Relative radiation correction method and device for wide medium-wave infrared remote sensing image

Abstract

The invention discloses a relative radiation correction method and device for a wide medium-wave infrared remote sensing image, and relates to the technical field of image correction, and the method comprises the steps: obtaining a to-be-processed infrared remote sensing image; determining a corresponding correction coefficient based on two adjacent detector units in each single linear array in the infrared remote sensing image; obtaining a residual error based on the output signals of the two detector units and the corresponding correction coefficients; a high-quality signal is obtained based on residual error judgment; circulating the process to obtain high-quality signals in all single linear arrays in the infrared remote sensing image as a single linear array screening signal set; screening signal sets based on all the single-chip linear arrays to form a high-quality signal set; obtaining a correction parameter based on the single-chip linear array screening signal set and the high-quality signal set; and correcting output signals of all the single linear arrays in the infrared remote sensing image based on the correction parameters to obtain a corrected infrared remote sensing image. The non-uniformity correction of the infrared remote sensing image is realized, and the surface feature radiation information is precisely restored.

Description

Technical Field

[0001] The present invention relates to the technical field of image correction, and more specifically, to a relative radiometric correction method and device for wide-field medium-wave infrared remote sensing images. Background Art

[0002] At present, spaceborne push-broom wide-field infrared cameras can realize all-weather sensing of surface information within a super-large field of view space range, and play a significant role in remote sensing applications such as ecological environment monitoring, agricultural asset assessment, and disaster warning. However, limited by the imaging mechanism of spaceborne infrared sensors, on the one hand, infrared images have the characteristic of low intrinsic contrast, and it is difficult to accurately distinguish ground object information from infrared images without radiometric correction processing; on the other hand, there are inconsistencies in the responses of each photosensitive component of the infrared detector, and even in a uniform background, there will be obvious textures in its output image. Moreover, for the imaging optical system of a wide-field medium-wave infrared detector, the background radiation intensity is larger and the optical path is more complex than that of the imaging optical system of traditional infrared detectors, and the resulting instability significantly enhances the degradation effect on infrared images.

[0003] The relative radiometric correction technology of push-broom infrared line array cameras has been greatly improved. Among them, the most widely used is the radiometric calibration method based on on-board blackbodies. The prerequisite for implementing this method is the existence of a full-aperture and full-optical-path blackbody calibration device in the imaging system. However, for large-field high-resolution infrared cameras, it is difficult and costly to design a full-aperture and full-optical-path calibration blackbody in the imaging system, and the feasibility is not high. Therefore, when performing ground radiometric correction processing, this method cannot be used, and it is necessary to rely on the single-track statistical method to correct the non-uniformity of the image. For traditional single-track statistical methods, such as the standard moment matching algorithm, when the ground object information obtained by each detector unit varies greatly, while suppressing the radiation difference between pixels, it changes the true radiation characteristics of the ground object, and its correction effect is unstable and has a greater impact on subsequent applications.

[0004] Therefore, how to achieve non-uniformity correction of infrared remote sensing images and then accurately restore the radiation information of ground objects is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a relative radiometric correction method and device for wide-field medium-wave infrared remote sensing images, which realizes non-uniformity correction of infrared remote sensing images and then accurately restores the radiation information of ground objects.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A relative radiometric correction method for wide-field medium-wave infrared remote sensing images, comprising:

[0008] Obtaining an infrared remote sensing image to be processed;

[0009] Determine the corresponding correction coefficient based on two adjacent detector units in each single linear array in the infrared remote sensing image;

[0010] Obtain the residual based on the output signals of the two detector units and the corresponding correction coefficient;

[0011] Judge to obtain the high-quality signal based on the residual;

[0012] Loop the above process to obtain the high-quality signals in all single linear arrays in the infrared remote sensing image as the single linear array screening signal set;

[0013] Compose the high-quality signal set based on all the single linear array screening signal sets;

[0014] Obtain the correction parameter based on the single linear array screening signal set and the high-quality signal set;

[0015] Correct the output signals of all the single linear arrays in the infrared remote sensing image based on the correction parameter to obtain the corrected infrared remote sensing image.

