Person detection system, room entry / exit determination system, person detection method, and program

Abstract

The purpose of the present disclosure is to provide a person detection system, a room entry / exit determination system, a person detection method, and a program that make it possible to accurately detect whether a person is present regardless of the height at which a temperature acquisition unit is installed. A human detection system (1) comprises a temperature acquisition unit (11), a filter (12), a detection unit (141), a height acquisition unit (13), and a parameter setting unit (142). The temperature acquisition unit (11) acquires information related to the temperature in a detection region (X1) as a thermal image. The detection unit (141) detects whether a person (A1) is present in the detection region (X1) on the basis of the thermal image averaged by the filter (12). The height acquisition unit (13) acquires an installation height, which is the height at which the temperature acquisition unit (11) is installed. The parameter setting unit (142) sets a parameter related to the averaging by the filter (12) in accordance with the installation height.

Description

Human detection system, entrance / exit determination system, human detection method, and program

[0001] The present disclosure generally relates to a human detection system, an entrance / exit determination system, a human detection method, and a program. More specifically, the present disclosure relates to a human detection system, an entrance / exit determination system, a human detection method, and a program for detecting whether a person is present or not.

[0002] Patent Document 1 discloses a passing person number measuring device that measures the number of people who have passed through a predetermined detection area. The passing person number measuring device includes a thermal image generation unit, a difference image generation unit, a first noise removal processing unit, and a measurement unit. The thermal image generation unit generates a thermal image related to the detection area every time a time Δt elapses. The difference image generation unit generates a first difference image that is a difference image between the thermal image generated at time t and the thermal image generated at time t + Δt. The first noise removal processing unit performs a first noise removal process on the first difference image. The measurement unit measures the number of people who have passed through the detection area based on a second difference image that is the difference image after the first noise removal process.

[0003] By the way, depending on the height at which a temperature acquisition unit such as the thermal image generation unit of Patent Document 1 is installed, the measurement unit (detection unit) may not be able to accurately detect whether a person is present or not.

[0004] Japanese Patent Application Laid-Open No. 2024-39742

[0005] An object of the present disclosure is to provide a human detection system, an entrance / exit determination system, a human detection method, and a program that can accurately detect whether a person is present or not regardless of the height at which a temperature acquisition unit is installed.

[0006] A person detection system according to one aspect of the present disclosure comprises a temperature acquisition unit, a filter, a detection unit, a height acquisition unit, and a parameter setting unit. The temperature acquisition unit acquires information regarding the temperature in a detection area as a thermal image. The filter averages the thermal image. The detection unit detects whether or not a person is present in the detection area based on the thermal image averaged by the filter. The height acquisition unit acquires the installation height, which is the height at which the temperature acquisition unit is installed. The parameter setting unit sets parameters related to the averaging by the filter according to the installation height.

[0007] An entry / exit determination system according to one aspect of the present disclosure comprises the person detection system and a determination unit. The determination unit determines, based on the detection result of the detection unit, whether or not the person has passed through a detection line that is set in advance inside the detection area.

[0008] A person detection method according to one aspect of the present disclosure includes a temperature acquisition step, an averaging step, a detection step, a height acquisition step, and a parameter setting step. In the temperature acquisition step, information regarding the temperature in the detection area is acquired as a thermal image. In the averaging step, the thermal image is averaged. In the detection step, whether or not a person is present in the detection area is detected based on the thermal image that has been averaged in the averaging step. In the height acquisition step, the installation height, which is the height at which the temperature acquisition unit that acquires the thermal image is installed, is acquired. In the parameter setting step, parameters related to the averaging in the averaging step are set according to the installation height.

[0009] A program relating to one aspect of this disclosure is a program that causes a computer system to execute the person detection method.

[0010] Figure 1 is a schematic diagram of the human detection system and the entry / exit determination system according to this embodiment. Figure 2 is an explanatory diagram illustrating the detection area of ​​the temperature acquisition unit of the human detection system when the installation height is the same as the expected height. Figure 3 is an explanatory diagram illustrating the detection area of ​​the temperature acquisition unit of the human detection system when the installation height is lower than the expected height. Figure 4 is an explanatory diagram illustrating the detection area of ​​the temperature acquisition unit of the human detection system when the installation height is higher than the expected height. Figure 5 is a flowchart illustrating the human detection method of the human detection system and the entry / exit determination method of the entry / exit determination system. Figure 6 is a flowchart illustrating the determination steps in the entry / exit determination method of the entry / exit determination system.

[0011] The embodiments and modifications described below are merely examples of the present disclosure. This disclosure is not limited to these embodiments and modifications, and various modifications are possible depending on the design, etc., as long as they do not depart from the technical idea of ​​the present disclosure. The figures described in the embodiments and modifications below are schematic diagrams, and the ratios of the size and thickness of each component in the figures do not necessarily reflect the actual dimensional ratios.

[0012] (Embodiment) (1) Overview Below, an overview of the human detection system 1 according to this embodiment will be described with reference to Figures 1 and 2.

[0013] As shown in Figure 1, the person detection system 1 according to this embodiment includes a temperature acquisition unit 11, a filter 12, a detection unit 141, a height acquisition unit 13, and a parameter setting unit 142.

