Vibration visualization device, vibration visualization method, and vibration visualization program

Abstract

To provide a vibration visualization device, a vibration visualization method, and a vibration visualization program that can confirm a vibration state of a target object in real time.SOLUTION: A vibration visualization device 1 includes a total point displacement calculation unit 23, Fourier coefficient moving average calculation unit 24, and an amplitude-enhanced image generation unit 26. The total point displacement calculation unit 23 sequentially calculates a total point displacement for each frame obtained after a reference frame, which is the displacement of all points in the field of view of the moving image obtained by photographing a target object using the reference frame of the moving image as a reference. The Fourier coefficient moving average calculation unit 24 calculates Fourier coefficients at an extraction frequency, which is a frequency of a vibration component to be extracted for each of the total points from the latest total point displacement calculated and calculates a moving average of the Fourier coefficients previously calculated for each of the total points. The amplitude-enhanced image generation unit 26 calculates a displacement value at the current time for each of the total points using the calculated Fourier coefficients and performs motion compensation on the reference frame using a value obtained by expanding the displacement value at a predetermined expansion rate to generate an amplitude-enhanced image.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vibration visualization device, a vibration visualization method, and a vibration visualization program. [Background technology]

[0002] There is a known method for visualizing vibrations by emphasizing them based on moving images captured by a photographing device such as a camera (see, for example, Non-Patent Document 1 below). In this method, optical flow (see, for example, Non-Patent Document 2 below) is applied to the moving images to obtain the time series displacements of all points in the field of view, and then a discrete Fourier transform and an inverse transform are applied to the time series displacements of each point. Furthermore, a motion-compensated image is generated by transferring the pixel values ​​of each point in the reference time image to the coordinates of the destination at each time. At this time, an image in which the amplitude is emphasized at an arbitrary magnification is generated by multiplying (for example, by 100 times) the motion vector and using it. In this way, slight movements that are difficult to see with the naked eye are enlarged and displayed, making it easy to grasp the vibration shape.

[0003] Since changes in the strength of a structure are believed to appear in the shape of its natural vibration, it is possible to read signs of deterioration by understanding the shape of the vibration. For example, if the vibration posture of a utility pole can be visualized in real time (instantaneously) using the above-mentioned method when patrolling the utility pole, it is expected that information useful for evaluating the strength of the utility pole can be easily collected. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Takada Jun, "Visualization of vibration behavior of utility poles using optical vibration measurement technology," IEEJ Division Conference, 2022, C, pp. 982-986 [Non-Patent Document 2] Thomas Brox, et al. “High Accuracy Optical Flow Estimation Based on a Theory for Warping”, ECCV. 2004, LNCS 3024, pp.25-36 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional method described above requires a long processing time because it is necessary to perform discrete Fourier transform and inverse transform for all points in the field of view. For example, in order to perform Fourier transform and inverse transform for all pixels of a 1024-time moving image with 1 million pixels (1000 x 1000 pixels), the Fourier transform and inverse transform must be performed 1 million times for the signal of 1024 samples. Therefore, when trying to check the visualization results of vibration on site, there is a problem that it is difficult to check the vibration state of the object to be visualized in real time while photographing the object.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a vibration visualization device, a vibration visualization method, and a vibration visualization program that can check the vibration state of an object in real time. [Means for solving the problem]

[0007] In order to solve the above problems, a vibration visualization device according to a first aspect of the present invention is a vibration visualization device (1) that performs image processing on a moving image obtained by photographing an object, to visualize a vibration state of the object, and includes an all-point displacement calculation unit (23) that sequentially calculates all-point displacements, which are displacements at all points within a field of view of the moving image, for each frame obtained after a reference frame of the moving image, using the reference frame as a reference, a Fourier coefficient moving average calculation unit (24) that calculates, for each of the all-point displacements, a Fourier coefficient at an extraction frequency, which is a frequency of a vibration component to be extracted, from the latest all-point displacements calculated by the all-point displacement calculation unit, and calculates a moving average with the previously calculated Fourier coefficient for each of the all points, and an amplitude-emphasized image generation unit (26) that uses the Fourier coefficients calculated by the Fourier coefficient moving average calculation unit to calculate a displacement value at a current time for each of the points, and performs motion compensation for the reference frame using values ​​obtained by enlarging the displacement values ​​at a predetermined magnification rate, to generate an amplitude-emphasized image.