[0016] Preferably, the method for determining the correction coefficient is:

[0017] Determine the correction coefficient corresponding to the detector unit by using a blackbody radiation source based on the laboratory calibration strategy of the mid-wave infrared camera;

[0018] The correction coefficient includes: a gain coefficient and an intercept factor.

[0019] Preferably, the method for obtaining the residual is:

[0020] Obtain the residual detH based on the output signals of the current two adjacent detector units and the corresponding correction coefficient:

[0021] detH = (k i ×Y i -k j ×Y j )-(b j -b i );

[0022] Wherein, k i represents the gain coefficient of the i-th detector unit, k j represents the gain coefficient of the j-th detector unit, the i-th detector unit is adjacent to the j-th detector unit, Y i represents the output signal of the i-th detector unit, Y j represents the output signal of the j-th detector unit, b i represents the intercept factor of the i-th detector unit, b jRepresents the intercept factor of the j-th detector unit.

[0023] Preferably, high-quality signals are obtained based on the residual judgment, specifically including:

[0024] Judge whether the absolute value of the residual is less than the threshold;

[0025] If so, take the output signals of two adjacent detector units as the high-quality signals;

[0026] Otherwise, continue to judge the residuals of other adjacent pairs of detector units in sequence until all detector units in the current single-line array are judged, and all the high-quality signals in the current single-line array are obtained.

[0027] Preferably, the method for obtaining the correction parameter is:

[0028] Based on all the high-quality signals in the signal set screened by the single-line array, obtain the single-line array mean and the single-line array variance together as the first parameter;

[0029] Based on all the high-quality signals in the high-quality signal set, obtain the overall mean and the overall variance together as the second parameter;

[0030] Based on the first parameter and the second parameter, jointly form the correction parameter.

[0031] Preferably, the single-line array mean u i and the single-line array variance δ i are respectively:

[0032]

[0033] where Y i,j represents the high-quality signals in the signal set screened by the single-line array, i represents the serial number of the single-line array, j represents the serial number of the detector unit, and M represents the number of imaging output rows.

[0034] Preferably, the overall mean u r and the overall variance δ r are respectively:

[0035]

[0036]

[0037] where N represents the number of single-line arrays.

[0038] Preferably, the method for obtaining the corrected infrared remote sensing image is:

[0039] Based on the correction parameters, correct the output signals in all the single-line arrays in the infrared remote sensing image according to the corresponding single-line arrays to obtain the corrected output code values of the single-line arrays;

[0040] Based on all the output code values of the single-line arrays, obtain the corrected infrared remote sensing image.

[0041] Preferably, the output code value of the single-line array is specifically:

[0042]

[0043] where Y i,j ’ represents the corrected output code value of the single-line array.

[0044] A relative radiometric correction device for a wide-field mid-wave infrared remote sensing image, comprising: an image acquisition module, a correction coefficient acquisition module, a high-quality signal determination module, a signal set acquisition module, a correction parameter acquisition module, and an image correction module;

[0045] The image acquisition module is used to acquire the infrared remote sensing image to be processed;

[0046] The correction coefficient acquisition module is used to determine the corresponding correction coefficient based on two adjacent detector units in each single-line array in the infrared remote sensing image;

[0047] The high-quality signal determination module is used to obtain the residual based on the output signals of the two detector units and the corresponding correction coefficient; judge the high-quality signal based on the residual;

[0048] The signal set acquisition module is used to loop the above process to obtain the high-quality signals in all the single-line arrays in the infrared remote sensing image as the single-line array screening signal set; form the high-quality signal set based on all the single-line array screening signal sets;

[0049] The correction parameter acquisition module is used to obtain the correction parameter based on the single-line array screening signal set and the high-quality signal set;

[0050] The image correction module is used to correct the output signals of all the single-line arrays in the infrared remote sensing image based on the correction parameter to obtain the corrected infrared remote sensing image.