[0014] The temperature acquisition unit 11 acquires information about the temperature in the detection area X1 (see Figure 2) as a thermal image. The filter 12 averages the thermal image acquired by the temperature acquisition unit 11. The detection unit 141 detects whether or not a person is present in the detection area X1 based on the thermal image averaged by the filter 12. The height acquisition unit 13 acquires the installation height, which is the height at which the temperature acquisition unit 11 is installed. The parameter setting unit 142 sets parameters related to the averaging of the thermal image by the filter 12 according to the installation height of the temperature acquisition unit 11 acquired by the height acquisition unit 13.

[0015] From the above, in the person detection system 1 of this embodiment, the filter 12 can average thermal images suitable for the installation height at which the temperature acquisition unit 11 is installed. Therefore, the detection unit 141 detects whether or not a person is present in the detection area X1 based on the thermal image that has been averaged to suit the installation height at which the temperature acquisition unit 11 is installed. In other words, the person detection system 1 of this embodiment has the advantage of being able to accurately detect whether or not a person is present regardless of the installation height at which the temperature acquisition unit 11 is installed.

[0016] (2) Detailed Configuration (2.1) Entry / Exit Determination System The detailed configuration of the entry / exit determination system 10 of this embodiment will be described below with reference to Figures 1 to 4.

[0017] As shown in Figure 1, the entry / exit determination system 10 of this embodiment comprises a person detection system 1 and a management device 2. The entry / exit determination system 10 of this embodiment determines whether person A1 (see Figure 2) has entered or exited by passing through a detection line Y1 that is set in advance inside the detection area X1 of the person detection system 1.

[0018] (2.2) Management device The management device 2 manages the detection results obtained by the detection unit 141 of the human detection system 1, which detect whether or not a person is present in the detection area X1. The management device 2 may be installed in the facility where the temperature acquisition unit 11 of the human detection system 1 is installed, or it may be installed in a location away from the above facility.

[0019] The management device 2 includes a control unit 21. The control unit 21 has a determination unit 211 and a region setting unit 212. The control unit 21 includes the processor of the computer system. The functions of the control unit 21 are realized by the processor executing a program recorded in the memory of the computer system. The program may be recorded in memory, provided via a telecommunication line such as the Internet, or provided on a non-temporary recording medium such as a memory card.

[0020] The determination unit 211 determines, based on the detection result of the detection unit 141 of the human detection system 1, whether or not person A1 has passed through the detection line Y1 which is set in advance inside the detection area X1.

[0021] The configuration for determining whether or not person A1 has passed the detection line Y1 in the determination unit 211 of this embodiment will be described in more detail below.

[0022] First, the determination unit 211 of this embodiment determines, based on the detection result of the detection unit 141, whether or not person A1 has left the detection area X1a (see Figure 2) of the temperature acquisition unit 11. Specifically, the determination unit 211 of this embodiment determines whether or not person A1 was present in the detection area X1a at the previous detection timing, and whether or not person A1 is no longer present in the detection area X1a at the current detection timing, as detected by the detection unit 141. Note that the detection area X1a is one of the two areas separated by the detection line Y1 in the detection area X1, as shown in Figure 2 (in the illustrated example, the left area).

[0023] Next, the determination unit 211 of this embodiment determines whether or not a person A1 has appeared in the detection area X1b (see Figure 2) of the temperature acquisition unit 11, based on the detection result of the detection unit 141. Specifically, the determination unit 211 of this embodiment determines whether or not a person A1 was not present in the detection area X1b at the previous detection timing, and whether or not the detection unit 141 has detected that a person A1 is present in the detection area X1b at the current detection timing. Note that the detection area X1b is a different area from the detection area X1a (in the illustrated example, the right-hand area) of the two areas separated by the detection line Y1 in the detection area X1, as shown in Figure 2.

[0024] Furthermore, the determination unit 211 of this embodiment determines that person A1 has passed the detection line Y1 if it determines that person A1 has left the detection area X1a and person A1 has appeared in the detection area X1b. On the other hand, the determination unit 211 of this embodiment determines that person A1 has not passed the detection line Y1 if it determines that person A1 has not left the detection area X1a or that person A1 has not appeared in the detection area X1b.

[0025] The area setting unit 212 sets the detection area X1 of the temperature acquisition unit 11 according to the installation height at which the temperature acquisition unit 11 is installed. The area setting unit 212 sets the detection area X1 within the maximum detection area X2 (see Figure 2) according to the installation height at which the temperature acquisition unit 11 is installed. The "maximum detection area X2" here refers to the largest area that the detection unit 141 can detect. As an example, the maximum detection area X2 is composed of 64 blocks arranged in an 8x8 grid. The size of each block may or may not be constant.

[0026] The comparative example's entry / exit detection system does not set the detection area of ​​the temperature acquisition unit according to its installation height. In the comparative example's entry / exit detection system, the temperature acquisition unit acquires information about the temperature in the same detection area as a thermal image, regardless of its installation height. As a result, in the comparative example's entry / exit detection system, if the installation height of the temperature acquisition unit differs from the expected height, the detection unit may perceive the movement speed of a person in the detection area as different from the movement speed that can be accurately determined (it may appear slower or faster). Therefore, the detection unit may not be able to accurately determine whether or not a person has passed the detection line.

