Measuring device

Abstract

To provide a measuring device capable of precisely measuring a track and a height of a moving object by a simple method.SOLUTION: A measuring device includes: an acquisition section for acquiring an event signal from an imaging device having an event base vision sensor; a first image generation section for generating a first image on the basis of an event signal acquired during a first period; a determination section for determining whether a height of a moving object is less than a predetermined height on the basis of the first image generated for each first period; a second image generation section for generating a second image including a track region showing the track of a moving object on the basis of an event signal acquired during a second period between first timing after lapse of first time from a point of time when the height of a moving object becomes less than a predetermined height and second timing after lapse of second time from the point of time; and a calculation section for calculating a height of flip-back of a moving object on the basis of the second image. The second period is longer than the first period.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present disclosure relates to a measuring device.

Background Art

[0002] Conventionally, a method of extracting the movement trajectory of an object (e.g., a ball) using a camera has been known. For example, Japanese Patent Application Laid-Open No. 2001-273500 (Patent Document 1) discloses a moving object measuring device. The moving object measuring device includes a TV camera and a world coordinate trajectory extraction set that extracts a world coordinate trajectory, which is a coordinate system based on the space where the moving object exists. The world coordinate trajectory extraction set detects a moving object from an image captured by the camera and converts the trajectory of the moving object from the coordinate system based on the camera to world coordinates and outputs it.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, the projection trajectory of the movement trajectory between the world coordinates at the position where the ball touches the ground onto the ground is regarded as a straight line or a predetermined curve to determine the two-dimensional movement trajectory of the ball, and the height of the ball is calculated from the two-dimensional movement trajectory and the movement trajectory on the image. However, in the method of calculating the height of the ball using an ordinary TV camera, there is a problem that the amount of information of the background other than the ball is large, and the algorithm becomes complicated in order to accurately calculate the movement trajectory (and height) of the ball.

[0005] An object of one aspect of the present disclosure is to provide a measuring device capable of accurately measuring the trajectory and height of a moving object in a simple manner.

Means for Solving the Problems

[0006] A measuring device according to one embodiment includes: an acquisition unit that acquires an event signal including the coordinates and time of the pixel where the brightness change occurred from an imaging device having an event-based vision sensor that detects brightness changes of a moving object falling onto a receiving member; a first image generation unit that generates a first image based on the event signal acquired in a first period; a determination unit that determines whether the height of the moving object has fallen below a predetermined height based on the first image generated for each first period; a second image generation unit that generates a second image including a trajectory region showing the trajectory of the moving object based on an event signal acquired in a second period between a first timing, which is a first time interval after the point in time when the height of the moving object falls below the predetermined height, and a second timing, which is a second time interval after the point in time; and a calculation unit that calculates the bounce height of the moving object when it is dropped onto the receiving member based on the second image. The second period is longer than the first period. [Effects of the Invention]

[0007] According to this disclosure, the trajectory and height of a moving object can be measured accurately using a simple method. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram illustrating the overall configuration of the measurement system. [Figure 2] This is a block diagram showing the hardware configuration of the measuring device. [Figure 3] This is a flowchart illustrating an example of how the measuring device operates. [Figure 4] This figure shows an example of a frame image. [Figure 5] This is a diagram illustrating an example of a fall detection processing method. [Figure 6] This is a diagram illustrating the method for measuring the bounce height of a ball. [Figure 7] This figure shows an example of a frame image near the highest point of a ball's bounce. [Figure 8] This is a diagram illustrating variations in the measurement method. [Figure 9] This diagram illustrates the method for measuring the amount of lateral displacement before and after a ball bounces back. [Figure 10] This is a block diagram showing an example of the functional configuration of a measuring device. [Modes for carrying out the invention]

[0009] This embodiment will be described below with reference to the drawings. In the following description, identical parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

[0010] <Overall Structure> Figure 1 is a diagram illustrating the overall configuration of the measurement system 1000. Referring to Figure 1, the measurement system 1000 is a system for measuring the maximum height (i.e., bounce height) of the ball 30 after it has bounced off the receiving member 40 by free-dropping a ball 30 from a predetermined height (for example, a position 4 m above the receiving member 40). This measurement is performed to confirm the rebound performance of the ball 30. The ball 30 is, for example, a baseball. The receiving member 40 is, for example, marble, but may be made of other materials.

