Non-uniformity correction method based on derivative domain response rate correction

Through the derivative domain response rate correction method, the problem of poor non-uniformity correction effect caused by the nonlinear response curve in infrared imaging by the two-point correction algorithm is solved, and more accurate non-linear response curve and infrared image correction are achieved, which improves measurement Temperature accuracy.

CN119104160AActive Publication Date: 2024-12-10WUHAN GUIDE SENSMART TECH CO LTD

Patent Information

Application Number
CN202411461049.7
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-10-18
Publication Date
2024-12-10
Estimated Expiration
2044-10-18

AI Technical Summary

Technical Problem

The existing two-point correction algorithm has poor non-linear response curves during infrared imaging, resulting in poor non-uniformity correction effect, which cannot accurately describe the response rate of each temperature point, affecting the temperature measurement accuracy.

Method used

Using the response rate correction method based on the derivative domain, the response curve function of each cell is obtained by setting the bold body of different temperatures, and the response curve function of each cell is obtained, and the response rate correction parameter set of each cell is obtained, and then the response rate correction parameter set is performed. Inhomogeneity correction, obtain more accurate nonlinear response curves and corrected infrared images.

Benefits of technology

Improves the accuracy of infrared images, reduces noise, and enhances the accuracy of temperature measurement results.

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Abstract

The invention relates to a heterogeneity correction method based on derivative domain response rate correction. The heterogeneity correction method comprises the following steps: setting black bodies with different temperatures; obtaining an image of each black body through an infrared imaging device, and collecting the response of an infrared detector to the current black body temperature when the image of each black body is obtained; based on the response to the current blackbody temperature, fitting to obtain a response curve function of each pixel to different blackbody temperatures, and correspondingly obtaining the response rate of each pixel at any temperature; correcting the response rate of each pixel; and performing non-uniformity correction on the infrared image, and outputting the corrected infrared image. According to the method, the response rate of each pixel can be accurately described in a derivative domain based on the theoretical basis that the response of the pixel to different radiation quantities is a nonlinear relationship, and the response rate of each pixel is further subjected to non-uniformity correction, so that a more accurate nonlinear response curve and a corrected infrared image are obtained, and the accuracy of the infrared image is improved. Therefore, the noise of the infrared image is reduced, and the temperature measurement result precision is improved.
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Description

Technical Field

[0001] The invention relates to the field of infrared imaging technology, and in particular to a non-uniformity correction method based on derivative domain response rate correction. Background Art

[0002] In the infrared imaging process, since the response characteristics of each pixel on the infrared detector cannot be guaranteed to be completely consistent, the same amount of thermal radiation will produce different grayscale values ​​on different pixels of the image. This characteristic of the infrared detector is called non-uniformity. This non-uniformity needs to be corrected by an algorithm to ensure the accuracy of the infrared temperature measurement results.

[0003] Common non-uniformity correction algorithms include single-point correction, two-point correction, etc. The single-point correction algorithm assumes that the response difference of the pixel is a fixed value and does not change with the target temperature. Therefore, correction can be achieved by subtracting a fixed value from the pixel value of each pixel in the image.

[0004] The two-point correction algorithm is the more commonly used non-uniformity correction method. It assumes that the response of the pixel is linearly related to the target temperature, and there are differences in response rate and bias. It needs to be implemented through a gain matrix that controls the slope and a background matrix that controls the bias.

[0005] However, the two-point correction algorithm has the following problems when performing non-uniformity correction: 1) The theoretical basis of the two-point correction algorithm assumes that the response curve of the pixel is linear, but this linear relationship does not match the actual response curve, which can easily lead to poor non-uniformity correction effects in some scenes; 2) When performing response rate correction, the two-point correction algorithm uses the ratio of the grayscale value difference to the target temperature difference to evaluate the response rate. This method obtains the average response rate in a certain temperature range and cannot accurately describe the response rate of the response curve at each temperature point. Summary of the invention