[0051] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses a relative radiometric correction method and device for wide-field mid-wave infrared remote sensing images. Based on the imaging mechanism of mid-wave infrared detectors, the present invention uses the radiation characteristics of the camera system as the sample control basis in the scene method. After screening out reasonable high-quality samples, the non-uniformity correction coefficients of each detector unit are calculated. During the calculation process, the device maintains the stability of the detector unit gain coefficient, is less affected by the statistical differences brought by the samples in the imaging scene, and has strong algorithm robustness. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0053] Figure 1 It is a flowchart of a relative radiometric correction method for wide-field mid-wave infrared remote sensing images provided by the present invention.

[0054] Figure 2 It is a schematic diagram of the optoelectronic response curve obtained by a camera system with 6 detectors provided by the present invention for a uniform blackbody at different temperatures.

[0055] Figure 3 It is the original image provided by the present invention during the day.

[0056] Figure 4 It is the original image provided by the present invention at night.

[0057] Figure 5 It is the daytime image corrected by the moment matching method provided by the present invention.

[0058] Figure 6 It is the daytime image corrected by the method of the present invention provided by the present invention.

[0059] Figure 7 It is the nighttime image corrected by the moment matching method provided by the present invention.

[0060] Figure 8 It is the nighttime image corrected by the method of the present invention provided by the present invention.

[0061] Figure 9 It is a schematic diagram of the structure of a relative radiometric correction device for wide-field mid-wave infrared remote sensing images provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0062] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0063] Embodiment 1

[0064] As Figure 1 shown, an embodiment of the present invention discloses a relative radiometric correction method for wide-field mid-wave infrared remote sensing images, including:

[0065] Obtain the infrared remote sensing image to be processed;

[0066] Based on two adjacent detector units in each single-line array in the infrared remote sensing image, determine the corresponding correction coefficient;

[0067] Based on the output signals of the two detector units and the corresponding correction coefficient, obtain the residual;

[0068] Based on the residual, judge to obtain a high-quality signal;

[0069] Loop the above process to obtain the high-quality signals in all single-line arrays in the infrared remote sensing image as the single-line array screening signal set;

[0070] Based on all the single-line array screening signal sets, form a high-quality signal set;

[0071] Based on the single-line array screening signal set and the high-quality signal set, obtain the correction parameters;

[0072] Based on the correction parameters, correct the output signals of all single-line arrays in the infrared remote sensing image to obtain a corrected infrared remote sensing image.

[0073] Embodiment 2

[0074] Ideally, assuming that the response relationship between each detector unit and the input energy is linear, the output response of the i-th detector unit among the n detector units in the focal plane array at time t can be expressed as:

[0075] x i (t) = k i (t) × y i (t) + b i (t);

[0076] In the formula, y i (t) is the radiation energy received by the i-th detector unit at the t-th moment, x i (t) is the output code value of the detector unit i, k i(t) is the response sensitivity corresponding to detector unit i, that is, the gain coefficient (this coefficient is independent of the incident parameters) and b i (t) is the pixel response offset, that is, the intercept factor (this coefficient is related to the dark level of the detector unit).

[0077] If the responses of each detector unit are consistent, then the k i (t) of each detector unit is the same, and b i (t) is 0. However, in fact, under the condition of the same input energy, the k i (t) and b i (t) of each detector unit are not all the same, that is to say, the infrared array image has non-uniformity. In order to correct the outputs of pixels with inconsistent responses to be consistent, the above formula is transformed into the non-uniformity correction formula for detector unit i, that is:

[0078] y i (t) = G i (t) × x i (t) + O i (t);

[0079] G i (t) = 1 / k i (t);

[0080] O i (t) = -b i (t) / k i (t);

[0081] Among them, G i (t) is the gain correction factor of the i-th detector unit, and O i (t) is the intercept correction factor of the i-th detector unit.