[0011] Conventionally, the bounce height of the ball 30 that bounced off the receiving member 40 was measured visually. However, this measurement method is subject to large variations due to the skill level and fatigue of the person taking the measurement, requiring a dedicated person for measurement.

[0012] In addition, a method of imaging the ball 30 using a camera that uses an image sensor such as a generally widely used CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor), and measuring the bounce height of the ball 30 from the obtained captured image is also conceivable. However, according to this method, since the captured image contains a lot of information such as the background other than the ball 30, there is a problem that the processing for accurately obtaining the trajectory of the ball 30 (for example, the processing for removing background information) becomes complicated.

[0013] Therefore, the measurement system 1000 according to the present embodiment is configured to measure the bounce height of the ball 30 using the imaging device 20 equipped with an event-driven (base) vision sensor. Specifically, the measurement system 1000 includes a measurement device 10 and an imaging device 20.

[0014] The imaging device 20 is an imaging device having an event-based vision sensor (hereinafter, also referred to as an "event sensor") that detects the luminance change of a moving object. The event sensor detects the change in luminance for each pixel asynchronously as an event, and can operate at low power and high speed compared to image sensors such as CCDs and CMOSs. Since the luminance change of a pixel occurs when the subject moves, the image obtained by the event sensor contains only the moving subject and does not contain background information that does not move. More specifically, when the luminance change of the light captured by a pixel exceeds a set threshold value, the event sensor detects it as an event and outputs an event signal including the coordinates, time, and polarity of the pixel where the event occurred.

[0015] Typically, the imaging device 20 is fixed in advance so that the position of the bounce height of the ball 30 (that is, the maximum height of the ball 30 after bouncing off the receiving member 40) is included in the imaging range 25 of the imaging device 20.

[0016] The measuring device 10 is composed of a laptop PC (Personal Computer). However, the measuring device 10 can be realized as any device regardless of its type. For example, the measuring device 10 may be a smartphone, a tablet terminal, a desktop PC, etc. Typically, the measuring device 10 is connected to the imaging device 20 by a wired communication method, but it may also be configured to be connected to the imaging device 20 by a wireless communication method.

[0017] The measuring device 10 is configured to be communicable with the imaging device 20 and receives an event signal output from the imaging device 20. The measuring device 10 generates an image based on the event signal and measures the bounce height of the ball 30 from the trajectory of the ball 30 included in the image. The measuring device 10 displays the measurement result on a display.

[0018] <Hardware Configuration> FIG. 2 is a block diagram showing the hardware configuration of the measuring device 10. Referring to FIG. 2, the measuring device 10 includes, as main components, a processor 102, a memory 104, an input device 106, a display 108, and a communication interface (I / F) 110. These components are connected to each other by a bus.

[0019] The processor 102 controls the operations of each part of the measuring device 10 by reading and executing a program stored in the memory 104. The processor 102 is typically an arithmetic processing unit such as a CPU (Central Processing Unit) or an MPU (Multi Processing Unit). More specifically, the processor 102 realizes the processing of the measuring device 10 described later by executing the program.

[0020] ` The memory 104 is realized by a RAM (Random Access Memory), a ROM (Read-Only Memory), a hard disk, etc. The memory 104 stores a program executed by the processor 102 or data used by the processor 102.

[0021] The input device 106 receives operational input for the measuring device 10. The input device 106 can be implemented as, for example, a keyboard, buttons, or a mouse. Alternatively, the input device 106 may be implemented as a touch panel. The display 108 displays images, text, and other information on the display screen based on signals from the processor 102.

[0022] The communication interface 110 communicates signals with the imaging device 20. The communication interface 110 communicates with the imaging device 20 using a wired communication method such as USB (Universal Serial Bus) or a wireless communication method such as Bluetooth (registered trademark) or Wi-Fi (Local Area Network).

[0023] <Example of operation> Figure 3 is a flowchart illustrating an example of the operation of the measuring device 10. Typically, each step shown in Figure 3 is performed by the processor 102.

[0024] The measuring device 10 acquires (receives) each event signal output from the imaging device 20 (step S10). The event signal includes at least the position and time of the pixel where the brightness change occurred.

