Passive human body detection method, device, equipment and medium

Abstract

The present invention belongs to the technical field of human body detection, and particularly relates to a passive human body detection method, device, equipment and medium, for solving the problem that the conventional human body detection technology is easily interfered with and has low detection accuracy. The method includes: acquiring infrared thermal radiation signals in an environment to acquire the temperature of an object; transmitting electromagnetic waves into the environment and acquiring reflected echo signals; determining the position of the object in the environment based on the echo signals; matching a threshold range based on the position of the object; and comparing the temperature of the object with the threshold range to determine human body detection information in the environment. The present invention combines electromagnetic detection and thermography to detect whether a person exists in the current environment, and can effectively filter out interference signals, greatly improving the accuracy and sensitivity of detecting the presence of a human body.

Description

[Technical field]

[0001] The present invention relates to the technical field of human body detection, and more particularly to a method, device, instrument and medium for passive human body detection. [Background technology]

[0002] Traditionally, in the field of human body detection, the main technologies include PIR sensors, millimeter wave radar sensors, and RGB cameras.

[0003] The disadvantage of the PIR sensor is that it is easily affected by various heat and light sources, and is greatly affected by the environmental temperature. In addition, passive infrared rays have poor penetration power and are difficult to receive by the probe, so it cannot detect the presence of a stationary person and cannot identify the state of movement of a person.

[0004] Millimeter wave radar sensors have high resolution and interference resistance, and are highly accurate in detecting moving or slightly moving targets. The downside is that they are prone to false positives when detecting human bodies, and they can easily identify other moving objects as people. In addition, imaging using a high-precision radar is required to identify the movement state of a person.

[0005] Human body detection technology that combines RGB cameras and machine learning is prone to violating privacy and has limited application scenarios. Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above, the human body detection technology in the prior art has problems such as being easily interfered with and having a low detection accuracy, which need to be solved. [Means for solving the problem]

[0007] In view of the above analysis, the embodiment of the present invention aims to provide a passive human body detection method to solve the problem that the conventional human body detection technology is easily interfered with and has a low detection accuracy. The aspects provided by the embodiment of the present invention include: acquiring an infrared thermal radiation signal in the environment to obtain a temperature of the subject; Emitting electromagnetic waves into the environment and acquiring reflected echo signals; determining a position of the subject in the environment based on the echo signals; and matching a threshold range based on a position of the subject; and comparing a temperature of the subject to the threshold range to determine human body detection information in the environment.

[0008] In some embodiments, the infrared thermal radiation signal is acquired by a thermography device and converted into a thermal image.

[0009] In some embodiments, the method further includes determining a distance between the object and an infrared thermal radiation signal detection source based on the echo signal, and determining the threshold range according to a temperature indication range model based on the distance.

[0010] In some embodiments, the threshold range matches a temperature indication range that the body would show in the thermal image at the distance.

[0011] In some embodiments, if the temperature of the subject is within the threshold range, a motion posture of the subject is determined by a posture identification model based on a shape of the subject in the thermal image.

[0012] In some embodiments, motion parameter information of the subject in the motion posture is determined based on the echo signals and the thermal image.

[0013] In some embodiments, the human body detection information includes one or a combination of the following: presence or absence of a human body, a position of a human body, a height of a human body, a posture of a human body, or a motion parameter information.

[0014] The present invention further provides a passive human body detection device, a temperature detection module for acquiring infrared thermal radiation signals in the environment so as to acquire a temperature of the subject; an electromagnetic wave detection module that emits electromagnetic waves into the environment and acquires reflected echo signals; a location detection module that determines a location of the subject in the environment based on the echo signals; a threshold matching module for matching a threshold range based on the position of the subject; and a human body detection module that compares a temperature of the subject with the threshold range to determine human body detection information in the environment.

[0015] The present invention further provides an electronic device including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the passive human body detection method described in any one of the above embodiments is realized.

[0016] The present invention further provides a computer-readable storage medium, on which a computer program is stored, and which, when executed by a processor, realizes the passive human body detection method described in any one of the above embodiments. Effect of the Invention

[0017] The human body detection system provided by the present invention detects whether a person exists in the current environment by combining electromagnetic detection and thermography, and can effectively filter out interference signals, greatly improving the accuracy and sensitivity of detecting the presence of a human body. It can also identify the number of people and their movement state by referring to the spatial position and speed of the target by the electromagnetic detection and the temperature and pixel information by the thermography.