[0008] The vibration visualization device according to the second aspect of the present invention, in the vibration visualization device according to the first aspect of the present invention, further comprises a maximum amplitude calculation unit (25) which calculates a maximum amplitude value from the Fourier coefficients of all the points calculated by the Fourier coefficient moving average calculation unit, and the amplitude-enhanced image generation unit uses, as the predetermined magnification ratio, a value obtained by dividing a preset amplitude magnification ratio by the maximum amplitude value calculated by the maximum amplitude calculation unit.

[0009] A vibration visualization device according to a third aspect of the present invention is a vibration visualization device according to the first or second aspect of the present invention, wherein the amplitude-emphasized image generation unit generates, as the amplitude-emphasized image, a moving image in which the extracted vibration component of the object is displayed as vibrating at a specified display frequency.

[0010] The vibration visualization device according to a fourth aspect of the present invention is the vibration visualization device according to the third aspect of the present invention, further comprising a frequency setting section (21) that sets the extraction frequency.

[0011] A vibration visualizing device according to a fifth aspect of the present invention is the vibration visualizing device according to the fourth aspect of the present invention, wherein the frequency setting section sets the display frequency.

[0012] A vibration visualization method according to one aspect of the present invention is a vibration visualization method that performs image processing on a moving image obtained by photographing an object to visualize the vibration state of the object, and comprises the steps of: determining all-point displacements, which are the displacements at all points within the field of view of the moving image, for each frame obtained after a reference frame of the moving image, in sequence for each frame obtained after the reference frame (S13); determining, from the latest determined all-point displacements, a Fourier coefficient at an extraction frequency, which is the frequency of the vibration component to be extracted, for each of the all points; calculating a moving average with the previously determined Fourier coefficient for each of the all points (S14); determining a displacement value at the current time for each of the all points using the calculated Fourier coefficient; and magnifying the displacement value at a predetermined magnification rate using the value to perform motion compensation for the reference frame to generate an amplitude-emphasized image (S16).

[0013] A vibration visualization program according to one embodiment of the present invention causes a computer to execute the following steps: determine all-point displacements, which are the displacements at all points within the field of view of a moving image obtained by photographing an object, for each frame obtained after a reference frame of the moving image (S13); determine, from the latest determined all-point displacements, a Fourier coefficient at an extraction frequency, which is the frequency of the vibration component to be extracted, for each of the all points; calculate a moving average with the previously determined Fourier coefficient for each of the all points (S14); determine a displacement value at the current time for each of the all points using the calculated Fourier coefficients; and perform motion compensation for the reference frame using values ​​obtained by magnifying the displacement values ​​at a predetermined magnification rate to generate an amplitude-emphasized image (S16). Effect of the Invention

[0014] According to the present invention, it is possible to confirm the vibration state of an object in real time. [Brief description of the drawings]

[0015] [Figure 1] 1 is a block diagram showing a configuration of a main part of a vibration visualization device according to a first embodiment of the present invention. FIG. [Diagram 2] 1 is a flowchart illustrating an example of a vibration visualization method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration visualization device, a vibration visualization method, and a vibration visualization program according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0017] <Vibration visualization device> Fig. 1 is a block diagram showing the main components of a vibration visualization device according to a first embodiment of the present invention. As shown in Fig. 1, the vibration visualization device 1 according to this embodiment includes an image input unit 10, a processing unit 20, a storage unit 30, and an image output unit 40. Such a vibration visualization device 1 performs image processing on a moving image obtained by photographing an object, and visualizes the vibration state of the object. Note that the object may be any object, but an example of the object is a structure such as a utility pole whose vibration is difficult to see with the naked eye and for which it is necessary to determine the change in intensity.