[0025] The measuring device 10 generates a frame image based on the event signal corresponding to the period Da (e.g., 0.02 seconds) (step S12). Specifically, the measuring device 10 generates one frame image for each period Da by combining the event signals of each pixel. For example, a frame image is generated in which pixels with a change in brightness are represented as "1" and pixels without a change in brightness are represented as "0".

[0026] Figure 4 shows an example of a frame image. Referring to Figure 4, the frame image 72 shows a white area representing the falling ball 30. Specifically, the frame image 72 is generated by synthesizing event signals acquired during a period Da1 (e.g., 0.02 seconds). Typically, the measuring device 10 recognizes the largest white area in the frame image 72 as the area representing the ball 30.

[0027] Furthermore, the frame image 72 shown in Figure 3 has undergone known image processing to remove noise. For example, image processing includes filtering, grayscale conversion, binarization, and dilation.

[0028] In frame image 72, for example, the upper left pixel is defined as the origin (0,0), the horizontal direction is defined as the X-axis direction, and the vertical direction is defined as the Y-axis direction. In this case, the coordinates of the rightmost pixel on the X-axis in frame image 72 are (Xn,0), the coordinates of the lowermost pixel on the Y-axis in frame image 72 are (0,Yn), and the coordinates of the lower rightmost pixel in frame image 72 are (Xn,Yn). Note that the X-axis direction indicates the horizontal direction, and the Y-axis direction indicates the vertical direction. More specifically, the negative direction of the Y-axis indicates the vertically upward direction, and the positive direction of the Y-axis indicates the vertically downward direction. This method of defining axes and coordinates is the same for each of the following images.

[0029] Referring again to Figure 3, the measuring device 10 performs a fall determination process to determine whether the ball 30 has fallen to a height below a predetermined height based on the frame images generated for each period Da (step S14).

[0030] Figure 5 is a diagram illustrating an example of a fall detection processing method. Referring to Figure 5, frame images 72, 74, and 76 show white areas indicating the falling ball 30. Specifically, frame image 72 is generated by combining each event signal acquired in period Da1. Similarly, frame image 74 is generated by combining each event signal acquired in period Da2, which is after period Da1, and frame image 76 is generated by combining each event signal acquired in period Da3, which is after period Da2. Periods Da1 to Da3 are all the same duration (e.g., 0.02 seconds).

[0031] The measuring device 10 determines that the height of the ball 30 has fallen below a predetermined height when the ball 30 reaches below the line L1. For example, the measuring device 10 determines that the height of the ball 30 has fallen below a predetermined height when the Y coordinates of all (or some) pixels in the white area representing the ball 30 become greater than the Y coordinate of the line L1. Hereafter, the point in time when the measuring device 10 determines that the height of the ball 30 has fallen below a predetermined height will also be referred to as the "fall determination point." Note that the position of the line L1 shown in Figure 5 is just an example, and it may be set at other positions.

[0032] Referring again to Figure 3, the measuring device 10 generates an image for measuring the bounce height of the ball 30 (hereinafter also referred to as the "measurement image") based on the event signal corresponding to the period Db after the fall detection point (step S16).

[0033] Period Db is set to the period between timing t1, which is time T1 after the fall detection point, and timing t2, which is time T2 after the fall detection point (provided T2 > T1). Period Db is set to include the period from when the ball 30 bounces off the receiving member 40 and rises until it falls.

[0034] For example, time T1 is 0.4 seconds and time T2 is 1.0 seconds. In this case, the period Db is 0.6 seconds. Times T1 and T2 are set by utilizing the fact that the time it takes for the ball 30, which has free-fallen and bounced off the receiving member 40, to reach its highest point falls within a certain time. Thus, it can be seen that the period Db (e.g., 0.6 seconds) is a very long period compared to the period Da (e.g., 0.02 seconds) mentioned above.

[0035] Next, the measuring device 10 measures the bounce height of the ball 30 using the measurement image (step S18).

[0036] Figure 6 is a diagram illustrating the method for measuring the bounce height of a ball. Referring to Figure 6, the measuring device 10 generates a measurement image 80 by synthesizing the event signals of each pixel acquired during period Db. Since the measurement image 80 is an image that accumulates images based on each event signal of each pixel acquired during period Db, it includes a trajectory region that shows the trajectory of the ball 30.

