Detection system and detection method

Abstract

To provide a detection system and a detection method that can suppress wrong detection on whether there is a disturbance.SOLUTION: A detection system comprises an imaging part configured to acquire a captured image including a first region and a second region provided at least in part around the first region, and a control part, and the second region includes an image of the enclosure of the imaging part or a fitted part of the imaging part. The control part is configured to determine whether there is a disturbance based upon the second region, and then perform processing based upon a detection result in the first region according to the determination result about whether there is a disturbance.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present disclosure relates to a detection system and a detection method.

Background Art

[0002] Patent Document 1 discloses a lighting control device that controls each of a plurality of lighting fixtures for illuminating a lighting space. The lighting control device includes an acquisition unit, a detection unit, a control unit, a determination unit, and a switching unit. The acquisition unit acquires a captured image from an image sensor that captures the lighting space. The detection unit detects the position and brightness of a person in the lighting space from the captured image. The control unit controls the plurality of lighting fixtures. The determination unit determines whether external light is incident on the lighting space. The switching unit switches the operation mode of the control unit to a first mode when it is determined by the determination unit that external light is incident, and to a second mode when it is determined that external light is not incident.

[0003] In the first mode, the control unit receives both the detection results of the position and brightness of the person from the detection unit, and collectively performs dimming control on the plurality of lighting fixtures so that the brightness becomes a predetermined target value when a person is present in the lighting space. In the second mode, the control unit receives the detection result of the position of the person from the detection unit, and is configured to individually control the plurality of lighting fixtures according to the position of the person regardless of the brightness when a person is present in the lighting space.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In Patent Document 1, the determination unit uses the amplification factor of the AGC (Automatic Gain Control) circuit in the image sensor to determine whether external light is incident on the illumination space. However, for example, a human shadow or the like may affect the determination of the presence or absence of external light.

[0006] An object of the present disclosure is to obtain a detection system and a detection method capable of suppressing false detection of the presence or absence of disturbance.

Means for Solving the Problems

[0007] The detection system according to the present disclosure includes an imaging unit configured to acquire an imaging image including a first region and at least a part of the periphery of the first region, and a control unit. The second region includes an image of the housing of the imaging unit or the attached portion of the imaging unit. The control unit discriminates the presence or absence of disturbance based on the second region, and is configured to perform processing based on the detection result in the first region according to the discrimination result of the presence or absence of disturbance.

[0008] The detection method according to the present disclosure acquires an imaging image including a first region and at least a part of the periphery of the first region by an imaging unit, discriminates the presence or absence of disturbance based on the second region, and performs processing based on the detection result in the first region according to the discrimination result of the presence or absence of disturbance. The second region includes an image of the housing of the imaging unit or the attached portion of the imaging unit.

Advantages of the Invention

[0009] According to the detection system and the detection method according to the present disclosure, the presence or absence of disturbance is discriminated based on at least a part of the periphery of the first region in the imaging image. Therefore, false detection of the presence or absence of disturbance can be suppressed.

Brief Description of the Drawings

[0010]

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Mode for Carrying Out the Invention

[0011] The detection system and detection method according to the present embodiment will be described with reference to the drawings. The same or corresponding components may be denoted by the same reference numerals, and the repeated description may be omitted.

[0012] Embodiment 1. FIG. 1 is a diagram showing the configuration of the lighting control system 100 according to Embodiment 1. The detection system and detection method of the present embodiment can be applied to, for example, the lighting control system 100. The lighting control system 100 includes a lighting network controller 10, a lighting controller 11, an LED lighting fixture 12, various terminals 14, various sensors 15, a wall switch 16, and a control terminal for controlling the LED lighting fixture 12. The control terminal includes, for example, a control unit 18, a dimming signal terminal 19, a dimming controller 17, and an integrated operator 21. The sensor 15 includes, for example, an illuminance and occupancy sensor, an illuminance sensor, an occupancy sensor master unit, an illuminance and occupancy sensor slave unit, and an image sensor 50.

