Flashing light counting method and device

Abstract

To provide a blinking light spot counting method and an apparatus therefor which can precisely count the number of blinking light spots from a moving image.SOLUTION: A blinking light spot counting apparatus (200) has: a moving image storing unit (202) for storing moving image data at a predetermined frame rate having captured blinking light spots blinking at a predetermined blinking period; a frame extracting unit (203) for extracting a frame image at a time interval of the blinking period from the moving image data; a frame superimposing unit (204) for generating a superimposed frame image by superimposing the extracted frame images on each other; and a light spots counting unit (205) for counting light spots based on the superimposed frame image.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for counting the number of light points that blink at a predetermined period.

Background Art

[0002] The number of fireflies that emit light is a typical example of an indicator showing the state of the ecosystem or natural environment of a rural area. However, it is not easy to count fireflies that blink and emit light, and it is particularly difficult to count fireflies that are not flying. Therefore, usually, in the case of Genji fireflies and Heike fireflies, a method is adopted in which a person visually counts within a partitioned area within 2 hours after sunset when the fireflies are flying (see Non-Patent Document 1).

[0003] In addition, a method of counting the number of individuals using an image has also been proposed. For example, Patent Document 1 discloses an individual number counting apparatus that divides an imaging screen into a plurality of small regions and obtains the number of individuals in the entire screen from the sum of the number of individuals existing in the small regions. Patent Document 2 also discloses a method of removing bright point noise when moving image-capturing a subject with low luminance by cumulatively adding image data received a plurality of times with the same or different exposure times and counting the number of individuals of the subject based on the added image data.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0005]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the individual count methods disclosed in Patent Documents 1 and 2 assume that there is a subject in the imaging screen. For this reason, when imaging an individual that blinks like a firefly, the light spot may or may not exist depending on the imaging frame, and the exact number of individuals cannot be counted from the imaging screen.

[0007] The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a blinking light spot counting method and apparatus capable of accurately counting the number of blinking light spots from a moving image.

Means for Solving the Problems

[0008] A blinking light spot counting apparatus according to an embodiment of the present invention for achieving the above object includes a moving image storage unit that stores moving image data at a predetermined frame rate in which blinking light spots having a predetermined blinking period are imaged, a frame extraction unit that extracts frame images at time intervals of the blinking period from the moving image data, a frame superposition unit that superposes the extracted frame images to generate a single superimposed frame image, and a light spot counting unit that counts light spots based on the superimposed frame image. Further, a blinking light spot counting apparatus according to an embodiment of the present invention determines whether the light spot region included in the superimposed frame image is a plurality of light spot regions, or or a connected region consisting of a single light spot 、 and further includes a connected region determination unit that determines according to the light spot arrangement form of the light spot region, and the light spot counting unit can count light spots based on the superimposed frame image after the connected region determination. Determination of part Also, according to an embodiment of the present invention, the blinking light spot may be a blinking point of a glowing firefly. ​In addition, the blinking light point counting method according to an embodiment of the present invention stores moving image data with a predetermined frame rate in which blinking light points with a predetermined blinking period are imaged in a moving image storage unit, and a frame extraction unit extracts frame images from the moving image data at time intervals of the blinking period, a frame overlapping unit overlaps the extracted frame images to generate one overlapping frame image, and a light point counting unit counts light points based on the overlapping frame image. In addition, in the blinking light point counting method according to an embodiment of the present invention, a connected region determination unit further determines whether the light point region included in the overlapping frame image is a plurality of light point regions, or or a connected region consisting of a single light point 、 is determined according to the light point arrangement form of the light point region, and the light point counting unit can count the light points included in the overlapping frame image after the connected region determination Determination of part is performed. In addition, in the blinking light point counting method according to an embodiment of the present invention, the blinking light point can be the bright and dark point of a glowing firefly. In addition, the blinking light point counting device according to an embodiment of the present invention is a blinking light point counting device realized by a computer, and includes a moving image memory that stores moving image data with a predetermined frame rate in which blinking light points with a predetermined blinking period are imaged, a program memory that stores a program, and a processor that executes the program. The processor extracts frame images from the moving image data at time intervals of the blinking period, overlaps the extracted frame images to generate one overlapping frame image, and counts light points based on the overlapping frame image. In addition, in the blinking light point counting device according to an embodiment of the present invention, the processor determines whether the light point region included in the overlapping frame image is a plurality of light point regions, or or a connected region consisting of a single light point 、 is determined according to the light point arrangement form of the light point region, and the Determination light points can be counted based on the subsequent overlapping frame image. In addition, in the blinking light point counting device according to an embodiment of the present invention, the blinking light point can be the bright and dark point of a glowing firefly.

