JP6520269B2 - Image sensor, lighting system - Google Patents

Description

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

  According to Patent Document 1, the irradiation area of the lighting apparatus is photographed by a TV camera, the brightness and the presence or absence of a moving object are detected from the image data for each area obtained by dividing the photographed image of the TV camera into plurals. A lighting system is disclosed that dims the light output of the lighting fixture.

JP, 2013-4235, A

  The image sensor is used to determine the presence or absence of a moving body (person). Preferably, the image sensor determines the presence or absence of a person in a predetermined range of real space. However, since the height from the floor surface of the ceiling to which the image sensor is attached is not constant, the size of the real space to be photographed varies according to the height of the image sensor. That is, according to the height of the image sensor, the imaging area by the image sensor becomes wide or narrow. As the height of the image sensor from the floor increases, the imaging area widens, and conversely, as the height from the floor decreases, the imaging area narrows. Moreover, when the attachment position in planar view of an image sensor shifts | deviates from the center of the area | region which should determine the presence or absence of a person, it may become difficult to determine the presence or absence of the person of the said area | region.

  In order to avoid these adverse effects, it has been necessary to mask the areas not used for human presence / absence determination among the areas photographed by the image sensor.

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

  An image sensor according to the invention of the present application includes a camera unit and an image processing unit for acquiring an image obtained by the camera unit, and the image processing unit is based on the information of the installation height of the image sensor. A detection area corresponding to a real space of a predetermined size is specified in an imaging area photographed by a camera, and the presence or absence of a person in the detection area is determined.

A lighting system according to the invention of the present application comprises: a plurality of image sensors for detecting movement of a person, or a person's stay or absence in a plurality of blocks, a lighting controller communicating with the image sensor, and a plurality of lights controlled by the lighting controller. A lighting fixture, wherein the image sensor is information of a moving block which is a block in which movement of a person is detected among the plurality of blocks, or information of a staying block which is a block in which a person's stay is detected; Transmitting information of an absent block, which is a block in which the absence of a person is detected, to the light controller, and the light controller turns on the luminaire of the moving block when the information of the moving block is received; 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 move block is received. Is lit, when receiving information of said non stationary block, turns off the lighting fixture of the unmoving stationary block, the image sensor includes a camera portion, an image processing unit for acquiring an image obtained by the camera unit, the The image processing unit specifies a detection area corresponding to a real space of a predetermined width in the photographing area photographed by the camera unit based on the information of the installation height of the image sensor. The presence or absence of a person in the detection area is determined .

  According to the present invention, it is possible to determine the presence or absence of a person in the real space of a predetermined range simply by giving the information of the installation height of the image sensor to the image sensor using the remote control by the operator.

FIG. 1 is a block diagram showing a lighting system according to Embodiment 1. It is a figure which shows internal structures, such as 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 image | photographed by the image sensor. It is a figure which shows an imaging | photography area | region and a detection area. It is a figure which shows the imaging | photography area | region and detection area in the case where the installation height of an image sensor is 2 m and 5 m. It is a figure which shows the area etc. of the imaging | photography area in the case in which 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. 6 is a view showing an image sensor and the like according to a second embodiment. It is a top view which shows that the image sensor was installed in the equipment plate of the center part of the lighting fixture. It is a figure which shows the frame format of a communication frame.

  An image sensor and a lighting system according to an embodiment of the present invention will be described with reference to the drawings. The same or corresponding components may be assigned the same reference numerals and repetition of the description may be omitted.

Embodiment 1
FIG. 1 is a block diagram showing a lighting system according to a first embodiment. A lighting controller 12 is connected to the setting device 10. The lighting controller 12 controls the lighting devices 14, 16. The number of lighting fixtures is not particularly limited. For example, a large office is provided with hundreds of lighting fixtures. The image sensor 18 is a part which photographs the irradiation area | region of the lighting fixtures 14 and 16 with a camera, and determines the presence or absence of a person. The wall switch 20 is used by the user to turn the luminaires 14, 16 on and off.

  FIG. 2 is a view showing an internal configuration of the lighting controller 12, the lighting fixture 14, the image sensor 18, and the wall switch 20 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 part that acquires an image obtained by the camera unit 30 and determines the presence or absence of a person.

  FIG. 3 is a view showing an example of the layout of the lighting fixture 14 and the image sensor 18. For example, the irradiation area by 16 lighting fixtures 14 is divided into four into a first block B1, a second block B2, a third block B3 and a fourth block B4. One block has a width of, for example, 3.6 m × 3.6 m. The four blocks add up to an area of 7.2 m × 7.2 m. Four luminaires 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 where 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 Embodiment 1 is an area of 7.2 m × 7.2 m in real space. Therefore, the image sensor 18 only needs to be able to determine the presence or absence of a person within the range of 7.2 m × 7.2 m, and it is not necessary to determine the presence or absence of a person outside this range.

