the future, an impact light emission point detection device using only image data will be required. However, an impact light emission point detection device using only image data will produce a muzzle flame with high brightness as described later. It is necessary to increase the threshold for binarization so that false detections that are detected as targets and muzzle flames are not erroneously detected, so even if impact light emission actually occurs, binarization As a result, there is a problem that an accurate impact light emitting point cannot be detected.

The present invention has been made to solve such a problem, and provides a landing light emitting point detection device that can accurately measure the detection of a landing light emitting point only from image data without requiring distance data as in the prior art. For the purpose.

An impact light emission point detection device according to the present invention is an impact light emission point detection device that outputs position information where a bullet has landed using an image composed of a plurality of frames imaged by an imaging device over time. A landing light emission start determination circuit that determines whether or not the light has landed and started light emission, and the impact light emission start determination circuit compares standard deviations of luminance values in the image plane in the images before and after the frame. When the value obtained by dividing the standard deviation of the luminance value in the image plane in the subsequent image by the standard deviation of the luminance value in the image plane in the previous image is equal to or greater than a predetermined value, the shell is landed. It is determined that light emission has started, and the position information where the shell has landed is calculated and output using an image of a frame in which the value is equal to or greater than the predetermined value.

According to the impact light emission point detection device according to the present invention, by performing impact light emission start determination and muzzle flame disappearance determination from image data, image data after the start of impact light emission, or after muzzle flame disappearance By performing binarization processing and center-of-gravity measurement only on image data, it is possible to accurately measure the detection of impact light emission points.

It is a figure explaining the flow of a landing position detection process in the landing light emission point detection apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining transition of the standard deviation of the image which imaged from the launch of the bullet to the landing in Embodiment 1 of the present invention. It is a figure explaining the flow of the landing position detection process of the landing light emission point detection apparatus which concerns on Embodiment 2 of this invention. It is a figure explaining transition of the average value of the picture which picturized from the launch of a bullet to the landing in Embodiment 2 of the present invention. It is a figure explaining the fundamental structure of the apparatus at the time of performing the conventional impact light emission detection. It is an example of the image imaged before a shell discharge in the conventional apparatus structure. It is an example of the image which imaged the muzzle flame which generate | occur | produces at the time of a shell discharge in the conventional apparatus structure. It is an example of an image when a muzzle flame disappears in a conventional device configuration. It is an example of an image when impact light emission occurs in a conventional device configuration. It is an example of the image which binarized impact light emission in the conventional apparatus structure. It is a figure explaining the flow of the landing position detection process in the conventional landing light emission point detection apparatus.

First, a description will be given of a device configuration and a processing flow when performing conventional impact light emission detection.
FIG. 5 is a diagram for explaining a basic configuration of a device when performing conventional impact emission detection. In FIG. 5, the shell 4 is fired from the shell firing device 2 and flies toward the target 5. Image data captured by the imaging device 1 is sent to the impact light emitting point detection device 3. The position information of the impact light emission point detected by the impact light emission point detection device 3 is sent to the cannon ball firing device 2 and used for calculation of gun correction at the time of the next bullet firing.
At that time, the characteristics of the image captured by the imaging device 1 installed in the vicinity of the cannonball firing device until the cannonball 4 is fired and landed will be described below with reference to the drawings.
When the imaging device 1 captures from the bullet launch to the bullet landing, the image generally has the following flow.

FIG. 6 is an example of an image captured before the bullet is fired. In the state before the shell is fired, the target and its background are imaged.
FIG. 7 is an example of an image taken immediately after the shell is fired. Immediately after the cannonball 4 is fired, the generated muzzle flame 9 and the high-temperature gas 11 and the like generated therewith are imaged. The muzzle flame 9 is a flame generated as a result of combustion of the explosive, and is generated at a high temperature and in the vicinity of the image pickup device, so that it has a great influence on the image to be picked up. As shown in FIG. 7, most of the image is in a high brightness state.