[0006] The purpose of the present invention is to provide a non-uniformity correction method based on derivative domain response rate correction, which is based on the theoretical basis that the response of the pixel to different radiation amounts is a nonlinear relationship, accurately describes the response rate of each pixel in the derivative domain, and further performs non-uniformity correction on the response rate of each pixel to obtain a more accurate nonlinear response curve and a corrected infrared image, thereby reducing the noise of the infrared image and improving the accuracy of the temperature measurement results.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A non-uniformity correction method based on derivative domain responsivity correction is provided, which comprises the following steps:

[0009] Set up N black bodies with different temperatures;

[0010] Acquire an image of each black body through an infrared imaging device, and collect the response of the infrared detector of the infrared imaging device to the current black body temperature when acquiring each black body image;

[0011] Based on the response of the infrared detector to the current black body temperature, the response curve function f(T; P) of each pixel to different black body temperatures is fitted, and the response curve function f(T; P) of each pixel is derived to obtain the response rate f′(T; P) of each pixel at any temperature.

[0012] Correct the response rate f′(T; P) of each pixel so that the response rate f′(T; P) of each pixel is the same as the preset response rate, and record the response rate correction parameter set Q of each pixel during the correction process;

[0013] Perform non-uniformity correction on the infrared image and output the corrected infrared image.

[0014] Preferably, the response curve function f(T; P) is a quadratic polynomial curve obtained based on fitting, and its expression is shown in formula (1):

[0015] f (T;P) =p1×T 2 +p2×T+p3 (1)

[0016] Among them, T is the black body temperature; P is the response curve parameter set of the current pixel to different black body temperatures; p1, p2, and p3 are all parameters in the response curve parameter set.

[0017] Preferably, the response rate f′(T; P) of each pixel is corrected so that the response rate f′(T; P) of each pixel is the same as the preset response rate, including the following steps:

[0018] Get the center point response rate f′ of the center point of the image c(T;P) ;

[0019] Construct the center point response rate f′ c(T;P) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate f′ c(T;P) same.

[0020] Preferably, the response rate f′(T; P) of each pixel is corrected so that the response rate f′(T; P) of each pixel is the same as the preset response rate, including the following steps:

[0021] The full-image response mean value A of all pixels when the infrared imaging device acquires each black body image is calculated;

[0022] The mean response curve f of the whole image is obtained by fitting the mean response A of all the whole images. m(T;A) , where T is the blackbody temperature;

[0023] The mean response curve f for the whole graph m(T;A) Derivative, get the average response rate f' of the whole picture m(T;A) ;

[0024] Construct the average response rate f' of the whole graph m(T;A) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate of the whole picture f' m(T;A) same.

[0025] Preferably, performing non-uniformity correction on the infrared image and outputting the corrected infrared image specifically comprises the following steps:

[0026] Acquire an infrared image of the current target through an infrared imaging device, and obtain the current response rate of each pixel;

[0027] The target temperature T is calculated based on the current response rate of each pixel;

[0028] The current response rate of the current pixel is corrected according to the response rate correction parameter set Q of each pixel to obtain a nonlinear response curve after the non-uniformity of each pixel is corrected, and a corrected infrared image is output.

[0029] Preferably, the current response rate of each pixel is corrected according to the response rate correction parameter set Q of each pixel to obtain a nonlinear response curve after the non-uniformity of each pixel is corrected, including the following steps:

[0030] pass The response rate f′ to the current pixel x x(T;P) Correction is made, where f xc (T) is the nonlinear response curve of the current pixel x after non-uniformity correction, g x (*) is the response rate f′ of the current pixel x x(T;P) and the central point response rate f′ c(T;P) Or the average response rate of the whole graph f' m(T;A) The mapping relationship between them.