[0018] The image input unit 10 inputs a moving image obtained by photographing an object. The image input unit 10 may include, for example, a connection interface to which a photographing device such as a camera is connected. The moving image input to the image input unit 10 has, for example, a pixel count of about 1 million pixels (1000×1000 pixels) and a frame rate of about 100 fps (Frames Per Second). Note that the pixel count and frame rate of the moving image are not limited to the above example and may be arbitrary.

[0019] The processing unit 20 includes a frequency setting unit 21, a memory control unit 22, a all-point displacement calculation unit 23, a Fourier coefficient moving average calculation unit 24, a maximum amplitude calculation unit 25, and an amplitude-emphasized image generation unit 26. The processing unit 20 performs image processing on the moving image input to the image input unit 10 to generate an amplitude-emphasized image in which the vibration amplitude of the object is emphasized, and outputs the generated amplitude-emphasized image to the image output unit 40.

[0020] The frequency setting unit 21 sets an extraction frequency, which is the frequency of the vibration component to be extracted, based on a user's instruction input from an input device (not shown), and stores the frequency in a frequency storage unit 31 (details of which will be described later) of the storage unit 30. Since an object may vibrate at various frequencies depending on its structure, shape, material, etc., the vibration of the object may contain vibration components having various frequencies. The extraction frequency is set in order to extract a vibration component having a frequency of interest from among the vibration components having various frequencies contained in the vibration of the object.

[0021] In addition, the frequency setting unit 21 sets a display frequency, which is a frequency at which the extracted vibration component is displayed, based on a user's instruction input from an input device (not shown), and stores the display frequency in the frequency storage unit 31 of the storage unit 30. When the extracted vibration component is a high frequency (e.g., 30 Hz), the vibration shape of the amplitude-enhanced image of the vibration component displayed in real time changes too quickly, making it difficult to grasp the vibration shape. To avoid this, if the amplitude-enhanced image is displayed in slow motion (e.g., at 1 / 10 speed), when a low-frequency vibration component is extracted, the vibration shape changes too slowly, making it difficult to grasp the vibration shape. The display frequency is set to display the amplitude-enhanced image of the extracted vibration component at an appropriate frequency according to the frequency of the extracted vibration component.

[0022] The storage control unit 22 sequentially stores the moving images input to the image input unit 10 in the storage unit 30. Specifically, the storage control unit 22 stores the first frame of the moving image input to the image input unit 10 in a reference image storage unit 32 (described in detail below) of the storage unit 30, and sequentially stores the next and subsequent frames in a latest image storage unit 33 (described in detail below). Furthermore, the storage control unit 22 increments the frame number stored in a frame number storage unit 34 (described in detail below) every time it stores a frame of the moving image in the storage unit 30.

[0023] The all-point displacement calculation unit 23 determines all-point displacements, which are displacements at all points within the field of view of the moving image input to the image input unit 10, for the next and subsequent frames, with the first frame (reference frame) of the moving image as a reference. Specifically, the all-point displacement calculation unit 23 reads out the image (reference frame) stored in the reference image storage unit 32 of the storage unit 30 and the image stored in the latest image storage unit 33 every time a frame (image) is stored in the latest image storage unit 33 of the storage unit 30. Then, the all-point displacement calculation unit 23 determines the displacements (all-point displacements) for all pixels of the image read out from the latest image storage unit 33, with the image read out from the reference image storage unit 32 as a reference. The all-point displacement calculation unit 23 stores the determined all-point displacements in the all-point displacement storage unit 35 of the storage unit 30 (details of which will be described later).

[0024] The Fourier coefficient moving average calculation unit 24 calculates the Fourier coefficient at the extraction frequency stored in the frequency storage unit 31 for each of the above-mentioned all points from the latest all-point displacement calculated by the all-point displacement calculation unit 23. Then, the Fourier coefficient moving average calculation unit 24 calculates the moving average of the newly calculated Fourier coefficient and the previously calculated Fourier coefficient for each of the points. The moving average may be any moving average such as a simple moving average, a weighted moving average, or an exponential moving average. The Fourier coefficient moving average calculation unit 24 stores the calculated Fourier coefficients and moving averages for all points in a Fourier coefficient storage unit 36 ​​(details of which will be described later).

