A temperature measurement method and thermal imaging temperature measurement device
By measuring and correcting the ambient background temperature, and using the temperature compensation curve to provide a reference standard for blackbody-less thermal imaging temperature measurement equipment, the influence of wind force and ambient temperature changes on temperature measurement accuracy is solved, and high-precision temperature measurement is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG UNIVIEW TECH CO LTD
- Filing Date
- 2021-02-01
- Publication Date
- 2026-05-15
AI Technical Summary
Thermal imaging temperature measurement equipment without a blackbody reference source has low temperature measurement accuracy under the influence of wind force and changes in ambient temperature, and existing technologies cannot provide an effective reference standard.
The background temperature of the environment in the image is measured by thermal imaging temperature measurement equipment, and a reference standard is provided by using temperature compensation curves and cyclic correction methods to reduce the influence of factors such as wind.
It improves the temperature measurement accuracy of blackbody-free thermal imaging temperature measurement equipment, reduces system complexity and cost, and does not rely on external temperature sensors.
Smart Images
Figure CN114838828B_ABST
Abstract
Description
Technical Field
[0001] This article relates to temperature measurement technology, particularly a temperature measurement method and a thermal imaging temperature measurement device. Background Technology
[0002] Currently, thermal imaging products are being shipped in large quantities, and these products can be broadly categorized into two types: those with a blackbody and those without. Products with a blackbody have a blackbody reference source, resulting in more accurate temperature measurements and less susceptibility to environmental fluctuations. However, the presence of the blackbody hardware increases cost and deployment complexity. Products without a blackbody offer more flexible deployment and lower cost, but the lack of a blackbody reference source makes them significantly affected by wind and ambient temperature during practical use, thus impacting measurement accuracy. Summary of the Invention
[0003] This application provides a temperature measurement method and a thermal imaging temperature measurement device, which can provide a reference standard for blackbody-free thermal imaging temperature measurement devices, thereby reducing the impact of factors such as wind on temperature measurement accuracy and improving temperature measurement accuracy.
[0004] This application provides a temperature measurement method, which may include:
[0005] The background temperature of the environment in the image is measured using a thermal imaging temperature measurement device;
[0006] The background temperature is used as the temperature measurement standard to calculate the temperature of the current target object.
[0007] In an exemplary embodiment of this application, measuring the background temperature of the environmental background in the image using the thermal imaging temperature measurement device may include:
[0008] The thermal imaging temperature measurement device is used to measure the background temperature T0 of the image background in real time.
[0009] The real-time measured background temperature value T0 is substituted into multiple relational formulas related to the background temperature, and the multiple relational formulas are solved iteratively to achieve cyclic correction of the background temperature until the background temperature reaches stability.
[0010] In an exemplary embodiment of this application, the relation may include:
[0011] The temperature compensation curve ΔT = F(Te) is measured in advance and stored in the thermal imaging temperature measurement device; where ΔT is the compensated temperature value, F(Te) refers to the function corresponding to the temperature compensation curve, and Te is the measured temperature of the same object in the environmental background under different background temperatures under ideal conditions.
[0012] The relationship between the measured temperature Te of the object, which is set by the user, and the actual background temperature Tm is: Te = Tm;
[0013] The relationship between the real-time measured background temperature T0 of the thermal imaging temperature measurement device and the compensated temperature value △T and the actual background temperature value Tm is: Tm=T0+△T.
[0014] In an exemplary embodiment of this application, substituting the real-time measured background temperature value T0 into multiple relational formulas related to the background temperature, and iteratively solving the multiple relational formulas to achieve cyclic correction of the background temperature until the background temperature reaches stability, may include:
[0015] The real-time measured background temperature value T0 is substituted into the system of equations consisting of ΔT=F(Te), Te=Tm and Tm=T0+ΔT, and the actual background temperature value Tm is iteratively corrected until the actual background temperature value Tm is in a stable state. The actual background temperature value Tm in the stable state is then taken as the background temperature.
[0016] In an exemplary embodiment of this application, the background temperature refers to the atmospheric temperature; pre-measuring the temperature compensation curve ΔT = F(Te) may include:
[0017] In a preset simulated atmospheric environment, the thermal imaging temperature measurement device is used to measure the temperature of the same object in the atmosphere at different atmospheric temperatures, and the measured temperature Te of the object corresponding to different atmospheric temperatures is obtained.
