A method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery

Abstract

This application provides a method for identifying wildfire ignition points based on high-resolution satellite remote sensing imagery. The method includes: acquiring remote sensing images of the target location at the current time across multiple bands; determining the normalized combustion index (NCI) of the remote sensing images based on their apparent emissivity across the multiple bands; determining the apparent reflectivity and corresponding apparent brightness temperature of the remote sensing images that satisfy multiple wavelength conditions; identifying the target location as a suspected ignition point when the NCI satisfies a first preset condition and / or the apparent reflectivity and apparent brightness temperature simultaneously satisfy a second preset condition; and eliminating interference data from the suspected ignition point to determine whether a fire has actually occurred at the target location. This application analyzes the target location for fire location using multi-band remote sensing imagery from high-resolution satellites, which is more accurate than traditional meteorological satellite analysis and avoids missing small-area wildfires.

Description

Technical Field

[0001] This application relates to the field of disaster early warning technology, specifically to a method, processor, device, and storage medium for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing images. Background Technology

[0002] Mountainous areas have complex terrain and dense vegetation, posing a significant fire hazard, especially during dry weather. Forest fires caused by faults near power transmission lines require particular attention. In the early stages of a fire, timely containment is an effective prevention measure. Current technologies primarily rely on traditional meteorological satellites to acquire mid-wave infrared remote sensing images of the ground to determine the presence of fire points.

[0003] However, the above methods are limited by the resolution of satellite remote sensing imagery when used for fire prevention in mountainous areas, and many small wildfires cannot be detected in time. Existing high-resolution satellite remote sensing imagery often does not include the mid-infrared band, making it impossible to use the above methods to determine the presence of fire points on the ground, which could lead to the spread of fire and cause incalculable losses. Summary of the Invention

[0004] The purpose of this application is to provide a method, processor, device, and storage medium for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing images.

[0005] To achieve the above objectives, the first aspect of this application provides a method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery, comprising:

[0006] Acquire remote sensing images of the target location in multiple bands at the current time;

[0007] The normalized combustion index of remote sensing images is determined based on the apparent emissivity of remote sensing images in multiple bands.

[0008] Determine the apparent reflectance and corresponding apparent brightness temperature of remote sensing images that satisfy multiple wavelength conditions.

[0009] If the normalized flammability index meets the first preset condition and / or the apparent reflectance and apparent brightness temperature simultaneously meet the second preset condition, the target location is determined as a suspected ignition point.

[0010] Interference data is eliminated from suspected fire points to determine whether a fire has actually occurred at the target location.

[0011] In this embodiment of the application, determining the normalized burn index of a remote sensing image based on the apparent emissivity of the remote sensing image in multiple bands includes: determining the normalized burn index according to formula (1):

[0012]

[0013] Where NBRS is the normalized combustion index, ρ 0.86 ρ refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. 1.6 This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 1.6 μm is within a second preset range, ρ. 2.1 It refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 2.1μm is within the third preset range, and k is a preset coefficient; the first preset condition refers to the normalized combustion index being within the preset ignition point identification range.

[0014] In this embodiment, the apparent reflectance and apparent brightness temperature are determined to simultaneously meet the second preset condition when all of the following conditions are met: the first apparent reflectance is greater than the first threshold; the average difference between the first apparent reflectance and the historical apparent reflectance for each day within a preset historical time period is greater than the second threshold; the ratio of the second apparent reflectance to the first apparent reflectance is less than a first value; and the difference between the first apparent brightness temperature and the second apparent brightness temperature is greater than a second value. Wherein, the first apparent reflectance refers to the apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within a fourth preset range, and the first threshold refers to the maximum historical data value of the apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within the fourth preset range. The 7% value refers to the historical apparent reflectance, which is the average apparent reflectance of the mid-wave infrared band within the fourth preset range when the difference between the wavelength and 4μm is on day (ti). The second threshold is the value of 7% of the largest historical difference in apparent reflectance data of the mid-wave infrared band within the fourth preset range when the difference between the wavelength and 4μm is within the fourth preset range. The second apparent reflectance is the apparent reflectance of the short-wave infrared band within the second preset range when the difference between the wavelength and 1.6μm is within the second preset range. The first apparent brightness temperature is the apparent brightness temperature of the mid-wave infrared band within the fourth preset range when the difference between the wavelength and 4μm is within the fourth preset range, in K. The second apparent brightness temperature is the apparent brightness temperature of the mid-wave infrared band within the fifth preset range when the difference between the wavelength and 11μm is within the fifth preset range, in K.

[0015] In this embodiment of the application, the interference data exclusion for suspected ignition points includes: excluding suspected ignition points caused by any one of water bodies, solar flares, or clouds.

[0016] In this embodiment of the application, a suspected ignition point is confirmed to be caused by water if the apparent reflectance simultaneously meets all of the following conditions: the third apparent reflectance is less than the third value; the fourth apparent reflectance is less than the fourth value; the ratio between the difference between the fourth and fifth apparent reflectances and the sum of the fourth and fifth apparent reflectances is less than the fifth value; wherein, the third apparent reflectance refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 2.1 μm is within the third preset range, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within the first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within the sixth preset range.