[0082] For an infrared camera, the imaging environment needs to be cooled to a fixed temperature to perform imaging work, and a slight change in the background temperature will change the intercept correction factor of each pixel. Therefore, the imaging signals of each pixel of a spaceborne infrared camera cannot be accumulated and do not have statistical characteristics, and independent non-uniformity correction needs to be performed on each acquired track of images.

[0083] A spaceborne infrared camera with a small aperture has a variable-temperature uniform blackbody in the entire optical path. When imaging, the code value signal of the variable-temperature uniform blackbody can be obtained. According to the above formula, the non-uniformity correction coefficient of the corresponding pixel can be calculated. This calibration-based method is widely used in the non-uniformity correction of spaceborne infrared camera images. However, a push-broom camera with a wide field of view and high resolution does not have a variable-temperature blackbody in the entire optical path and cannot use the calibration method. Therefore, it is necessary to rely on the single-scene image scene correction method to correct the non-uniformity of the image.

[0084] Based on this, an embodiment of the present invention discloses a relative radiometric correction method for wide - field mid - wave infrared remote sensing images, including:

[0085] Obtain the infrared remote sensing image to be processed.

[0086] Preferably, the infrared remote sensing image is composed of sub - images stitched together by multiple single - chip linear arrays. Each single - chip linear array consists of multiple detector units, and the output signals of all detector units in each single - chip linear array jointly form the corresponding sub - image.

[0087] Preferably, the infrared remote sensing image to be processed in this embodiment is an arbitrarily imaged wide - field - of - view and high - resolution single - scene image.

[0088] Determine the corresponding correction coefficients based on two adjacent detector units in each single - chip linear array of the infrared remote sensing image.

[0089] Preferably, the method for determining the correction coefficients is:

[0090] Based on the laboratory calibration strategy of the mid - wave infrared camera, use a blackbody radiation source to determine the correction coefficients corresponding to the detector units;

[0091] The correction coefficients include: gain coefficients and intercept factors.

[0092] Obtain the residuals based on the output signals of two detector units and the corresponding correction coefficients.

[0093] Preferably, based on all detector units in the single - chip linear array, sequentially obtain the output signals of two adjacent detector units and the corresponding correction coefficients to calculate the residuals. For example, if the single - chip linear array includes 7 detector units {a1, a2, a3, a4, a5, a6, a7}, then first calculate the residual of adjacent detector units a1 and a2, then calculate the residual of a2 and a3, and so on.

[0094] Preferably, the method for obtaining the residuals is:

[0095] Obtain the residual detH based on the output signals of the current two adjacent detector units and the corresponding correction coefficients:

[0096] detH=(k i ×Y i -k j ×Y j )-(b j -b i );

[0097] Wherein, k i represents the gain coefficient of the i - th detector unit, k jrepresents the gain coefficient of the j-th detector unit, where the i-th detector unit is adjacent to the j-th detector unit, Y i represents the output signal of the i-th detector unit, Y j represents the output signal of the j-th detector unit, b i represents the intercept factor of the i-th detector unit, b j represents the intercept factor of the j-th detector unit.

[0098] Preferably, the output signal Y of the i-th detector unit i is:

[0099]

[0100] where, DN i,M represents the DN value output by the i-th detector unit in the M-th row.

[0101] Preferably, the output signal Y of the j-th detector unit j is:

[0102]

[0103] where, DN j,M represents the DN value output by the j-th detector unit in the M-th row.

[0104] Preferably, in the ideal case where the camera imaging state is exactly the same as the laboratory calibration test state:

[0105] Then: At this time, let:

[0106]

[0107] High-quality signals are obtained based on residual judgment.

