JP6693590B2 - Image sensor, lighting system - Google Patents

Description

  The present invention relates to an image sensor used for detecting a moving body and an illumination system using the image sensor.

  In Patent Document 1, the irradiation area of the lighting fixture is photographed by a TV camera, and the brightness and the presence or absence of a moving object are detected from the image data for each area obtained by dividing the image taken by the TV camera into a plurality of areas, and based on the detection result. A lighting system for dimming the light output of a luminaire is disclosed.

JP, 2013-4235, A

  The image sensor is used to determine the presence or absence of a moving body (person). The image sensor preferably determines the presence or absence of a person in the real space within a predetermined range. However, since the height of the ceiling where the image sensor is attached from the floor surface is not constant, the size of the real space in which the image is captured varies depending on the height of the image sensor. That is, the imaging area of the image sensor becomes wider or narrower depending on the height of the image sensor. The higher the height of the image sensor from the floor surface, the wider the photographing area, and conversely, the lower the height from the floor surface, the smaller the photographing area. In addition, if the mounting position of the image sensor in plan view deviates from the center of the region where the presence / absence of a person should be determined, it may be difficult to determine the presence / absence of a person in the region.

  In order to avoid these adverse effects, it is necessary to perform a work of masking an area that is not used for determining the presence / absence of a person among areas captured by the image sensor.

  The present invention has been made to solve the above problems, and provides an image sensor and an illumination system that can determine the presence or absence of a person in a real space within a predetermined range regardless of the position of the image sensor. The purpose is to do.

  An image sensor according to the invention of the present application includes a camera unit and an image processing unit that acquires an image obtained by the camera unit, and the image processing unit is the size of an object photographed by the camera unit. Based on the above, a detection area corresponding to a real space having a predetermined size is specified in the imaging area, and the presence or absence of a person in the detection area is determined.

  An illumination system according to the invention of the present application includes a plurality of image sensors for detecting movement, staying or absence of a person in a plurality of blocks, a lighting controller communicating with the image sensor, and a plurality of lighting controllers controlled by the lighting controller. A lighting fixture is provided, and the image sensor has information of a moving block, which is a block in which movement of a person is detected, or information of a stay block, which is a block in which a person's stay is detected, among the plurality of blocks, or , Information of an absent block, which is a block in which the absence of a person is detected, is transmitted to the lighting controller, and when the lighting controller receives the information of the moving block, the lighting device of the moving block is turned on, When the information of the stay block is received, the luminaire of the stay block has a higher dimming rate than when the information of the moving block is received. When the information on the absent block is turned on, the lighting device of the absent block is turned off, and the image sensor includes a camera unit and an image processing unit that acquires an image obtained by the camera unit. The image processing unit specifies a detection region corresponding to a real space of a predetermined size in the photographing region based on the size of the object photographed by the camera unit, and detects the detection region. It is characterized by determining the presence or absence of the person.

  According to the present invention, an operator can determine the presence / absence of a person in a real space within a predetermined range only by giving information on the installation height of the image sensor to the image sensor using the remote controller.

3 is a block diagram showing an illumination system according to Embodiment 1. FIG. It is a figure which shows the internal structure of an image sensor. It is a figure which shows the example of a layout of a lighting fixture and an image sensor. It is a figure which shows the area | region imaged by an image sensor. It is a figure showing a photography field and a detection field. It is a figure which shows the imaging | photography area | region and detection area in case the installation height of an image sensor is 2 m and 5 m. It is a figure which shows the width etc. of the imaging | photography area in case the installation height of an image sensor is 2 m and 4 m. It is a figure which shows the system of the whole building. FIG. 7 is a diagram showing an image sensor and the like according to a second embodiment. It is a top view which shows that an image sensor was installed in the equipment plate of the center part of a lighting fixture. It is a figure which shows the frame format of a communication frame.

  An image sensor and an illumination system according to an embodiment of the present invention will be described with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and repeated description may be omitted.