[0031] Preferably, performing non-uniformity correction on the infrared image and outputting the corrected infrared image specifically comprises the following steps:

[0032] Obtain an infrared image of the current target through an infrared imaging device, and obtain the true response of each pixel based on the infrared detector;

[0033] The target temperature T is calculated by the following formula:

[0034]

[0035] Where T is the target temperature obtained by inverse calculation; G is the actual response of the current pixel;

[0036] Substitute the inversely calculated target temperature T and the actual response G of the current pixel into the following formula to obtain the corrected response G1 of the current pixel:

[0037] G1=q1×G+q2×T+C

[0038] Set the shutter temperature T s , shutter response G s Substitute into the following formula to obtain the corrected shutter response G2 of the current pixel:

[0039] G2=q1×G s +q2×T s +C

[0040] Each pixel is bias-corrected by the following formula to obtain the non-uniformity correction response value G3:

[0041] G3=G1-G2=q1×G+q2×T+C-q1×G s +q2×T s + C = q1 × (GG s )+q2×(TT s );

[0042] The corrected infrared image is output according to the non-uniformity correction response value G3 of each pixel to complete the non-uniformity correction.

[0043] Preferably, after the temperatures of all black bodies are arranged in descending or ascending order, the temperature intervals between every two adjacent black body temperatures are the same.

[0044] Preferably, before acquiring the first black body image, the infrared imaging device needs to be placed in a constant temperature environment after being turned on until the temperature of the focal plane of the infrared detector becomes constant.

[0045] Preferably, when the infrared imaging device acquires an image of any black body, the black body fills the entire imaging field of view.

[0046] In summary, the present invention has the following beneficial effects compared with the prior art:

[0047] The present invention is based on the theoretical foundation that the response of pixels to different radiation amounts is a nonlinear relationship. It accurately describes the response rate of each pixel in the derivative domain and obtains a response rate correction parameter set for each pixel. The response rate of each pixel is further corrected for non-uniformity through integration and bias correction. At the same time, a more accurate nonlinear response curve and a corrected infrared image are obtained, thereby reducing the noise of the infrared image and improving the accuracy of the temperature measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a flowchart of the steps of the non-uniformity correction method of the present invention;

[0049] Figure 2 These are infrared images without non-uniformity correction, after being processed by the conventional two-point correction method, and after being processed by the correction method of the present invention. DETAILED DESCRIPTION

[0050] 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 only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of 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.

[0051] Example 1

[0052] In the prior art, the infrared temperature measurement process is completed based on infrared imaging equipment. The infrared imaging equipment includes an infrared detector, which can sense the infrared radiation of the target object and convert it into an electrical signal. The temperature distribution of the target object is simulated by further processing the electrical signal to obtain the temperature of the target object. In this process, non-uniformity correction is required to ensure the accuracy of the infrared temperature measurement results and reduce the infrared image noise.

[0053] On this basis, if Figure 1 As shown, this embodiment provides a non-uniformity correction method based on derivative domain response rate correction, which includes the following steps:

[0054] S1. Set N black bodies with different temperatures in the scene, where N is a positive integer greater than or equal to 5. At the same time, after the temperatures of all black bodies are arranged in descending or ascending order, the temperature interval between every two adjacent black body temperatures is the same. For example, in this embodiment, a black body corresponding to 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, and 50°C can be set, for a total of 11 black bodies;

[0055] S2, acquiring an image of each black body through an infrared imaging device, and collecting a response of the infrared detector of the infrared imaging device to the current black body temperature when acquiring each black body image;

[0056] Wherein, before acquiring the first black body image, the infrared imaging device needs to be placed in a constant temperature environment after being turned on until the temperature of the focal plane of the infrared detector is constant, wherein the constant temperature of the focal plane of the infrared detector means that the temperature of the focal plane of the infrared detector fluctuates within a predetermined temperature range within a predetermined time period; the response includes an electrical signal obtained by converting the infrared radiation signal of the black body, and the conversion process can be realized by a corresponding conversion unit;

[0057] At the same time, when the infrared imaging device acquires the image of any black body, the black body fills the entire imaging field of view to ensure that the response of each pixel is related to the black body;

[0058] S3. Based on the response of the infrared detector to the current black body temperature, the response curve function f(T; P) of each pixel to different black body temperatures is obtained by fitting. In this embodiment, the response curve function f(T; P) can be a quadratic polynomial curve obtained based on fitting, and its expression is shown in formula (1):