  FIG. 4 is a view 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, shooting in a wide range is possible. Specifically, an angle of view of about 65 ° (130 ° horizontal) with respect to the vertical direction is secured. In order to enable imaging in a wider range, for example, a wide-angle lens capable of imaging 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, an area (referred to as a photographing area) photographed by the image sensor 18 is 9 m × 9 m.

  FIG. 5 is a diagram showing an imaging area and a detection area. The detection area 42 of the image sensor 18 for determining the presence or absence of a person is 7.2 m × 7.2 m, whereas the imaging area 40 actually photographed by the image sensor 18 is 9 m × 9 m. The part outside the detection area 42 in the imaging area 40 is a part that is not used to determine the presence or absence of a person who has been imaged. Manually applying masking to a portion that is not used to determine the presence or absence of a person places a heavy burden on the operator.

  Therefore, in the first embodiment, the worker notifies the image sensor 18 of the information of the installation height from the floor surface of the image sensor 18 using the remote control. The information of 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 of the installation height of the image sensor 18, the image processing unit 32 detects a detection area 42 corresponding to a real space of a predetermined size in the imaging area 40 photographed by the camera unit 30. It identifies and determines the presence or absence of the person of the detection area 42. 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 the presence or absence of the person in the detection area 42 is determined. 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 determination of the presence or absence of a person in the detection area 42 by the image processing unit 32 is performed for each of the first to fourth blocks B1 to B4. For example, the determination may sequentially proceed in the order of B1, B2, B3 and B4, and the timing of performing the determination of the next block may be performed after transmitting the determination result to the lighting controller 12, and after the determination and before transmission You may do so. When the image processing unit 32 detects the presence of a person in any block, the image processing unit 32 transmits the information to the lighting controller 12 via the communication unit 34. The lighting controller 12 having received the determination information turns on the lighting fixture 14 of the block in which the presence of a person is detected. For example, when the presence of a person is detected in the B1 block of the detection area 42 specified by the image processing unit 32, the determination information is transmitted to the lighting controller 12, and the lighting controller 12 lights the lighting fixture 14 in the B1 block. On the other hand, when the image processing unit 32 determines the absence of a 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 in the block.

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

  Thus, based on the information of the installation height of the image sensor 18, the image sensor 18 is specified (cut out) as a detection area 42 corresponding to a part of the imaging area 40, that is, a real space of a predetermined size. The presence or absence of the person in the detection area 42 is determined. Thus, regardless of the installation height of the image sensor 18, the presence or absence of a person in the real space (detection area) within a predetermined range can be determined.

  FIG. 6 is a diagram showing imaging regions and detection regions in the case where the installation height of the image sensor from the floor surface is 2 m and 5 m. The lens of the camera unit 30 of the image sensor 18 of FIG. 6 is a normal lens and not a wide-angle lens. The imaging area 40 (indicated by alternate long and short dashed lines) when the installation height of the image sensor 18 is 5 m is larger than the imaging area 40 (indicated by alternate long and short dash lines) when the installation height is 2 m. Since the width of the detection area 42 is constant (7.2 m × 7.2 m) regardless of the installation height of the image sensor 18, the pixels not used as the detection area 42 as the installation height of the image sensor 18 increases. Will increase.

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

  By the way, when the installation height of the image sensor 18 is 2 m, the area difference between the imaging area 40 (9.0 m × 9.0 m) and the detection area 42 (7.2 m × 7.2 m) is small. When the installation height is 4 m, the area difference between the imaging area 40 (17 m × 17 m) and the detection area 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 It will decrease. When the installation height is 4 m, the resolution per block constituting the detection area 42 is also reduced compared to the case where the installation height is 2 m.

  As the installation height of the image sensor 18 increases, the resolution per block decreases, and it becomes difficult to determine the presence or absence of a person. That is, it is 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 allocated 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, in the case where the detection area 42 is divided into 16 × 16 blocks (256 blocks in total), the number of pixels per block tends to be small, so 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, a person is photographed small, and when the installation height of the image sensor 18 is low, a person is photographed relatively large. Therefore, according to the installation height of the image sensor 18, it is preferable to change the size of what is recognized as a person. 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 information of the installation height of the image sensor 18, and the image sensor When the installation height of 18 is low, the size of what is recognized as a person is increased to determine the presence or absence of a person. This operation is executed by the microcomputer in the image sensor 18. This can improve human recognition accuracy.