Embodiment 1.
FIG. 1 is a block diagram showing an illumination system according to the first embodiment. The lighting controller 12 is connected to the setting device 10. The lighting controller 12 controls the lighting fixtures 14 and 16. The number of lighting fixtures is not particularly limited. For example, a large office is equipped with hundreds of lighting fixtures. The image sensor 18 is a part that determines the presence / absence of a person by photographing the irradiation areas of the lighting fixtures 14 and 16 with a camera. The wall switch 20 is used by a user to turn on / off the luminaires 14 and 16.

  FIG. 2 is a diagram showing an internal configuration of the lighting controller 12, the lighting fixture 14, the image sensor 18, and the wall switch 20, which are connected by a transmission line. The image sensor 18 includes a camera unit 30, an image processing unit 32, a communication unit 34, a remote control transmission / reception unit 36, and an LED display unit 38. The image processing unit 32 is a unit that acquires an image obtained by the camera unit 30 and determines the presence or absence of a person.

  FIG. 3 is a diagram showing a layout example of the lighting fixture 14 and the image sensor 18. For example, the irradiation area of the 16 luminaires 14 is divided into four, that is, a first block B1, a second block B2, a third block B3, and a fourth block B4. One block has an area of, for example, 3.6 m × 3.6 m. When the four blocks are summed, the area is 7.2 m × 7.2 m. Four lighting fixtures 14 are provided in one block. This block is the area illuminated by the four luminaires 14.

  The image sensor 18 is provided at the center of the four blocks B1 to B4. An area in which the presence or absence of a person should be determined by the image sensor 18 is referred to as a “detection area”. The detection area in the first embodiment is an area of 7.2 m × 7.2 m in the real space. Therefore, the image sensor 18 only needs to be able to determine the presence / absence of a person within the range of 7.2 m × 7.2 m, and it is not necessary to determine the presence / absence of a person outside this range.

  FIG. 4 is a diagram showing an area photographed by the image sensor 18. The image sensor 18 is installed at a height of 2 m from the floor surface. By providing a wide-angle lens in the camera unit 30 of the image sensor 18, it is possible to shoot a wide range. Specifically, an angle of view of about 65 ° (130 ° horizontal) with respect to the vertical direction is secured. In order to enable shooting in a wider range, for example, a wide-angle lens capable of shooting a range of 185 ° with respect to the vertical direction may be used.

  The resolution of the camera unit 30 of the image sensor 18 is, for example, SXGA (1280 × 1024 pixels). The effective range of the image in this case is 1024 × 1024 pixels. As shown in FIG. 4, the area imaged by the image sensor 18 (referred to as an imaging area) is 9 m × 9 m.

  FIG. 5 is a diagram showing a shooting area and a detection area. The detection area 42 of the image sensor 18 in which presence / absence of a person is to be determined is 7.2 m × 7.2 m, whereas the shooting area 40 actually shot by the image sensor 18 is 9 m × 9 m. A portion of the photographing area 40 outside the detection area 42 is a portion which is photographed but is not used for determining the presence or absence of a person. It is a heavy burden on the operator to manually mask a portion that is not used for determining the presence or absence of a person.

  Therefore, in the first embodiment, the operator notifies the image sensor 18 of information on the installation height of the image sensor 18 from the floor surface by using the remote controller. The information on the installation height is transmitted to the image processing unit 32 via the remote control transmission / reception unit 36 of the image sensor 18. Then, based on the information on the installation height of the image sensor 18, the image processing unit 32 determines the detection area 42 corresponding to the real space of a predetermined size in the imaging area 40 imaged by the camera unit 30. The presence or absence of a person in the detection area 42 is determined. Specifically, the image processing unit 32 identifies (cuts out) the detection area 42 in the imaging area 40 of FIG. 5 based on the installation height of the image sensor 18, and determines the presence or absence of a person in the detection area 42. judge. When cutting out the detection area 42 from the imaging area 40, the digital zoom function of the camera unit 30 can be used.