[0037] Typically, the measuring device 10 recognizes the largest white area in the measurement image 80 (i.e., the parabolic region of the measurement image 80) as the trajectory region of the ball 30. Note that, similar to the frame image, known image processing techniques for noise reduction are applied to the measurement image 80.

[0038] The measuring device 10 identifies the smallest Y coordinate among the Y coordinates of each pixel included in the trajectory region (for example, the Y coordinate of the line L2 in Figure 6), and converts the identified Y coordinate into actual height information (for example, the height from the receiving member 40).

[0039] We will now explain in more detail why, when measuring the bounce height, we use a measurement image 80 generated based on an event signal corresponding to period Db, rather than a frame image generated based on an event signal corresponding to period Da (e.g., 0.02 seconds).

[0040] Figure 7 shows an example of a frame image near the highest point of the ball's bounce. Referring to Figure 7, frame image 78 is an image generated based on each event signal acquired during period Da near the highest point of the ball's bounce.

[0041] From frame image 78, it can be seen that there is almost no white area indicating ball 30. This is because, near the highest point of the bounce, ball 30 is almost stationary, so no change in pixel brightness occurs, and the event sensor does not detect an "event". Therefore, as described above, by setting the period Db to include the period from when the bounced ball 30 rises, reaches its highest point, and begins to fall, it is possible to obtain a single measurement image 80 in which the trajectory of ball 30, as shown in Figure 6, can be clearly seen. This allows for accurate measurement of the bounce height of ball 30.

[0042] Referring again to Figure 3, the measuring device 10 outputs the measurement result of the bounce height of the ball 30 (step S20). Typically, the measuring device 10 displays the measurement result on the display 108. The measuring device 10 may also transmit the measurement result to another device, or it may output the measurement result as audio via a speaker (not shown).

[0043] The above describes a method for calculating the bounce height of ball 30 based on the minimum Y coordinate in the orbital region. However, according to this method, for example, if a white area indicating noise is superimposed on the edge of the orbital region, and the minimum Y coordinate can be obtained in that white area, the bounce height of ball 30 will be calculated based on that minimum Y coordinate. In other words, since the bounce height of ball 30 is calculated based on noise, measurement errors will occur.

[0044] Therefore, in the modified measurement method, in order to avoid measurement errors due to noise as described above, we will explain a method of calculating the bounce height of the ball 30 based on the Y coordinate at the center of the orbital region.

[0045] Figure 8 illustrates variations of the measurement method. Figure 8(a) shows a measurement image according to variation (1). Figure 8(b) shows a measurement image according to variation (2).

[0046] Referring to Figure 8(a), the measurement image 91 is generated based on the event signal corresponding to period Db. The measuring device 10 recognizes the largest white area in the measurement image 91 (i.e., the parabolic region in the measurement image 91) as the trajectory region of the ball 30. The measuring device 10 identifies the center of the trajectory region in the horizontal direction (i.e., the X-axis direction) and measures the bounce height of the ball 30 based on the vertical coordinate (i.e., the Y-coordinate) of that center.

[0047] The method for identifying the central part will now be explained. The measuring device 10 acquires the coordinates (i.e., X coordinates) of pixels at one end (e.g., the left end) and the other end (e.g., the right end) of the orbital region in the horizontal direction. In the measurement image 91, it is shown that the X coordinate of the leftmost pixel is X1 (hereinafter also referred to as "left end coordinate X1"), and the X coordinate of the rightmost pixel is X2 (hereinafter also referred to as "right end coordinate X2"). Based on the left end coordinate X1 and the right end coordinate X2, the measuring device 10 calculates the center coordinate X3 in the X-axis direction of the orbital region. "X3 = (X1 + X2) / 2".

[0048] The measuring device 10 identifies the central region as the area where the horizontal distance from the central coordinate X3 is within a predetermined range. For example, in the orbital region, the measuring device 10 identifies the central region as the area where the X coordinate ranges from "X3-k" to "X3+k" (i.e., (X3-k)≦X≦(X3+k)). In this case, (2k+1) pixels, including the pixel of the central coordinate X3, correspond to the central region. k is, for example, 10.

[0049] The measuring device 10 measures the bounce height of the ball 30 based on the smallest Y coordinate among the Y coordinates of each pixel included in the central area identified as described above.