[0025] For example, consider a case where the Fourier coefficient moving average calculation unit 24 performs an exponential moving average as the moving average. In this case, the Fourier coefficient moving average calculation unit 24 calculates the Fourier coefficient U t (x, y) is calculated using the following equation (1), and the Fourier coefficient of the vertical displacement V t (x, y) is calculated using the following equation (2).

[0026]

number

number

[0027] In the above formulas (1) and (2), u t (x,y) is the horizontal displacement of the (x,y) coordinate in the t-th frame, and v t (x,y) is the vertical displacement of the (x,y) coordinate in the t-th frame. Also, f cap is the frame rate of the video, and f tgt is the extraction frequency, and α is the weighting coefficient of the moving average (e.g., 0.02, etc.).

[0028] The Fourier coefficient moving average calculation unit 24 reads out the image of the t-th frame from the latest image storage unit 33 and calculates the extracted frequency f tgt from the frequency storage unit 31. The Fourier coefficient moving average calculation unit 24 also reads out the Fourier coefficient U t (x,y) and the Fourier coefficients of the vertical displacement V t-1 (x, y) is read from the Fourier coefficient storage unit 36.

[0029] The maximum amplitude calculation unit 25 calculates the maximum amplitude from each Fourier coefficient of all points calculated by the Fourier coefficient moving average calculation unit 24, and stores the calculated maximum amplitude in the maximum amplitude storage unit 37 (details will be described later) of the storage unit 30. The maximum amplitude calculation unit 25 is provided to automatically obtain an optimal degree of emphasis of the amplitude. The amplitude of the vibration varies in various ways depending on the extraction frequency. For this reason, the emphasis ratio at which the vibration shape is easily recognized may be 100 times at one frequency and 1000 times at another frequency. Therefore, every time the frequency of interest is changed, it is troublesome to search for an appropriate emphasis ratio. By providing the maximum amplitude calculation unit 25, such troublesome work can be eliminated.

[0030] The maximum amplitude calculation unit 25 calculates the maximum amplitude value R t Ask for The maximum amplitude R t can also be said to be a normalization parameter for normalizing the amplitude of the (x, y) coordinates in the t-th frame.

[0031]

number

[0032] The amplitude-emphasised image generating unit 26 uses the Fourier coefficients calculated by the Fourier coefficient moving average calculating unit 24 to determine the displacement value at the current time for each of all points. Then, the amplitude-emphasised image generating unit 26 performs motion compensation on the image (reference frame) stored in the reference image storage unit 32 of the storage unit 30 using values ​​obtained by enlarging the determined displacement values ​​at a predetermined enlargement rate, thereby generating an amplitude-emphasised image. Here, the amplitude-emphasised image generating unit 26 multiplies the amplitude expansion rate stored in the amplitude expansion rate storage unit 38 (details of which will be described later) of the storage unit 30 by the maximum amplitude R determined by the maximum amplitude calculating unit 25. t The value obtained by dividing by is used as the above-mentioned predetermined magnification ratio. For example, the amplitude-weighted image generating unit 26 calculates the horizontal displacement of the (x, y) coordinates in the t-th frame using the following equation (4), and calculates the vertical displacement using the following equation (5).

[0033]

number

number

[0034] In the above formulas (4) and (5), M is the amplitude expansion ratio. disp is the display frequency stored in the frequency memory unit 31.