  The presence / absence of a person in the detection area 42 is determined by the image processing unit 32 for each of the first to fourth blocks B1-B4. This determination may proceed sequentially in the order of, for example, B1, B2, B3, B4, and the timing of determining the next block may be performed after transmitting the determination result to the illumination controller 12, or after the determination and before transmission. You may do it. Then, when the image processing unit 32 detects the presence of a person in any of the blocks, the image processing unit 32 transmits the information to the illumination controller 12 via the communication unit 34. The lighting controller 12 that has received this determination information turns on the lighting device 14 of the block that has detected the presence of a person. For example, when the image processing unit 32 detects the presence of a person in the B1 block of the detection area 42 specified, the determination information is transmitted to the lighting controller 12, and the lighting controller 12 turns on the lighting fixture 14 of the B1 block. On the other hand, when the image processing unit 32 determines that there is no person in the block, the determination information is transmitted to the lighting controller 12, and the lighting controller 12 turns off the lighting fixture 14 of the block.

  Examples of the hardware configuration of the image processing unit 32 include a memory that stores a program, a CPU that executes the program in the memory, and a processing circuit such as a system LSI. A plurality of processing circuits may cooperate to realize the above function.

  In this way, the image sensor 18 is specified (cut out) as a part of the imaging region 40, that is, as the detection region 42 corresponding to the real space of a predetermined size, based on the information on the installation height of the image sensor 18. The presence or absence of a person in the detection area 42 is determined. This makes it possible to determine the presence or absence of a person in the real space (detection area) within a predetermined range regardless of the installation height of the image sensor 18.

  FIG. 6 is a diagram showing a shooting area and a detection area when the installation height of the image sensor from the floor is 2 m and 5 m. The lens of the camera unit 30 of the image sensor 18 in FIG. 6 is a normal lens, not a wide-angle lens. The shooting area 40 (shown by a chain line) when the installation height of the image sensor 18 is 5 m is larger than the shooting area 40 (shown by a chain line) when the installation height is 2 m. Since the size of the detection area 42 is constant (7.2 m × 7.2 m) regardless of the installation height of the image sensor 18, the higher the installation height of the image sensor 18, the more pixels that are not used as the detection area 42. Will increase.

  FIG. 7 is a diagram showing the size of the imaging region when the installation height of the image sensor from the floor is 2 m and when the height is 4 m. When the installation height of the image sensor 18 is 2 m, the image sensor 18 detects the installation area 42 (7.2 m) in the photographing area 40 (9.0 m × 9.0 m) based on the installation height information of the image sensor 18. X 7.2 m) is specified, and the presence or absence of a person in the detection area 42 is determined. Similarly, when the installation height of the image sensor 18 is 4 m, the image sensor 18 also detects the detection area 42 (7.2 m ×) in the photographing area 40 (17 m × 17 m) based on the installation height information of the image sensor 18. 7.2 m) is specified, and the presence or absence of a person in the detection area 42 is determined. Therefore, the presence / absence of a person in the detection area 42 can be determined regardless of the installation height of the image sensor 18.

  By the way, when the installation height of the image sensor 18 is 2 m, the area difference between the imaging region 40 (9.0 m × 9.0 m) and the detection region 42 (7.2 m × 7.2 m) is small, but When the installation height is 4 m, the area difference between the imaging region 40 (17 m × 17 m) and the detection region 42 (7.2 m × 7.2 m) is large. Therefore, the resolution of the detection area 42 when the installation height of the image sensor 18 is 2 m is 433 × 433 pixels, whereas the resolution of the detection area 42 when the installation height of the image sensor 18 is 4 m is 216 × 216 pixels. Will fall. When the installation height is 4 m, the resolution per block constituting the detection area 42 is also lower than that when the installation height is 2 m.