[0050] Furthermore, as shown in Figure 8(b), the following processing may be added so that the center coordinate X3 becomes the center position of the parabola representing the orbital region.

[0051] The measuring device 10 generates a measuring image 93 by cropping and deleting pixels containing Y coordinates greater than or equal to a predetermined value in the measuring image 91. The predetermined value is determined appropriately based on empirical rules or the like. The measuring image 93 contains only the trajectory region near the highest point of the parabola. Therefore, if the center coordinate X3 in the X-axis direction of the trajectory region is calculated in the same way as in Figure 8(a), the center coordinate X3 will be approximately the center of the parabola. The measuring device 10 then identifies the portion within a predetermined range of horizontal distance from the center coordinate X3 as the central region and measures the bounce height of the ball 30 based on the Y coordinate at the central region.

[0052] According to the above configuration, the bounce height of the ball 30 can be calculated only in the central part of the orbital region, thereby preventing measurement errors due to noise.

[0053] <Method for measuring lateral displacement> Figure 9 is a diagram illustrating the measurement method for the amount of lateral displacement of the ball 30 before and after it bounces. Referring to Figure 9, the frame image 95 is generated by synthesizing event signals acquired during a certain period Da of free fall before the ball 30 bounces off the receiving member 40. The measurement image 97 is generated by synthesizing event signals acquired during period Db.

[0054] The measuring device 10 calculates the horizontal center coordinate Xa of the white region representing the falling ball 30 in the frame image 95. The measuring device 10 calculates the horizontal center coordinate Xb of the white region representing the trajectory region of the ball 30 in the measurement image 97. The center coordinate Xb corresponds to the center coordinate X3 explained in Figure 8.

[0055] The measuring device 10 measures the amount of lateral displacement E, which indicates how much the ball 30 has shifted horizontally before and after it bounces off the receiving member 40, based on the central coordinates Xa and Xb. Specifically, the amount of lateral displacement E is calculated as the distance between the central coordinates Xa and Xb (i.e., |Xa-Xb|).

[0056] If the lateral displacement E is greater than or equal to a threshold, it is considered that the bounce height of the ball 30 has not been measured properly. Therefore, the measuring device 10 processes the measurement result of the bounce height of the ball 30 as an error. For example, the measuring device 10 assigns an error flag to the measurement result. The lateral displacement E is also used as an indicator for quality checking of the ball 30.

[0057] <Functional Configuration> Figure 10 is a block diagram showing an example of the functional configuration of the measuring device 10. Referring to Figure 10, the measuring device 10 includes an acquisition unit 202, a first image generation unit 204, a determination unit 206, a second image generation unit 208, a calculation unit 210, and an output unit 212. Typically, these functional configurations are implemented by the processor 102 of the measuring device 10. Note that some or all of these functional configurations may be implemented in hardware.

[0058] The acquisition unit 202 acquires event signals from the imaging device 20 which has an event sensor. The first image generation unit 204 generates frame images (for example, frame images 72, 74, 76, etc.) based on the event signals acquired in period Da. Specifically, for each period Da, the first image generation unit 204 generates one frame image by combining the event signals acquired in that period Da.

[0059] The determination unit 206 determines whether the height of the ball 30 has fallen below a predetermined height based on the frame images generated for each period Da. The determination unit 206 then executes the fall detection process described in Figure 5.

[0060] The second image generation unit 208 generates a measurement image (e.g., measurement image 80) including the trajectory region of the ball 30 based on event signals acquired during the period Db between timing t1, which is time T1 elapsed from the point in time when the height of the ball 30 falls below a predetermined height (e.g., the time when the fall is determined), and timing t2, which is time T2 elapsed from that point in time.

[0061] The calculation unit 210 calculates the bounce height of the ball 30 when it is dropped freely onto the receiving member 40, based on the measurement image. In a certain scenario, the calculation unit 210 identifies the center of the trajectory region in the horizontal direction in the measurement image and calculates the bounce height of the ball 30 based on the vertical coordinate (e.g., Y coordinate) of that center. Specifically, the calculation unit 210 obtains the coordinates of one end and the other end of the trajectory region in the horizontal direction and calculates the center coordinate X3 of the trajectory region in the horizontal direction based on the coordinate of one end (e.g., left end coordinate X1) and the coordinate of the other end (e.g., right end coordinate X2). The calculation unit 210 identifies the portion within a predetermined range of horizontal distance from the center coordinate X3 as the center.