[0017] In this embodiment of the application, the method further includes: obtaining the observed zenith angle, solar altitude angle, and relative azimuth angle of the target location at the current moment; determining the flare angle of the target location at the current moment based on the observed zenith angle, solar altitude angle, and relative azimuth angle; confirming that the suspected ignition point is caused by a flare when the apparent reflectance simultaneously meets all of the following conditions: the fourth apparent reflectance is greater than the sixth value; the fifth apparent reflectance is greater than the seventh value; and the flare angle is less than a preset angle; wherein, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within the first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within the sixth preset range.

[0018] In this embodiment of the application, a suspected ignition point is confirmed to be caused by clouds if the apparent reflectance meets any of the following conditions: the sum of the fourth and fifth apparent reflectances is greater than the eighth value, and the third apparent brightness temperature is less than the first temperature; the sum of the fourth and fifth apparent reflectances is greater than the ninth value and less than or equal to the eighth value, and the third apparent brightness temperature is greater than or equal to the first temperature and less than the second temperature; wherein, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86μm is within the first preset range, the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65μm is within the sixth preset range, and the third apparent brightness temperature refers to the apparent brightness temperature of the mid-infrared band where the difference between the wavelength and 12μm is within the seventh preset range, and the unit is K.

[0019] A second aspect of this application provides a processor configured to perform the above-described method.

[0020] A third aspect of this application provides a wildfire ignition point identification device based on high-resolution satellite remote sensing imagery. The device includes: a remote sensing image acquisition module for acquiring remote sensing images of the target location at the current time in multiple bands; a suspected ignition point confirmation module for determining the normalized combustion index of the remote sensing images based on the apparent emissivity of the remote sensing images in multiple bands; determining the apparent reflectivity and corresponding apparent brightness temperature of the remote sensing images that satisfy multiple wavelength conditions; determining the target location as a suspected ignition point when the normalized combustion index satisfies a first preset condition and / or the apparent reflectivity and apparent brightness temperature simultaneously satisfy a second preset condition; and an interference elimination module for eliminating interference data from the suspected ignition point to determine whether a fire has actually occurred at the target location.

[0021] A fourth aspect of this application provides a machine-readable storage medium storing instructions, characterized in that, when executed by a processor, the instructions cause the processor to be configured to perform the above-described method.

[0022] Through the above technical solution, this application can acquire multi-band infrared remote sensing images using high-resolution satellites and meteorological satellites, thereby determining whether a fire point exists at the target location. Compared with traditional meteorological satellite identification methods, this application utilizes high-resolution short-wave infrared remote sensing images and near-wave infrared remote sensing images acquired by high-resolution satellites, resulting in higher resolution and more accurate identification of fire points, avoiding the missed detection of small-area wildfires.

[0023] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0024] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings:

[0025] Figure 1 The illustration shows a flowchart of a method for identifying the location of a wildfire ignition point based on high-resolution satellite remote sensing imagery according to an embodiment of this application;

[0026] Figure 2 This schematic diagram illustrates the structural block diagram of a wildfire ignition point location identification device based on high-resolution satellite remote sensing imagery according to an embodiment of this application;

[0027] Figure 3 The diagram illustrates the internal structure of a computer device according to an embodiment of this application. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] Figure 1 The illustration shows a schematic flowchart of a method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery according to an embodiment of this application. Figure 1 As shown in one embodiment of this application, a method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery is provided, including the following steps:

[0030] S102, acquire remote sensing images of the target location in multiple bands at the current time.

[0031] S104. Determine the normalized combustion index of remote sensing images based on the apparent emissivity of remote sensing images in multiple bands.

[0032] S106, determine the apparent reflectance and corresponding apparent brightness temperature of remote sensing images that satisfy multiple wavelength conditions respectively.

[0033] S108, if the normalized flammability index meets the first preset condition and / or the apparent reflectance and apparent brightness temperature simultaneously meet the second preset condition, the target location is determined as a suspected ignition point.

[0034] S110, interference data is eliminated from suspected fire points to determine whether a fire has actually occurred at the target location.

[0035] High-resolution satellites and meteorological satellites can acquire remote sensing images of ground target locations. Remote sensing images are films or photographs that record the electromagnetic wave intensity of various ground features and can contain image data across multiple wavelengths. Near-infrared waves refer to infrared waves with wavelengths ranging from 0.35 μm to 1 μm; short-wave infrared waves refer to infrared waves with wavelengths ranging from 1 μm to 3 μm; and mid-wave infrared waves refer to infrared waves with wavelengths ranging from 3 μm to 40 μm. The apparent reflectance of remote sensing images is the ratio of the energy reflected from the surface of a ground feature to the solar incident energy near the surface. The normalized combustion index (NCR) enhances the numerical value of fire-affected areas by calculating the ratio of near-infrared to short-wave infrared bands. Apparent brightness temperature is positively correlated with the radiation intensity of an object. The processor can determine the presence of ignition points in a target area based on its apparent brightness temperature. The processor can determine the apparent reflectance and thus the apparent brightness temperature from the aforementioned remote sensing images.