Advantages of the Invention

[0009] According to an embodiment of the present invention, a frame image is extracted at time intervals of the blinking period of the blinking light points, and the light points are counted based on a superimposed frame image obtained by superimposing the extracted frame images. Therefore, it is advantageous for accurately counting the number of blinking light points from a moving image. For example, if an imaging unit having a sensitivity capable of detecting light emission that is too weak to be visually confirmed is used, the counting accuracy of fireflies that are not flying can be significantly improved as compared with visual confirmation. Further, according to an embodiment of the present invention, since it is determined whether or not the light point region of the superimposed frame image is a connected region and the light points are counted, it is advantageous for correctly counting the number of light points even when a single light point is moving. Further, according to an embodiment of the present invention, it is possible to accurately count the number of individual fireflies from a moving image of the emitting fireflies.

Brief Description of the Drawings

[0010]

Figure 1

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Figure 7

Embodiments for Carrying Out the Invention

[0011] 1. First Embodiment As illustrated in FIG. 1, the imaging unit 101 captures a moving image with blinking light points G1, G2, G3,... as subjects. The blinking light point counting device 200 according to the first embodiment of the present invention includes an interface 201, a moving image storage unit 202, a frame extraction unit 203, a frame superposition unit 204, and a light point counting unit 205, and is connected to the imaging unit 101 by wire or wirelessly through the interface 201. Each function of the frame extraction unit 203, the frame superposition unit 204, and the light point counting unit 205 of the blinking light point counting device 200 can be realized by executing a program stored in a memory (not shown) on a processor.

[0012] The moving image storage unit 202 stores the moving image data input from the imaging unit 101 through the interface 201. The moving image data may be in a well-known file format having a certain frame rate. Here, it is assumed that a plurality (m) of blinking light points G1, G2, G3,... Gm are captured in the moving image. It is desirable that the moving image data input from the imaging unit 101 is subjected to image processing to remove spot noise so that the blinking light points stand out. In particular, when the blinking light point is a firefly, since the imaging is usually performed from sunset to night, the subject has a low luminance, and pre-processing for noise removal is desirable. Therefore, as the imaging unit 101, a low-noise, high-sensitivity moving image camera capable of detecting weak blinking light points (such as the light emission of fireflies) that are difficult to visually confirm can be used.

[0013] The frame extraction unit 203 extracts a plurality of frame images within a predetermined time interval from the moving image data stored in the moving image storage unit 202. The predetermined time interval is set to the blinking period P of the blinking light point G, which is the subject of the imaging unit 101, as will be described later. The frame superposition unit 204 superposes the plurality of frame images extracted by the frame extraction unit 203 as one frame to generate a superposed frame image Fs. The light point counting unit 205 counts the number of light points, which are high-luminance regions, by scanning the superposed frame image Fs.

[0014] As illustrated in FIG. 2, m blinking light points G1, G2, G3... Gm are captured in the moving image, but each light point blinks at a predetermined period P and is not necessarily synchronized. Therefore, as shown in FIG. 2, if all the frame images included in a time interval (frame extraction period) equal to the blinking period P are extracted from the moving image data, or only the number obtained by thinning out at a predetermined interval is extracted, then in a series of the extracted frame images, light points corresponding to one lighting period of each blinking light point should be recorded. The frame extraction period only needs to be equal to the blinking period P and can be set at any timing. In the case of an individual firefly in which the blinking light point G emits light, the blinking period P varies depending on the type of firefly or the habitat area. Therefore, observe the fireflies inhabiting the location where the number of individuals is to be counted in advance to determine the blinking period P.

[0015] As illustrated in FIG. 3, assume that n extracted frame images F1 to Fn are included in the frame extraction period P. The number of frames n may depend on the frame rate of the moving image, which is the number of all frames within the frame extraction period P, or may be the number obtained by thinning out all the frame images within the frame extraction period P at a constant interval. However, this thinning interval needs to be shorter than at least the length of the lighting period. In FIG. 3, three blinking light points G1 to G3 are illustrated to avoid complication. In each frame image, the light points marked with "X" are the non-lighting light points, and the others are the lighting light points. For example, in the extracted frame image F3, the light points G1 and G2 are not lit, and only the light point G3 is lit.

[0016] The frame overlapping unit 204 overlaps such extracted frame images F1 to Fn to generate one overlapping frame image Fs. Since this overlapping frame image Fs includes here the frame images in which each of the three blinking light points G1 to G3 was lit, by overlapping them, all three blinking light points G1 to G3 are recorded as light points. Therefore, the light point counting unit 205 can obtain the number (m = 3) of all the blinking light points G1 to G3 by counting the light points G1 to G3.

