Fixed star irradiance calculation method and device based on measured data

Abstract

The invention provides a fixed star irradiance calculation method and device based on measured data. The method comprises the following steps: respectively determining a target area and a background area in each frame of infrared radiation image by using a connected domain method; respectively calculating the signal-to-noise ratio of each frame of infrared radiation image and setting a signal-to-noise ratio threshold value based on the gray values of the target region and the background region; the infrared radiation images with the signal-to-noise ratios smaller than a signal-to-noise ratio threshold value are removed, and a plurality of frames of screened infrared radiation images are obtained; based on the instantaneous field angle and the calibration coefficient of the detector, calculating the radiation illumination mean value and the standard deviation of the plurality of frames of infrared radiation images after screening, and determining the fixed star radiation illumination under the current detection wave band based on the radiation illumination mean value and the standard deviation; according to the current meteorological parameters of the detector, the fixed star irradiance under the current detection wave band and the star catalogue database, the fixed star irradiance under any detection wave band is reversely calculated. According to the scheme, the infrared fixed star irradiance backstepping calculation of any required wave band can be realized.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of stellar energy measurement, and in particular to a method and device for calculating stellar radiation illumination based on measured data. Background Art

[0002] The ground-based optical system can perform long-term and repeated measurements of stars due to its repeatable measurement advantages. However, it is difficult to obtain stellar radiation spectrum data due to atmospheric disturbances and attenuation, and can only obtain radiation data in several specific bands of the atmospheric window. The spaceborne optical system avoids the influence of the atmosphere on radiation measurement and can perform spectral observations of stars. However, due to the limitations of the orbit and refrigerants, only a limited number of measurements can be made on stars. For stars with changing radiation, long-term observations cannot be made, and the study of the changing laws of stellar radiation characteristics cannot be supported.

[0003] Therefore, there is an urgent need to provide a method and device for calculating stellar radiation based on measured data. Summary of the invention

[0004] In order to solve the problem that traditional satellite-borne optical systems cannot achieve long-term observation of stars with changing radiation, an embodiment of the present invention provides a method and device for calculating stellar radiation illumination based on measured data.

[0005] In a first aspect, an embodiment of the present invention provides a method for calculating stellar radiance based on measured data, the method comprising:

[0006] Obtain several frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector;

[0007] The connected domain method is used to determine the target area and background area in each frame of infrared radiation image.

[0008] Based on the grayscale values ​​of the target area and the background area, respectively calculating the signal-to-noise ratio of each frame of the infrared radiation image and setting a signal-to-noise ratio threshold;

[0009] Eliminate infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold to obtain a plurality of frames of filtered infrared radiation images;

[0010] Based on the instantaneous field of view angle of the detector and the calibration coefficient, the mean value and standard deviation of the radiance of the selected frames of infrared radiation images are calculated, and the stellar radiance in the current detection band is determined based on the mean value and standard deviation of the radiance;

[0011] The stellar radiance in any detection band is calculated in reverse according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database.

[0012] In a second aspect, an embodiment of the present invention further provides a stellar radiance calculation device based on measured data, the device comprising:

[0013] An acquisition unit is used to acquire several frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector;

[0014] A division unit, used for dividing the target area and the background area in each frame of infrared radiation image by using a connected domain method;

[0015] A first calculation unit, used to calculate the signal-to-noise ratio of each frame of infrared radiation image based on the grayscale values ​​of the target area and the background area and set a signal-to-noise ratio threshold;

[0016] A screening unit, used to remove infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold, to obtain a plurality of frames of screened infrared radiation images;

[0017] A determination unit, configured to calculate the mean and standard deviation of the radiance of the selected infrared radiation images based on the instantaneous field of view of the detector and the calibration coefficient, and determine the stellar radiance in the current detection band based on the mean and standard deviation of the radiance;

[0018] The second calculation unit is used to reversely calculate the stellar radiance in any detection band according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database.

[0019] In a third aspect, an embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method described in any embodiment of this specification is implemented.

[0020] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute the method described in any embodiment of this specification.

[0021] On the other hand, an embodiment of the present application further provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes any of the methods described in the above embodiments.