[0027] On the other hand, in the entry / exit determination system 10 of this embodiment, the area setting unit 212 sets the detection area X1 of the temperature acquisition unit 11 according to the installation height at which the temperature acquisition unit 11 is installed. That is, the temperature acquisition unit 11 can acquire information about the temperature in an appropriate detection area X1 as a thermal image according to the installation height. As a result, the detection unit 141 can detect whether or not a person is present in the detection area X1 based on the thermal image acquired in an appropriate detection area X1 according to the installation height of the temperature acquisition unit 11. Therefore, when the installation height of the temperature acquisition unit 11 is different from the assumed height, the determination unit 211 can determine whether or not a person A1 has passed the detection line Y1 in a state where the movement speed of the person A1 present in the detection area X1 appears to be a movement speed that can be determined with high accuracy. In short, the entry / exit determination system 10 of this embodiment has the advantage of being able to determine with higher accuracy whether or not a person A1 has passed the detection line Y1 when the installation height of the temperature acquisition unit 11 is different from the assumed height.

[0028] The area setting unit 212 is configured such that the detection area X1 of the temperature acquisition unit 11 becomes narrower as the installation height increases. For example, if the installation height is the same as the expected height (specifically, if the installation height is 2400 mm), as shown in Figure 2, the area setting unit 212 sets 24 blocks arranged in a 6x4 grid within the maximum detection area X2 as the detection area X11. If the installation height is lower than the expected height (specifically, if the installation height is 2100 mm), as shown in Figure 3, the area setting unit 212 sets 48 blocks arranged in an 8x6 grid within the maximum detection area X2 as the detection area X12. If the installation height is higher than the expected height (specifically, if the installation height is 2700 mm), as shown in Figure 4, the area setting unit 212 sets 8 blocks arranged in a 4x2 grid within the maximum detection area X2 as the detection area X13.

[0029] (2.3) Human Detection System The human detection system 1, as shown in Figure 1, comprises a temperature acquisition unit 11, a filter 12, a height acquisition unit 13, and a control unit 14.

[0030] (Temperature acquisition unit) The temperature acquisition unit 11 acquires information about the temperature in the detection area X1 as a thermal image. In this embodiment, the temperature acquisition unit 11 acquires information about the temperature in the detection area X1 set by the area setting unit 212 within the maximum detection area X2 as a thermal image.

[0031] The temperature acquisition unit 11 is installed, for example, on the ceiling of the facility. That is, the maximum detection area X2 is, for example, part or all of a room in the facility. The facility is, for example, an indoor facility such as a house, office building, factory, mixed-use commercial facility, library, art museum, museum, amusement facility, airport, railway station, hotel, nursing home, and hospital. The facility may also be a moving object such as a ship, railway vehicle, or aircraft. Furthermore, the maximum detection area X2 may be an outdoor area. The maximum detection area X2 is composed of 64 blocks arranged in eight rows in the front-to-back direction and eight columns in the left-to-right direction along the horizontal plane when viewed from above (see Figure 2). However, the maximum detection area X2 is not limited to this arrangement.

[0032] The temperature acquisition unit 11 has a plurality of infrared sensors 111. Each of the plurality of infrared sensors 111 includes, for example, a thermopile. Each of the plurality of infrared sensors 111 receives infrared light emitted within its field of view. The plurality of infrared sensors 111 correspond one-to-one with a plurality of blocks that constitute the maximum detection area X2. Each of the plurality of infrared sensors 111 receives infrared light emitted from the corresponding area.

[0033] Each of the multiple infrared sensors 111 outputs a value corresponding to the infrared light reception intensity, that is, a value corresponding to the radiant temperature of its own field of view. The temperature acquisition unit 11 acquires (generates) a thermal image containing information on the values ​​corresponding to the radiant temperature of the field of view of each of the multiple infrared sensors 111 that correspond to each of the multiple blocks constituting the detection area X1. The thermal image is an image of pixels corresponding to the array of infrared sensors 111 that correspond to the areas constituting the detection area X1, and represents the radiant temperature of the detection area X1 with color.

[0034] Specifically, as shown in Figure 2, when 24 blocks arranged in a 6x4 grid are set as the detection area X11, the thermal image acquired by the temperature acquisition unit 11 is a 6x4 pixel image. Also, as shown in Figure 3, when 48 blocks arranged in an 8x6 grid are set as the detection area X12, the thermal image acquired by the temperature acquisition unit 11 is an 8x6 pixel image. Furthermore, as shown in Figure 4, when 8 blocks arranged in a 4x2 grid are set as the detection area X13, the thermal image acquired by the temperature acquisition unit 11 is a 4x2 pixel image.

[0035] (Filter) The filter 12 averages the thermal image acquired by the temperature acquisition unit 11. More specifically, the filter 12 averages the thermal image by blocking frequency components higher than the cutoff frequency in the thermal image acquired by the temperature acquisition unit 11. In other words, "averaging the thermal image" as used in this disclosure means mitigating sharp temperature changes in the thermal image. By averaging the thermal image with the filter 12, noise and other elements contained in the thermal image can be removed.

[0036] In filter 12, the range over which abrupt temperature changes in the thermal image are mitigated, that is, the range over which the thermal image is averaged, changes depending on the cutoff frequency value. The smaller the range over which the thermal image is averaged, the more even small changes in temperature in the thermal image can be mitigated.

[0037] Specifically, in filter 12, as the cutoff frequency increases, the range of frequency components to be removed narrows. Therefore, the higher the cutoff frequency, the more effectively filter 12 can mitigate only large temperature changes in the thermal image, that is, it can increase the range over which the thermal image is averaged. In this context, "increasing the range over which the thermal image is averaged" means increasing the averaging of the thermal image.