[0108] Preferably, obtaining high-quality signals based on residual judgment specifically includes:

[0109] Judging whether the absolute value of the residual is less than the threshold;

[0110] If so, the output signals of two adjacent detector units are used as high-quality signals;

[0111] Otherwise, continue to judge the residuals of other adjacent pairs of detector units in sequence until all detector units in the current single-line array are judged, and all high-quality signals in the current single-line array are obtained.

[0112] Preferably, for example, a single linear array includes 7 detector units {a1, a2, a3, a4, a5, a6, a7}. First, calculate the residual based on adjacent detector units a1 and a2 and make a judgment. If the residual is less than the threshold, the output signals of detector units a1 and a2 are both regarded as high-quality signals, and then continue to calculate the residual based on adjacent detector units a3 and a4 and make a judgment, and so on; if the residual of detector units a1 and a2 is greater than or equal to the threshold, it does not meet the screening requirements, and continue to calculate the residual based on adjacent detector units a2 and a3 and make a judgment, and so on, and loop the above judgment process until all detector units in the current single linear array are judged to obtain all high-quality signals in the current single linear array.

[0113] Preferably, this algorithm uses the radiation characteristics of the camera system as the basis for sample control in the scene method. After screening out high-quality samples, calculate the correction parameters for the non-uniformity of each detector unit. During the calculation process of this algorithm, the gain coefficient k i of detector unit i is kept stable, less affected by sample differences in the imaging scene, and the algorithm has strong robustness.

[0114] Loop the above process to obtain all high-quality signals in all single linear arrays in the infrared remote sensing image as the single linear array screening signal set.

[0115] Preferably, based on the high-quality signals judged and screened in each single linear array in the infrared remote sensing image as the corresponding single linear array screening signal set.

[0116] Based on all single linear array screening signal sets, a high-quality signal set is formed.

[0117] Preferably, the high-quality signals in all single linear array screening signal sets jointly form a high-quality signal set.

[0118] Based on the single linear array screening signal set and the high-quality signal set, correction parameters are obtained.

[0119] Preferably, the method for obtaining correction parameters is:

[0120] Based on all high-quality signals in the single linear array screening signal set, the single linear array mean value and the single linear array variance are jointly used as the first parameter;

[0121] Based on all high-quality signals in the high-quality signal set, the overall mean value and the overall variance are jointly used as the second parameter;

[0122] Based on the first parameter and the second parameter, correction parameters are jointly formed.

[0123] Preferably, the single linear array mean value u i and the single linear array variance δ i are respectively:

[0124]

[0125] Among them, Y i,j represents the high-quality signals in the single-line array screening signals. i represents the serial number of the single-line array, j represents the serial number of the detector unit, and M represents the number of imaging output rows.

[0126] Preferably, the overall mean u r and the overall variance δ r are respectively:

[0127]

[0128] Among them, N represents the number of single-line arrays.

[0129] Based on the correction parameters, the output signals of all single-line arrays in the infrared remote sensing image are corrected to obtain a corrected infrared remote sensing image.

[0130] Preferably, the method for obtaining the corrected infrared remote sensing image is:

[0131] Based on the correction parameters, the output signals in all single-line arrays in the infrared remote sensing image are corrected according to the corresponding single-line arrays to obtain the corrected output code values of the single-line arrays;

[0132] Based on all the output code values of the single-line arrays, a corrected infrared remote sensing image is obtained.

[0133] Preferably, the output code value of the single-line array is specifically:

[0134]

[0135] Among them, Y i,j ’ represents the corrected output code value of the single-line array.

[0136] Embodiment 3

[0137] Experimentally verify the superiority of the method of the present invention:

[0138] Use the mid-wave infrared camera outdoor imaging data as the data source. The main parameters of the camera are shown in Table 1:

[0139] Table 1 Camera parameter list

[0140]

[0141] The photoelectric response curves obtained by the camera system with 6 detectors for uniform blackbodies at different temperatures are as Figure 2 shown. From Figure 2It can be seen that the photoelectric responses of the six detectors in the camera system are basically linear within the working range. According to this response curve, the correction coefficient (k i ,b i ) of each detector unit i of each single linear array can be calculated.