[0022] The embodiment of the present invention provides a method for calculating the stellar radiance based on measured data. First, the connected domain method is used to divide each frame of infrared radiation image obtained into a target area and a background area, and the signal-to-noise ratio of each frame of infrared radiation image is calculated according to the grayscale values ​​of the target area and the background area. After that, each frame of infrared radiation image is screened according to the signal-to-noise ratio threshold to obtain a screened radiation image to improve the accuracy of subsequent radiation image calculations. The infrared radiation image is then screened again by the radiance mean and standard deviation of several frames of infrared radiation images after screening, so as to determine the stellar radiance under the final detection band. Finally, based on the radiance and the star catalog data of the satellite-borne test system, the stellar radiance under any detection band can be inferred. In this way, the present invention can realize the inverse calculation of infrared stellar radiance in any required band without adding detectors of ground or air measurement equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 is a flow chart of a method for calculating stellar radiance based on measured data provided by one embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of a target area and a background area in a frame of infrared radiation image provided by an embodiment of the present invention;

[0026] Figure 3 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0027] Figure 4 It is a structural diagram of a stellar radiance calculation device based on measured data provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] The specific implementation of the above concept is described below.

[0030] Please refer to Figure 1 The embodiment of the present invention provides a method for calculating stellar radiance based on measured data, the method comprising:

[0031] Step 100, obtaining a plurality of frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector;

[0032] Step 102, using a connected domain method to respectively determine the target area and the background area in each frame of infrared radiation image;

[0033] Step 104, based on the grayscale values ​​of the target area and the background area, respectively calculate the signal-to-noise ratio of each frame of the infrared radiation image and set a signal-to-noise ratio threshold;

[0034] Step 106, eliminating infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold, to obtain a plurality of frames of filtered infrared radiation images;

[0035] Step 108, based on the instantaneous field of view of the detector and the calibration coefficient, the mean value and standard deviation of the radiance of the selected infrared radiation images are calculated, and the stellar radiance in the current detection band is determined based on the mean value and standard deviation of the radiance;

[0036] Step 110, based on the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database, reversely calculate the stellar radiance in any detection band.

[0037] In the embodiment of the present invention, the connected domain method is first used to divide each frame of infrared radiation image obtained into a target area and a background area, and the signal-to-noise ratio of each frame of infrared radiation image is calculated according to the grayscale values ​​of the target area and the background area. After that, each frame of infrared radiation image is screened according to the signal-to-noise ratio threshold to obtain a screened radiation image to improve the accuracy of subsequent radiation image calculations. The infrared radiation image is then screened again by the mean and standard deviation of the radiation illuminance of several frames of infrared radiation images after screening, so as to determine the stellar radiation illuminance under the final detection band. Finally, based on the radiation illuminance and the star catalog data of the satellite-borne test system, the stellar radiation illuminance under any detection band can be inferred. In this way, the present invention can realize the infrared stellar radiation illuminance calculation of the required band without adding detectors of ground or air measurement equipment.

[0038] For step 100:

[0039] In an embodiment of the present invention, a ground or airborne detector measures a certain infrared star to obtain m-frame sequence images at a certain detection angle and detection band, and simultaneously records meteorological parameters such as temperature, humidity, pressure, wind speed, elevation angle and altitude of the current detector.

[0040] Regarding step 102:

[0041] In some embodiments, for each frame of infrared radiation image, the target area and the background area are determined in the following manner:

[0042] Select a frame near the star point source in the infrared radiation image to obtain a framed area;

[0043] Calculating the grayscale mean and standard deviation of the framed area respectively, and setting a first threshold value based on the grayscale mean and standard deviation;

[0044] Based on the first threshold and the framed area, a target area and a background area are respectively determined using a connected domain method.

[0045] In the embodiment of the present invention, a single frame infrared radiation image is taken as an example. Figure 1 As shown, firstly, a box is selected near the star power source to obtain the box selection area M, and the grayscale mean of the image in the box selection area M is calculated. and standard deviation S, and the first threshold DN1 is set with the grayscale mean and standard deviation. The target area m is determined by the connected domain method using the first threshold, and the background area n is Mm.