  As the installation height of the image sensor 18 increases, the resolution per block decreases, making it difficult to determine the presence or absence of a person. That is, it becomes difficult for the image processing unit 32 to determine the presence or absence of a person for each block. Therefore, in the first embodiment, the image processing unit 32 divides the detection area 42 into a plurality of blocks so that at least 20 × 20 pixels are assigned to one block. If 20 × 20 pixels are assigned to one block, the presence or absence of a person can be accurately determined. For example, when the detection area 42 is divided into 16 × 16 blocks (a total of 256 blocks), the number of pixels per block tends to decrease, so that at least 20 × 20 pixels are secured as described above. This is very important.

  When the installation height of the image sensor 18 is high, the person is photographed small, and when the installation height of the image sensor 18 is low, the person is photographed relatively large. Therefore, it is preferable to change the size of what is recognized as a person according to the installation height of the image sensor 18. Therefore, in the first embodiment, the image processing unit 32 reduces the size of what is recognized as a person when the installation height of the image sensor 18 is high, based on the installation height information of the image sensor 18, When the installation height of 18 is low, the size of the object recognized as a person is increased to determine the presence or absence of the person. This operation is executed by the microcomputer in the image sensor 18. Thereby, the recognition accuracy of the person can be improved.

  A person may be displayed on a display device such as a television, and the image sensor 18 may erroneously detect the person. Therefore, the image processing unit 32 of the first embodiment has a function of setting an arbitrary place in the detection area 42 as a mask area in which a person is not detected. This function is such that when a person moves in a place where the display device is installed after the image sensor 18 is set to a mask mode (a mode for setting a mask area), the image sensor 18 automatically detects the movement of the person and This is achieved by setting the location where motion is detected in the mask area. This function is realized by a microcomputer.

  The direction of the block may be specified in the design specifications. For example, when four blocks are defined as shown in FIG. 3, the third and fourth blocks B3 and B4 should be provided on the window side (right side) and the first and second blocks B1 and B2 should be provided on the corridor side (left side). May be specified. However, if the image sensor 18 is fixed in the direction opposite to the design specifications due to a work mistake, the third and fourth blocks B3 and B4 are provided on the corridor side (left side), and the first and second blocks B1 and B2 is provided on the window side (right side). In this case, if the image sensor 18 is removed or rotated, the gypsum board on the ceiling will be damaged.

  Therefore, in the first embodiment, the image processing unit 32 is configured so that the IDs are respectively assigned to the plurality of blocks and the operator can arbitrarily correct the IDs. By changing the ID of the block using the remote controller, the operator can match the position of the block with the design specifications without removing or rotating the image sensor attached in the wrong direction. The image processing unit 32 stores a program that realizes the above functions.

  The hardware that implements each of the above functions is typically a microcomputer, but may be implemented by another means. Further, the above functions may be appropriately selected.

  Various modifications can be made to the image sensor 18 and the illumination system according to the first embodiment. Although the operator notifies the image sensor 18 of “information about the installation height” by using the remote controller, the image sensor 18 itself may store this information in a memory or the like. Further, the size of the detection region 42 is exemplified as 7.2 m × 7.2 m, but is not particularly limited. The size of the detection area in a typical office is often 3.6 m × 3.6 m or 7.2 m × 7.2 m. Further, although the detection area 42 is set on the floor surface, the detection area 42 may be set at a height of 0.7 m above the floor, or the detection area 42 may be set at a height of 1 m above the floor. In this case, the person can be detected by the sitting height of the person.

  When the wide-angle lens is used, the image processing unit 32 preferably has a distortion correction function that corrects the distortion of the image captured by the camera unit 30. If the size of the imaging region 40 can be made larger than the size of the detection region 42 at the lowest installation height of the image sensor 18 to be assumed, a non-wide-angle normal lens may be used instead of the wide-angle lens. However, in order to secure a detection area of 7.2 m × 7.2 m when the installation height of the image sensor 18 is as low as 2 m, the angle of view θ in FIG. To use. In the case of the camera unit 30 shooting in the 4: 3 shooting area 40, the lens angle is, for example, 185 ° in the longitudinal direction and 135 ° in the lateral direction.