[0018] Connect the measured temperatures Te of the object corresponding to different atmospheric temperatures to obtain the influence curve of the thermal imaging temperature measurement device under the influence of atmospheric temperature; use the influence curve as the temperature compensation curve △T=F(Te).
[0019] In an exemplary embodiment of this application, the object may be a physical object in an atmospheric environment that can respond to changes in ambient temperature within a preset time period, or it may be a preset background area in an atmospheric environment.
[0020] In an exemplary embodiment of this application, the real-time measurement of the background temperature T0 of the image background using the thermal imaging temperature measurement device may include:
[0021] The thermal imaging temperature measurement device acquires thermal imaging video containing the environmental background.
[0022] The thermal imaging video is decomposed into video frames to obtain multiple frames of thermal imaging images;
[0023] Calculate the average brightness of the pixels in the target area in each frame of thermal imaging, and use the temperature value corresponding to the average brightness as the temperature measurement value of the corresponding frame of thermal imaging.
[0024] The average value of the temperature measurements corresponding to all thermal imaging images is calculated, and the average value of the calculated temperature measurements is used as the background temperature measurement value T0 obtained in real time by the thermal imaging temperature measurement device for the background of the image.
[0025] In an exemplary embodiment of this application, the target area may be the entire image area of each frame of thermal imaging, or it may be a preset portion of the image area within each frame of thermal imaging.
[0026] In an exemplary embodiment of this application, after acquiring multiple frames of thermal imaging images, the method may further include:
[0027] The thermal imaging image containing the heat-generating object is removed, and the background temperature measurement value T0 is calculated based on the remaining thermal imaging image; or,
[0028] Extract at least one segment of thermal imaging image that does not contain a heat-generating object from the entire thermal imaging image, and calculate the background temperature measurement value T0 based on the extracted thermal imaging image.
[0029] In an exemplary embodiment of this application, calculating the temperature of the current target object using the background temperature as a temperature measurement standard may include:
[0030] The temperature difference between the thermal imaging temperature measurement device and the background temperature is added to the background temperature to obtain the temperature of the current target object.
[0031] This application also provides a thermal imaging temperature measurement device, which may include a processor and a computer-readable storage medium, wherein the computer-readable storage medium stores instructions that, when executed by the processor, implement the temperature measurement method described in any of the above embodiments.
[0032] Compared with related technologies, the embodiments of this application may include: measuring the background temperature of the environmental background in the image using the thermal imaging temperature measurement device; and calculating the temperature of the current target object using the background temperature as a temperature measurement standard. This embodiment provides a reference standard for blackbody-less thermal imaging temperature measurement devices, thereby reducing the impact of factors such as wind on temperature measurement accuracy and improving measurement accuracy.
[0033] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description
[0034] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.
[0035] Figure 1 This is a flowchart of the temperature measurement method according to an embodiment of this application;
[0036] Figure 2 This is a schematic diagram of an embodiment of a temperature compensation curve according to an example of this application;
[0037] Figure 3 This is a block diagram of the thermal imaging temperature measurement device according to an embodiment of this application. Detailed Implementation
[0038] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.
[0039] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive scheme as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive schemes to form another unique inventive scheme as defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this application may be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.
[0040] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.
[0041] This application provides a temperature measurement method, such as... Figure 1 As shown, the method may include steps S101-S102:
[0042] S101. Measure the background temperature of the environment in the image using a thermal imaging temperature measurement device;
[0043] S102. Calculate the temperature of the current target object using the background temperature as the temperature measurement standard.
[0044] In an exemplary embodiment of this application, a scheme is provided that does not require a blackbody and uses background temperature as a reference standard, thereby reducing the impact of factors such as wind force on the accuracy of temperature measurement.
[0045] In an exemplary embodiment of this application, the embodiment can be applied to a thermal imaging temperature measurement device without a blackbody reference source or to a thermal imaging temperature measurement device with a blackbody reference source.
[0046] In an exemplary embodiment of this application, measuring the background temperature of the environmental background in the image using the thermal imaging temperature measurement device may include:
[0047] The thermal imaging temperature measurement device is used to measure the background temperature T0 of the image background in real time.