[0035] In addition, the display frequency f disp is the extraction frequency f tgt If the amplitude-weighted image of the extracted vibration component is equal to the extraction frequency f tgt The display frequency is f disp is the extraction frequency f tgt If the frequency is lower than f, the amplitude-weighted image of the extracted vibration component will be displayed at a lower frequency than the actual frequency, and the display frequency f disp is the extraction frequency f tgt If the display frequency is higher than f, the amplitude-weighted image of the extracted vibration component is displayed at a higher frequency than the actual frequency. disp When is "1", the amplitude weighted image of the extracted vibration component is extracted at the extraction frequency f tgt In other words, the amplitude weighted image generating unit 26 displays the vibration components of the extracted object at a specified display frequency f disp The amplitude-emphasised image generating unit 26 generates a moving image that is displayed so as to oscillate at a certain angle as an amplitude-emphasised image. The amplitude-emphasised image generating unit 26 outputs the generated amplitude-emphasised image to the image output unit 40.

[0036] The storage unit 30 includes a frequency storage unit 31, a reference image storage unit 32, a latest image storage unit 33, a frame number storage unit 34, an all-point displacement storage unit 35, a Fourier coefficient storage unit 36, a maximum amplitude storage unit 37, and an amplitude expansion ratio storage unit 38. Such a storage unit 30 stores the moving image input to the image input unit 10 and various information (data) processed by the processing unit 20. The storage unit 30 is realized by, for example, a volatile or non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), or the like.

[0037] The frequency memory unit 31 stores the extraction frequency f set by the frequency setting unit 21. tgt and display frequency f disp The reference image storage unit 32 stores the first frame of the moving image input to the image input unit 10, and the latest image storage unit 33 stores the next and subsequent frames of the same moving image. The frame number storage unit 34 stores the frame number of the moving image input to the image input unit 10.

[0038] The all-point displacement storage unit 35 stores the all-point displacements calculated by the all-point displacement calculation unit 23. The Fourier coefficient storage unit 36 ​​stores the Fourier coefficients and moving averages at all points calculated by the Fourier coefficient moving average calculation unit 24. The maximum amplitude storage unit 37 stores the maximum value of the amplitude calculated by the maximum amplitude calculation unit 25. The amplitude magnification ratio storage unit 38 stores a predetermined amplitude magnification ratio.

[0039] The image output unit 40 outputs the amplitude-weighted image generated by the amplitude-weighted image generating unit 26 of the processing unit 20. The image output unit 40 may output the amplitude-weighted image to the outside, or may output the amplitude-weighted image to the outside by displaying it. That is, the image output unit 40 may include, for example, an output interface such as a USB (Universal Serial Bus) port, or a display device such as a liquid crystal display device.

[0040] The vibration visualization device 1 can be realized by a computer such as a personal computer or a workstation. When the vibration visualization device 1 is realized by a computer, the functions of each unit of the vibration visualization device 1 are realized by a program for realizing those functions being executed by a CPU (Central Processing Unit) provided in the computer. In other words, the functions of each unit of the vibration visualization device 1 are realized by the cooperation of software and hardware resources. The vibration visualization device 1 may be realized by using hardware such as a Field-Programmable Gate Array (FPGA), a Large Scale Integration (LSI), or an Application Specific Integrated Circuit (ASIC).

[0041] Fig. 2 is a flowchart showing an example of a vibration visualization method according to an embodiment of the present invention. The process of the flowchart shown in Fig. 2 is started, for example, when a user issues an instruction to start visualization to the vibration visualization device 1. It is assumed that a moving image of an object captured by an imaging device such as a camera is input to the image input unit 10 of the vibration visualization device 1. In addition, in the following, for the sake of simplicity of explanation, the extraction frequency f tgt and display frequency f disp is stored in advance in the frequency storage unit 31.

[0042] 2 starts, first, the storage control unit 22 stores the first frame of the moving image input to the image input unit 10 in the reference image storage unit 32 (step S11). Next, the storage control unit 22 stores the image of the next frame of the moving image input to the image input unit 10 in the latest image storage unit 33 (step S12).

[0043] Next, the image stored in the reference image storage unit 32 and the image stored in the latest image storage unit 33 are read out, and the all-point displacement calculation unit 23 performs a process of calculating the all-point displacement (step S13). Specifically, the image read out from the reference image storage unit 32 is used as a reference, and a process of calculating the displacement (all-point displacement) for all pixels of the image read out from the latest image storage unit 33 is performed. The calculated all-point displacement is stored in the all-point displacement storage unit 35 of the storage unit 30 by the reference image storage unit 32.