[0059] f(T;P)=p1=T 2 +p2×T+p3 (1)

[0060] Wherein, T is the black body temperature; P is the response curve parameter set of the current pixel to different black body temperatures; p1, p2, and p3 are all parameters in the response curve parameter set;

[0061] For example, in this embodiment, the expression of the response curve function f(T; P) of each pixel is the same, such as the quadratic polynomial function, and the horizontal coordinates are different black body temperatures, and the vertical coordinates are the responses of the same pixel to different black body temperatures. However, for different pixels, the parameters p1, p2, and p3 during fitting are different, so the response curve parameter set of the response curve function f(T; P) of each pixel is also different.

[0062] S4. Deriving the response curve function f(T; P) of each pixel to obtain the response rate f′(T; P) of each pixel at any temperature. For example, in this embodiment, if the response curve function f(T; P) is a quadratic polynomial curve, the response rate f′(T; P) is obtained by derivation as shown in formula (2):

[0063] f′ (T;P) =2×p1×T+p2 (2)

[0064] Wherein, the meanings of T, p1, and p2 are the same as those in the above formula (1) and will not be repeated here;

[0065] S5, correcting the response rate f′(T; P) of each pixel so that the response rate f′(T; P) of each pixel is the same as the preset response rate, and recording and storing the response rate correction parameter set Q of each pixel during the correction process;

[0066] In this embodiment, the preset response rate includes the response rate of the pixel corresponding to the center point of the image, that is, the center point response rate, or the average response rate of the whole image;

[0067] Specifically, when the preset response rate = the center point response rate, first obtain the center point response rate f′ of the center point of the image. c(T;P) , and then construct the central point response rate f′ c(T;P) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate f′ c(T;P) The same is done to complete the response rate correction of each pixel;

[0068] The above mapping process can be described by the following formula (3):

[0069]

[0070] The mapping relationship g can be any function, including but not limited to a linear function, a quadratic polynomial function, etc. Q is the pixel response rate correction parameter set of any point in the image, that is, any point in the image has a corresponding response rate f′ x(T;P) and a response rate correction parameter set Q, and the response rate correction parameter set Q of each pixel may be different, which may be determined according to the data fitting process, etc. in the process of actually constructing the mapping relationship g;

[0071] For example, if the mapping relationship g is a linear function, the response rate correction process of the above pixel can be described by formula (4):

[0072] f′ c(T;P) =q1×f′ x(T;P) +q2 (4)

[0073] Among them, q1 and q2 are parameters in the response rate correction parameter set Q;

[0074] If the response curve function f(T; P) is a quadratic linear function, the response rate correction process of the above pixel can be described by formulas (5)-(7):

[0075] 2×p c1 ×T+p c2 =q1×(2×p x1 ×T+p x2 )+q2 (5)

[0076]

[0077] q2=p c2 -q1×p x2 (7)

[0078] Among them, q1 and q2 are parameters in the response rate correction parameter set Q; p c1 、p c2 The response curve function f is the center point of the image. c (T; P) is a parameter in the response curve parameter set P; p x1 、p x2 The response curve function f is the response curve function of any point in the image. x Parameters in the response curve parameter set P of (T; P);

[0079] When the preset response rate = the average response rate of the whole image, firstly, the whole image response mean value A of all pixels when the infrared imaging device acquires each black body image is calculated, and the whole image response mean value A = the sum of all pixel responses in the current black body image / the total number of pixels in the current black body image; then, the whole image response mean curve f is obtained by fitting according to all the whole image response mean values ​​A m(T;A) , where T is the blackbody temperature, the horizontal axis is the different blackbody temperatures, and the vertical axis is the mean value A of all full-image responses; continue to calculate the full-image response mean curve f m(T;A) By taking the derivative, we can get the average response rate f' of the whole graph. m(T;A) ;

[0080] Furthermore, the average response rate f' of the whole graph is constructed m(T;A) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate of the whole picture f' m(T;A) The same is used to complete the pixel response rate correction;