[0018] In addition, embodiments of the present invention can also avoid interference with detection due to changes in temperature indication caused by the distance between the human body and the thermography device by determining the distance between the subject and the source of the infrared thermal radiation signal and adjusting the threshold range for making a temperature judgment on the subject based on the distance. [Brief description of the drawings]

[0019] In order to more clearly explain the embodiments or aspects of the prior art of the present specification, the following briefly introduces the drawings that need to be used in the description of the embodiments or prior art. The drawings in the following description are only some embodiments described in the embodiments of the present specification, and it is obvious to those of ordinary skill in the art that other drawings can be obtained based on these drawings.

[0020] [Figure 1] FIG. 1 is a schematic flow chart of a passive human body detection method provided by the present invention. [Diagram 2] FIG. 2 is a schematic diagram of a passive human body detection device provided by the present invention. [Diagram 3] FIG. 3 is a schematic diagram of an electronic device provided by the present invention. [Figure 4] FIG. 4 is a schematic diagram of a human body detection system provided according to an embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic diagram of a preferred embodiment of a human body detection system provided by the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In order to make the objectives, aspects and advantages of the embodiments of the present invention clearer, the following will provide a clear and complete description of the aspects of the embodiments of the present invention with reference to the drawings in the embodiments of the present invention, and it is clear that the described embodiments are only a part of the embodiments of the present invention, and are not all of the embodiments. In addition, if there is no conflict, the embodiments of the present invention and the features in the embodiments can be combined, separated, exchanged and / or rearranged with each other. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0022] In the drawings, dimensions and relative dimensions of parts may be exaggerated for purposes of clarity and / or representation. Example embodiments may alternatively be practiced, where specific process steps may be performed in a different order than described. For example, two processes described as sequential may be performed substantially simultaneously, or may be performed in the reverse order to that described. Also, like reference numbers refer to like parts.

[0023] When a component is referred to as "located" or "on" or "connected" or "coupled" to another component, the component may be directly located on the other component, directly connected or coupled to the other component, or there may be intermediate components present. However, when a component is referred to as "located" or "directly connected" or "directly coupled" to another component, there are no intermediate components present. Thus, the term "connection" can mean a physical connection, an electrical connection, etc., and intermediate components may or may not be present.

[0024] For purposes of descriptiveness, the present invention may use relative spatial terms for parts, such as "top", "bottom", "below", "lower than", "under", "down", "above", "up", "on", "high", etc., to describe the relationship of one part to another part shown in the drawings.

[0025] The terms used herein are for the purpose of describing specific embodiments and are not intended to be limiting. As used herein, the singular forms "a" and "the" are intended to include the plural, unless the context clearly indicates otherwise. Additionally, when the terms "comprise" and / or "include" and variations thereof are used herein, they refer to the presence of a stated feature, whole, step, operation, part, component, and / or group thereof, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, parts, components, and / or groups thereof. It should be further noted that the terms "essentially," "about," and other similar terms used herein are not used as terms of degree, but are used as terms of approximation, and as such, they are used to interpret the inherent variation in measurements, calculations, and / or values ​​provided that would be recognized by one of ordinary skill in the art.

[0026] The present invention provides a specific embodiment, as shown in FIG. 1, which discloses a passive human body detection method to solve the problem that the conventional human body detection technology is easily interfered with and has a low detection accuracy. The embodiment provides the following: acquiring an infrared thermal radiation signal in the environment to obtain a temperature of the subject; Emitting electromagnetic waves into the environment and acquiring reflected echo signals; determining a position of the subject in the environment based on the echo signals; and matching a threshold range based on a position of the subject; and comparing a temperature of the subject to the threshold range to determine human body detection information in the environment.

[0027] Preferably, the infrared thermal radiation signal is acquired by a thermographic device and converted into a thermal image. Specifically, a thermographic device may be installed to capture the infrared thermal radiation signal in the environment and form a thermal image. On the other hand, an electromagnetic wave detector may emit electromagnetic waves and receive echo signals, and based on the echo signals, spatial information such as the position, distance, shape, and height of an object, and motion information such as the motion speed and acceleration can be determined.