[0036] In this application, to determine whether a fire has occurred in a target area, remote sensing image data across multiple bands can be analyzed. First, the processor acquires remote sensing images of the target location at the current time across multiple bands, and determines the apparent reflectance of the remote sensing images under multiple wavelength conditions based on these images. The near-wave infrared and short-wave infrared images are acquired by high-resolution satellites, while the mid-wave infrared images are also acquired by high-resolution satellites. Based on the apparent reflectance of these remote sensing images under multiple wavelength conditions, the processor can determine the normalized combustion index (NCI) of the remote sensing images. If the NCI meets a first preset condition, the target location can be confirmed as a suspected fire point. Alternatively, the processor can acquire the apparent reflectance and corresponding apparent brightness temperature of a remote sensing image under another wavelength condition from the remote sensing images across multiple bands. If the apparent reflectance and apparent brightness temperature meet a second wavelength condition, the processor can also determine that a suspected fire point exists at the target location. After confirming that the target location is a suspected fire point, several common interferences are eliminated to determine whether a fire has occurred at the target location. In other words, if the processor determines that the suspected ignition point is one of the common types of interference, then no fire has occurred at the target location; otherwise, a fire has occurred.

[0037] In one specific embodiment, the processor acquires remote sensing images of multiple bands, including remote sensing images of bands (0.86±0.05)μm, (1.6±0.05)μm, (2.1±0.05)μm, (4±0.05)μm, and (11±0.05)μm. Based on the apparent reflectance of the remote sensing images of the (0.86±0.05)μm, (1.6±0.05)μm, and (2.1±0.05)μm bands, the processor determines the normalized combustion index (NCI) of the target location. If the NCI falls within a first preset condition, the processor can determine the target location as a suspected ignition point. Alternatively, the processor determines whether the second preset condition is met based on the apparent reflectance of (1.6±0.05)μm and (4±0.05)μm and the apparent brightness temperature of the (4±0.05)μm and (11±0.05)μm remote sensing images. If the second preset condition is met, the processor can determine that the target location is a suspected fire point. The processor eliminates possible interference situations that may occur at the suspected fire point. If one or more interference situations occur, the processor determines that no fire has occurred at the target location; otherwise, a fire has occurred at the target location.

[0038] By employing the above method, this application can acquire multi-band infrared remote sensing images using high-resolution satellites and meteorological satellites, thereby determining whether a fire point exists at the target location. Compared to traditional meteorological satellite identification methods, this application utilizes high-resolution short-wave infrared remote sensing images and near-wave infrared remote sensing images, which have higher resolution and can more accurately identify fire points, avoiding the missed detection of small-area wildfires.

[0039] In one embodiment, determining the normalized burn index of a remote sensing image based on its apparent emissivity across multiple bands includes: determining the normalized burn index according to formula (1):

[0040]

[0041] Where NBRS is the normalized combustion index, ρ 0.86 ρ refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. 1.6 This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 1.6 μm is within a second preset range, ρ. 2.1 This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 2.1 μm is within the third preset range, where k is a preset coefficient; the first preset condition refers to the normalized flammability index being within the preset ignition point identification range. ρ 0.86 This refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. For example, if the first preset range is 0.05 μm, then the reflectance of the near-infrared band within the range of (0.86 ± 0.05) μm all fall within the near-infrared band where the difference between the wavelength and 0.86 μm is within the first preset range. Similarly, ρ can be determined. 1.6 ρ 2.1 The corresponding infrared band. The processor can determine the normalized combustion index of the target location using the above formula (1). If the normalized combustion index is within the preset ignition point identification range, it can be determined that there is a suspected ignition point at the target location.

[0042] In one embodiment, apparent reflectance and apparent brightness temperature are determined to simultaneously meet a second preset condition if all of the following conditions are met: the first apparent reflectance is greater than a first threshold; the average difference between the first apparent reflectance and the historical apparent reflectance for each day within a preset historical time period is greater than a second threshold; the ratio of the second apparent reflectance to the first apparent reflectance is less than a first value; and the difference between the first apparent brightness temperature and the second apparent brightness temperature is greater than a second value. Wherein, the first apparent reflectance refers to the apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within a fourth preset range, and the first threshold refers to the maximum historical data value of 7 for apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within a fourth preset range. The percentage value refers to the average apparent reflectance of the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm on day (ti). The second threshold refers to 7% of the maximum historical difference in apparent reflectance data for the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm. The second apparent reflectance refers to the apparent reflectance of the short-wave infrared band within the second preset range for wavelength differences of 1.6μm. The first apparent brightness temperature refers to the apparent brightness temperature of the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm, in K. The second apparent brightness temperature refers to the apparent brightness temperature of the mid-wave infrared band within the fifth preset range for wavelength differences of 11μm, in K.