[0044] Next, the Fourier coefficient moving average calculation unit 24 calculates a Fourier coefficient and a moving average with the previously calculated Fourier coefficient (step S14). Specifically, the all-point displacements stored in the all-point displacement storage unit 35 and the extraction frequencies stored in the frequency storage unit 31 are read out, and the Fourier coefficients at the read-out extraction frequencies are calculated for each of all points within the field of view of the moving image. Then, the moving averages between the newly calculated Fourier coefficients and the previously calculated Fourier coefficients are calculated for each of all points. In the initial state, the previously calculated Fourier coefficients are set to zero.

[0045] For example, for each point (x, y) in the field of view of the video, the Fourier coefficient U t (x, y) is calculated, and the Fourier coefficient of the vertical displacement V is calculated using the above-mentioned equation (2). t A process of calculating (x, y) is performed. The Fourier coefficients and moving averages at all the points thus calculated are stored in the Fourier coefficient storage unit 36 ​​by the Fourier coefficient moving average calculation unit 24.

[0046] Next, the Fourier coefficients are read from the Fourier coefficient storage unit 36, and the maximum amplitude calculation unit 25 performs a process of calculating the maximum amplitude value from the read Fourier coefficients (step S15). For example, the maximum amplitude value R t The calculated maximum amplitude value is stored in maximum amplitude storage unit 37 by maximum amplitude calculation unit 25.

[0047] Next, the amplitude-weighted image generating unit 26 performs a process of calculating a displacement value at the current time using the Fourier coefficient (moving average) and generating an amplitude-weighted image (step S16). disp , and the maximum amplitude value R t are read out by the amplitude-weighted image generating unit 26. Then, the amplitude-weighted image generating unit 26 performs a process of determining the displacement value at the current time for each of all points using the read out Fourier coefficients (moving averages).

[0048] The amplitude expansion ratio read from the amplitude expansion ratio storage unit 38 is compared with the maximum amplitude R t The amplitude-weighted image generating unit 26 then performs a process of calculating a new magnification ratio. The amplitude-weighted image generating unit 26 then performs a process of performing motion compensation on the image read from the reference image storage unit 32 using the displacement values ​​at all of the calculated points, which are enlarged by the newly calculated magnification ratio, to generate an amplitude-weighted image. Note that the generated amplitude-weighted image is generated by applying a motion compensation to the image read from the reference image storage unit 32, where the vibration components of the extracted object are displayed at a frequency f disp The amplitude-weighted image is a moving image displayed to vibrate at a certain frequency. The above processing is, for example, the processing expressed by the above-mentioned expressions (4) and (5). The generated amplitude-weighted image is output to the image output unit 40 by the amplitude-weighted image generating unit 26.

[0049] Next, the processing unit 20 judges whether visualization has ended (step S17). For example, it judges whether the user has instructed the vibration visualization device 1 to end visualization. If it is judged that visualization has not ended (if the judgment result in step S17 is "NO"), the process returns to step S12, and the processes of S12 to S17 are performed again. On the other hand, if it is judged that visualization has ended (if the judgment result in step S17 is "YES"), the series of processes shown in FIG. 2 ends.

[0050] As described above, in this embodiment, the extraction frequency f tgt This allows the Fourier coefficients of the fourier transform to be calculated. As a result, the processing load is lighter and the processing time is extremely short compared to the conventional method of calculating the Fourier coefficients by performing a Fourier transform and an inverse transform on the most recent N samples, making it possible to check the vibration state of the target object in real time.

[0051] In this embodiment, the amplitude magnification ratio is set to the maximum amplitude R t Therefore, the maximum vibration point on the screen can be visualized with an amplitude that is always easy to see (for example, 100 pixels) while keeping the parameter M given by the user as the magnification rate fixed. This allows the extraction frequency f tgt It becomes easy to see the shape of the vibration at various frequencies while changing

[0052] Furthermore, in this embodiment, the display frequency f disp Therefore, the extraction frequency f tgt Regardless of the frequency, the extracted vibration components of the object can be visualized at any frequency that is easily visible.