[0038] On the other hand, in filter 12, the range of frequency components removed widens as the cutoff frequency decreases. Therefore, the lower the cutoff frequency of filter 12, the more it can mitigate even small changes in temperature in the thermal image, that is, it can reduce the range over which the thermal image is averaged. "Reducing the range over which the thermal image is averaged" here means reducing the amount of thermal image averaging.

[0039] In filter 12, the cutoff frequency is changed according to the parameters set by the parameter setting unit 142, which will be described later. That is, filter 12 removes frequency components higher than the cutoff frequency changed according to the parameters set by the parameter setting unit 142 from the thermal image acquired by the temperature acquisition unit 11.

[0040] The filter 12 in this embodiment is an IIR (Infinite Impulse Response) filter. An IIR filter is a so-called infinite impulse response filter. An IIR filter is a filter that can change the frequency band that is passed through by setting the IIR filter coefficient within a predetermined range (for example, between 0.1 and 1). When the IIR filter coefficient is large, only low frequency bands are passed through, that is, the cutoff frequency decreases. On the other hand, when the IIR filter coefficient is small, high frequency bands are also more easily passed through, that is, the cutoff frequency increases.

[0041] In this embodiment, the parameter set by the parameter setting unit 142 is the IIR filter coefficient described above. This configuration has the advantage of eliminating the need to provide multiple filters 12 with different cutoff frequencies depending on the parameter set by the parameter setting unit 142. In other words, it has the advantage of simplifying the configuration of the filter 12.

[0042] (Height acquisition unit) The height acquisition unit 13 acquires the installation height, which is the height at which the temperature acquisition unit 11 is installed. The height acquisition unit 13 in the present embodiment acquires the installation height by receiving the installer's operation regarding the installation height when the temperature acquisition unit 11 is installed on the ceiling of the facility by the installer.

[0043] (Control unit) The control unit 14 includes a detection unit 141 and a parameter setting unit 142. The control unit 14 includes a processor of a computer system. The functions of the control unit 14 are realized by the processor executing a program recorded in the memory of the computer system. The program may be recorded in the memory, may be provided through an electrical communication line such as the Internet, or may be recorded and provided on a non-temporary recording medium such as a memory card.

[0044] The detection unit 141 detects whether a person A1 exists in the detection region X1 (see FIG. 2) based on the thermal image averaged by the filter 12. The detection unit 141 detects whether a person A1 exists in the detection region X1 at a preset predetermined interval (for example, an interval of 0.1 seconds). The detection unit 141 outputs the detection result to the management device 2.

[0045] The detection unit 141 in the present embodiment obtains the amount of change in the temperature value in each of the plurality of blocks constituting the detection region X1 based on the thermal image averaged by the filter 12. More specifically, the detection unit 141 in the present embodiment obtains, for each of the plurality of blocks constituting the detection region X1, the difference between the thermal image averaged by the filter 12 and the background thermal image stored in the storage unit 15 as the amount of change in the temperature value. The detection unit 141 in the present embodiment determines that a person A1 exists in the detection region X1 when there is a block in the plurality of blocks constituting the detection region X1 where the amount of change in the temperature value is equal to or greater than the threshold value. On the other hand, the detection unit 141 in the present embodiment determines that a person A1 does not exist in the detection region X1 when there is no block in the plurality of blocks constituting the detection region X1 where the amount of change in the temperature value is equal to or greater than the threshold value.

[0046] The detection unit 141 of the present embodiment detects whether or not person A1 exists in each of detection regions X1a and X1b in detection region X1.

[0047] That is, when there is a block in the plurality of blocks constituting detection region X1a where the amount of change in the temperature value is equal to or greater than the threshold value, the detection unit 141 of the present embodiment determines that person A1 exists in detection region X1a. On the other hand, when there is no block in the plurality of blocks constituting detection region X1a where the amount of change in the temperature value is equal to or greater than the threshold value, the detection unit 141 of the present embodiment determines that person A1 does not exist in detection region X1a.

[0048] Similarly, when there is a block in the plurality of blocks constituting detection region X1b where the amount of change in the temperature value is equal to or greater than the threshold value, the detection unit 141 of the present embodiment determines that person A1 exists in detection region X1b. On the other hand, when there is no block in the plurality of blocks constituting detection region X1b where the amount of change in the temperature value is equal to or greater than the threshold value, the detection unit 141 of the present embodiment determines that person A1 does not exist in detection region X1b.

[0049] The parameter setting unit 142 sets parameters regarding averaging by the filter 12 according to the installation height of the temperature acquisition unit 11 acquired by the height acquisition unit 13. The parameter setting unit 142 of the present embodiment sets the parameters of the filter 12 regarding the target range for which the filter 12 performs averaging according to the installation height of the temperature acquisition unit 11. In the present embodiment, the cut-off frequency of the filter 12 is changed according to the parameters of the filter 12 set by the parameter setting unit 142 according to the installation height of the temperature acquisition unit 11, and the target range for averaging the thermal image changes.

[0050] The person detection system of the comparative example does not set the parameters of the filter regarding the target range for which the filter performs averaging according to the installation height of the temperature acquisition unit. In the person detection system of the above comparative example, the filter performs averaging of the thermal image in the same target range regardless of the installation height of the temperature acquisition unit. As a result, in the person detection system of the comparative example, when the installation height of the temperature acquisition unit is different from the assumed height, there is a possibility that the detection unit cannot accurately detect whether or not a person exists in the detection region.