[0043] The processor determines that the first apparent reflectivity ρ4 is greater than the first threshold th. s，1 In this case, it is confirmed that the apparent reflectance and apparent brightness temperature meet the first condition of the second preset condition. The processor obtains the apparent reflectance of the preset band for each day within the preset historical time period, compares it with the current first apparent reflectance ρ4, and compares the first apparent reflectance ρ4 with the historical apparent reflectance ρ4 for each day within the preset historical time period. 4，t-i The mean of the difference is greater than the second threshold th s，2 In this case, the processor determines that the apparent reflectance and apparent brightness temperature meet the second preset condition. The historical time period can be the past 7 days compared to the current time. The processor confirms the second apparent reflectance ρ. 1.6 If the ratio between the apparent reflectance ρ4 and the first apparent reflectance is less than the first value, then the apparent reflectance and apparent luminance temperature are determined to satisfy the third condition of the second preset condition. The processor determines the first apparent luminance temperature T4 and the second apparent luminance temperature T... 11 If the difference between the apparent reflectance and apparent brightness temperature is greater than the second value, it is determined that the fourth condition of the second preset condition is met. If the processor confirms that the apparent reflectance and apparent brightness temperature simultaneously meet all four conditions, it confirms that the apparent reflectance and apparent brightness temperature meet the second preset condition, thereby confirming the target location as a suspected ignition point. Among these conditions, the first threshold th...s，1 This can be a value representing 7% of the historical maximum apparent reflectance data for the mid-infrared band where the difference between the wavelength and 4 μm falls within a fourth preset range. For example, if the mid-infrared band where the difference between the wavelength and 4 μm falls within the fourth preset range is a mid-infrared band with a wavelength of (4 ± 0.05) μm, and its historical maximum value is 0.8, then the first threshold is 0.056. The second threshold is th... s，2 This refers to 7% of the maximum difference in historical apparent reflectance data for the mid-infrared band within the fourth preset range where the difference between the wavelength and 4μm is within that range. For example, if the maximum and minimum values ​​of historical apparent reflectance data for the mid-infrared band within the fourth preset range where the difference between the wavelength and 4μm is within the range are 0.7 and 0.5 respectively, then the maximum difference is 0.2, and the second threshold is 0.014. The first apparent brightness temperature T4 refers to the apparent brightness temperature of the mid-infrared band within the fourth preset range where the difference between the wavelength and 4μm is within the range, in K. The second apparent brightness temperature T... 11 It refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 11μm is within the fifth preset range, and the unit is K.

[0044] In one embodiment, data interference removal for suspected fire points includes excluding suspected fire points caused by any of the following: water bodies, solar flares, or clouds. Infrared band data in remote sensing images of water bodies, solar flares, or clouds are easily identified as suspected fire points. Therefore, the processor needs to perform interference removal to determine whether a suspected fire point has actually ignited.

[0045] In one embodiment, a suspected ignition point is confirmed to be caused by water if the apparent reflectance simultaneously meets all of the following conditions: the third apparent reflectance is less than the third value; the fourth apparent reflectance is less than the fourth value; the ratio between the difference between the fourth and fifth apparent reflectances and the sum of the fourth and fifth apparent reflectances is less than the fifth value; wherein, the third apparent reflectance refers to the apparent reflectance of the shortwave infrared band where the difference between the wavelength and 2.1 μm is within a third preset range, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range.

[0046] In one embodiment, the method further includes: acquiring the observed zenith angle, solar altitude angle, and relative azimuth angle of the target location at the current moment; determining the flare angle of the target location at the current moment based on the observed zenith angle, solar altitude angle, and relative azimuth angle; confirming that the suspected ignition point is caused by a flare if the apparent reflectance simultaneously meets all of the following conditions: the fourth apparent reflectance is greater than the sixth value; the fifth apparent reflectance is greater than the seventh value; and the flare angle is less than a preset angle; wherein, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range. For example, the third value can be 0.05, the fourth value can be 0.15, and the fifth value can be 0.

[0047] The processor can determine the current zenith angle, solar altitude angle, and relative azimuth angle of the target location based on high-resolution satellite data. The zenith angle is the angle between the incident direction of sunlight and the zenith direction, and is the complementary angle of the altitude angle. The solar altitude angle is the angle between the incident direction of sunlight and the ground plane. The relative azimuth angle is the angle measured clockwise from the north direction of the target location to the incident direction of sunlight. After determining the current zenith angle, solar altitude angle, and relative azimuth angle of the target location, the processor can determine the flare angle using formula (2):

[0048] θ r =sin(θ) v sin(θ) s cos(ψ) + cos(θ) v cos(θ) s ) formula (2);

[0049] Where, θ r For the flare angle, θ v To observe the zenith angle, θ s Here, ψ represents the solar altitude angle, and ψ represents the relative azimuth angle. If the processor determines that the fourth apparent reflectivity is greater than the sixth value, the fifth apparent reflectivity is greater than the seventh value, and the flare angle is less than a preset angle, then the suspected ignition point at the target location is determined to be caused by a flare. For example, the sixth value can be 0.3, the seventh value can be 0.3, and the preset angle can be 40°.

[0050] In one embodiment, a suspected ignition point is confirmed to be caused by clouds if the apparent reflectance meets any of the following conditions: the sum of the fourth and fifth apparent reflectances is greater than the eighth value, and the third apparent brightness temperature is less than the first temperature; or the sum of the fourth and fifth apparent reflectances is greater than the ninth value and less than or equal to the eighth value, and the third apparent brightness temperature is greater than or equal to the first temperature and less than the second temperature. Wherein, the fourth apparent reflectance refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range; the fifth apparent reflectance refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range; and the third apparent brightness temperature refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 12 μm is within a seventh preset range, with units in K.