[0142] As an important target detection band, the mid-wave infrared band can image all day long. The temperature radiation information of the target is obtained at night, and during the day, the temperature radiation information of the target, the reflection and scattering information of the target, and the scattering information of the atmosphere are obtained. One image each for day and night is selected for algorithm analysis.

[0143] As Figures 3 - 4 shown, they are the original images for day and night respectively. There are targets such as buildings, sky background, and cirrus clouds in the images. The vertical direction of the image is the arrangement direction of the detector pixels, and the horizontal direction is the push-broom direction. It can be seen that the clouds in the mid-wave infrared image during the day have richer layers and higher brightness, and the sky background is relatively clean at night. The traditional moment matching correction method and the correction method of the present invention are respectively used to correct the image non-uniformity. The correction results are as Figures 5 - 8 shown. The non-uniformity of the image output by the original signal is very strong. Without processing, it is very difficult to distinguish the target information. At the same time, the response of the detector unit of the single-chip 1024-element has the characteristic that the center is strong and the strength weakens towards both sides. After non-uniformity correction, the above effects of the single-chip detector are basically eliminated. From the correction results, after correction by the traditional moment matching method, the building has the characteristic of uneven gray-scale distribution. Because the calculation of the non-uniformity correction coefficient of each detector unit by this method is easily interfered by the detected sample signal, when too bright or too dark targets are introduced into the sample, the calculation result has a large deviation, which in turn affects the correction result. After correction by the method of the present invention, the target is clearer and the gray-scale distribution is uniform, and the non-uniform stripes in the image are eliminated.

[0144] Two measurement criteria, the inverse coefficient of deviation ICV and the non-uniformity MUC, are used to evaluate the correction results.

[0145] Measurement criterion 1: Inverse coefficient of deviation

[0146] The inverse coefficient of deviation is used to evaluate the flatness of a specified area in the image. The larger the value, the better the flatness. Its expression is:

[0147]

[0148] In the formula, R m refers to the mean value of the specified area of the corrected image, and R d refers to the mean square deviation of the corresponding area of the corrected image.

[0149] Measurement criterion 2:

[0150] The national standard is used to define the MUC to evaluate the non-uniformity correction result of the image. The smaller the MUC calculation result is, the higher the correction accuracy is.

[0151] Its expression is:

[0152]

[0153] Among them, y i,j is the output code value of the detector unit i in the j-th frame, is the mean value of all pixels in the image area of size M×N.

[0154] Using the above measurement criteria, an area with a size of 2000×1900 pixels of a clean sky background at night is selected as the evaluation sample, and two evaluation indexes of the sample are calculated respectively, as shown in Table 2:

[0155] Table 2 Calculation results of different evaluation indexes

[0156]

[0157] Based on the analysis of the experimental results, the following conclusions are obtained:

[0158] (1) The ICV index of the traditional moment matching algorithm is 3.27 times that of the original image, and the ICV index of the correction result of the correction method of the present invention is 10.14 times that of the original image, which is 6.86 times higher than that of the traditional moment matching algorithm.

[0159] (2) For the MUC index, the calculation result of the traditional correction algorithm is 13.5%, and the calculation result of the correction method of the present invention is 4.4%, which is 9.13% lower than that of the traditional algorithm.

[0160] The correction method of the present invention reduces the dependence on statistical samples compared with the traditional correction algorithm due to the addition of the radiation constraint of the camera itself, and the robustness of the algorithm is stronger, which is conducive to engineering implementation. This method has been successfully applied to the on-orbit image preprocessing of spaceborne cameras. Compared with ground images, on-orbit images have better hierarchy and richer gray distribution information. The correction method of the present invention breaks through the design limitations of high-resolution large-field-of-view infrared cameras.