[0028] Specifically, in this embodiment, by analyzing the echo signal of the electromagnetic wave emitted by the electromagnetic wave detector, it is possible to determine the position where an "obstacle", that is, the subject, exists in the environment, that is, to detect the position area where a human body may appear in the target environment. By using this position area, a temperature comparison is made in the thermal image formed by the infrared thermal radiation signal. If the comparison is as expected, it is initially considered that a human body exists in the position area, and further confirmation is carried out. Among them, the distance between the human body and the detection source of the infrared thermal radiation signal, for example, a thermographic device, has a very large impact on the infrared thermal radiation signal. Therefore, the body temperature display value of the human body detected by the thermographic device tends to drop as the distance increases. At the same time, the distance and orientation of the human body have a significant impact on the temperature distribution of the human body in the thermal image. Therefore, in this embodiment, first, a threshold range is matched based on the position of the subject, and the threshold range is made to match the range of the temperature shown by the human body in the thermal image at a specific position. This reduces the adverse effects caused by the characteristics of the thermographic device and makes the detection more accurate.

[0029] After determining the threshold range, the temperature corresponding to the area where the subject is located in the thermal image is compared with the threshold range. In some embodiments, the ratio occupied by the portion between the upper and lower limits of the threshold range of the area temperature is determined to determine whether the subject is as expected in the comparison. If most of the area temperature of the subject is within the threshold range, it is initially considered that the subject is a human body, and further information analysis is performed on it.

[0030] In some embodiments, the human body detection information includes one or a combination of the following: presence or absence of a human body, position, height, posture, or motion parameter information of the human body. The human body detection information may be understood as a comprehensive information including presence or absence of a human body, posture of the human body, scene in which the human body is located, motion state, speed, acceleration, etc. Among them, the electromagnetic wave detector can measure information such as the position, speed, acceleration, and height of the human body. The thermal image formed by the infrared thermal radiation signal can determine the posture of the human body, such as lying, standing, sitting, etc.

[0031] Preferably, the method further includes determining a distance between the object and a detection source of an infrared thermal radiation signal based on the echo signal, and determining the threshold range according to a temperature display range model based on the distance, the threshold range matching the temperature display range that the human body shows in the thermal image at the distance. This embodiment can mainly focus on the effect of the object's distance on the temperature display in the thermal image.

[0032] In some embodiments, adjusting the threshold range based on the distance includes determining the threshold range by the temperature display range determination model based on the distance, wherein the temperature display range determination model is trained by displayed temperatures in thermal images formed of a plurality of human bodies at different distances from the thermography device, and the temperature display range determination model is for outputting a temperature display range for a human body at a particular distance based on an input distance.

[0033] Preferably, when the temperature of the subject is within the threshold range, a motion posture of the subject is determined based on the shape of the subject in the thermal image by a posture identification model, the posture identification model being trained by thermal images formed in different human body postures.

[0034] In some embodiments, motion parameter information of the subject in the motion posture may be determined based on the echo signals and the thermal image.

[0035] The present invention further provides a passive human body detection device, as shown in FIG. a thermal radiation acquisition module for acquiring infrared thermal radiation signals in an environment; an electromagnetic wave detection module that emits electromagnetic waves into the environment and acquires reflected echo signals; a location detection module that determines a location of the subject in the environment based on the echo signals; and a human body detection module for determining whether a temperature of the subject is within a threshold range based on a position of the subject and the infrared thermal radiation signal, so as to determine human body detection information in the environment.

[0036] The present invention further provides an electronic device, as shown in FIG. 3, including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the passive human body detection method described in any one of the above embodiments is realized.

[0037] The present invention further provides a computer-readable storage medium, on which a computer program is stored, and which, when executed by a processor, realizes the passive human body detection method described in any one of the above embodiments.

[0038] The present invention provides another specific embodiment, and discloses a human body detection system as shown in FIG. 4, which includes a thermography device 1 for acquiring a thermal image of an environment, an electromagnetic wave detector 2 for transmitting electromagnetic waves to the environment and acquiring a reflected echo signal, a position identification module 3 communicatively connected to the electromagnetic wave detector 2 and arranged to determine a position of an object 8 based on the echo signal, and a processing module 4 communicatively connected to the thermography device 1 and the position identification module 3, respectively, arranged to determine whether the temperature of the position is within a threshold range based on the thermal image, and if so, to initially determine that a human body may be detected. Although omitted here, it can be further confirmed later by more accurate technical means. The threshold range may be set based on empirical data of the temperature of a human body shown in a thermal image, which has an upper limit and a lower limit, and when the temperature shown in the thermal image is detected to be between the upper limit and the lower limit, the temperature is considered to be within the threshold range.