[0048] The real-time measured background temperature value T0 is substituted into multiple relational formulas related to the background temperature, and the multiple relational formulas are solved iteratively to achieve cyclic correction of the background temperature until the background temperature reaches stability.
[0049] In an exemplary embodiment of this application, the relation may include:
[0050] The temperature compensation curve ΔT = F(Te) is measured in advance and stored in the thermal imaging temperature measurement device; where ΔT is the compensated temperature value, F(Te) refers to the function corresponding to the temperature compensation curve, and Te is the measured temperature of the same object in the environmental background under different background temperatures under ideal conditions.
[0051] The relationship between the measured temperature Te of the object and the actual background temperature Tm is set as follows: Te = Tm; that is, the measured temperature Te of the object in the atmosphere is set to be the same as the actual background temperature Tm.
[0052] The relationship between the real-time measured background temperature T0 of the thermal imaging temperature measurement device and the compensated temperature value △T and the actual background temperature value Tm is: Tm=T0+△T.
[0053] In an exemplary embodiment of this application, substituting the real-time measured background temperature value T0 into multiple relational formulas related to the background temperature, and iteratively solving the multiple relational formulas to achieve cyclic correction of the background temperature until the background temperature reaches stability, may include:
[0054] The real-time measured background temperature value T0 is substituted into the system of equations consisting of ΔT=F(Te), Te=Tm and Tm=T0+ΔT, and the actual background temperature value Tm is iteratively corrected until the actual background temperature value Tm is in a stable state. The actual background temperature value Tm in the stable state is then taken as the background temperature.
[0055] In an exemplary embodiment of this application, in common indoor and outdoor environments, since the background is usually an object that has been exposed to the atmosphere for a long time, the background temperature and the atmospheric temperature are very close. The background temperature is the atmospheric temperature in the background environment.
[0056] In an exemplary embodiment of this application, a negative feedback can be implemented in the thermal imaging temperature measurement device based on the equation set composed of △T=F(Te), Te=Tm and Tm=T0+△T, thereby measuring the ambient temperature value very accurately.
[0057] In the exemplary embodiments of this application, the industry generally adopts a fully enclosed physical structure to reduce the direct impact of wind on the thermal imaging sensor (i.e., thermal imaging temperature measurement device) in response to the influence of wind. Regarding the influence of ambient temperature, an external temperature sensor is used to measure the ambient temperature, followed by corresponding temperature compensation. However, when using a blackbody-less thermal imaging sensor for temperature measurement, due to the lack of a reference source, the measured temperature fluctuates by approximately 0.7-2°C when affected by wind; using an external temperature sensor requires additional external hardware. The solution of this application, however, achieves high-precision ambient temperature measurement without relying on a blackbody, eliminates the need for an external temperature sensor, reduces system complexity, and allows for further precise measurement of the temperature of known materials without the need for a blackbody, significantly reducing measurement costs while still ensuring measurement accuracy.
[0058] In an exemplary embodiment of this application, pre-measuring the temperature compensation curve ΔT = F(Te) may include:
[0059] In a preset simulated atmospheric environment, the thermal imaging temperature measurement device is used to measure the temperature of the same object in the atmosphere at different atmospheric temperatures, and the measured temperature Te of the object corresponding to different atmospheric temperatures is obtained.
[0060] Connect the measured temperatures Te of the object corresponding to different atmospheric temperatures to obtain the influence curve of the thermal imaging temperature measurement device under the influence of atmospheric temperature; use the influence curve as the temperature compensation curve △T=F(Te).
[0061] In an exemplary embodiment of this application, a model can be pre-modeled in a laboratory to set up a simulated atmospheric environment, and the relationship between ΔT and Te (i.e., the temperature compensation curve) can be measured in that environment and integrated into a thermal imaging temperature measurement device.
[0062] In an exemplary embodiment of this application, the simulated atmospheric environment may be the environment in which the thermal imaging temperature measurement device is placed.
[0063] In exemplary embodiments of this application, as Figure 2 The diagram shown is a schematic representation of an embodiment of a temperature compensation curve. This diagram illustrates that the temperature sensor measures different values for the same object at different atmospheric temperatures, where the actual temperature of the object is 35°C.
[0064] In an exemplary embodiment of this application, the object may be a physical object in an atmospheric environment that can respond to changes in ambient temperature within a preset time period, or it may be a preset background area in an atmospheric environment.
