KR20220160208A - Method and apparatus for detecting temperature of fever detection system using thermal image camera - Google Patents

Abstract

Provided is a temperature sensing method of a fever detection system using a thermal imaging camera. The temperature sensing method comprises the following steps of: obtaining a temperature distribution image of a measurement target photographed by a thermal imaging camera; measuring a temperature of the measurement target based on the temperature distribution image; determining a temperature compensation value according to a change in an external environment by using the measured temperature of the measurement target; and correcting the measured temperature of the measurement target by using the temperature compensation value.

Description

Method and apparatus for detecting temperature of a fever detection system using a thermal imaging camera

The present invention relates to a temperature sensing method and apparatus of a fever detection system using a thermal imaging camera, and more particularly, to a temperature sensing method and apparatus capable of consistently and accurately measuring body temperature regardless of environmental temperature changes without a separate hardware device requiring additional cost. It relates to a temperature sensing method and device for a fever detection system using an image camera.

A thermal imaging camera (Bolometer) detects radiated heat and measures the temperature by identifying the surface temperature of an object or the skin temperature of a person.

These thermal imaging cameras (bolometers) frequently generate measurement temperature deviations depending on the environment and ambient temperature changes of the installation site. Therefore, it is difficult to ensure accurate measurement when a thermal imaging camera is used alone.

In general, in order to obtain a more accurate thermal image measurement value, a thermal imaging camera uses a separate device capable of measuring a reference temperature, such as a black body or an external temperature sensor, to correct the measured temperature.

However, such a separate device requires additional cost, and in the case of a black body, it is expensive and difficult to install.

The problem to be solved by the present invention is to provide a temperature sensing method and device of a fever detection system using a thermal imaging camera that can consistently and accurately measure body temperature regardless of environmental temperature changes without a separate hardware device requiring additional cost.

According to one embodiment of the present invention, a temperature sensing method of a fever detection system using a thermal imaging camera is provided. The temperature sensing method includes acquiring a temperature distribution image of a measurement target captured by the thermal imaging camera, measuring the temperature of the measurement target based on the temperature distribution image, and using the measured temperature of the measurement target to measure the external environment. Determining a temperature compensation value according to the change, and correcting the measured temperature of the measurement target using the temperature compensation value.

The step of determining the temperature compensation value is a step of extracting a past background temperature representing a representative value of measured temperatures of accumulated past measurement objects, updating the background temperature using the measured temperature of the measurement object and the past background temperature. and determining the temperature compensation value from a difference between a preset reference temperature and the background temperature.

The updating may include removing noise from the measured temperature of the measurement object and the past background temperature.

The updating may include updating the background temperature with an average value of the measured temperature of the measurement object and the past background temperature.

According to another embodiment of the present invention, a temperature sensing device of a fever detection system using a thermal imaging camera is provided. The temperature sensing device includes a receiving unit that receives a temperature distribution image of a measurement target from a thermal imaging camera, a temperature measurement unit that measures the temperature of the measurement target from the temperature distribution image, extracts a past background temperature of the measurement target, and the measurement target. A compensation determination unit for determining a temperature compensation value according to a change in the external environment using the measured temperature of the past and the past background temperature of the past measurement object, and a temperature for correcting the measured temperature of the measurement object using the temperature compensation value. includes a correction unit.

The compensation determiner may update the background temperature using the measured temperature of the measurement object and the past background temperature of the past measurement object, and calculate the temperature compensation value from a difference between a preset reference temperature and the background temperature.

The compensation determination unit may extract a representative value of the measured temperatures of the past measurement objects as the past background temperature.

The compensation determiner may update the background temperature as an average value of the measured temperature of the measurement object and the past background temperature.

The compensation determination unit may include a filter for removing noise from the measured temperature of the measurement object and the past background temperature of the measurement object.

The filter may include a median filter.

According to an embodiment of the present invention, it is possible to improve body temperature error values due to environmental temperature changes or deviations between samples, and body temperature can be measured consistently and accurately regardless of environmental temperature changes without additional hardware equipment requiring additional cost. .

1 is a diagram illustrating a fever detection system using a thermal imaging camera according to an embodiment of the present invention.
FIG. 2 is a flowchart illustrating a method of sensing temperature in the temperature sensor shown in FIG. 1 .
3 is a diagram illustrating a method of determining a temperature compensation value according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating an example of the noise removal method shown in FIG. 3 .
FIG. 5 is a view showing the temperature sensor shown in FIG. 1 .
6 is a diagram illustrating a temperature sensing device according to another embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification and claims, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

Now, a temperature sensing method and apparatus of a fever detection system using a thermal imaging camera according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a fever detection system using a thermal imaging camera according to an embodiment of the present invention.

Referring to FIG. 1 , a fever detection system 100 includes a thermal imaging camera 110 and a temperature sensor 120 .

The thermal imaging camera 110 is a camera that measures a temperature (heat) distribution and can accurately measure this temperature difference as well as generate an image based on a temperature difference.