  The resolution of the camera unit 30 is not particularly limited. For example, a camera having a resolution of SVGA (800 × 600) may be used. When the installation height of the image sensor 18 is as high as 10 m, for example, it is preferable to increase the resolution of the camera unit 30 in order to improve the accuracy of human detection. The image sensor 18 preferably has a function of detecting illuminance in addition to detecting the presence or absence of a person.

  FIG. 8 is a diagram showing the system of the entire building. On one floor 50, a setting device 10, a lighting controller 12, a lighting fixture 14, an image sensor 18 with an illuminance function, and a wall switch 20 are provided. The lighting fixtures 14 and the like on all floors of the building are controlled by the lighting equipment monitoring device 52 and the building automation system (BAS) 54 via the HUB. The lighting system including the image sensor 18 described above can be suitably applied to such a building system.

  These modifications can be appropriately applied to the image sensor 18 and the illumination system according to the following embodiments. Note that the image sensor 18 and the illumination system according to the following embodiments have many common points with the first embodiment, and therefore the differences from the first embodiment will be mainly described.

Embodiment 2.
Although the image sensor 18 is provided in the center of the detection area 42 in the first embodiment, the image sensor 18 may not be provided in the center of the room (detection area 42) due to the layout. In this case, the image sensor installation position and the center of the detection area 42 are displaced.

  FIG. 9 is a diagram showing the image sensor 18, the photographing region 40, and the detection region 42 according to the second embodiment. The image sensor 18 is attached at a position that is advanced by -2 m in the X direction and 2 m in the Y direction from the center P1 of the detection region 42. In the second embodiment, the operator operates the remote controller to notify the image sensor 18 of the amount of positional deviation between the installation position of the image sensor 18 and the center P1 of the detection area 42. Then, the image processing unit 32 that has received the information sets the detection area 42 by shifting the center P1 of the detection area 42 from the sensor installation position by the amount of displacement.

  After setting the detection area 42, the image sensor 18 specifies the detection area 42 corresponding to the real space of a predetermined size in the imaging area 40 imaged by the camera unit 30, and detects the person in the detection area 42. The presence or absence of is determined. When the information about the installation height of the image sensor 18 is obtained in addition to the information about the positional deviation amount, the detection region 42 may be specified by the method described in the first embodiment based on the information. On the other hand, when there is no information on the installation height of the image sensor 18, the installation height of the image sensor 18 may be fixed and the detection area 42 may be specified.

  As described above, according to the image sensor according to the second embodiment, the operator only needs to provide the image sensor 18 with information on the amount of positional deviation between the installation position of the image sensor 18 and the center P1 of the detection area. Can correct the positional deviation and set a desired detection area 42. Therefore, regardless of the position of the image sensor 18, the presence or absence of a person in the detection area 42 can be determined.

  FIG. 10 is a plan view showing that the image sensor 18 is installed on the equipment plate in the central portion of the lighting fixture 14. As described above, even when the image sensor 18 and the lighting fixture 14 are integrally provided, the presence or absence of a person in the detection region 42 can be easily determined by performing the above-described positional deviation correction.

  FIG. 11 is a diagram showing a frame format of a communication frame. FIG. 11 shows a frame format of various communications performed between the setting device 10, the lighting controller 12, the lighting fixture 14, the image sensor 18, and the wall switch 20. The command name “sensor installation height setting” is a command used when an operator sends information about the installation height of the image sensor 18 to the image sensor 18. This command includes the number of the image sensor 18 (sensor number) and the installation height (installation height) of the image sensor 18. The command name “sensor installation height monitor” is a command for displaying the installation height of the specific image sensor 18 on the LED display unit 38 of the image sensor 18. The command name “correction of sensor installation location” is a command used when the operator sends the information of the above-mentioned positional deviation amount to the image sensor 18. This command includes the number of the image sensor 18 (sensor number) and the amount of positional deviation (X position, Y position) between the installation position of the image sensor 18 and the center of the detection area 42.