[0051] On the other hand, in the human detection system 1 of this embodiment, the parameter setting unit 142 sets the parameters of the filter 12 relating to the target range for which the filter 12 performs averaging, according to the installation height of the temperature acquisition unit 11. As a result, the filter 12 can average the thermal image in an appropriate target range according to the installation height of the temperature acquisition unit 11. As a result, the human detection system 1 of this embodiment has the advantage that even when the installation height of the temperature acquisition unit 11 is different from the assumed height, the detection unit 141 can accurately detect whether or not a person A1 is present in the detection area X1.

[0052] More specifically, the parameter setting unit 142 of this embodiment sets the parameters of the filter 12 such that the range over which the filter 12 performs averaging becomes smaller as the installation height of the temperature acquisition unit 11 increases. More specifically, the parameter setting unit 142 of this embodiment sets the parameters of the filter 12 such that the cutoff frequency becomes lower as the installation height of the temperature acquisition unit 11 increases. In this embodiment, since the filter 12 is an IIR filter, the parameter setting unit 142 sets the cutoff frequency lower by setting the IIR filter coefficient of the filter 12 to be larger as the installation height of the temperature acquisition unit 11 increases.

[0053] In the comparative example human detection system described above, when the installation height of the temperature acquisition unit is higher than the assumed height, the movement speed of the person from whom the temperature acquisition unit acquires temperature information appears slower than when the installation height of the temperature acquisition unit is the same as the assumed height. Therefore, in the comparative example human detection system, when the installation height of the temperature acquisition unit is higher than the assumed height, it may be difficult to distinguish between the temperature information of a person included in the thermal image and superimposed noise, etc. As a result, when the installation height of the temperature acquisition unit is higher than the assumed height, the detection unit may not be able to accurately detect whether or not a person is present in the detection area.

[0054] Furthermore, in the comparative example's human detection system, when the installation height of the temperature acquisition unit is lower than the assumed height, the movement speed of the person from whom the temperature acquisition unit acquires temperature information appears faster than the movement speed of the person from whom the temperature acquisition unit acquires temperature information when the installation height of the temperature acquisition unit is the same as the assumed height. For this reason, in the comparative example's human detection system, when the installation height of the temperature acquisition unit is lower than the assumed height, the detection unit may not be able to keep up with the movement speed of the person included in the thermal image. As a result, in the comparative example's human detection system, when the installation height of the temperature acquisition unit is lower than the assumed height, the detection unit may not be able to accurately detect whether or not a person is present in the detection area.

[0055] On the other hand, in the human detection system 1 of this embodiment, the parameter setting unit 142 sets the parameters of the filter 12 such that the range over which the filter 12 performs averaging becomes smaller as the installation height of the temperature acquisition unit 11 increases. Therefore, in the human detection system 1 of this embodiment, by having the filter 12 perform averaging, it is possible to suppress the difficulty in distinguishing between information about the temperature of person A1 included in the thermal image and superimposed noise, etc., when the installation height of the temperature acquisition unit 11 is higher than the assumed height. Furthermore, in the human detection system 1 of this embodiment, it is possible to suppress the inability of the detection unit 141 to follow the movement speed of person A1 included in the thermal image when the installation height of the temperature acquisition unit 11 is lower than the assumed height. As a result, the human detection system 1 of this embodiment has the advantage that the detection unit 141 can more accurately detect whether or not person A1 is present in the detection area X1.

[0056] (Memory Unit) The memory unit 15 includes a rewritable non-volatile memory, such as an EEPROM (Electrically Erasable Programmable Read-Only Memory). The memory unit 15 stores a thermal image as a background thermal image, which is acquired by the temperature acquisition unit 11 at a predetermined timing and averaged by the filter 12. The "predetermined timing" here refers to, for example, the timing when the human detection system 1 is activated.

[0057] (3) Operation (3.1) Entry / Exit Determination Method and Person Detection Method Here, an entry / exit determination method in which the entry / exit determination system 10 determines whether or not person A1 has entered or exited by passing through the detection line Y1, and a person detection method in which the person detection system 1 detects whether or not a person is present in the detection area X1 will be explained using Figure 5. Note that the flowchart shown in Figure 5 is merely an example of the above entry / exit determination method and person detection method relating to this disclosure, and the order of processing may be changed as appropriate, and processing may be added or omitted as appropriate.

[0058] The entry / exit determination method of the entry / exit determination system 10 includes, as shown in Figure 5, a height acquisition step S1, a region setting step S2, a temperature acquisition step S3, a parameter setting step S4, an averaging step S5, a detection step S6, and a determination step S7. The height acquisition step S1, temperature acquisition step S3, parameter setting step S4, averaging step S5, and detection step S6 in the above entry / exit determination method correspond to the person detection method of the person detection system 1.

[0059] In the height acquisition step S1, the height acquisition unit 13 acquires the installation height, which is the height at which the temperature acquisition unit 11 is installed. In the height acquisition step S1 of this embodiment, the height acquisition unit 13 acquires the installation height by receiving the installer's operation regarding the installation height. Then, in the area setting step S2, the area setting unit 212 of the management device 2 sets the detection area X1 of the temperature acquisition unit 11 within the maximum detection area X2 according to the installation height acquired by the height acquisition unit 13 in the height acquisition step S1. Subsequently, in the temperature acquisition step S3, the temperature acquisition unit 11 acquires information regarding the temperature in the detection area X1 as a thermal image. In the temperature acquisition step S3 of this embodiment, the temperature acquisition unit 11 acquires information regarding the temperature in the detection area X1 set by the area setting unit 212 within the maximum detection area X2 in the area setting step S2 as a thermal image.