  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 according to the first embodiment has a function of setting an arbitrary place of the detection area 42 as a mask area where human detection is not performed. In this function, when the image sensor 18 is set to the mask mode (mode for setting the mask area) and the person moves at the place where the display device is installed, the image sensor 18 automatically detects the movement of the person. This is realized by setting the place where the movement is detected in the mask area. This function is realized by a microcomputer.

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

  Therefore, in the first embodiment, an ID is assigned to each of the plurality of blocks, and the image processing unit 32 is configured such that the worker can arbitrarily correct the ID. By changing the block ID using the remote control, the operator can match the position of the block to the design specification without removing or rotating the image sensor mounted in the wrong direction. The image processing unit 32 stores a program for realizing the above function.

  The hardware that implements each of the above functions is typically a microcomputer, but may be implemented by other means. Also, each of the above functions may be selected as appropriate.

  The image sensor 18 and the illumination system according to the first embodiment can be variously modified. Although the operator notifies the "information of installation height" to the image sensor 18 using a remote control, the image sensor 18 itself may store this information in a memory or the like. Moreover, although the area of the detection area 42 illustrated 7.2 m x 7.2 m, it is not specifically limited. The size of the detection area in a general office is often 3.6 m × 3.6 m or 7.2 m × 7.2 m. Further, although the detection area 42 is set to the floor surface, for example, the detection area 42 may be set to a height of 0.7 m above the floor, or may be set to a height of 1 m above the floor. In this case, person detection can be performed at the height of the sitting height of the person.

  When a wide-angle lens is used, the image processing unit 32 preferably has a distortion correction function of correcting distortion of an image captured by the camera unit 30. If the width of the imaging area 40 can be made equal to or larger than the area of the detection area 42 at the lowest possible installation height of the image sensor 18, a non-wide-angle normal lens may be used instead of the wide-angle lens. However, when the installation height of the image sensor 18 is as low as 2 m, in order to secure a detection area of 7.2 m × 7.2 m, the angle of view θ in FIG. 4 needs to be 130 ° or more. Use In the case of the camera unit 30 that captures an image 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 an SVGA (800 × 600) resolution may be used. When the installation height of the image sensor 18 is as high as, for example, 10 m, it is preferable to increase the resolution of the camera unit 30 in order to improve the accuracy of human detection. It is preferable that the image sensor 18 have a function of detecting the illuminance in addition to the detection of the presence or absence of a person.

  FIG. 8 is a diagram showing a system of the entire building. On one floor 50, a setter 10, a lighting controller 12, a lighting fixture 14, an image sensor 18 with illumination function, and a wall switch 20 are provided. The lighting fixtures 14 and the like on all the floors of the building are controlled by the lighting equipment monitoring device 52 and the building automation system (BAS) 54 via the HUB. A lighting system having the above-described image sensor 18 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 embodiment. Since the image sensor 18 and the illumination system according to the following embodiment have many points in common with the first embodiment, the differences with the first embodiment will be mainly described.

Second Embodiment
Although the image sensor 18 is provided at the center of the detection area 42 in the first embodiment, the image sensor 18 may not be provided at 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 shifted.

  FIG. 9 is a view showing the image sensor 18, the imaging area 40, and the detection area 42 according to the second embodiment. The image sensor 18 is attached at a position advanced by 2 m in the X direction and 2 m in the Y direction from the center P1 of the detection area 42. In the second embodiment, the operator operates the remote control to notify the image sensor 18 of information on 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 shifts the center P1 of the detection area 42 from the sensor installation position by the amount of positional deviation, and sets the detection area 42.

  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 photographed by the camera unit 30, and Determine the presence or absence of When the information of the installation height of the image sensor 18 is obtained in addition to the information of the positional deviation amount, the detection area 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 detection area 42 may be specified with the installation height of the image sensor 18 fixed.

  As described above, according to the image sensor according to the second embodiment, the image sensor 18 can be obtained simply by providing the 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 a facility plate at the center 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 area 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 describes various communication frame formats performed between the setter 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 the operator sends information on the installation height of the image sensor 18 to the image sensor 18. This command includes the number (sensor number) of the image sensor 18 and the installation height (installation height) of the sensor 18. The command name “sensor installation height monitor” is a command for displaying the installation height of a specific image sensor 18 on the LED display unit 38 of the image sensor 18. The command name “sensor installation location correction” is a command used when the operator sends the information on the amount of misalignment described above to the image sensor 18. This command includes the number (sensor number) of the image sensor 18 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.