In the embodiment of the present invention, it is described that the thermal imaging camera 110 is used to measure the body temperature of a person, that is, a person to be measured, but the same can be applied to measuring the temperature of an object. In the case of measuring the temperature of an object, the term "body temperature" described below may be used instead of the term "temperature".

The thermal imaging camera 110 captures a temperature distribution image of the subject to be measured and transmits the temperature distribution image to the temperature sensor 120 .

The temperature sensor 120 calculates the body temperature of the measurement subject based on the temperature distribution image transmitted from the thermal imaging camera 110 . In addition, the calculated body temperature result is output according to the calculated body temperature of the subject to be measured.

When measuring body temperature, the thermal imaging camera 110 sensitively changes the measured body temperature according to changes in ambient temperature. Therefore, when body temperature is measured using the thermal imaging camera 110, the measured temperature is corrected using a separate device capable of measuring the reference temperature, for example, a black body or an external temperature sensor.

However, additional costs are incurred due to the use of a separate device, and in the case of a black body, it is expensive and difficult to install.

Therefore, the temperature sensor 120 according to the embodiment of the present invention corrects the body temperature of the subject to be measured through the thermal imaging camera 110 without using a separate device.

FIG. 2 is a flowchart illustrating a method of sensing temperature in the temperature sensor shown in FIG. 1 .

Referring to FIG. 2 , when the temperature sensor 120 receives the temperature distribution image transmitted from the thermal imaging camera 110 (S210), it measures the body temperature of the subject based on the temperature distribution image (S220). The temperature sensor 120 may measure the body temperature of the measurement target from the temperature distribution image when a face is detected from the temperature distribution image when measuring the body temperature of the measurement target.

The temperature sensor 120 determines a temperature compensation value according to a change in the external environment (S230). The temperature compensation value may be determined as in Equation 1.

In Equation 1, δ represents a temperature compensation value, and ref is a person's standard body temperature, which may be set to 36.5 degrees, for example. x _ref represents the background body temperature, and the background body temperature will be described later based on FIG. 4 .

The temperature sensor 120 finally determines the body temperature by reflecting the temperature compensation value on the measured body temperature as shown in Equation 2 (S240). That is, the temperature sensor 120 corrects the measured body temperature using the temperature compensation value, and determines the final body temperature.

는 확정된 체온을 나타내고, x는 측정된 체온을 나타낸다. here,

denotes a confirmed body temperature, and x denotes a measured body temperature.

3 is a diagram illustrating a method of determining a temperature compensation value according to an embodiment of the present invention.

Referring to FIG. 3 , the temperature sensor 120 receives the measured body temperature [x _(t) ] of the subject at time t (S310).

The temperature sensor 120 extracts the background body temperature, that is, the past background body temperature [x _{ref(t-1)] of the measurement subjects up to time (t-1} ) in the past (S320). The past background body temperature [x _ref(t-1) ] represents a representative temperature value of the accumulated body temperatures of subjects measured in the past.

The temperature sensor 120 may remove noise from past background body temperatures [x _ref(t-1) ] of subjects in the past and currently measured body temperatures [x _(t) ] of subjects to be measured (S330).

Next, _the temperature sensor 120 determines the background body temperature [x _{ref ( t)} ] is updated (S340).

If the measured body temperature changes according to the change in the environment temperature, the amount of change in the measured body temperature according to the environmental temperature is reflected in the past measured temperatures of subjects, that is, the background body temperature (x _ref ). Therefore, the temperature sensor 120 defines the difference between the reference body temperature (ref) and the background body temperature (x _ref ) as a temperature compensation value according to various environmental changes, as shown in Equation 1, and uses the temperature compensation value to determine the current measurement subject The measured body temperature [x _(t) ] is corrected, and the corrected body temperature is determined as the final body temperature.

In this way, it is possible to compensate for a body temperature error value due to environmental temperature change or deviation between samples without a separate device requiring additional cost.

FIG. 4 is a diagram illustrating an example of the noise removal method shown in FIG. 3 .

As shown in FIG. 4, the past background body temperature [x _ref(t-1) ] of the past measurement subjects and the measured body temperature [x _(t) ] of the current measurement subject are passed through LPF (LowPassFilter) 122 to generate noise can be removed.

The LPF 122 can minimize reflection of the background body temperature by noise, i.e., a person with abnormal body temperature such as a person with high fever, by using a median filter. For example, by using the LPF 122, only the body temperatures of the central distribution excluding the upper and lower distribution values are passed among the body temperature distributions of past measurement subjects, and the central output from the LPF 122 through the average value calculation unit 124 is passed. By calculating the average value of the distributed body temperatures, the background body temperature [x _ref(t) ] may be updated with the average value of the centrally distributed body temperatures.

FIG. 5 is a view showing the temperature sensor shown in FIG. 1 .

Referring to FIG. 5 , the temperature sensor 120 includes a receiver 121, a temperature measurer 123, a compensation determiner 125, and a temperature corrector 127.