[0039] Among them, the position identified by the position identification module 3 refers to the position of the object 8 in the electromagnetic wave detection area, and for example, when the electromagnetic wave detection result is displayed as a plane figure, the position refers to the display of the position of the object 8 in the plane figure, which may correspond to the position in the thermal image. Or, for example, when the electromagnetic wave detection result is displayed as a sector area, the position may refer to the object 8 being in a certain angular direction.

[0040] Specifically, the electromagnetic wave detector 2 may emit electromagnetic waves to the environment or target area and receive the reflected echo signals. The location identification module 3 may be an analysis module built into the electromagnetic wave detector 2, and may be understood as a signal analysis module other than the electromagnetic wave generator and receiver of the electromagnetic wave detector 2. By analyzing the echo signals, it is possible to obtain whether or not the object 8 is present in the detected environment or target area, and the object 8 refers to an object that may be an electromagnetic wave "obstacle", including a human body, a small animal, a small building, etc., and the location identification module 3 can obtain the positional space information of each object 8 by analyzing the echo signals. From this, it can be seen that if a human body is detected only by the electromagnetic wave detector 2, it is easier to identify other objects 8 as human bodies.

[0041] In addition, this embodiment further detects the human body based on the thermal image or temperature matrix acquired by the thermography device 1, whereas if only the thermography device 1 is used for detection, it is susceptible to interference from other heat sources and light sources, and is greatly affected by the environmental temperature.

[0042] In this embodiment, the electromagnetic detector 2 performs electromagnetic detection, and the location identification module can obtain whether there is a suspected human body 8 in the target area and determine multiple candidate targets. Then, the thermography device 1 obtains the thermal image or temperature matrix to judge the temperature of the location where the object 8 is located, and a threshold is set according to the temperature display in the thermal image of the human body. If the temperature in the thermal image of the location where the object 8 is located is within the threshold range, it is initially detected that there may be a human body in that location. Then, the location identification module can determine whether there are several human bodies in the target area and their respective locations. The interference signals can be effectively filtered, and the accuracy and sensitivity of detecting the presence of a human body can be greatly improved.

[0043] Preferably, as shown in FIG. 5, in some embodiments, the apparatus further includes a distance detection module 5 communicatively connected to the electromagnetic wave detector 2 for determining the distance of the object 8 based on the echo signal, and an orientation detection module 6 communicatively connected to the electromagnetic wave detector 2 for determining the orientation of the object 8 based on the echo signal. The distance of the human body has a very large effect on the infrared thermal radiation signal, and the human body temperature display value detected by the thermography device 1 tends to drop with increasing distance. At the same time, the distance and orientation of the human body have a significant effect on the temperature distribution of the human body in the thermal image. Therefore, the distance and orientation of the object 8 are determined by the distance detection module 5 and the orientation detection module 6, and the processing module 4 further includes a threshold determination unit 41, which changes the threshold range based on the distance of the object 8 and adjusts the upper and lower temperature values. The interference of the distance between the human body and the thermography device 1 with the temperature display change can be avoided.

[0044] By installing the threshold determination unit 41, the accuracy of human body detection can be improved, while if only a fixed threshold is installed, when a human body is located at different distances from the thermography device 1, the influence of distance on the temperature measurement value will be such that if the lower limit of the threshold is too low, non-human objects will be easily identified as human bodies, and if the lower limit of the threshold is too high, a human body at a distant distance will be easily identified as not human, resulting in inaccurate detection. Also, by adjusting the threshold with respect to the distance of the subject 8, confusion between a human body and other living organisms can be avoided, for example, at the same distance, a small animal will have a lower body temperature than a human body, and its body temperature display will not fall within the threshold range set at that distance, and will not be identified as a human body.

[0045] Preferably, the thermography device 1 includes an infrared thermography sensor, and the electromagnetic wave detector 2 includes a millimeter wave radar sensor, the frequency of which is in the 5.8Ghz, 24Ghz, 60Ghz or UWB frequency range.

[0046] It is preferable that the detection ranges of the thermography device 1 and the electromagnetic wave detector 2 have an overlapping area, and preferably the detection ranges of both should be the same, for example, the angles of the lens and the electromagnetic wave generator should be the same and have a common starting point in order to perform information fusion or comparison between the electromagnetic wave detection results and the thermal image.