[0046] Regarding step 104 and step 106:

[0047] In some implementations, step 104 includes:

[0048] Calculating the grayscale value of each pixel in the target area and determining the maximum grayscale value in the target area;

[0049] Calculating the grayscale mean of the background area;

[0050] The signal-to-noise ratio of the infrared radiation image is calculated based on the grayscale maximum value in the target area and the grayscale mean value in the background area.

[0051] In the embodiment of the present invention, the maximum grayscale value in the target area is DN max , the grayscale mean of the background area is DN back , so the signal-to-noise ratio (SNR) of each frame of infrared radiation image can be calculated by the following formula:

[0052]

[0053] Afterwards, each frame of infrared radiation image is screened, and infrared radiation images with a signal-to-noise ratio less than a signal-to-noise ratio threshold (for example, the signal-to-noise ratio threshold is 3) are eliminated to obtain several frames of infrared radiation images after screening, which is conducive to improving the calculation accuracy of subsequent stellar radiation illumination.

[0054] Regarding step 108:

[0055] In some embodiments, step 108 includes:

[0056] Convert the grayscale value of each pixel in the framed area based on the calibration coefficient to obtain the radiant brightness value of each pixel in the framed area;

[0057] Calculate the average radiance in the background area, and calculate the total radiance in the target area based on the average radiance and the radiance value of each pixel in the selected area;

[0058] Calculating the radiant illumination of each frame of the filtered infrared radiation image based on the total value of the radiant brightness in the target area and the instantaneous field of view of the detector;

[0059] According to the radiance of each frame of infrared radiation image, the mean and standard deviation of the radiance of several frames of infrared radiation images after screening are calculated.

[0060] In the embodiment of the present invention, for each frame of infrared radiation image after screening, the following formula is first used to perform grayscale conversion on each pixel point in the frame selection area M:

[0061] L ij =DN ij k+c

[0062] Where, L ij is the radiance value of each pixel in the selected area M, DN ij is the grayscale value of each pixel in the selected area M, i is the row number of the pixel, j is the column number of the pixel, and k and c are calibration coefficients obtained by the laboratory through blackbody radiation calibration.

[0063] Afterwards, the total radiation brightness L in the target area is calculated by the following formula: star :

[0064] L star =∑(L ij -L back )

[0065] Where, L back is the mean radiance of the background area n.

[0066] Finally, according to formula E star =L back Ω, where Ω is the detection field angle of the detector, from which the radiance of each frame of infrared radiation image can be calculated, and the average radiance of several frame sequence images after screening can be calculated and standard deviation S star .

[0067] In some embodiments, the stellar radiance in the current detection band is determined by:

[0068] Based on the irradiance mean and standard deviation, setting a second threshold;

[0069] Compare the radiant illumination of each frame of the screened infrared radiation image with the second threshold value, and retain the infrared radiation images that do not exceed the second threshold value to obtain the infrared radiation image after secondary screening;

[0070] The average stellar radiance of several frames of infrared radiation images after secondary screening is calculated, and the average stellar radiance is determined as the stellar radiance in the current detection band.

[0071] In the embodiment of the present invention, the second threshold is set using the mean value and standard deviation of the irradiance. The infrared radiation image with radiance within the second threshold range is retained, and the radiance mean of the retained infrared radiation image is used as the stellar radiance E in the current detection band. stars In this way, the filtered infrared radiation image is screened again using the second threshold, which is beneficial to further enhance the calculation accuracy of the stellar radiation illumination.

[0072] Regarding step 110:

[0073] In some preferred embodiments, step 110 includes:

[0074] Using the current meteorological parameters of the detector as input parameters, the atmospheric transmittance on the detection path is calculated using atmospheric radiation calculation software;

[0075] Determine the spectrum type of the currently measured star according to the star catalog database;

[0076] Based on the spectrum type and the spectrum template, the radiation flux of the current detection band and the band to be measured are obtained respectively, and the radiation flux ratio of the two bands is calculated;

[0077] The stellar radiance in the band to be measured is obtained by reverse calculation based on the stellar radiance in the current detection band, the atmospheric transmittance and the radiation flux ratio.