[0051] In a specific embodiment, the first, second, third, fourth, fifth, sixth, and seventh preset ranges in the above embodiments are those whose absolute values ​​of the differences from their corresponding wavelengths are less than 0.05 μm. For example, the first preset range corresponds to ρ 0.86 The first preset range refers to the near-infrared band where the absolute value of the difference from 0.86μm is less than 0.5, that is, the near-infrared band within the range of (0.86±0.05)μm.

[0052] The processor acquires multi-band remote sensing imagery of the target location at the current time, including: acquiring infrared bands at (0.86±0.05)μm, (1.6±0.05)μm, (4±0.05)μm, (11±0.05)μm, (2.1±0.05)μm, (0.65±0.05)μm, and (12±0.05)μm at the target location at the current time, with apparent reflectance corresponding to ρ respectively. 0.86 ρ 1.6 ,ρ4,ρ 11 ρ 2.1 ρ 0.65 ρ 12Among them, the infrared remote sensing images of the (4±0.05)μm, (11±0.05)μm, and (12±0.05)μm bands were acquired by meteorological satellites, and the rest were acquired by high-resolution satellites. The reflectance and apparent brightness temperature of the corresponding infrared bands were determined. The processor confirmed the normalized combustion index of the remote sensing image at the target location according to formula (1). If the combustion index is within the preset ignition point identification range, it was determined that the normalized combustion index meets the first preset condition, and thus the target location can be determined as a suspected ignition point. Alternatively, the target location is determined as a suspected ignition point if the apparent reflectance and apparent brightness temperature meet the second preset condition. The second preset condition includes four conditions. The first condition is that the apparent reflectance of ρ4 is greater than 7% of the maximum value of the historical data of the apparent reflectance of the mid-wave infrared band within the wavelength range of (4±0.05)μm at the target location. For example, this value can be 0.056. The second condition is that ρ4 and the historical apparent reflectance ρ of each day in the historical period are compared. 4，t-i If the mean difference is greater than 7% of the maximum historical difference in apparent reflectance data for the mid-infrared band within the wavelength range of (4±0.05) μm at the target location, for example, if the maximum difference is 0.2, then 7% of the maximum difference is 0.014. The third point is ρ. 1.6 The ratio of ρ4 to the apparent reflectance is greater than the first value, for example, the first value can be 0.4. The fourth condition is that the difference between the apparent brightness temperature in the mid-infrared band within the wavelength range of (4±0.05)μm and the apparent brightness temperature in the mid-infrared band within the wavelength range of (11±0.05)μm is greater than the second value, for example, the second value can be zero. If all four conditions are met simultaneously, the apparent reflectance and apparent brightness temperature are determined to meet the second preset condition. If the processor determines that the normalized flammability index meets the first preset condition or that the apparent reflectance and apparent brightness temperature meet the second preset condition, the target location is determined to be a suspected ignition point.

[0053] If the processor determines that a target location is a suspected ignition point, it can perform interference elimination to rule out suspected ignition points caused by water, flares, or clouds. The processor can confirm that a suspected ignition point is caused by water if the apparent reflectance simultaneously meets all of the following conditions: ρ 2.1 Less than the third value, ρ 0.86 Less than the fourth value, (ρ) 0.86 -ρ 0.65 ) / (ρ 0.86 +ρ 0.65The third value can be 0.05, the fourth value can be 0.15, and the fifth value can be zero. Under the condition that the above three conditions are met, the suspected ignition point is determined to be caused by water. The processor can obtain the observed zenith angle, solar altitude angle, and relative azimuth angle of the target location at the current time, and determine the flare angle according to the obtained observed zenith angle, solar altitude angle, relative azimuth angle, and formula (2) in the above embodiment. The processor can determine that the suspected ignition point is caused by a flare when the flare angle of the target location and the apparent reflectivity of the target location simultaneously meet the following conditions. The conditions include: ρ 0.86 Greater than the sixth value, ρ 0.65 The flare angle is less than the preset angle and the value is greater than the seventh value. The sixth and seventh values ​​can both be 0.3, and the preset angle can be 40°. The processor can also confirm that a suspected ignition point is caused by clouds if the apparent reflectivity and apparent brightness temperature meet any of the following conditions: Condition 1 is: at ρ... 0.86 With ρ 0.65 When the sum is greater than the eighth value, the apparent brightness temperature in the mid-infrared band within the wavelength range of (12±0.05) μm is less than the first temperature. Condition 2 is that in ρ 0.86 With ρ 0.65 If the sum of the values ​​is greater than the ninth value and less than or equal to the eighth value, the apparent brightness temperature in the mid-infrared band within the wavelength range of (12±0.05) μm is greater than or equal to the first temperature and less than the second temperature. If either condition 1 or condition 2 is met, the suspected ignition point at the target location is determined to be caused by clouds. Here, the eighth value can be 0.9, the ninth value can be 0.7, the first temperature can be 265K, and the second temperature can be 285K. Once the processor confirms that the suspected ignition point is not caused by any of the three types of interference mentioned above, it confirms that a fire has occurred at the target location.

[0054] Using the methods described above, this application can acquire multi-band infrared remote sensing images from high-resolution satellites and meteorological satellites to determine whether a fire point exists at the target location. Compared to traditional meteorological satellite identification methods, this application utilizes high-resolution short-wave and near-wave infrared remote sensing images acquired by high-resolution satellites, resulting in higher resolution and more accurate fire point identification, preventing small-area wildfires from being missed. Furthermore, this application eliminates several possibilities that could interfere with the processor's judgment, thus improving identification accuracy.