[0047] In some embodiments, as shown in FIG. 5, the apparatus further includes a motion state module 7 communicatively connected to the electromagnetic wave detector 2 for determining the speed of the object 8 based on the echo information. Preferably, the motion state module 7 is further communicatively connected to the thermography device 1. In this embodiment, the motion state module 7 may directly determine the motion parameters of a target based on the echo information, or may obtain the motion parameters of the target through dynamic analysis of a thermal image. However, when the thermal image or electromagnetic wave method is adopted alone, the motion analysis of multiple targets will be interfered by the shielding of the target. In this embodiment, the motion state module 7 may further determine the speed of the object 8 by referring to the echo information and the changes in the thermal image, and may analyze the motion state of each of multiple targets by referring to the thermal image and the echo information.

[0048] In addition, in some embodiments, the human body detection system provided by the present invention further includes an RGB camera or an IPR sensor, and different types of detection data are obtained by multiple sensors, and the trained model can judge the human body state based on the detection data, and identify a person's motion state, such as standing still, running, falling, lying down, etc., and a scene state, such as sleeping, watching a movie, looking at a mobile phone, etc.

[0049] Those skilled in the art should further understand that the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be realized by electronic hardware, computer software, or a combination of both, and in the above description, the configurations and steps of each example are generally described by function in order to clearly describe the compatibility of hardware and software. Whether these functions are performed in hardware or software mode depends on the specific application and design constraints of the embodiment. Those skilled in the art can realize the described functions using different methods for each specific application, however, this realization should not be considered to go beyond the scope of the present invention.

[0050] The steps of the method or algorithm described in connection with the embodiments disclosed herein may be implemented in hardware, or in software modules executed by a processor, or in a combination of both. The software modules may be located in a random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. The calculation, transmission, and control methods involved in the invention are all within the prior art, and the implementation of the invention does not depend on the computer program itself.

[0051] The specific embodiments described above are intended to explain the objectives, aspects and beneficial effects of the present invention in more detail. It should be understood that the above-described embodiments are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are all included in the scope of protection of the present invention. [Explanation of symbols]

[0052] 1. Thermography equipment 2 - Electromagnetic wave detector 3 – Location Identification Module 4. Processing Module 41 - Threshold determination unit 5. Distance detection module 6 – Orientation detection module 7. Movement state module

Claims

1. A passive human body detection method, comprising: acquiring an infrared thermal radiation signal in the environment to obtain a temperature of the subject; Emitting electromagnetic waves into the environment and acquiring reflected echo signals; determining a position of the subject in the environment based on the echo signals; and matching a threshold range based on a position of the subject; and comparing a temperature of the subject with the threshold range to determine human body detection information in the environment.

2. 2. The passive human body detection method according to claim 1, wherein the infrared thermal radiation signal is acquired by a thermography device and converted into a thermal image.

3. 3. The passive human body detection method of claim 2, further comprising: determining a distance between the object and an infrared thermal radiation signal detection source based on the echo signal; and determining the threshold range by a temperature display range model based on the distance.

4. 4. The method of claim 3, wherein the threshold range matches a temperature indication range that the human body will show in the thermal image at the distance.

5. The passive human body detection method according to claim 3, characterized in that when the temperature of the subject is within the threshold range, the motion posture of the subject is determined by a posture identification model based on the shape of the subject in the thermal image.

6. The passive human body detection method according to claim 5, further comprising determining motion parameter information of the subject in the motion posture based on the echo signal and the thermal image.

7. The passive human body detection method according to claim 1 , wherein the human body detection information includes one or a combination of multiple types of information on the presence or absence of a human body, the position, height, posture, or motion parameters of the human body.

8. A passive human body detection device, comprising: a temperature detection module for acquiring infrared thermal radiation signals in the environment so as to acquire a temperature of the subject; an electromagnetic wave detection module that emits electromagnetic waves into the environment and acquires reflected echo signals; a location detection module that determines a location of the subject in the environment based on the echo signals; a threshold matching module for matching a threshold range based on the position of the subject; a human body detection module that compares a temperature of the subject with the threshold range to determine human body detection information in the environment.

9. 8. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, and wherein the electronic device realizes the passive human body detection method according to any one of claims 1 to 7 when the computer program is executed by the processor.

10. 8. A computer-readable storage medium having a computer program stored thereon, the computer program implementing the passive human body detection method according to any one of claims 1 to 7 when executed by a processor.

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