[0078] In an embodiment of the present invention, assuming that the detection band of the current detector is 1 and the band to be measured is 2, the spectral type (for example, type O) of the currently measured star can be determined from the star catalog data released by the satellite-borne measurement system, and the radiation fluxes f1 and f2 of the detection band 1 and the band to be measured can be further queried according to the spectral type and the spectral template, respectively, and the radiation flux ratio c=f1 / f2 of the two can be obtained thereby. Therefore, without adding detectors to ground or air measurement equipment, the stellar radiation illumination in any band can be inferred based on the inverse calculation.

[0079] In some preferred embodiments, the stellar radiance in the measured band includes the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere; wherein the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere are calculated by the following formulas respectively:

[0080]

[0081] In the formula, E m is the stellar radiance in the atmosphere under the measured band, E stars is the stellar irradiance in the current detection band, c is the radiation flux ratio, E m' is the stellar radiation illumination outside the atmosphere in the band to be measured, and τ is the atmospheric transmittance on the detection path.

[0082] like Figure 3 , Figure 4 As shown, an embodiment of the present invention provides a device for calculating stellar radiance based on measured data. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 3 As shown in FIG. 1 , a hardware architecture diagram of a computing device in which a stellar radiance calculation device based on measured data is provided in an embodiment of the present invention includes Figure 4 In addition to the processor, memory, network interface, and non-volatile memory shown in the figure, the computing device in which the device is located in the embodiment may also generally include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 4 As shown, as a device in a logical sense, the CPU of the computing device in which it is located reads the corresponding computer program in the non-volatile memory into the internal memory and runs it.

[0083] This embodiment provides a device for calculating stellar radiance based on measured data, the device comprising:

[0084] The acquisition unit 401 is used to acquire a plurality of frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector;

[0085] A division unit 402 is used to divide the target area and the background area in each frame of infrared radiation image by using a connected domain method;

[0086] A first calculation unit 403, used to calculate the signal-to-noise ratio of each frame of infrared radiation image based on the grayscale values ​​of the target area and the background area and set a signal-to-noise ratio threshold;

[0087] A screening unit 404 is used to remove infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold, to obtain a plurality of frames of screened infrared radiation images;

[0088] The determination unit 405 is used to calculate the mean and standard deviation of the radiance of the selected infrared radiation images based on the instantaneous field of view of the detector and the calibration coefficient, and determine the stellar radiance in the current detection band based on the mean and standard deviation of the radiance;

[0089] The second calculation unit 406 is used to reversely calculate the stellar radiance in any detection band according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database.

[0090] In an embodiment of the present invention, the acquisition unit 401 can be used to execute step 100 in the above method embodiment, the division unit 402 can be used to execute step 102 in the above method embodiment, the first calculation unit 403 can be used to execute step 104 in the above method embodiment, the screening unit 404 can be used to execute step 106 in the above method embodiment, the determination unit 405 can be used to execute step 108 in the above method embodiment, and the second calculation unit 406 can be used to execute step 110 in the above method embodiment.

[0091] In one embodiment of the present invention, in the division unit 402, for each frame of infrared radiation image, the target area and the background area are determined in the following manner:

[0092] Select a frame near the star point source in the infrared radiation image to obtain a framed area;

[0093] Calculating the grayscale mean and standard deviation of the framed area respectively, and setting a first threshold value based on the grayscale mean and standard deviation;

[0094] Based on the first threshold and the framed area, a target area and a background area are respectively determined using a connected domain method.

[0095] In one embodiment of the present invention, when the first calculation unit 403 calculates the signal-to-noise ratio of each frame of infrared radiation image based on the grayscale values ​​of the target area and the background area, respectively, it is used to perform the following operations:

[0096] Calculating the grayscale value of each pixel in the target area and determining the maximum grayscale value in the target area;

[0097] Calculating the grayscale mean of the background area;

[0098] The signal-to-noise ratio of the infrared radiation image is calculated based on the grayscale maximum value in the target area and the grayscale mean value in the background area.