[0055] Figure 1 This is a flowchart illustrating a method for identifying wildfire ignition points based on high-resolution satellite remote sensing imagery in one embodiment. It should be understood that, although... Figure 1The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0056] In one embodiment, such as Figure 2 As shown, a wildfire ignition point location identification device 200 based on high-resolution satellite remote sensing imagery is provided, including a remote sensing image acquisition module 201, a suspected ignition point confirmation module 202, and an interference elimination module 203, wherein:

[0057] The remote sensing image acquisition module 201 is used to acquire remote sensing images of the target location in multiple bands at the current time.

[0058] The suspected ignition point confirmation module 202 is used to determine the normalized combustion index of remote sensing images based on the apparent emissivity of remote sensing images under multiple bands; determine the apparent reflectivity and corresponding apparent brightness temperature of remote sensing images that meet multiple wavelength conditions respectively; and determine the target location as a suspected ignition point when the normalized combustion index meets the first preset condition and / or the apparent reflectivity and apparent brightness temperature simultaneously meet the second preset condition.

[0059] The interference elimination module 203 is used to eliminate interference data from suspected fire points in order to determine whether a fire has actually occurred at the target location.

[0060] The wildfire ignition point location identification device based on high-resolution satellite remote sensing imagery includes a processor and a memory. The aforementioned remote sensing image acquisition module, suspected ignition point confirmation module, and interference elimination module are all stored as program units in the memory. The processor executes the aforementioned program modules stored in the memory to implement the corresponding functions.

[0061] The processor contains a kernel, which retrieves the corresponding program units from memory. One or more kernels can be configured, and adjusting kernel parameters enables methods for identifying wildfire ignition points based on high-resolution satellite remote sensing imagery.

[0062] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0063] This application provides a storage medium storing a program that, when executed by a processor, implements the above-described method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing images.

[0064] This application provides a processor for running a program, wherein the program executes the above-described method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing images.

[0065] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 3 As shown. The computer device includes a processor A01, a network interface A02, memory (not shown), and a database (not shown) connected via a system bus. The processor A01 provides computing and control capabilities. The memory includes internal memory A03 and a non-volatile storage medium A04. The non-volatile storage medium A04 stores an operating system B01, a computer program B02, and a database (not shown). The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 stored in the non-volatile storage medium A04. The network interface A02 is used for communication with external terminals via a network connection. When the computer program B02 is executed by the processor A01, it implements a method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery.

[0066] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0067] In one embodiment, the wildfire ignition point location identification device based on high-resolution satellite remote sensing imagery provided in this application can be implemented as a computer program, which can be implemented in, for example... Figure 3The device operates on the computer shown. The computer's memory can store various program modules that make up the wildfire ignition point location identification device based on high-resolution satellite remote sensing imagery. The computer program, composed of these program modules, causes the processor to execute the steps in the wildfire ignition point location identification method based on high-resolution satellite remote sensing imagery of the various embodiments of this application described in this specification.

[0068] This application provides an apparatus including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs the following steps: acquiring remote sensing images of a target location at the current time across multiple wavelengths; determining the normalized ignition index (NDI) of the remote sensing images based on their apparent emissivity across the multiple wavelengths; determining the apparent reflectivity and corresponding apparent brightness temperature of the remote sensing images that satisfy multiple wavelength conditions; determining the target location as a suspected ignition point if the NDI satisfies a first preset condition and / or if both the apparent reflectivity and apparent brightness temperature satisfy a second preset condition; and eliminating interference data from the suspected ignition point to determine whether a fire has actually occurred at the target location.

[0069] In one embodiment, determining the normalized burn index of a remote sensing image based on its apparent emissivity across multiple bands includes: determining the normalized burn index according to formula (1):

[0070]

[0071] Where NBRS is the normalized combustion index, ρ 0.86 ρ refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. 1.6 This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 1.6 μm is within a second preset range, ρ. 2.1 It refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 2.1μm is within the third preset range, and k is a preset coefficient; the first preset condition refers to the normalized combustion index being within the preset ignition point identification range.

[0072] In one embodiment, apparent reflectance and apparent brightness temperature are determined to simultaneously meet a second preset condition if all of the following conditions are met: the first apparent reflectance is greater than a first threshold; the average difference between the first apparent reflectance and the historical apparent reflectance for each day within a preset historical time period is greater than a second threshold; the ratio of the second apparent reflectance to the first apparent reflectance is less than a first value; and the difference between the first apparent brightness temperature and the second apparent brightness temperature is greater than a second value. Wherein, the first apparent reflectance refers to the apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within a fourth preset range, and the first threshold refers to the maximum historical data value of 7 for apparent reflectance in the mid-wave infrared band where the difference between the wavelength and 4μm is within a fourth preset range. The percentage value refers to the average apparent reflectance of the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm on day (ti). The second threshold refers to 7% of the maximum historical difference in apparent reflectance data for the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm. The second apparent reflectance refers to the apparent reflectance of the short-wave infrared band within the second preset range for wavelength differences of 1.6μm. The first apparent brightness temperature refers to the apparent brightness temperature of the mid-wave infrared band within the fourth preset range for wavelength differences of 4μm, in K. The second apparent brightness temperature refers to the apparent brightness temperature of the mid-wave infrared band within the fifth preset range for wavelength differences of 11μm, in K.