[0161] The correction method of the present invention proposes a real-time non-uniformity correction algorithm for a single-frame scene image based on the radiation characteristics constraint of the camera itself in view of the characteristics of a large-field-of-view push-broom infrared camera, breaks through the design limitations of large-field-of-view high-resolution infrared cameras, and greatly improves the non-uniformity correction accuracy of the corrected image. At the same time, for a single-frame image of 30000 elements * 30000 rows, the correction time of this algorithm is only about 1 minute.

[0162] Example 4

[0163] As Figure 9As shown in the figure, a relative radiometric correction device for wide - swath mid - wave infrared remote sensing images includes: an image acquisition module, a correction coefficient acquisition module, a high - quality signal determination module, a signal set acquisition module, a correction parameter acquisition module, and an image correction module;

[0164] The image acquisition module is used to acquire the infrared remote sensing image to be processed;

[0165] The correction coefficient acquisition module is used to determine the corresponding correction coefficient based on two adjacent detector units in each single - line array in the infrared remote sensing image;

[0166] The high - quality signal determination module is used to obtain the residual based on the output signals of two detector units and the corresponding correction coefficient; and judge the high - quality signal based on the residual;

[0167] The signal set acquisition module is used to loop the above process to obtain the high - quality signals in all single - line arrays in the infrared remote sensing image as the single - line array screening signal set; and form the high - quality signal set based on all single - line array screening signal sets;

[0168] The correction parameter acquisition module is used to obtain the correction parameter based on the single - line array screening signal set and the high - quality signal set;

[0169] The image correction module is used to correct the output signals of all single - line arrays in the infrared remote sensing image based on the correction parameter to obtain the corrected infrared remote sensing image.

[0170] Preferably, in this embodiment, the functional implementation processes of each functional module correspond one by one to the above - mentioned method content, and will not be elaborated here one by one.

[0171] Embodiment 5

[0172] Based on the same inventive concept, the present invention also provides a computer device, including a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus;

[0173] The memory is used to store a computer program;

[0174] When the processor is used to execute the program stored on the memory, it can implement a relative radiometric correction method for wide - swath mid - wave infrared remote sensing images as described in Embodiment 1 or 2.

[0175] The electronic device may include: a processor, a communications interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. The processor may call the logic instructions in the memory to execute the relative radiometric correction method for a wide-field mid-wave infrared remote sensing image in Embodiment 1 or 2.

[0176] In addition, when the logic instructions in the above-mentioned memory are implemented in the form of software functional units and sold or used as independent products, they may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, may be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0177] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses a relative radiometric correction method and device for a wide-field mid-wave infrared remote sensing image. The present invention is based on the imaging mechanism of a mid-wave infrared detector and uses the radiation characteristics of the camera system as the sample control basis in the scene method. After screening out reasonable high-quality samples, the non-uniformity correction coefficients of each detector unit are calculated. During the calculation process, the device maintains the stability of the gain coefficients of the detector units and is less affected by the statistical differences brought by the samples in the imaging scene, and the algorithm has strong robustness.

[0178] In this specification, the various embodiments are described in a progressive manner. The focus of each embodiment is on the differences from other embodiments. For the same or similar parts among the various embodiments, reference may be made to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference may be made to the description in the method part.

[0179] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images, characterized in that, Including: Obtain the infrared remote sensing image to be processed; Determine the corresponding correction coefficient based on two adjacent detector units in each single linear array in the infrared remote sensing image; Obtain the residual based on the output signals of the two detector units and the corresponding correction coefficient; Judge to obtain the high-quality signal based on the residual; Loop the above process to obtain the high-quality signals in all single linear arrays in the infrared remote sensing image as the single linear array screening signal set; Form a high-quality signal set based on all the single linear array screening signal sets; Obtain the correction parameter based on the single linear array screening signal set and the high-quality signal set; Correct the output signals of all the single linear arrays in the infrared remote sensing image based on the correction parameter to obtain the corrected infrared remote sensing image.