[0062] In other phases, the calculation unit 210 calculates the horizontal center coordinates (e.g., center coordinate Xa) of the region showing the falling ball 30 based on the frame image. Based on the center coordinate Xa and the horizontal center coordinates (e.g., center coordinate Xb) of the trajectory region based on the measurement image, the calculation unit 210 calculates the amount of lateral displacement of the ball 30 before and after the bounce.

[0063] <Advantages> According to this embodiment, by utilizing an event sensor, the bounce height of the ball 30 can be measured accurately without using a complex algorithm. Compared to when a person measures visually, measurement variability can be reduced. In addition, since the bounce height of the ball 30 is measured automatically, the measurement time can also be shortened.

[0064] <Other embodiments> (1) In the embodiment described above, the case in which the moving object, the ball 30, is a baseball is described as a hardball, but the ball 30 may be a softball, softball, tennis ball, basketball, golf ball, etc. Alternatively, the ball 30 may be a metal ball, and the receiving member 40 may be a cushioning material, etc. In this case, the characteristics of the receiving member 40 can be evaluated by calculating the bounce height of the ball 30 using the measuring device 10.

[0065] (2) It is also possible to provide a program that makes the computer function and performs the control described in the above-described embodiment. Such a program can be recorded on a non-temporary computer-readable recording medium such as a flexible disk, CD-ROM (Compact Disc Read Only Memory), ROM, RAM, and memory card attached to the computer and provided as a program product. Alternatively, the program can be recorded on a recording medium such as a hard disk built into the computer and provided. Furthermore, the program can be provided by downloading it over a network.

[0066] (3) The configurations described above as embodiments are examples of the configuration of the present invention, and can be combined with other known technologies, and can be modified, such as by omitting parts, without departing from the spirit of the present invention.

[0067] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0068] 10 Measuring device, 20 Imaging device, 25 Imaging range, 30 Ball, 40 Receiving member, 72, 74, 76, 78, 95 Frame images, 80, 91, 93, 97 Measurement images, 102 Processor, 104 Memory, 106 Input device, 108 Display, 110 Communication interface, 202 Acquisition unit, 204 First image generation unit, 206 Judgment unit, 208 Second image generation unit, 210 Calculation unit, 212 Output unit, 1000 Measurement system.

Claims

1. An acquisition unit acquires an event signal, including the coordinates and time of the pixel where the brightness change occurred, from an imaging device having an event-based vision sensor that detects brightness changes of a moving object falling onto a receiving member. A first image generation unit generates a first image based on the event signal acquired during the first period, A determination unit that determines whether the height of the moving object has fallen below a predetermined height based on the first image generated for each of the first periods, A second image generation unit generates a second image including a trajectory region showing the trajectory of the moving object based on the event signal acquired during a second period between a first timing, which occurs a first time interval after the time the height of the moving object falls below a predetermined height, and a second timing, which occurs a second time interval after the time the event signal is acquired. The system includes a calculation unit that calculates the bounce height of the moving object when the moving object is dropped onto the receiving member based on the second image, The second period is longer than the first period, and the measuring device is longer.

2. The measuring device according to claim 1, wherein the second period includes the period from when the moving object bounced off the receiving member upwards until it falls.

3. The calculation unit described above, Identify the central part of the trajectory region in the horizontal direction, The measuring device according to claim 1 or 2, which calculates the bounce height of the moving object based on the vertical coordinates in the central part.

4. The calculation unit described above, Obtain the coordinates of one end and the other end of the trajectory region in the horizontal direction. Based on the coordinates of one end and the coordinates of the other end, the first center coordinate of the trajectory region in the horizontal direction is calculated. The measuring device according to claim 3, wherein the portion within a predetermined range of horizontal distance from the first central coordinate is identified as the central portion.

5. The calculation unit described above, Based on the first image, the second horizontal center coordinate of the region showing the falling moving object is calculated, The measuring device according to claim 4, which calculates the amount of lateral displacement of the moving object before and after the bounce based on the first and second center coordinates.

Images