[0013] The integrated operator 21 and the lighting network controller 10 are connected, for example, by a LAN (Local Area Network) cable and communicate via BACnet. The lighting network controller 10 and the lighting controller 11 are connected, for example, by a LAN cable and communicate using a lighting control protocol. The lighting controller 11, the LED lighting fixture 12, the terminal 14, the sensor 15, the wall switch 16, and the control terminal are connected by a lighting control communication line 13 and communicate with each other. An amplifier 20 may be connected to the lighting control communication line 13.

[0014] FIG. 2 is a perspective view of the image sensor 50 according to Embodiment 1. FIG. 3 is a front view of the image sensor 50 according to Embodiment 1. FIG. 4 is a plan view of the image sensor 50 according to Embodiment 1. The image sensor 50 includes, for example, a housing 51, an infrared transmitter 53, an operation state display LED 54, a detection state display LED 55, an infrared receiver 56, and an imaging unit 60. The infrared transmitter 53, the operation state display LED 54, the detection state display LED 55, the infrared receiver 56, and the imaging unit 60 are exposed from the opening of the frame 52 of the housing 51.

[0015] The imaging unit 60 is an imaging device such as a camera module or a CMOS (Complementary Metal Oxide Semiconductor) sensor. It is advisable to use a wide-angle CMOS sensor with an angle of view close to 180° as the imaging unit 60. For example, by using a wide-angle lens, the angle of view of the CMOS sensor can be widened. The imaging unit 60 is attached near the center of the housing 51.

[0016] As shown in FIG. 2, the imaging unit 60 is attached deeper than the frame 52. That is, when the image sensor 50 is attached to the ceiling, the imaging unit 60 is attached at a position higher than the frame 52. The heights of the imaging unit 60 and the frame 52 may be the same. The imaging unit 60 performs imaging through an opening formed in the frame 52. From the above configuration, the housing 51 will be reflected in the captured image of the imaging unit 60.

[0017] FIG. 5 is a diagram for explaining the detection area of the image sensor 50 according to the first embodiment. The image sensor 50 is attached to the ceiling 70, for example. Area A3 is the image area of the image sensor 50 on the floor surface. Area A2 is the detection area of the image sensor 50 at a predetermined height from the floor surface. Area A1 is inside Area A2 and indicates the detection range of the image sensor 50.

[0018] FIG. 6 is a diagram for explaining an example of a captured image of the image sensor 50 according to the first embodiment. FIG. 6 is an example of the video seen by the imaging unit 60 of the image sensor 50 attached to the ceiling 70. The central part of the captured image is a first area used, for example, for detecting human movement for lighting control. The first area corresponds to Area A1 in FIG. 5, for example. Also, the area where the frame 52 of the housing 51 is reflected around the first area is defined as the second area.

[0019] FIG. 7 is a diagram for explaining a first region R1 and a second region R2 in the captured image according to the first embodiment. The first region R1 is a central region partitioned in a grid pattern in FIG. 7. The second region R2 is, for example, a region at the four corners of the first region R1. However, the second region R2 is not limited to this, and may include the entire periphery of the first region R1. The second region R2 may be a region provided at at least a part of the periphery of the first region R1.

[0020] The imaging unit 60 is configured to acquire a captured image including the first region R1 and the second region R2. As described above, the image of the second region R2 includes the image of the edge of the opening of the housing 51. Also, depending on the position of the CMOS sensor and performance such as the angle of view, the ceiling 70 may be included in the captured image. That is, the image of the second region R2 may include the image of the mounted portion of the imaging unit 60. Thus, the second region R2 may include the image of the housing 51 of the imaging unit 60 or the mounted portion of the imaging unit 60.