[0060] In the parameter setting step S4, the parameter setting unit 142 sets parameters related to averaging by the filter 12 in the averaging step S5, according to the installation height of the temperature acquisition unit 11 acquired by the height acquisition unit 13 in the height acquisition step S1. In the parameter setting step S4 of this embodiment, the parameter setting unit 142 sets the parameters of the filter 12 related to the range over which the filter 12 performs averaging, according to the installation height of the temperature acquisition unit 11. More specifically, the parameter setting unit 142 sets the parameters of the filter 12 such that the range over which the filter 12 performs averaging becomes smaller the higher the installation height of the temperature acquisition unit 11. Then, in the averaging step S5, the filter 12 performs averaging of the thermal image acquired by the temperature acquisition unit 11 in the temperature acquisition step S3. In the averaging step S5 of this embodiment, the filter 12 removes frequency components higher than the cutoff frequency, which is changed according to the parameters set by the parameter setting unit 142 in the parameter setting step S4, from the thermal image acquired by the temperature acquisition unit 11 in the temperature acquisition step S3.

[0061] In detection step S6, the detection unit 141 detects whether or not a person A1 is present in the detection area X1 based on the thermal image that has been averaged by the filter 12 in averaging step S5. In detection step S6 of this embodiment, the detection unit 141 determines that a person A1 is present in the detection area X1 if there is a block among the multiple blocks constituting the detection area X1 in which the change in temperature value is greater than or equal to a threshold. On the other hand, in detection step S6 of this embodiment, the detection unit 141 determines that a person A1 is not present in the detection area X1 if there is no block among the multiple blocks constituting the detection area X1 in which the change in temperature value is greater than or equal to a threshold.

[0062] Subsequently, in the determination step S7, based on the detection result of the detection unit 141 of the human detection system 1 in the detection step S6, it is determined whether or not person A1 has passed through the detection line Y1 which is set in advance inside the detection area X1.

[0063] (3.2) Determination Step Here, the determination step S7 in Figure 5 will be explained in more detail using Figure 6. Note that the flowchart shown in Figure 6 is merely one example of the determination step S7 relating to this disclosure, and the order of processing may be changed as appropriate, and processing may be added or omitted as appropriate.

[0064] The determination unit 211 determines, based on the detection result of the detection unit 141 in detection step S6, whether or not person A1 has left the detection area X1a (see Figure 2) of the temperature acquisition unit 11 (step S71). Specifically, the determination unit 211 determines whether or not person A1 was present in the detection area X1a at the previous detection timing, and whether or not person A1 is absent from the detection area X1a at the current detection timing, as detected by the detection unit 141.

[0065] If the temperature acquisition unit 11 determines that person A1 has not left the detection area X1a (S71: No), the determination unit 211 determines that person A1 has not passed through the detection line Y1 (step S74).

[0066] On the other hand, if the temperature acquisition unit 11 determines that person A1 has left the detection area X1a (S71: Yes), the determination unit 211 determines, based on the detection result of the detection unit 141, whether or not person A1 has appeared in the detection area X1b of the temperature acquisition unit 11 (see Figure 2) (step S71). Specifically, the determination unit 211 determines whether or not person A1 was not present in the detection area X1b at the previous detection timing, and whether or not person A1 was present in the detection area X1b at the current detection timing, as detected by the detection unit 141.

[0067] If the temperature acquisition unit 11 determines that person A1 is not present in the detection area X1b (S72: No), the determination unit 211 determines that person A1 has not passed through the detection line Y1 (step S74).

[0068] On the other hand, if the temperature acquisition unit 11 determines that person A1 has appeared in the detection area X1b (S72: Yes), the determination unit 211 determines that person A1 has passed through the detection line Y1 (step S73).

[0069] (4) Effects The human detection system 1 according to this embodiment includes a temperature acquisition unit 11, a filter 12, a detection unit 141, a height acquisition unit 13, and a parameter setting unit 142. The temperature acquisition unit 11 acquires information about the temperature in the detection area X1 as a thermal image. The filter 12 averages the thermal image acquired by the temperature acquisition unit 11. The detection unit 141 detects whether or not a person is present in the detection area X1 based on the thermal image averaged by the filter 12. The height acquisition unit 13 acquires the installation height, which is the height at which the temperature acquisition unit 11 is installed. The parameter setting unit 142 sets parameters related to the averaging of the thermal image by the filter 12 according to the installation height acquired by the height acquisition unit 13. As a result, in the human detection system 1 of this embodiment, the filter 12 can perform thermal image averaging suitable for the installation height at which the temperature acquisition unit 11 is installed. Therefore, the detection unit 141 detects whether or not a person is present in the detection area X1 based on the thermal image that has been averaged to suit the installation height at which the temperature acquisition unit 11 is installed. In other words, the human detection system 1 of this embodiment has the advantage of being able to accurately detect whether or not a person is present, regardless of the installation height at which the temperature acquisition unit 11 is installed.