[0017] The graph illustrated in FIG. 4 shows the result of counting the number of blinking light points in a video for each frame number when changing the number of frames to be superimposed. It can be seen that if the number of frames n is too large, the count will increase when there are moving blinking light points (here, moving fireflies), and if the number of frames n is too small, the count will decrease. Therefore, it is desirable to adjust the frame extraction period based on the actual blinking period of the fireflies to obtain a more accurate count of the blinking light points.

[0018] 2. Second Embodiment According to the second embodiment of the present invention, the counting of the blinking light points is performed considering the case where the blinking light points move. The main difference from the first embodiment is that for the superimposed frame image Fs, a connected region determination is performed to determine whether the blinking light points move or not. Hereinafter, it will be described with reference to FIGS. 5 and 6.

[0019] As illustrated in FIG. 5, as already described, the imaging unit 101 captures a moving image with the blinking light points G1, G2, G3,... as subjects. The blinking light point counting device 300 according to the second embodiment of the present invention includes an interface 301, a moving image storage unit 302, a frame extraction unit 303, a frame superimposing unit 304, a connected region determination unit 304, and a light point counting unit 205, and is connected to the imaging unit 101 by wire or wirelessly through the interface 301. Each function of the frame extraction unit 303, the frame superimposing unit 304, the connected region determination unit 305, and the light point counting unit 306 of the blinking light point counting device 300 can be realized by executing a program stored in a memory (not shown) on a processor.

[0020] The moving image storage unit 302 stores the moving image data input from the imaging unit 101, as in the first embodiment. The frame extraction unit 303 extracts a plurality of frame images included in the frame extraction period of the blinking period P from the moving image data stored in the moving image storage unit 302 (by thinning out at regular intervals or without thinning out). The frame superimposing unit 304 generates a superimposed frame image Fs by superimposing a plurality of frame images extracted by the frame extraction unit 203 as one frame. Note that in this embodiment, the frame extraction period can also be set to a period longer than the blinking period P.

[0021] The connected region determination unit 305 determines whether a light point region composed of a plurality of light points in the superimposed frame image Fs is a connected region caused by the movement of one light point or a set of a plurality of light points, and outputs the superimposed frame image Fsc determined to be connected to the light point counting unit 306. Such a connection determination can be performed by matching with the movement form of a light point (here, a firefly) in advance or by image recognition using machine learning. The light point counting unit 306 executes counting of light points according to the superimposed frame image Fsc determined to be connected by the connected region determination unit 305. An example is shown in FIG. 6.

[0022] As illustrated in FIG. 6, assume that light point regions C1 to C3 exist in the superimposed frame image Fs. Since the light points in the light point region C1 cannot be separated due to the resolution, it is impossible to determine whether a plurality of light points overlap or it is one light point. In this case, considering that the probability of a plurality of light points accidentally coinciding completely is low, it is determined that the light point region C1 is one light point G1. In the light point region C2, four light points can be identified, and the positions of these light points vary, so the probability of forming one moving line is low. Therefore, it is determined that the light point region C2 is four separate light points G2 to G5. In the light point region C3, five light points can be identified, but it is determined that the arrangement form of these light points is a connected region forming one moving line, that is, the result of the movement of one light point G6. In this way, the connected region determination unit 305 performs a connection determination on the superimposed frame image Fs and generates a superimposed frame image Fsc after the connection determination. Therefore, the light point counting unit 306 can obtain the number (m = 6) of blinking light points G1 to G6 from the superimposed frame image Fsc after the connection determination.

[0023] 3. Third Embodiment The flashing light point counting devices 200 and 300 according to the above-described first and second embodiments can be realized on a computer. Also, the imaging unit 101 is not limited to one, and a plurality of imaging units 101 can also be used. Hereinafter, as a third embodiment of the present invention, an example using a plurality of cameras that can be network-connected as the imaging unit 101 will be described.

[0024] As illustrated in FIG. 7, the plurality of cameras 401 are wirelessly connected to a wireless communication unit 402 that is an access point, and moving images within the imaging ranges of the respective cameras 401 are input to the flashing light point counting device 500 through the wireless communication unit 402. When counting the number of fireflies, it is sufficient that the entire habitat to be observed can be covered by the imaging ranges of the plurality of cameras 401.