[0099] In one embodiment of the present invention, the screening unit 404 is used to perform the following operations when calculating the mean and standard deviation of the radiant illumination of the screened frames of infrared radiation images based on the instantaneous field of view of the detector and the calibration coefficient:

[0100] Convert the grayscale value of each pixel in the framed area based on the calibration coefficient to obtain the radiant brightness value of each pixel in the framed area;

[0101] Calculate the average radiance in the background area, and calculate the total radiance in the target area based on the average radiance and the radiance value of each pixel in the selected area;

[0102] Calculating the radiant illumination of each frame of the filtered infrared radiation image based on the total value of the radiant brightness in the target area and the instantaneous field of view of the detector;

[0103] According to the radiance of each frame of infrared radiation image, the mean and standard deviation of the radiance of several frames of infrared radiation images after screening are calculated.

[0104] In one embodiment of the present invention, when determining the stellar radiance in the current detection band based on the radiance mean and standard deviation, the determination unit 405 is used to perform the following operations:

[0105] Based on the irradiance mean and standard deviation, setting a second threshold;

[0106] Compare the radiant illumination of each frame of the screened infrared radiation image with the second threshold value, and retain the infrared radiation images that do not exceed the second threshold value to obtain the infrared radiation image after secondary screening;

[0107] The average stellar radiance of several frames of infrared radiation images after secondary screening is calculated, and the average stellar radiance is determined as the stellar radiance in the current detection band.

[0108] In one embodiment of the present invention, the second calculation unit 406 is used to perform the following operations when reversely calculating the stellar radiance in any detection band according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database:

[0109] Using the current meteorological parameters of the detector as input parameters, the atmospheric transmittance on the detection path is calculated using atmospheric radiation calculation software;

[0110] Determine the spectrum type of the currently measured star according to the star catalog database;

[0111] Based on the spectrum type and the spectrum template, the radiation flux of the current detection band and the band to be measured are obtained respectively, and the radiation flux ratio of the two bands is calculated;

[0112] The stellar radiance in the band to be measured is obtained by reverse calculation based on the stellar radiance in the current detection band, the atmospheric transmittance and the radiation flux ratio.

[0113] In one embodiment of the present invention, in the second calculation unit 406, the stellar radiance in the measured band includes the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere; wherein the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere are calculated by the following formulas respectively:

[0114]

[0115] In the formula, E m is the stellar radiance in the atmosphere under the measured band, E stars is the stellar irradiance in the current detection band, c is the radiation flux ratio, E m' is the stellar radiation illumination outside the atmosphere in the band to be measured, and τ is the atmospheric transmittance on the detection path.

[0116] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a stellar irradiance calculation device based on measured data. In other embodiments of the present invention, a stellar irradiance calculation device based on measured data may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0117] The information interaction, execution process and other contents between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0118] An embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a method for calculating stellar radiation illumination based on measured data in any embodiment of the present invention is implemented.

[0119] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor executes a method for calculating stellar radiation illumination based on measured data in any embodiment of the present invention.

[0120] Specifically, a system or device equipped with a storage medium can be provided, on which software program code that implements the functions of any of the above-mentioned embodiments is stored, and a computer (or CPU or MPU) of the system or device can be enabled to read and execute the program code stored in the storage medium.

[0121] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute a part of the present invention.

[0122] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

[0123] In addition, it should be clear that the functions of any of the above embodiments can be implemented not only by executing the program code read by the computer, but also by enabling an operating system operating on the computer to complete part or all of the actual operations based on instructions from the program code.

[0124] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above-mentioned embodiments.

[0125] An embodiment of the present application also provides a computer-readable storage medium, on which is stored at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor to implement a method for calculating stellar radiation illumination based on measured data provided in the above-mentioned method embodiments.

[0126] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0127] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating stellar irradiance based on measured data, characterized in that: include: Obtain several frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector; The connected domain method is used to determine the target area and background area in each frame of infrared radiation image. Based on the grayscale values ​​of the target area and the background area, respectively calculating the signal-to-noise ratio of each frame of the infrared radiation image and setting a signal-to-noise ratio threshold; Eliminate infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold to obtain a plurality of frames of filtered infrared radiation images; Based on the instantaneous field of view angle of the detector and the calibration coefficient, the mean value and standard deviation of the radiance of the selected frames of infrared radiation images are calculated, and the stellar radiance in the current detection band is determined based on the mean value and standard deviation of the radiance; The stellar radiance in any detection band is calculated in reverse according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database.