[0065] In an exemplary embodiment of this application, the preset duration can be customized as needed.
[0066] In an exemplary embodiment of this application, a temperature close to the atmospheric temperature can be obtained by measuring the average temperature of the background image. If calculations for the entire background image are insufficient, a specific area (i.e., a preset background area) can be set within the background image, allowing this specific area to be fully exposed to the atmosphere, thereby achieving the purpose of measuring the atmospheric temperature. From the above analysis, Te = Tm can be obtained.
[0067] In an exemplary embodiment of this application, the real-time measurement of the background temperature T0 of the image background using the thermal imaging temperature measurement device may include:
[0068] The thermal imaging temperature measurement device acquires thermal imaging video containing the environmental background.
[0069] The thermal imaging video is decomposed into video frames to obtain multiple frames of thermal imaging images;
[0070] Calculate the average brightness of the pixels in the target area in each frame of thermal imaging, and use the temperature value corresponding to the average brightness as the temperature measurement value of the corresponding frame of thermal imaging.
[0071] The average value of the temperature measurements corresponding to all thermal imaging images is calculated, and the average value of the calculated temperature measurements is used as the background temperature measurement value T0 obtained in real time by the thermal imaging temperature measurement device for the background of the image.
[0072] In an exemplary embodiment of this application, thermal imaging temperature measurement data (i.e., thermal imaging video) can be decomposed according to the processing method of video frames to obtain a series of temperature measurement data (i.e., multiple frames of thermal imaging images). The average value of the brightness of the pixels in each thermal imaging image is calculated to obtain the average brightness value. Each average brightness value can be resolved into a temperature value, i.e., the temperature measurement value corresponding to the thermal imaging image of that frame.
[0073] In an exemplary embodiment of this application, the background temperature measurement value T0 measured in real time for the background of the image can be obtained by averaging the temperature measurement values corresponding to all frames of thermal imaging multiple times.
[0074] In an exemplary embodiment of this application, the target area may be the entire image area of each frame of thermal imaging, or it may be a preset portion of the image area within each frame of thermal imaging.
[0075] In an exemplary embodiment of this application, the calculation of background temperature may not be limited to all pixels of the background image, but may be performed only on a portion of the background image, or only on a preset object within the background image.
[0076] In an exemplary embodiment of this application, after acquiring multiple frames of thermal imaging images, the method may further include:
[0077] The thermal imaging image containing the heat-generating object is removed, and the background temperature measurement value T0 is calculated based on the remaining thermal imaging image; or,
[0078] Extract at least one segment of thermal imaging image that does not contain a heat-generating object from the entire thermal imaging image, and calculate the background temperature measurement value T0 based on the extracted thermal imaging image.
[0079] In an exemplary embodiment of this application, in order to avoid the presence of heat-generating objects, such as people or animals, in the background image during background temperature calculation, thereby affecting the background temperature calculation and reducing the calculation accuracy, thermal imaging images containing heat-generating objects can be removed, or only thermal imaging images that do not contain heat-generating objects can be selected, or background extraction can be performed on thermal imaging images containing heat-generating objects to obtain thermal imaging images with a pure background image, or thermal imaging video of a sufficiently long time can be collected so that the number of thermal imaging images that do not contain heat-generating objects is much greater than the number of thermal imaging images that contain heat-generating objects, thereby ignoring thermal imaging images that contain heat-generating objects.
[0080] In an exemplary embodiment of this application, calculating the temperature of the current target object using the background temperature as a temperature measurement standard may include:
[0081] The temperature difference between the thermal imaging temperature measurement device and the background temperature is added to the background temperature to obtain the temperature of the current target object.
[0082] In an exemplary embodiment of this application, after obtaining the temperature measurement standard (i.e., background temperature), the temperature of the target object (such as a person) can be calculated according to the prior art. This may include, but is not limited to, adding the temperature difference between the thermal imaging temperature measurement device and the background temperature to the background temperature to obtain the current temperature of the target object.
[0083] In an exemplary embodiment of this application, the method may further include: correcting the compensated temperature value ΔT according to a PID algorithm.
[0084] This application also provides a thermal imaging temperature measurement device 1, such as... Figure 3 As shown, it may include a processor 11 and a computer-readable storage medium 12, wherein the computer-readable storage medium 12 stores instructions that, when executed by the processor 11, implement the temperature measurement method described above.