[0021] In the present embodiment, the presence or absence of disturbance is discriminated by using the change in the captured image in the second region R2. The disturbance indicates, for example, illumination or natural light. FIG. 8 is a functional block diagram of the image sensor 50 according to the first embodiment. The image sensor 50 includes an imaging unit 60 and a control unit 61. The control unit 61 discriminates the presence or absence of disturbance based on the second region R2 of the captured image acquired by the imaging unit 60. Also, the control unit 61 is configured to perform processing based on the detection result in the first region R1 according to the discrimination result of the presence or absence of disturbance. The control unit 61 can be realized by various arithmetic devices such as a processor and a computer. The control unit 61 may be constituted by a plurality of arithmetic devices.

[0022] Figures 9 to 11 are diagrams for explaining the human motion detection process according to Embodiment 1. The control unit 61 is configured to detect human motion from the difference in the images of the first region R1. First, as shown in FIG. 9, the control unit 61 acquires screen captures at regular intervals by the imaging unit 60 and compares the acquired images. The control unit 61 calculates, for example, the amount of change in pixel values for each pixel. Based on the calculated amount of change in pixel values, the control unit 61 determines that the pixel has "motion" when the amount of change is a certain value or more. In FIG. 10, the regions P1 to P4 surrounded by frames are the portions determined to have "motion".

[0023] When the size of the block of pixels determined to have "motion" is a certain value or more, the control unit 61 determines that it is a person. Also, when the size of the block of pixels determined to have "motion" is less than a certain value, the control unit 61 regards it as undetected. In the example of FIG. 11, regions P1, P2, and P3 are determined to be people, and P4 is undetected.

[0024] Figures 12 and 13 are diagrams for explaining the change in the image of the housing 51 when the illumination changes. The determination of the presence or absence of disturbance is performed based on the luminance change in an area where people do not pass, such as the above-described second region R2. That is, the control unit 61 determines the presence or absence of disturbance based on the change in the brightness of the image of the second region R2. For the detection of disturbance, the algorithm for detecting human motion described above can be used. The detection location of motion is, for example, the four corners of the captured image acquired by the imaging unit 60.

[0025] The control unit 61 acquires screen captures at regular intervals by the imaging unit 60 and compares the acquired images. The control unit 61 calculates, for example, the amount of change in pixel values for each pixel. Based on the calculated amount of change in pixel values, the control unit 61 determines that the pixel has "motion" when the amount of change is a certain value or more. In FIG. 13, the region surrounded by the frame is the region determined to have "motion". Since the second region R2 is not an area where people move, it is not necessary to perform the determination based on the size of the block of pixels shown in FIG. 11.

[0026] FIG. 14 is a flowchart showing the human motion detection process according to Embodiment 1. The control unit 61 acquires a captured image, that is, a captured picture, from the imaging unit 60 (step S1). Next, the control unit 61 cuts out a disturbance determination image, that is, a second region R2, used for disturbance determination from the captured image (step S2). The control unit 61 compares the disturbance determination image acquired in the same manner one frame before with the current disturbance determination image and determines whether there is a change (step S3). The presence of a change means the presence of a disturbance, and the absence of a change means the absence of a disturbance. When there is a change, that is, when there is a disturbance, the detection of human motion in the subsequent first region is not performed.

[0027] When there is no change, that is, when there is no disturbance, the control unit 61 executes a human motion analysis process (step S4). That is, when the control unit 61 determines that there is no disturbance based on the second region R2, it detects the human motion in the first region. The control unit 61 controls the LED lighting fixture 12 according to the detected human motion. The control unit 61 switches the on / off setting of the lighting, for example, according to the presence or absence of human motion (step S5).

[0028] In addition, the control unit 61 can calculate the illuminance not only for human motion. FIG. 15 is a flowchart showing the illuminance calculation process according to Embodiment 1. Steps S1 and S2 are the same as the human motion detection process. In step S3, the usage of the result of the disturbance determination is the opposite of that in the human motion detection process. When there is no disturbance, the control unit 61 does not calculate the illuminance. When there is a disturbance, the control unit 61 calculates the illuminance. The control unit 61 calculates the illuminance in both the first region R1 affected by lighting control and the second region R2 (steps S24, S25, S26).