[0070] In the human detection system 1 according to this embodiment, the parameters of the filter 12 relating to the range to which the filter 12 performs averaging are set according to the installation height of the temperature acquisition unit 11. As a result, the filter 12 can average the thermal image within an appropriate range according to the installation height of the temperature acquisition unit 11. As a result, the human detection system 1 of this embodiment has the advantage that even when the installation height of the temperature acquisition unit 11 is different from the expected height, the detection unit 141 can accurately detect whether or not a person A1 is present in the detection area X1.

[0071] In the person detection system 1 according to this embodiment, the parameter setting unit 142 sets the parameters of the filter 12 such that the range over which the filter 12 performs averaging becomes smaller as the installation height of the temperature acquisition unit 11 increases. As a result, in the person detection system 1 of this embodiment, the averaging performed by the filter 12 can suppress the difficulty in distinguishing between information about the temperature of person A1 included in the thermal image and superimposed noise, etc., when the installation height of the temperature acquisition unit 11 is higher than the assumed height. Furthermore, in the person detection system 1 of this embodiment, the inability of the detection unit 141 to follow the movement speed of person A1 included in the thermal image can be suppressed when the installation height of the temperature acquisition unit 11 is lower than the assumed height. As a result, the person detection system 1 of this embodiment has the advantage that the detection unit 141 can more accurately detect whether or not person A1 is present in the detection area X1.

[0072] In the human detection system 1 according to this embodiment, the filter 12 is an IIR filter, and the parameter set by the parameter setting unit 142 is the IIR filter coefficient described above. This has the effect of eliminating the need to provide multiple filters 12 with different cutoff frequencies depending on the parameter set by the parameter setting unit 142. In other words, it has the advantage of simplifying the configuration of the filter 12.

[0073] The entry / exit determination system 10 according to this embodiment comprises a person detection system 1 and a determination unit 211. Based on the detection result of the detection unit 141 of the person detection system 1, the determination unit 211 determines whether or not a person A1 has passed through a detection line Y1 that is set in advance inside the detection area X1. As a result, the person detection system 1 of this embodiment has the advantage of being able to accurately determine whether or not a person A1 has passed through, regardless of the installation height at which the temperature acquisition unit 11 is installed.

[0074] The entry / exit determination system 10 according to this embodiment further includes a region setting unit 212 that sets the detection region X1 of the temperature acquisition unit 11 according to the installation height of the temperature acquisition unit 11. As a result, the temperature acquisition unit 11 can acquire information about the temperature in an appropriate detection region X1 as a thermal image according to the installation height. As a result, the detection unit 141 can detect whether or not a person is present in the detection region X1 based on the thermal image acquired in an appropriate detection region X1 according to the installation height of the temperature acquisition unit 11. Therefore, when the installation height of the temperature acquisition unit 11 is different from the assumed height, the determination unit 211 can determine whether or not a person A1 has passed the detection line Y1 while the movement speed of the person A1 present in the detection region X1 appears to be the same as a movement speed that can be determined with high accuracy. In short, the entry / exit determination system 10 of this embodiment has the advantage of being able to determine with higher accuracy whether or not a person A1 has passed the detection line Y1 when the installation height of the temperature acquisition unit 11 is different from the assumed height.

[0075] (5) Modifications The embodiments described above are merely one of many embodiments of the present disclosure. The embodiments described above can be modified in various ways depending on the design, etc., as long as the objectives of the present disclosure can be achieved. The following modifications may be implemented by combining them as appropriate. Components similar to those in the embodiments described above are denoted by the same reference numerals and their description is omitted. Furthermore, functions similar to those of the entry / exit determination system 10 and the person detection system 1 according to the embodiments described above may be embodied in a computer program or a non-temporary recording medium on which the program is recorded. A program according to one embodiment is a program that causes a computer system to execute the entry / exit determination method and the person detection method in the embodiments described above.

[0076] In the above-described embodiment, the height acquisition unit 13 acquires the installation height by receiving an operation from the installer regarding the installation height, which is the height at which the temperature acquisition unit 11 is installed. However, the height acquisition unit 13 may also estimate and acquire the installation height based on the area occupied by person A1 in the detection area X1 when the detection unit 141 detects person A1. Alternatively, the height acquisition unit 13 may measure and acquire the installation height using a laser beam or the like.

[0077] In the above-described embodiment, the determination unit 211 determines that person A1 has passed the detection line Y1 when it determines that person A1 has left the detection area X1a and person A1 has appeared in the detection area X1b. However, the configuration in which the determination unit 211 determines that person A1 has passed the detection line Y1 is not limited to the above configuration.

[0078] In the above-described embodiment, the detection unit 141 determines that a person A1 is present in the detection area X1 if there is a block in the plurality of blocks constituting the detection area X1 where the change in temperature value is greater than or equal to a threshold. However, the configuration in which the detection unit 141 determines that a person A1 is present in the detection area X1 is not limited to the above configuration.

[0079] (Summary) The first embodiment of the human detection system (1) comprises a temperature acquisition unit (11), a filter (12), a detection unit (141), a height acquisition unit (13), and a parameter setting unit (142). The temperature acquisition unit (11) acquires information about the temperature in the detection area (X1) as a thermal image. The filter (12) averages the thermal image. The detection unit (141) detects whether or not a person (A1) is present in the detection area (X1) based on the thermal image averaged by the filter (12). The height acquisition unit (13) acquires the installation height, which is the height at which the temperature acquisition unit (11) is installed. The parameter setting unit (142) sets parameters related to averaging by the filter (12) according to the installation height.