[0025] The flashing light point counting device 500 according to the present embodiment can be mounted on a computer including a processor 501, a moving image memory 502, a program memory 503, an input unit 504, and a display unit 505. By executing the program in the program memory 503, the processor 501 can realize the functions of the frame extraction unit 203, the frame overlapping unit 204, and the light point counting unit 205 of the first embodiment described above, and can also realize the functions of the frame extraction unit 303, the frame overlapping unit 304, the connected region determination unit 305, and the light point counting unit 306 of the second embodiment described above. The moving image memory 502 corresponds to the moving image storage units 202 and 302 of the first and second embodiments described above. Therefore, since the operation of the flashing light point counting device 500 according to the present embodiment is the same as that of the flashing light point counting devices 200 and 300 according to the first and second embodiments described above, a detailed description thereof will be omitted.

[0026] The input unit 504 of the flashing light point counting device 500 according to the present embodiment is an input device such as a keyboard, and for example, the flashing period P in the first and second embodiments can be input. The display unit 505 is a monitor, which displays the light point count value counted in the first and second embodiments, and may also display the superimposed frame image Fs illustrated in FIG. 3 or the superimposed frame image Fsc after connection determination illustrated in FIG. 6 together with the flashing light points.

[0027] In addition, in the present embodiment, the camera 401 is wirelessly connected to the flashing light point counting device 500, but it is not limited thereto and may be wired-connected. Also, a plurality of the flashing light point counting devices 200 according to the first embodiment or 300 according to the second embodiment described above may be provided, and one or a plurality of cameras 401 may be connected to each flashing light point counting device wirelessly or by wire. Further, since the camera 401 performs imaging from sunset to night, it is desirable to use a high-sensitivity video camera, thereby enabling accurate counting of the number of fireflies that emit weak flashing light that cannot be confirmed visually from the moving image.

Description of Reference Numerals

[0028] 101 Imaging unit 200, 300, 500 Flashing light point counting device 201, 301 Interface 202, 302 Moving image storage unit 203, 303 Frame extraction unit 204, 304 Frame superimposing unit 205, 306 Light point counting unit 305 Connection area determination unit 401 Camera 402 Wireless communication unit 501 Processor 502 Moving image memory 503 Program memory 504 Input unit 505 Display unit

Claims

1. A moving image storage unit that stores moving image data of a predetermined frame rate in which blinking light points with a predetermined blinking period are imaged; A frame extraction unit that extracts frame images at time intervals of the blinking period from the moving image data; A frame superimposing unit that superimposes the extracted frame images to generate one superimposed frame image; A light point counting unit that counts light points based on the superimposed frame image; A blinking light point counting device, characterized by comprising the above.

2. The blinking light point counting device further comprises a connected region determination unit that determines whether the light point region included in the superimposed frame image is a plurality of light point regions or a connected region consisting of a single light point, according to the light point arrangement form of the light point region; The light point counting unit counts light points based on the superimposed frame image after the determination by the connected region determination unit. The blinking light point counting device according to Claim 1, characterized by this.

3. The blinking light point counting device according to Claim 1 or 2, characterized in that the blinking light point is the bright and dark point of a firefly that emits light.

4. Store moving image data of a predetermined frame rate in which blinking light points with a predetermined blinking period are imaged in a moving image storage unit; A frame extraction unit extracts frame images at time intervals of the blinking period from the moving image data; A frame superimposing unit superimposes the extracted frame images to generate one superimposed frame image; A light point counting unit counts light points based on the superimposed frame image; A blinking light point counting method, characterized by this.

5. A connected region determination unit determines whether the light point region included in the superimposed frame image is a plurality of light point regions or a connected region consisting of a single light point, according to the light point arrangement form of the light point region; The light point counting unit counts light points based on the superimposed frame image after the determination by the connected region determination unit. The blinking light point counting method according to Claim 4, characterized by this.

6. The blinking light point is the bright and dark point of a firefly that emits light. The blinking light point counting method according to Claim 4 or 5, characterized by this.

7. A blinking light point counting device realized by a computer, comprising: A moving image memory that stores moving image data of a predetermined frame rate in which blinking light points with a predetermined blinking period are imaged; A program memory that stores a program; A processor that executes the program; The processor: Extracts frame images at time intervals of the blinking period from the moving image data; Superimposes the extracted frame images to generate one superimposed frame image; Counting the light points based on the superimposed frame image A blinking light point counting device characterized by the above.

8. The processor determines whether the light point region included in the superimposed frame image is a plurality of light point regions or a connected region composed of a single light point according to the light point arrangement form of the light point region, and counts the light points based on the superimposed frame image after the determination. The blinking light point counting device according to claim 7, characterized by the above.

9. The blinking light point counting device according to claim 7 or 8, characterized in that the blinking light point is the bright and dark point of a firefly that emits light.

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