[0053] The vibration visualization device, vibration visualization method, and vibration visualization program according to one embodiment of the present invention have been described above, but the present invention is not limited to the above-described embodiment and can be freely modified within the scope of the present invention. For example, in the above embodiment, for the sake of simplicity, an example has been described in which the first frame of an input video is set as the reference frame. However, the reference frame is not limited to the first frame of an input video, and any frame of an input video can be set as the reference frame. [Explanation of symbols]

[0054] 1 Vibration visualization device 21 Frequency setting section 23 All-point displacement calculation section 24 Fourier coefficient moving average calculation section 25 Maximum amplitude calculation section 26 Amplitude-enhanced image generation unit

Claims

1. 1. A vibration visualization device that performs image processing on a moving image obtained by photographing an object to visualize a vibration state of the object, an all-point displacement calculation unit that sequentially calculates all-point displacements, which are displacements at all points within a field of view of the moving image, for each frame obtained after a reference frame of the moving image, based on the reference frame; a Fourier coefficient moving average calculation unit that calculates, for each of all of the points, a Fourier coefficient at an extraction frequency that is a frequency of a vibration component to be extracted from the latest all-point displacement calculated by the all-point displacement calculation unit, and calculates, for each of the points, a moving average with respect to the previously calculated Fourier coefficient; an amplitude-emphasised image generating unit that calculates a displacement value at a current time for each of all of the points using the Fourier coefficients calculated by the Fourier coefficient moving average calculating unit, and performs motion compensation for the reference frame using values ​​obtained by enlarging the displacement values ​​by a predetermined enlargement rate to generate an amplitude-emphasised image; A vibration visualization device comprising:

2. a maximum amplitude calculation unit that calculates a maximum amplitude from the Fourier coefficients of all the points calculated by the Fourier coefficient moving average calculation unit; the amplitude-emphasized image generating unit uses a value obtained by dividing a preset amplitude expansion rate by the maximum amplitude value calculated by the maximum amplitude calculating unit as the predetermined expansion rate. The vibration visualization device according to claim 1.

3. 3. The vibration visualization device according to claim 1, wherein the amplitude-emphasized image generation unit generates, as the amplitude-emphasized image, a moving image in which the extracted vibration component of the object is displayed as vibrating at a specified display frequency.

4. The vibration visualization device according to claim 3 , further comprising a frequency setting unit that sets the extraction frequency.

5. The vibration visualization device according to claim 4 , wherein the frequency setting section sets the display frequency.

6. 1. A vibration visualization method for visualizing a vibration state of an object by performing image processing on a moving image obtained by photographing the object, comprising: determining all-point displacements, which are displacements at all points within a field of view of the moving image, for each frame obtained after a reference frame of the moving image as a reference; From the latest displacements of all the points, a Fourier coefficient at an extraction frequency, which is a frequency of a vibration component to be extracted, is obtained for each of the points, and a moving average with respect to the previously obtained Fourier coefficient is calculated for each of the points; a displacement value at a current time is calculated for each of all the points using the calculated Fourier coefficients, and the displacement value is expanded by a predetermined expansion rate, and then motion compensation is performed on the reference frame using the expanded value to generate an amplitude weighted image. Vibration visualization method.

7. On the computer, determining all-point displacements, which are displacements at all points within a field of view of a moving image obtained by photographing an object, for each frame obtained after a reference frame of the moving image as a reference; From the latest displacements of all the points, a Fourier coefficient at an extraction frequency, which is a frequency of a vibration component to be extracted, is obtained for each of the points, and a moving average of the previously obtained Fourier coefficient is calculated for each of the points; a displacement value at a current time is calculated for each of all the points using the calculated Fourier coefficients, and the displacement value is expanded by a predetermined expansion rate, and then motion compensation is performed on the reference frame using the expanded value to generate an amplitude weighted image. A vibration visualization program to make this happen.

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