[0080] This embodiment has the advantage of being able to accurately detect whether or not a person (A1) is present, regardless of the height at which the temperature acquisition unit (11) is installed.

[0081] In the second embodiment of the human detection system (1), in the first embodiment, the parameter setting unit (142) sets parameters relating to the range over which the filter (12) performs averaging, according to the installation height.

[0082] According to this embodiment, the filter (12) has the advantage of being able to average thermal images within an appropriate target range depending on the installation height of the temperature acquisition unit (11).

[0083] In the third embodiment of the human detection system (1), in the second embodiment, the parameter setting unit (142) sets the parameters such that the target range becomes smaller as the installation height increases.

[0084] This embodiment has the advantage of being able to detect with greater accuracy whether or not a person (A1) is present in the detection area (X1).

[0085] In the fourth embodiment of the human detection system (1), in any of the first to third embodiments, the filter (12) is an IIR filter (12). The parameter is the IIR filter (12) coefficient.

[0086] This embodiment has the advantage of simplifying the configuration of the filter (12).

[0087] The fifth embodiment of the entry / exit determination system (10) comprises a person detection system (1) according to any of the first to fourth embodiments and a determination unit (211). The determination unit (211) determines, based on the detection result of the detection unit (141), whether or not a person (A1) has passed through a detection line (Y1) that is set in advance inside the detection area (X1).

[0088] This embodiment has the advantage of accurately determining whether or not a person (A1) has passed the detection line (Y1), regardless of the installation height at which the temperature acquisition unit (11) is installed.

[0089] The sixth embodiment of the entry / exit determination system (10) further includes, in the fifth embodiment, an area setting unit (212) for setting a detection area (X1) according to the installation height.

[0090] According to this embodiment, there is an advantage in that it is possible to determine with greater accuracy whether or not a person (A1) has passed the detection line (Y1) when the installation height of the temperature acquisition unit (11) is different from the expected height.

[0091] The seventh embodiment of the human detection method is used in a human detection system (1) comprising a temperature acquisition unit (11), a filter (12), a detection unit (141), a height acquisition unit (13), and a parameter setting unit (142). The temperature acquisition unit (11) acquires information regarding the temperature in the detection area (X1) as a thermal image. The filter (12) performs averaging of the thermal image. The detection unit (141) detects whether or not a person (A1) is present in the detection area (X1) based on the thermal image averaged by the filter (12). The height acquisition unit (13) acquires the installation height, which is the height at which the temperature acquisition unit (11) is installed. The parameter setting unit (142) sets parameters related to averaging by the filter (12) according to the installation height.

[0092] According to this embodiment, there is an advantage in that it is possible to accurately detect whether or not a person (A1) is present, regardless of the height at which the temperature acquisition unit (11) is installed, without using a dedicated person detection system (1).

[0093] The program of the eighth aspect is a program that causes a computer system to execute the person detection method of the seventh aspect.

[0094] According to this embodiment, there is an advantage in that it is possible to accurately detect whether or not a person (A1) is present, regardless of the height at which the temperature acquisition unit (11) is installed, without using a dedicated person detection system (1).

[0095] 10 Entry / Exit Judgment System 1 Person Detection System 11 Temperature Acquisition Unit 12 Filter 13 Height Acquisition Unit 141 Detection Unit 142 Parameter Setting Unit 211 Judgment Unit 212 Area Setting Unit S1 Height Acquisition Step S3 Temperature Acquisition Step S4 Parameter Setting Step S5 Averaging Step S6 Detection Step A1 Person X1 Detection Area Y1 Detection Line

Claims

1. A human detection system comprising: a temperature acquisition unit that acquires information regarding the temperature in a detection area as a thermal image; a filter that averages the thermal image; a detection unit that detects whether or not a person is present in the detection area based on the thermal image averaged by the filter; a height acquisition unit that acquires the installation height, which is the height at which the temperature acquisition unit is installed; and a parameter setting unit that sets parameters related to the averaging by the filter according to the installation height.

2. The person detection system according to claim 1, wherein the parameter setting unit sets the parameters relating to the range to which the filter performs averaging, according to the installation height.

3. The person detection system according to claim 2, wherein the parameter setting unit sets the parameters such that the target range becomes smaller as the installation height increases.

4. The human detection system according to claim 1, wherein the filter is an IIR filter, and the parameter is an IIR filter coefficient.

5. An entry / exit determination system comprising: a person detection system according to any one of claims 1 to 4; and a determination unit that determines, based on the detection result of the detection unit, whether or not the person has passed through a detection line that is set in advance inside the detection area.

6. The entry / exit determination system according to claim 5, further comprising a region setting unit for setting the detection region according to the installation height.

7. A person detection method used in a person detection system comprising a temperature acquisition unit, a filter, a detection unit, a height acquisition unit, and a parameter setting unit, wherein the temperature acquisition unit acquires information regarding the temperature in a detection area as a thermal image; the filter averages the thermal image; the detection unit detects whether or not a person is present in the detection area based on the thermal image averaged by the filter; the height acquisition unit acquires the installation height, which is the height at which the temperature acquisition unit is installed; and the parameter setting unit sets parameters related to the averaging by the filter according to the installation height.

8. A program for causing a computer system to execute the person detection method described in claim 7.

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