2. The method according to claim 1, characterized in that For each frame of infrared radiation image, the target area and background area are determined in the following way: Select a frame near the star point source in the infrared radiation image to obtain a framed area; Calculating the grayscale mean and standard deviation of the framed area respectively, and setting a first threshold value based on the grayscale mean and standard deviation; Based on the first threshold and the framed area, a target area and a background area are respectively determined using a connected domain method.

3. The method according to claim 1, characterized in that The step of calculating the signal-to-noise ratio of each frame of infrared radiation image based on the grayscale values ​​of the target area and the background area includes: Calculating the grayscale value of each pixel in the target area and determining the maximum grayscale value in the target area; Calculating the grayscale mean of the background area; The signal-to-noise ratio of the infrared radiation image is calculated based on the grayscale maximum value in the target area and the grayscale mean value in the background area.

4. The method according to claim 2, characterized in that: The step of calculating the mean and standard deviation of the radiant illumination of the selected infrared radiation images based on the instantaneous field of view of the detector and the calibration coefficient includes: Convert the grayscale value of each pixel in the framed area based on the calibration coefficient to obtain the radiant brightness value of each pixel in the framed area; Calculate the average radiance in the background area, and calculate the total radiance in the target area based on the average radiance and the radiance value of each pixel in the selected area; Calculating the radiant illumination of each frame of the filtered infrared radiation image based on the total value of the radiant brightness in the target area and the instantaneous field of view of the detector; According to the radiance of each frame of infrared radiation image, the mean and standard deviation of the radiance of several frames of infrared radiation images after screening are calculated.

5. The method according to claim 4, characterized in that The step of determining the stellar radiance in the current detection band based on the radiance mean and standard deviation includes: Based on the irradiance mean and standard deviation, setting a second threshold; Compare the radiant illumination of each frame of the screened infrared radiation image with the second threshold value, and retain the infrared radiation images that do not exceed the second threshold value to obtain the infrared radiation image after secondary screening; The average stellar radiance of several frames of infrared radiation images after secondary screening is calculated, and the average stellar radiance is determined as the stellar radiance in the current detection band.

6. The method according to any one of claims 1 to 5, characterized in that The reverse calculation of the stellar radiance in any detection band according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database includes: Using the current meteorological parameters of the detector as input parameters, the atmospheric transmittance on the detection path is calculated using atmospheric radiation calculation software; Determine the spectrum type of the currently measured star according to the star catalog database; Based on the spectrum type and the spectrum template, the radiation flux of the current detection band and the band to be measured are obtained respectively, and the radiation flux ratio of the two bands is calculated; The stellar radiance in the band to be measured is obtained by reverse calculation based on the stellar radiance in the current detection band, the atmospheric transmittance and the radiation flux ratio.

7. The method according to claim 6, characterized in that The stellar radiance in the measured band includes the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere; wherein the stellar radiance in the atmosphere and the stellar radiance outside the atmosphere are calculated by the following formulas respectively: In the formula, E m is the stellar radiance in the atmosphere under the measured band, E stars is the stellar irradiance in the current detection band, c is the radiation flux ratio, E m' is the stellar radiation illumination outside the atmosphere in the band to be measured, and τ is the atmospheric transmittance on the detection path.

8. A device for calculating stellar radiance based on measured data, characterized in that: include: An acquisition unit is used to acquire several frames of infrared radiation images in a certain band of the detector and the current meteorological parameters of the detector; A division unit, used for dividing the target area and the background area in each frame of infrared radiation image by using a connected domain method; A first calculation unit, used to calculate the signal-to-noise ratio of each frame of infrared radiation image based on the grayscale values ​​of the target area and the background area and set a signal-to-noise ratio threshold; A screening unit, used to remove infrared radiation images whose signal-to-noise ratio is less than the signal-to-noise ratio threshold, to obtain a plurality of frames of screened infrared radiation images; A determination unit, configured to calculate the mean and standard deviation of the radiance of the selected infrared radiation images based on the instantaneous field of view of the detector and the calibration coefficient, and determine the stellar radiance in the current detection band based on the mean and standard deviation of the radiance; The second calculation unit is used to reversely calculate the stellar radiance in any detection band according to the current meteorological parameters of the detector, the stellar radiance in the current detection band and the star catalog database.

9. A computing device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method according to any one of claims 1 to 7.

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