[0073] In one embodiment, excluding interfering data from suspected fire points includes excluding suspected fire points caused by any one of water bodies, solar flares, or clouds.

[0074] In one embodiment, a suspected ignition point is confirmed to be caused by water if the apparent reflectance simultaneously meets all of the following conditions: the third apparent reflectance is less than the third value; the fourth apparent reflectance is less than the fourth value; the ratio between the difference between the fourth and fifth apparent reflectances and the sum of the fourth and fifth apparent reflectances is less than the fifth value; wherein, the third apparent reflectance refers to the apparent reflectance of the shortwave infrared band where the difference between the wavelength and 2.1 μm is within a third preset range, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range.

[0075] In one embodiment, the method further includes: acquiring the observed zenith angle, solar altitude angle, and relative azimuth angle of the target location at the current moment; determining the flare angle of the target location at the current moment based on the observed zenith angle, solar altitude angle, and relative azimuth angle; confirming that the suspected ignition point is caused by a flare when the apparent reflectance simultaneously meets all of the following conditions: the fourth apparent reflectance is greater than the sixth value; the fifth apparent reflectance is greater than the seventh value; and the flare angle is less than a preset angle; wherein, the fourth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range, and the fifth apparent reflectance refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range.

[0076] In one embodiment, a suspected ignition point is confirmed to be caused by clouds if the apparent reflectance meets any of the following conditions: the sum of the fourth and fifth apparent reflectances is greater than the eighth value, and the third apparent brightness temperature is less than the first temperature; or the sum of the fourth and fifth apparent reflectances is greater than the ninth value and less than or equal to the eighth value, and the third apparent brightness temperature is greater than or equal to the first temperature and less than the second temperature. Wherein, the fourth apparent reflectance refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range; the fifth apparent reflectance refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.65 μm is within a sixth preset range; and the third apparent brightness temperature refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 12 μm is within a seventh preset range, with units in K.

[0077] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0078] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0079] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0080] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0081] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0082] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0083] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0084] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0085] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for identifying the location of wildfire ignition points based on high-resolution satellite remote sensing imagery, characterized in that, The method includes: Acquire remote sensing images of the target location in multiple bands at the current time; The normalized combustion index of the remote sensing image is determined based on the apparent emissivity of the remote sensing image under multiple bands. Determine the apparent reflectance and corresponding apparent brightness temperature of remote sensing images that satisfy multiple wavelength conditions. If the normalized flammability index meets the first preset condition and / or the apparent reflectance and the apparent brightness temperature simultaneously meet the second preset condition, the target location is determined to be a suspected ignition point. Interference data is eliminated from the suspected fire points to determine whether a fire has actually occurred at the target location. The determination of the normalized combustion index of the remote sensing image based on the apparent emissivity of the remote sensing image across the multiple bands includes: The normalized flammability index is determined according to formula (1): NBRS= Formula (1); Wherein, NBRS is the normalized flammability index. This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. This refers to the apparent reflectivity of the shortwave infrared band where the difference between the wavelength and 1.6μm is within a second preset range. It refers to the apparent reflectivity of the short-wave infrared band where the difference between the wavelength and 2.1μm is within the third preset range, and k is a preset coefficient; The first preset condition refers to the normalized combustion index being within the preset ignition point identification range; Under the condition that all of the following conditions are met, it is determined that the apparent reflectivity and the apparent luminance temperature simultaneously satisfy the second preset condition: First apparent reflectance Greater than the first threshold ; First apparent reflectance Historical apparent reflectance for each day within a preset historical time period The mean of the differences is greater than the second threshold. ; Second apparent reflectance Compared with the first apparent reflectivity The ratio is less than the first value; First apparent brightness temperature With the second apparent brightness temperature The difference is greater than the second value; Wherein, the first apparent reflectance This refers to the apparent reflectance in the mid-infrared band where the difference between the wavelength and 4μm is within a fourth preset range, and the first threshold. This refers to 7% of the historical maximum value of apparent reflectance data in the mid-infrared band where the difference between the wavelength and 4μm is within the fourth preset range. The historical apparent reflectance... This refers to the average apparent reflectance in the mid-infrared band of days (ti) with a wavelength difference of 4 μm within the fourth preset range, and the second threshold. This refers to a value where the difference between the wavelength and 4μm falls within 7% of the maximum historical difference in apparent reflectance data for the mid-infrared band within the fourth preset range. The second apparent reflectance... This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 1.6 μm is within a second preset range, and the first apparent brightness temperature... This refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 4μm is within the fourth preset range, expressed in Kelvin. The second apparent brightness temperature... It refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 11μm is within the fifth preset range, and the unit is K.

2. The method according to claim 1, characterized in that, Data interference removal for the suspected fire points includes: The suspected ignition point was ruled out as being caused by any of the following: water, solar flares, or clouds.