FIG. 8 is an example of an image captured after a predetermined time has elapsed since the shell was fired. The muzzle flame 9 and the high-temperature gas 11 disappear as the heat diffuses over time and the temperature drops or is blown away by the wind. At this time, an image is captured in which the brightness of the entire image decreases while the brightness of the entire image decreases while the brightness of the entire screen increases immediately after the shell is fired.
FIG. 9 shows an example of an image in which landing luminescence emitted by the fired cannonball 4 is picked up and the impacted light emission emitted from the landed cannonball is captured. FIG. 10 is an example of an image obtained by binarizing the impact light emission image of FIG.
FIG. 11 is a diagram for explaining the flow of the landing position detection process in the conventional landing light emitting point detection device 3. In the conventional impact light emission point detection device 3, binarization processing is unconditionally performed on all the images described with reference to FIGS. 5 to 9, the center of gravity is measured from the binary image, and the coordinates are determined as the impact light emission points. It was detected as.
Therefore, it is necessary to increase the threshold for binarization so that the muzzle flame 9 having high brightness is detected as the target 5 and the muzzle flame 9 is not erroneously detected. Even if impact light emission occurs, binarization cannot be performed at all, and as a result, there is a problem that an accurate impact light emission point cannot be detected.

Embodiment 1
The impact light emission point detection apparatus according to Embodiment 1 will be described below with reference to the drawings.
FIG. 1 is a diagram for explaining the configuration of a landing light emitting point detection apparatus according to Embodiment 1 of the present invention and the flow of landing position detection processing.
The impact light emission point detection device 3 includes an impact light emission start determination circuit 17 that determines whether or not impact light emission has started, a binarization circuit 14 that binarizes the image data 6, and a binarized image A centroid measurement circuit 16 that measures the centroid of the binarized region using the binary image 15 is provided.
In FIG. 1, image data 6 obtained from the image pickup device 1 installed in the vicinity of the bullet projecting device 2 is sent to the impact light emitting point detection device 3. In the impact light emission point detection device 3, the image data 6 is binarized by the binarization circuit 14, and the binary image 15 is sent to the gravity center measurement circuit 16. The center-of-gravity measurement circuit 16 measures the center of gravity of the binarized area, and sends the coordinates to the bullet firing device 2 as the position information 7 of the impact light emitting point.
Also, for the image data 6 from the imaging unit 1, the impact light emission start determination circuit 17 determines the impact light emission start frame, and sends impact light emission start information 18 to the binarization circuit 14.
The binarization circuit 14 starts binarization processing based on the impact light emission start information 18.
Here, the impact light emission start determination is to determine whether or not the impact light emission shown in the image example FIG. 9 has started. The impact light emission start determination circuit 17 uses the following equation (1) to obtain the standard deviation of the luminance in the image plane for each frame from the obtained image, and satisfies the condition shown in the equation (1) after the bullet is fired. Then, it is determined that the frame that has been satisfied for the first time is the frame in which the impact light emission has started.

FIG. 2 is a diagram for explaining the time transition of the standard deviation of luminance in an image obtained from shooting of a bullet to landing. Since the standard deviation 19 of the image before the shell is shot is taken at the target point before being fired, the standard deviation is different depending on the environment of the target point, but does not change with time. .
Next, the standard deviation 20 of the brightness of the image during the muzzle flame is greatly reduced due to the muzzle flame 9 when the bullet is fired. This is because the brightness of the entire screen becomes high due to the occurrence of muzzle flame, so that there is no brightness difference at each location on the screen and the standard deviation is reduced.