2. The relative radiometric correction method for a wide - swath mid - wave infrared remote sensing image according to claim 1, characterized in that, The method for determining the correction coefficient is: Based on the laboratory calibration strategy of the mid-wave infrared camera, use the blackbody radiation source to determine the correction coefficient corresponding to the detector unit; The correction coefficient includes: gain coefficient and intercept factor.

3. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 1, characterized in that, The method for obtaining the residual is: Obtain the residual detH based on the output signals of the current two adjacent detector units and the corresponding correction coefficient; detH=(k i ×Y i -k j ×Y j )-(b j -b i ); Among them, k i represents the gain coefficient of the i-th detector unit, and k j represents the gain coefficient of the j-th detector unit. The i-th detector unit is adjacent to the j-th detector unit. Y i represents the output signal of the i-th detector unit, and Y j represents the output signal of the j-th detector unit. b i represents the intercept factor of the i-th detector unit, and b j represents the intercept factor of the j-th detector unit.

4. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 1, characterized in that Judging to obtain the high-quality signal based on the residual specifically includes: Judge whether the absolute value of the residual is less than the threshold; If so, use the output signals of the two adjacent detector units as the high-quality signal; Otherwise, continue to judge the residuals of other adjacent two detector units in sequence until all the detector units in the current single linear array are judged to obtain all the high-quality signals in the current single linear array.

5. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 1, characterized in that, The method for obtaining the correction parameter is: Obtain the single linear array mean and the single linear array variance together as the first parameter based on all the high-quality signals in the single linear array screening signal set; Obtain the overall mean and the overall variance together as the second parameter based on all the high-quality signals in the high-quality signal set; Form the correction parameter based on the first parameter and the second parameter together.

6. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 5, characterized in that, The mean value u of the single-line array i and the variance δ of the single-line array i are respectively Among them, Y i,j represents the high-quality signals in the single-line array screening signals, i represents the serial number of the single-line array, j represents the serial number of the detector unit, and M represents the number of imaging output rows.

7. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 6, characterized in that, The overall mean μ r and the overall variance δ r are respectively: Wherein, N represents the number of single linear arrays.

8. A relative radiometric correction method for wide - swath mid - wave infrared remote sensing images according to claim 7, characterized in that, The method for obtaining the corrected infrared remote sensing image is: Correct the output signals in all the single linear arrays in the infrared remote sensing image according to the corresponding single linear array based on the correction parameter to obtain the corrected single linear array output code value; Obtain the corrected infrared remote sensing image based on all the single linear array output code values.

9. A relative radiometric correction method for wide-swath mid-wave infrared remote sensing images according to claim 8, characterized in that, The single linear array output code value specifically is: Among them, Y i,j ’ represents the corrected output code value of the single-line array.

10. A relative radiometric correction device for wide - swath mid - wave infrared remote sensing images, which is applied to a relative radiometric correction method for wide - swath mid - wave infrared remote sensing images as described in any one of claims 1 - 9, and is characterized in that Including: An image acquisition module, a correction coefficient acquisition module, a high-quality signal determination module, a signal set acquisition module, a correction parameter acquisition module, and an image correction module; The image acquisition module is used to obtain the infrared remote sensing image to be processed; The correction coefficient acquisition module is used to determine the corresponding correction coefficient based on two adjacent detector units in each single linear array in the infrared remote sensing image; The high-quality signal determination module is used to obtain the residual based on the output signals of the two detector units and the corresponding correction coefficient; judge to obtain the high-quality signal based on the residual; The signal set acquisition module is used to loop the above process to obtain the high-quality signals in all single-line arrays in the infrared remote sensing image as the single-line array screening signal set; and form a high-quality signal set based on all the single-line array screening signal sets; The correction parameter acquisition module is used to obtain correction parameters based on the single-line array screening signal set and the high-quality signal set; The image correction module is used to correct the output signals of all the single-line arrays in the infrared remote sensing image based on the correction parameters to obtain a corrected infrared remote sensing image.

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