[0029] In the first region R1, the illuminance value may deviate from the actual illuminance change depending on the situation in the area. Therefore, the final illuminance value is calculated with reference to the illuminance value calculated in the second region R2. That is, when the control unit 61 determines that there is a disturbance based on the second region R2, it calculates the illuminance using the first region R1 and the second region R2. The calculated illuminance may be notified to the cloud. The accuracy may be improved by using AI analysis or the like for the illuminance calculation.

[0030] When calculating the illuminance using the second region R2, it is preferable that the portion of the housing 51 reflected in the captured image has an appearance of an intermediate gradation region when the captured image is grayscaled. The portion of the housing 51 reflected in the captured image is preferably, for example, a gray color that is an intermediate color between black and white. Thereby, when the captured image of the image sensor 50 is a monochrome image, the pixel value of the housing 51 reflected in the captured image is a value near the center, for example, between 100 and 150, out of 0 to 255 gradations. At this time, even if a change in illuminance occurs, the pixel value of the image of the housing 51 does not become a state of white jump with a pixel value of 255 or a state of black crush with a pixel value of 0. Therefore, the accuracy of illuminance calculation can be improved. Note that the appearance of the housing 51 may be a color tone other than gray as long as it is near the middle 128 of 256 gradations in the image grayscaled by the camera module.

[0031] Next, the effects of the present embodiment will be described. In an image sensor that uses a CMOS sensor and detects human movement based on changes in an image, there has been a possibility of erroneously detecting the movement of a shadow caused by disturbance or the color tone of the clothes of the detected person as a change in luminance due to external light.

[0032] In contrast, in the present embodiment, the imaging unit 60 acquires a captured image including the first region R1 and the second region R2 provided at least partially around the first region R1, and determines the presence or absence of disturbance based on the second region R2. The second region R2 includes an image of the housing 51 of the imaging unit 60 or the attached portion of the imaging unit 60. Therefore, false detection of the presence or absence of disturbance can be suppressed. That is, by using the wide-angle lens to utilize the housing 51 or the ceiling projected as a region not affected by human movement for disturbance determination, disturbance can be detected accurately.

[0033] Also, in the present embodiment, processing based on the detection result in the first region R1 is performed according to the determination result of the presence or absence of disturbance based on the second region R2. Thereby, for example, detection of human movement in the first region and lighting control based on the detection result of human movement can be accurately performed. Further, by utilizing the second region R2 that is not affected by human movement for illuminance calculation, the illuminance can be accurately calculated.

[0034] Processing other than detection of human movement or illuminance calculation may be performed according to the determination result of the presence or absence of disturbance based on the second region R2. Further, the detection system and detection method of the present embodiment may be applied to any system other than the lighting control system.

[0035] In the present embodiment, the configuration in which the imaging unit 60 and the control unit 61 that determines the presence or absence of disturbance are integrally incorporated in the image sensor 50 has been described as an example. However, the present invention is not limited to this, and the imaging unit 60 and the control unit 61 may be separately arranged. For example, the control unit 61 may be provided in a control terminal, a lighting controller 11, an external server, or the like.

[0036] The technical features described in the present embodiment may be used in appropriate combination.