Third Embodiment
The image sensor 18 according to the third embodiment detects a movement of a person or a 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 person's stay is detected because the person detected by the camera unit 30 does not move for a certain period. In addition, a person's stay typically refers to 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 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 a plurality of blocks. The information of the absent block, which is a block, is transmitted to the lighting controller 12. When the lighting controller 12 receives the information of the moving block, it turns on the lighting fixture 14 of the moving block, and when the information of the staying block is received, the lighting fixture 14 of the staying block receives the information of the moving block Turn on at a higher dimming rate than when. For example, the luminaire 14 of the moving block is turned on to achieve an illumination of 300 lux, and the luminaire 14 of the stay block is turned on to achieve an illumination of 500 lux. When the lighting controller 12 receives information on an absent block which is a 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 (seats) while avoiding the waste that makes the place where the person is moving high when the person is moving. At the same time, sufficient illuminance can be realized.

  When a person moves in a corridor or the like, if only the light of the place where the person is present is turned on, the pedestrian can not sufficiently see the moving destination. Therefore, when the information on the moving block is received, it is preferable that the lighting controller 12 predict the moving direction of the person and turn on the lighting fixture 14 of the moving destination block.

  By the way, when there is a change in luminance due to lighting or extinguishing of the lighting fixture 14, the image sensor 18 may erroneously detect a person. Therefore, it is preferable that the lighting controller 12 ignores the detection result from the image sensor 18 for a predetermined period after lighting or extinguishing, for a block to which the luminaire 14 that has been lighting or extinguishing belongs.

  The features of the image sensor and the illumination system according to each of the embodiments described above may be combined as appropriate.

  Reference Signs List 10 setter, 12 illumination controller, 14 illumination fixtures, 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 shooting area, 42 detection area

Claims (14)

Camera section,
An image processing unit for acquiring an image obtained by the camera unit;
The image processing unit specifies a detection area corresponding to a real space of a predetermined width in the photographing area photographed by the camera unit based on the information of the installation height of the image sensor, and detects the detection area. An image sensor characterized by determining presence or absence of a person in a region. Camera section,
An image processing unit for acquiring an image obtained by the camera unit;
The image processing unit
In the imaging area photographed by the camera unit, a detection area corresponding to a real space of a predetermined size is specified, and the presence or absence of a person in the detection area is determined.
An image sensor characterized by shifting the center of the detection area from the installation position of the image sensor by the displacement amount when the position shift amount between the installation position of the image sensor and the center of the detection area is given.   The image sensor according to claim 1 or 2, wherein an area of the detection area is 3.6 m x 3.6 m or 7.2 m x 7.2 m.   The image sensor according to any one of claims 1 to 3, wherein the camera unit comprises a wide-angle lens.   The image sensor according to any one of claims 1 to 4, wherein the image processing unit divides the detection area into a plurality of blocks and determines the presence or absence of a person for each block.   6. The image sensor according to claim 5, wherein the image processing unit divides the detection area into a plurality of blocks such that at least 20 × 20 pixels are allocated to one block.   The image processing unit reduces the size of what is recognized as a person when the installation height of the image sensor is high based on the information of the installation height of the image sensor, and when the installation height of the image sensor is low The image sensor according to any one of claims 1 to 6, wherein the presence or absence of a person is determined by enlarging the size of the recognition object.   The image sensor according to any one of claims 1 to 7, wherein the image processing unit has a function of setting an arbitrary place of the detection area as a mask area in which a person is not detected. . An ID is assigned to each of the plurality of blocks,
The image sensor according to claim 5, wherein the image processing unit is configured to allow an operator to arbitrarily correct the ID.   5. The image sensor according to claim 4, wherein the image processing unit includes a distortion correction function that corrects distortion of an image captured by the camera unit.   The image processing unit shifts the center of the detection area from the installation position of the image sensor by the positional deviation amount when the positional deviation amount between the installation position of the image sensor and the center of the detection area is given. The image sensor according to claim 1, characterized in that: 12. The image sensor according to any one of claims 1 to 11, which detects a movement of a person or a person's stay or absence in a plurality of blocks.
A lighting controller in communication with the image sensor;
A plurality of lighting fixtures controlled by the lighting controller;
The image sensor detects 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 the absence of a person is detected. Transmitting information of an absent block, which is a new block, to the lighting controller,
The lighting controller is
When the information of the moving block is received, the lighting fixture of the moving block is turned on,
When the information of the stay block is received, the lighting fixture of the stay block is turned on at a higher dimming rate than when the information of the move block is received,
A lighting system, wherein the luminaire of the absent block is turned off when the information of the absent block is received.   The lighting system according to claim 12, wherein, upon receiving the information on the moving block, the lighting controller predicts a moving direction of a person and turns on a lighting fixture of a moving destination block. The image sensor detects the presence or absence of a person in the plurality of blocks,
The lighting controller lights a lighting fixture of a block detected by a person by the image sensor.
14. The light controller according to claim 12, wherein the light controller ignores a detection result from the image sensor for a predetermined period of time after lighting or extinguishing of a block to which the luminaire belongs. Lighting system described.

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