Embodiment 3.
The image sensor 18 according to the third embodiment detects the movement or stay of a person in a plurality of blocks. For example, the movement of a person is detected from the difference between the images acquired by the camera unit 30, and the stay of the person is detected because the person detected by the camera unit 30 does not move for a certain period. A person's stay typically means a state in which a person is seated.

  Then, the image sensor 18 detects information of a moving block, which is a block in which the movement of a person is detected, information of a staying block that is a block in which the staying of a person is detected, or the absence of a person, among the plurality of blocks. Information of the absent block, which is the closed block, is transmitted to the lighting controller 12. When the lighting controller 12 receives the information of the moving block, the lighting controller 12 turns on the lighting device 14 of the moving block, and when the information of the stay block is received, the lighting controller 12 receives the lighting device 14 of the stay block and receives the information of the moving block. Light at a higher dimming rate than when. For example, the lighting fixture 14 of the moving block is turned on so as to achieve an illuminance of 300 lux, and the lighting fixture 14 of the stay block is turned on so as to achieve an illuminance of 500 lux. When the lighting controller 12 receives the information of the absent block, which is the block in which the absence of a person is detected, the lighting controller 12 turns off the lighting fixture 14 of the absent block.

  In this way, by making the illuminance of the stay block higher than that of the moving block, the person stays (seated) while avoiding the waste of increasing the illuminance of the place where the person is moving when the person is moving. A sufficient illuminance can be achieved when

  When a person is moving in a corridor or the like, if only the lighting of the place where the person is present is turned on, the pedestrian cannot sufficiently see the moving destination. Therefore, when the lighting controller 12 receives the information of the moving block, it is preferable to predict the moving direction of the person and turn on the lighting device 14 of the moving block.

  By the way, the image sensor 18 may erroneously detect a person when there is a change in the brightness caused by turning on or off the lighting fixture 14. Therefore, it is preferable that the illumination controller 12 ignores the detection result from the image sensor 18 for a predetermined period after the lighting or extinguishing of the block to which the lighting fixture 14 belongs is turned on or off.

  The features of the image sensor and the illumination system according to each of the embodiments described so far may be appropriately combined and used.

  10 setting device, 12 lighting controller, 14 lighting equipment, 18 image sensor, 20 wall switch, 30 camera unit, 32 image processing unit, 34 communication unit, 36 remote control transmission / reception unit, 38 LED display unit, 40 imaging region, 42 detection region

Claims (2)

Camera part,
An image processing unit for acquiring an image obtained by the camera unit,
The image processing unit,
Based on the size of the object imaged by the camera unit, a detection area corresponding to a real space having a predetermined size is specified in the imaging area, and the presence or absence of a person in the detection area is determined. An image sensor characterized in that A plurality of image sensors according to claim 1, which detect movement or stay of a person in a plurality of blocks, and absent.
A lighting controller in communication with the image sensor,
A plurality of lighting fixtures controlled by the lighting controller;
The image sensor, of the plurality of blocks, information of a moving block that is a block in which the movement of a person is detected, or information of a stay block that is a block in which the stay of a person is detected, or the absence of a person is detected. Information of the absent block, which is a closed block, is transmitted to the lighting controller,
The lighting controller is
When receiving the information of the moving block, turn on the lighting equipment of the moving block,
When the information of the stay block is received, the lighting equipment of the stay block is lit at a higher dimming rate than when the information of the moving block is received,
A lighting system, wherein when the information of the absent block is received, the lighting equipment of the absent block is turned off.

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