[0037] Hereinafter, various aspects of the present disclosure will be collectively described as appendices. (Appendix 1) An imaging unit configured to acquire an imaging image including a first region and at least a part of the periphery of the first region; A control unit; Comprising: The second region includes an image of the housing of the imaging unit or the attachment portion of the imaging unit; The control unit is configured to determine the presence or absence of disturbance based on the second region, and perform processing based on the detection result in the first region according to the determination result of the presence or absence of disturbance. A detection system characterized by this. (Appendix 2) The detection system according to Appendix 1, wherein the control unit detects human movement in the first region when it is determined that there is no disturbance based on the second region. (Appendix 3) When the control unit determines that there is disturbance based on the second area, the detection system according to Appendix 1 or 2, characterized in that it calculates illuminance using the first area and the second area. (Appendix 4) The imaging unit performs imaging through an opening formed in the housing. The image of the second area includes an image of an edge of the opening of the housing. The detection system according to any one of Appendices 1 to 3, characterized in that. (Appendix 5) The image of the second area includes an image of an attachment part of the imaging unit. The detection system according to any one of Appendices 1 to 4, characterized in that. (Appendix 6) The image of the second area includes an image of the housing. A part of the housing that appears in the captured image has an appearance that becomes a middle tone area when the captured image is grayscale. The detection system according to any one of Appendices 1 to 5, characterized in that. (Appendix 7) The control unit determines the presence or absence of disturbance based on a change in brightness of the image of the second area. The detection system according to any one of Appendices 1 to 6, characterized in that. (Appendix 8) An imaging unit acquires a captured image including a first area and a second area provided at least partially around the first area. The presence or absence of disturbance is determined based on the second area, and processing based on the detection result in the first area is performed according to the determination result of the presence or absence of disturbance. The second area includes an image of a housing of the imaging unit or an attachment part of the imaging unit. A detection method, characterized in that. (Appendix 9) When it is determined that there is no disturbance based on the second area, the detection method according to Appendix 8, characterized in that it detects the movement of a person in the first area. (Appendix 10) The detection method according to appended note 8 or 9, characterized in that when it is determined that there is the disturbance based on the second area, illuminance is calculated using the first area and the second area.

Explanation of reference numerals

[0038] 10 Lighting network controller, 11 Lighting controller, 12 LED lighting fixture, 13 Lighting control communication line, 14 Terminal device, 15 Sensor, 16 Wall switch, 17 Dimmer controller, 18 Control unit, 19 Dimming signal terminal device, 20 Amplifier, 21 Integrated operator, 50 Image sensor, 51 Housing, 52 Frame, 53 Infrared transmitter, 54 Operating state display LED, 55 Detection state display LED, 56 Infrared receiver, 60 Imaging unit, 61 Control unit, 70 Ceiling, 100 Lighting control system, R1 First area, R2 Second area

Claims

1. An imaging unit configured to acquire an imaging image including a first region and a second region provided at least partially around the first region; A control unit; Comprising: The second region includes an image of the housing of the imaging unit or the mounted portion of the imaging unit; The control unit is configured to determine the presence or absence of interference based on the second region, and perform processing based on the detection result in the first region according to the determination result of the presence or absence of interference. A detection system characterized by that.

2. The detection system according to claim 1, wherein when the control unit determines that there is no interference based on the second region, the control unit detects the movement of a person in the first region.

3. The detection system according to claim 1, wherein when the control unit determines that there is interference based on the second region, the control unit calculates the illuminance using the first region and the second region.

4. The imaging unit performs imaging through an opening formed in the housing, The detection system according to any one of claims 1 to 3, wherein the image of the second region includes an image of an edge of the opening of the housing.

5. The detection system according to any one of claims 1 to 3, wherein the image of the second region includes an image of the mounted portion of the imaging unit.

6. The image of the second region includes an image of the housing, The detection system according to any one of claims 1 to 3, wherein a portion of the housing that appears in the imaging image has an appearance that becomes a middle tone region when the imaging image is grayscale-converted.

7. The detection system according to any one of claims 1 to 3, wherein the control unit determines the presence or absence of interference based on a change in brightness of the image of the second region.

8. An imaging unit acquires an imaging image including a first region and a second region provided at least partially around the first region; Determine the presence or absence of interference based on the second region, and perform processing based on the detection result in the first region according to the determination result of the presence or absence of interference, The second region includes an image of the housing of the imaging unit or the mounted portion of the imaging unit. A detection method characterized by that.

9. The detection method according to claim 8, wherein when it is determined that there is no interference based on the second region, the movement of a person in the first region is detected.

10. The detection method according to claim 8 or 9, characterized in that when it is determined that there is the disturbance based on the second region, illuminance is calculated using the first region and the second region.

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