[0085] In the exemplary embodiments of this application, any of the embodiments in the method embodiments described above are applicable to the device embodiments.
[0086] It will be understood by those skilled in the art that all or some of the steps, systems, or apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.
Claims
1. A temperature measurement method, characterized in that, The method includes: The background temperature of the environment in the image is measured using a thermal imaging temperature measurement device; The background temperature is used as the temperature measurement standard to calculate the temperature of the current target object; Measuring the background temperature of the environmental background in the image using the thermal imaging temperature measurement device includes: The thermal imaging temperature measurement device is used to measure the background temperature T0 of the image background in real time. The real-time measured background temperature value T0 is substituted into multiple relational formulas related to the background temperature, and the multiple relational formulas are solved iteratively to achieve cyclic correction of the background temperature until the background temperature reaches stability. The relational expression includes: The temperature compensation curve ΔT = F(Te) is measured in advance and stored in the thermal imaging temperature measurement device; where ΔT is the compensated temperature value, F() refers to the function corresponding to the temperature compensation curve, and Te is the measured temperature of the same object in the environmental background under different background temperatures under ideal conditions; The relationship between the measured temperature Te of the object, which is set by the user, and the actual background temperature Tm is: Te = Tm; The relationship between the real-time measured background temperature T0 of the thermal imaging temperature measurement device and the compensated temperature value △T and the actual background temperature value Tm is: Tm = T0 + △T.
2. The temperature measurement method according to claim 1, characterized in that, The step of substituting the real-time measured background temperature value T0 into multiple relational formulas related to the background temperature, and iteratively solving these formulas to achieve cyclical correction of the background temperature until the background temperature reaches stability includes: The real-time measured background temperature value T0 is substituted into the system of equations consisting of ΔT = F(Te), Te = Tm, and Tm = T0 + ΔT. The actual background temperature value Tm is then iteratively corrected until it reaches a stable state. The stable background temperature value Tm is then taken as the background temperature.
3. The temperature measurement method according to claim 1, characterized in that, The background temperature refers to the atmospheric temperature. The pre-measured temperature compensation curve ΔT = F(Te) includes: In a preset simulated atmospheric environment, the thermal imaging temperature measurement device is used to measure the temperature of the same object in the atmosphere at different atmospheric temperatures, and the measured temperature Te of the object corresponding to different atmospheric temperatures is obtained. Connect the measured temperatures Te of the object corresponding to different atmospheric temperatures to obtain the influence curve of the thermal imaging temperature measurement device when affected by atmospheric temperature; use the influence curve as the temperature compensation curve △T = F(Te).
4. The temperature measurement method according to claim 3, characterized in that, The object is a physical object in an atmospheric environment that can respond to changes in ambient temperature within a preset time period, or a preset background area in an atmospheric environment.
5. The temperature measurement method according to claim 1, characterized in that, The real-time measurement of the background temperature T0 of the image background using the thermal imaging temperature measurement device includes: The thermal imaging temperature measurement device acquires thermal imaging video containing the environmental background. The thermal imaging video is decomposed into video frames to obtain multiple frames of thermal imaging images; Calculate the average brightness of the pixels in the target area in each frame of thermal imaging, and use the temperature value corresponding to the average brightness as the temperature measurement value of the corresponding frame of thermal imaging. The average value of the temperature measurements corresponding to all thermal imaging images is calculated, and the average value of the calculated temperature measurements is used as the background temperature measurement value T0 obtained in real time by the thermal imaging temperature measurement device for the background of the image.
6. The temperature measurement method according to claim 5, characterized in that, After acquiring multiple frames of thermal imaging images, the method further includes: The thermal imaging image containing the heat-generating object is removed, and the background temperature measurement value T0 is calculated based on the remaining thermal imaging image; or, Extract at least one segment of thermal imaging image that does not contain a heat-generating object from the entire thermal imaging image, and calculate the background temperature measurement value T0 based on the extracted thermal imaging image.
7. A thermal imaging temperature measurement device, comprising a processor and a computer-readable storage medium, wherein the computer-readable storage medium stores instructions, characterized in that, When the instruction is executed by the processor, the temperature measurement method as described in any one of claims 1-6 is implemented.