The receiving unit 121 receives the temperature distribution image of the subject to be measured from the thermal imaging camera 110 .

The temperature measurement unit 123 measures the temperature of the measurement target from the temperature distribution image.

The compensation determination unit 125 extracts past background body temperatures of past measurement subjects, updates the background body temperature using the measured temperature of the measurement subject and the past background body temperatures of the past measurement subjects, and uses the difference between the reference body temperature and the background body temperature to determine the external environment. Determine the temperature compensation value according to the change. The compensation determination unit 125 may include the LPF 122 and the average value calculation unit 124 shown in FIG. 4 to remove noise from the measured temperature of the measurement subject and the past background body temperature of the measurement subject.

The temperature compensating unit 127 determines the final temperature by reflecting the temperature compensation value to the measured temperature of the subject to be measured.

6 is a diagram illustrating a temperature sensing device according to another embodiment of the present invention.

Referring to FIG. 6 , the temperature sensing device 600 may represent a computing device in which the temperature sensing method described above is implemented.

The temperature sensing device 600 may include at least one of a processor 610 , a memory 620 , an input interface device 630 , an output interface device 640 and a storage device 650 . Each component may be connected by a common bus 660 to communicate with each other. In addition, each component may be connected through an individual interface or individual bus centered on the processor 610 instead of the common bus 660 .

The processor 610 may be implemented in various types such as an application processor (AP), a central processing unit (CPU), a graphic processing unit (GPU), and the like, and executes commands stored in the memory 620 or the storage device 650. It may be any semiconductor device that The processor 610 may execute a program command stored in at least one of the memory 620 and the storage device 650 . The processor 610 stores program commands for implementing at least some of the functions of the temperature measuring unit 123, the compensation determining unit 125, and the temperature correcting unit 127 described in 5 in the memory 620, and FIG. 1 It is possible to control the operation described above based on FIG. 5 to be performed.

The memory 620 and the storage device 650 may include various types of volatile or non-volatile storage media. For example, the memory 620 may include read-only memory (ROM) 621 and random access memory (RAM) 622 . In an embodiment of the present invention, the memory 620 may be located inside or outside the processor 610, and the memory 620 may be connected to the processor 610 through various known means.

Input interface device 630 is configured to provide data to processor 610 . The input interface device 630 may include the receiver 121 described in FIG. 5 .

Output interface device 640 is configured to output data from processor 610 . The output interface device 640 may output the final determined temperature to the outside.

Also, at least some of the temperature sensing methods according to embodiments of the present invention may be implemented as a program or software executed on a computing device, and the program or software may be stored in a computer-readable medium.

In addition, at least some of the temperature sensing methods according to embodiments of the present invention may be implemented as hardware that can be electrically connected to a computing device.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also included in the scope of the present invention. that fall within the scope of the right.

Claims (10)

In the temperature detection method of the fever detection system using a thermal imaging camera,
Obtaining a temperature distribution image of a measurement target captured by the thermal imaging camera;
Measuring the temperature of the measurement target based on the temperature distribution image;
Determining a temperature compensation value according to a change in the external environment using the measured temperature of the measurement object, and
Correcting the measured temperature of the measurement target using the temperature compensation value
Temperature sensing method comprising a. In paragraph 1,
The step of determining the temperature compensation value is
Extracting a past background temperature representing a representative value of the measured temperatures of accumulated past measurement objects;
Updating a background temperature using the measured temperature of the measurement object and the past background temperature; and
and determining the temperature compensation value from a difference between a preset reference temperature and the background temperature. In paragraph 2,
The updating step includes removing noise from the measured temperature of the measurement object and the past background temperature. In paragraph 2,
The updating step includes updating the background temperature as an average value of the measured temperature of the measurement object and the past background temperature. In the temperature detection device of the fever detection system using a thermal imaging camera,
A receiving unit for receiving a temperature distribution image of a measurement target from a thermal imaging camera;
A temperature measurement unit for measuring the temperature of the measurement target from the temperature distribution image;
A compensation determination unit for extracting a past background temperature of a past measurement object and determining a temperature compensation value according to a change in the external environment using the measured temperature of the measurement object and the past background temperature of the past measurement object; and
A temperature correction unit correcting the measured temperature of the measurement object using the temperature compensation value
A temperature sensing device comprising a. In paragraph 5,
The compensation determination unit updates the background temperature using the measured temperature of the measurement object and the past background temperature of the past measurement object, and calculates the temperature compensation value from a difference between a preset reference temperature and the background temperature. . In paragraph 6,
The temperature sensing device of claim 1 , wherein the compensation determination unit extracts a representative value of the measured temperatures of the past measurement objects as the past background temperature. In paragraph 6,
The temperature sensing device of claim 1 , wherein the compensation determination unit updates the background temperature with an average value of the measured temperature of the measurement object and the past background temperature. In paragraph 5,
The compensation determination unit includes a filter for removing noise from the measured temperature of the measurement object and the past background temperature of the past measurement object. In paragraph 9,
The temperature sensing device wherein the filter includes a median filter.

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