3. The method according to claim 2, characterized in that, If the apparent reflectance simultaneously meets all of the following conditions, the suspected ignition point is confirmed to be caused by water. Third apparent reflectance Less than the third value; Fourth apparent reflectance Less than the fourth value; The fourth apparent reflectance With the fifth apparent reflectance The difference between the fourth apparent reflectance and the With the fifth apparent reflectance The ratio between the sum and the value is less than the fifth value; Among them, the third apparent reflectance This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 2.1 μm is within a third preset range. The fourth apparent reflectance... This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. The fifth apparent reflectance... It refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65μm is within the sixth preset range.

4. The method according to claim 2, characterized in that, The method further includes: Obtain the observed zenith angle, solar altitude angle, and relative azimuth angle of the target location at the current moment; The flare angle at the current time of the target position is determined based on the observed zenith angle, the solar altitude angle, and the relative azimuth angle. If the apparent reflectivity simultaneously meets all of the following conditions, the suspected ignition point is confirmed to be caused by a flare; Fourth apparent reflectance Greater than the sixth value; Fifth apparent reflectance Greater than the seventh value; The flare angle is less than a preset angle; Among them, the fourth apparent reflectance This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. The fifth apparent reflectance... It refers to the apparent reflectance of the near-infrared band where the difference between the wavelength and 0.65μm is within the sixth preset range.

5. The method according to claim 2, characterized in that, If the apparent reflectance meets any of the following conditions, the suspected ignition point is confirmed to be caused by clouds; Fourth apparent reflectance With the fifth apparent reflectance The sum is greater than the eighth value, and the third apparent brightness temperature Less than the first temperature; The fourth apparent reflectance With the fifth apparent reflectance The sum of the values ​​is greater than the ninth value and less than or equal to the eighth value, and the third apparent brightness temperature Greater than or equal to the first temperature and less than the second temperature; Among them, the fourth apparent reflectance This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. The fifth apparent reflectance... This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.65μm is within the sixth preset range, and the third apparent brightness temperature... It refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 12μm is within the seventh preset range, and the unit is K.

6. A processor, characterized in that, Configured to perform the method according to any one of claims 1 to 5.

7. A wildfire ignition point identification device based on high-resolution satellite remote sensing imagery, characterized in that, The device includes: The remote sensing image acquisition module is used to acquire remote sensing images of the target location in multiple bands at the current time. A suspected fire point confirmation module is used to determine the normalized combustion index of the remote sensing image based on the apparent emissivity of the remote sensing image under multiple bands; determine the apparent reflectivity and corresponding apparent brightness temperature of the remote sensing image that respectively meet multiple wavelength conditions; and determine the target location as a suspected fire point when the normalized combustion index meets a first preset condition and / or the apparent reflectivity and apparent brightness temperature simultaneously meet a second preset condition; and an interference elimination module is used to eliminate interference data from the suspected fire point to determine whether a fire has actually occurred at the target location. The determination of the normalized combustion index of the remote sensing image based on the apparent emissivity of the remote sensing image across the multiple bands includes: The normalized flammability index is determined according to formula (1): NBRS= Formula (1); Wherein, NBRS is the normalized flammability index. This refers to the apparent reflectance in the near-infrared band where the difference between the wavelength and 0.86 μm is within a first preset range. This refers to the apparent reflectivity of the shortwave infrared band where the difference between the wavelength and 1.6μm is within a second preset range. It refers to the apparent reflectivity of the short-wave infrared band where the difference between the wavelength and 2.1μm is within the third preset range, and k is a preset coefficient; The first preset condition refers to the normalized combustion index being within the preset ignition point identification range; Under the condition that all of the following conditions are met, it is determined that the apparent reflectivity and the apparent luminance temperature simultaneously satisfy the second preset condition: First apparent reflectance Greater than the first threshold ; First apparent reflectance Historical apparent reflectance for each day within a preset historical time period The mean of the differences is greater than the second threshold. ; Second apparent reflectance Compared with the first apparent reflectivity The ratio is less than the first value; First apparent brightness temperature With the second apparent brightness temperature The difference is greater than the second value; Wherein, the first apparent reflectance This refers to the apparent reflectance in the mid-infrared band where the difference between the wavelength and 4μm is within a fourth preset range, and the first threshold. This refers to 7% of the historical maximum value of apparent reflectance data in the mid-infrared band where the difference between the wavelength and 4μm is within the fourth preset range. The historical apparent reflectance... This refers to the average apparent reflectance in the mid-infrared band of days (ti) with a wavelength difference of 4 μm within the fourth preset range, and the second threshold. This refers to a value where the difference between the wavelength and 4μm falls within 7% of the maximum historical difference in apparent reflectance data for the mid-infrared band within the fourth preset range. The second apparent reflectance... This refers to the apparent reflectance of the short-wave infrared band where the difference between the wavelength and 1.6 μm is within a second preset range, and the first apparent brightness temperature... This refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 4μm is within the fourth preset range, expressed in Kelvin. The second apparent brightness temperature... It refers to the apparent brightness temperature in the mid-infrared band where the difference between the wavelength and 11μm is within the fifth preset range, and the unit is K.

8. A machine-readable storage medium storing instructions thereon, characterized in that, When executed by a processor, this instruction causes the processor to be configured to perform the method according to any one of claims 1 to 5.

Images