Next, the standard deviation 21 of the luminance of the image in the process of disappearing the muzzle flame becomes smaller as a whole because the influence of the muzzle flame becomes smaller, and the standard deviation becomes larger as a whole. This is because in the process of disappearance of the muzzle flame, the way of flame disappearance and the distribution of high-temperature gas change depending on the surrounding environment, and the standard deviation also changes slightly depending on the behavior, but the influence of the muzzle flame disappears as a whole. Therefore, it approaches the standard deviation before the shells are fired.
The standard deviation 22 of the luminance of the image at the time of occurrence of impact light emission is impact light emission that occurs when a bullet hits, and the standard deviation greatly increases. This is because the impact light emission has a high luminance and appears only in a part rather than the entire image.

Here, the landing light emission start determination circuit 17 detects, based on the formula (1), a frame that first reaches a value above a certain value with an increase in the standard deviation as a frame in which the impact light emission has started.
Then, the landing light emission start determination circuit performs the binarization processing that makes the high-luminance portion that has been conventionally performed significant by the fact that the landing light emission has started, and the pixel region that is made significant The position information is notified using the center of gravity of the bullet as the bullet emission point of the shell.

As described above, in the impact light emission point detection device according to the first embodiment, it is determined whether or not impact light emission has started based on the determination formula using the standard deviation represented by the equation (1). . As shown by the standard deviation 21 of the brightness of the muzzle flame disappearance process in FIG. 2, the impact light emission start determination circuit 17 gradually increases in value while gradually changing in the muzzle flame disappearance process. The timing at which the standard deviation of the luminance value before and after the image frame exceeds a predetermined constant value is determined as the timing at which impact light emission starts.

According to the impact light emission point detecting device according to the present embodiment, the impact light emission due to the detection error or the threshold value for binarization that is detected with a high-luminance muzzle flame as a target. Even if this occurs, binarization cannot be prevented, and the detection of the landing light emission point can be accurately measured.

Embodiment 2. FIG.
According to the impact light emission point detection device according to the first embodiment, it is possible to detect the impact light emission point with high accuracy by preventing erroneous detection, but depending on the surrounding environment, in the muzzle flame disappearance process There may be a local fluctuation of the standard deviation, which may adversely affect the impact light emission start determination.
In the second embodiment, therefore, the impact light emission start determination is performed and the muzzle flame disappearance determination is also performed.

FIG. 3 is a diagram for explaining the configuration of the landing light emission point detection apparatus according to the second embodiment and the flow of landing position detection processing.
The impact light emission point detection device 3 according to the present embodiment includes a muzzle flame disappearance determination circuit 23 that determines whether or not a muzzle flame has disappeared, and a bullet that determines whether or not impact light emission has started. An arrival / emission start determination circuit 17, a binarization circuit 14 for binarizing the image data 6, and a centroid measurement circuit 16 for measuring the centroid of the binarized region using the binarized binary image 15 Is provided.
The muzzle flame disappearance determination circuit 23 determines a muzzle flame disappearance frame for the image data 6 from the imaging unit 1, and sends muzzle flame disappearance information 24 to the binarization circuit 14.
Based on the impact light emission start information 18 and the muzzle flame disappearance information 24, the binarization circuit 14 starts the binarization process on the condition that the disappearance of the muzzle flame has been completed and the impact light emission has started.

Here, the muzzle flame disappearance determination circuit 23 determines whether or not the muzzle flame shown in the image of FIG. 8 has disappeared. For the determination, an average luminance value is acquired for each frame from the obtained image, and after satisfying the condition indicated by the following equation (2), a frame that is satisfied for the first time is determined to be a frame in which the muzzle flame has disappeared. Equation (2) is used to determine whether or not a value obtained by dividing the average luminance value of the t-th frame image image by the average luminance value of the image before the bullet is less than or equal to a predetermined constant value K. It is.

FIG. 4 shows the transition of the average luminance value of the image from the time when the shell is fired until the impact light emission occurs.
The average brightness 25 of the image before projecting the bullet differs depending on the environment of the target point, but is a substantially constant value. The average brightness 26 of the image during muzzle flame generation is fixed to a high value when a cannonball is fired and muzzle flame is generated.
Next, the average brightness 27 of the image of the muzzle flame disappearing process decreases while changing to a small value, and stabilizes to a value close to that before the shell was fired. The average brightness 28 of the image at the time of occurrence of impact light emission increases greatly when a bullet hits and impact light emission occurs.

The muzzle flame disappearance determination circuit 23 detects a point where the influence of the muzzle flame shown in FIG. 12 is reduced and the average value is reduced to a value close to the level before the bullet is fired based on the equation (2).
The average value is less affected by the effects of muzzle flames on the part of the image taken compared to the standard deviation, and represents the tendency of the brightness of the entire screen, so the muzzle flames disappear. It is possible to stably grasp that the influence on the captured image has been reduced.

Thus, the impact light emission point detection apparatus according to the present embodiment includes the muzzle flame disappearance determination and the impact light emission start determination. As a result, depending on the surrounding environment, the local deviation of the standard deviation increases in the process of extinguishing the muzzle flame. The detection of impact light emission points is prevented by preventing false detections that are detected as targets, and the fact that binarization cannot be performed even if impact light emission occurs because the threshold for binarization is increased. It can measure with high accuracy.

It can be applied to an aiming shooting system that uses image processing for aiming point setting, and a highly accurate shooting system can be realized with a simple configuration.

DESCRIPTION OF SYMBOLS 1 Image pick-up device, 2 Cannonball launching device, 3 Bullet emission point detection device, 4 Cannonball, 5 Target, 6 Image data, 7 Position information, 8 Target in the imaged image, 9 Imaged muzzle flame, 10 Imaged Remaining muzzle flame, 11 Imaged hot gas, 12 Imaged impact light emission, 13 Imaged binary impact light emission, 14 Binary circuit, 15 Binary image, 16 Center of gravity measurement Circuit, 17 impact light emission start determination circuit, 18 impact light emission start information, 19 standard deviation of image before projectile launch, 20 standard deviation of image during muzzle flame occurrence, 21 standard deviation of image of muzzle flame disappearance process , 22 Standard deviation of image when impact light emission occurs, 23 Muzzle flame disappearance determination circuit, 24 Muzzle flame disappearance information, 25 Average brightness of image before launching fire, 26 Average brightness of image during muzzle flame occurrence, 27 Average brightness of the muzzle flame disappearance process 28 bullets deposition average luminance of the light emission generated at the time of the image.

Claims (4)

An impact light emitting point detection device that outputs position information where a shell has landed using an image composed of a plurality of frames captured by an imager over time,
An impact light emission start determining circuit for determining whether or not the bullet has landed and started light emission;
The impact light emission start determination circuit compares the standard deviation of the luminance value in the image plane in the image before and after the frame, and determines the standard deviation of the luminance value in the image plane in the subsequent image as the image plane in the previous image. When the value divided by the standard deviation of the brightness value is equal to or greater than a predetermined value, it is determined that the bullet has landed and started to emit light,
An impact light emitting point detection device that calculates and outputs position information where a bullet has landed using an image of a frame in which the value is equal to or greater than the predetermined value . A muzzle flame extinction circuit that determines whether or not the muzzle flame has disappeared,
The muzzle flame extinguishing circuit compares the average value of the luminance value in the image plane of the frame after the bullet is fired with the average value of the luminance value in the image plane of the frame before the bullet is fired. 2. The muzzle flame is determined to have disappeared when a value obtained by dividing an average value of brightness values by an average value of brightness values before firing a bullet is equal to or less than a predetermined value. The impact light emitting point detection device described. 2. The impact light emission point detection device according to claim 1, wherein the impact light emission start determination circuit determines whether or not a bullet has landed and started light emission based on the following equation (1).

3. The impact light emitting point detecting device according to claim 2, wherein the muzzle flame extinction circuit determines whether or not the muzzle flame has disappeared based on the following equation (2).

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