[0081] The above mapping process can be described by the following formula (8):

[0082]

[0083] Among them, the mapping relationship g can also be any function, including but not limited to a linear function, a quadratic polynomial function, etc.; Q is the pixel response rate correction parameter set of any point in the image, that is, any point in the image has a corresponding response rate f′ x(T;P) and a response rate correction parameter set Q, and the response rate correction parameter set Q of each pixel may be different, and the response rate correction parameter set Q may also be determined according to an actual data fitting process, etc.;

[0084] At the same time, when the mapping relationship g is a linear function and a quadratic linear function, the corresponding pixel response rate correction process is the same as the mapping relationship g (that is, the same as formula (4) and formula (5)-(7) respectively), and will not be repeated;

[0085] S6, performing non-uniformity correction on the infrared image and outputting the corrected infrared image, which specifically includes the following steps:

[0086] An infrared image of the current target (i.e., the target to be subjected to infrared temperature measurement) is obtained through an infrared imaging device, and the response rate of each pixel is obtained based on the infrared detector;

[0087] The target temperature T is calculated based on the current response rate of each pixel;

[0088] Correcting the response rate of the current pixel according to the response rate correction parameter set Q of each pixel to obtain a nonlinear response curve after the non-uniformity correction of each pixel, thereby completing the non-uniformity correction and outputting the corrected infrared image;

[0089] The response rate of each pixel is corrected according to the response rate correction parameter set Q of each pixel to obtain a nonlinear response curve after the non-uniformity of each pixel is corrected, including the following steps:

[0090] pass The response rate f′ to the current pixel x(T;P) Correction is made, where f xc (T) is the nonlinear response curve of the current pixel after non-uniformity correction.

[0091] Therefore, this embodiment is based on the theoretical foundation that the response of pixels to different radiation amounts (expressed as grayscale values ​​on the image) is a nonlinear relationship, accurately describes the response rate of each pixel in the derivative domain, and obtains the response rate correction parameter set Q of each pixel. The response rate of each pixel is further corrected for non-uniformity through integration, thereby obtaining a more accurate nonlinear response curve and a corrected infrared image.

[0092] like Figure 2 As shown, parts (a), (b), and (c) are infrared images without non-uniformity correction, after conventional two-point correction method processing, and after correction method processing in this embodiment, respectively. It can be seen that compared with the conventional two-point correction algorithm, the image noise obtained after correction by the method in this embodiment is significantly reduced, which helps to improve the temperature measurement accuracy.

[0093] Embodiment 2:

[0094] The difference between this embodiment and embodiment 1 is that if the center point response rate f′ of the center point of the image c(T;P)Or the average response rate of the whole graph f' m(T;A) The response rate f′ of any point in the image x(T;P) When the mapping relationship g between is a linear function, we have:

[0095]

[0096] Where C is an arbitrary constant value generated by the indefinite integral.

[0097] However, the constant value C mentioned above will result in an inability to obtain an accurate correction result, and the constant value C corresponding to each pixel may be different. Therefore, the constant value C mentioned above needs to be eliminated to obtain an accurate temperature measurement result. Furthermore, since there are differences in bias between each pixel, and infrared imaging devices are generally provided with a shutter, the response of the scene when the shutter is closed can be subtracted from the response of the shutter, thereby completing the bias correction to eliminate the constant value C mentioned above.

[0098] Specifically, when the response curve is a quadratic polynomial function and the mapping relationship is a linear function, step S6 specifically includes the following steps:

[0099] The infrared image of the current target (i.e., the target to be subjected to infrared temperature measurement) is obtained through the infrared imaging device, and the real response of each pixel is obtained based on the infrared detector;

[0100] The target temperature T is calculated by the following formula:

[0101]

[0102] Wherein, T is the target temperature obtained by inverse calculation; G is the real response of the current pixel, and the real response may be the gray value of the current pixel in the current infrared image;

[0103] Substitute the inversely calculated target temperature T and the actual response G of the current pixel into the following formula to obtain the corrected response G1 of the current pixel:

[0104] G1=q1×G+q2×T+C

[0105] Similarly, the shutter temperature T s , shutter response G s (which can be the gray value of the current pixel in the shutter infrared image) is substituted into the following formula to obtain the corrected shutter response G2 of the current pixel:

[0106] G2=q1×G s +q2×T s +C

[0107] Each pixel is bias-corrected by the following formula to obtain the non-uniformity correction response value G3:

[0108] G3=G1-G2=q1×G+q2×T+C-q1×G s +q2×T s + C = q1 × (GG s )+q2×(TT s );

[0109] The corrected infrared image is output according to the non-uniformity correction response value G3 of each pixel to complete the non-uniformity correction.

[0110] In summary, the present invention is based on the theoretical foundation that the response of pixels to different radiation amounts (expressed as grayscale values ​​on the image) is a nonlinear relationship. It accurately describes the response rate of each pixel in the derivative domain, and obtains the response rate correction parameter set Q of each pixel. The response rate of each pixel is further corrected for non-uniformity through integration and bias correction, and a more accurate nonlinear response curve and a corrected infrared image are obtained at the same time, thereby reducing the noise of the infrared image and improving the accuracy of the temperature measurement results.

[0111] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A non-uniformity correction method based on derivative domain responsivity correction, It is characterized in that The steps include: Set up N black bodies with different temperatures; Acquire an image of each black body through an infrared imaging device, and collect the response of the infrared detector of the infrared imaging device to the current black body temperature when acquiring each black body image; Based on the response of the infrared detector to the current black body temperature, the response curve function f(T; P) of each pixel to different black body temperatures is fitted, and the response curve function f(T; P) of each pixel is derived to obtain the response rate f′(T; P) of each pixel at any temperature. Correct the response rate f′(T; P) of each pixel so that the response rate f′(T; P) of each pixel is the same as the preset response rate, and record the response rate correction parameter set Q of each pixel during the correction process; Perform non-uniformity correction on the infrared image and output the corrected infrared image.

2. The non-uniformity correction method according to claim 1, It is characterized in that The response curve function f(T; P) is a quadratic polynomial curve obtained based on fitting, and its expression is shown in formula (1): f (T;P )=p 1 ×T 2 +p 2 ×T+p 3 (1) Among them, T is the black body temperature; P is the response curve parameter set of the current pixel to different black body temperatures; p1, p2, and p3 are all parameters in the response curve parameter set.

3. The non-uniformity correction method according to claim 1, It is characterized in that The response rate f′(T; P) of each pixel is corrected so that the response rate f′(T; P) of each pixel is the same as the preset response rate, including the following steps: Get the center point response rate f′ of the center point of the image c(T;P) ; Construct the center point response rate f′ c(T;P) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate f′ c(T;P) same.

4. The non-uniformity correction method according to claim 1, It is characterized in that The response rate f′(T; P) of each pixel is corrected so that the response rate f′(T; P) of each pixel is the same as the preset response rate, including the following steps: The full-image response mean value A of all pixels when the infrared imaging device acquires each black body image is calculated; The mean response curve f of the whole image is obtained by fitting the mean response A of all the whole images. m(T;A) , where T is the blackbody temperature; The mean response curve f for the whole graph m(T;A) Derivative, get the average response rate f' of the whole picture m(T;A) ; Construct the average response rate f' of the whole graph m(T;A) The response rate f′ of any point in the image x(T;P) The mapping relationship g between them makes the response rate f′ of any point in the image x(T;P) The average response rate of the whole picture f' m(T;A) same.

5. The non-uniformity correction method according to claim 1, It is characterized in that Performing non-uniformity correction on the infrared image and outputting the corrected infrared image specifically includes the following steps: Acquire an infrared image of the current target through an infrared imaging device, and obtain the current response rate of each pixel; The target temperature T is calculated based on the current response rate of each pixel; The current response rate of the current pixel is corrected according to the response rate correction parameter set Q of each pixel to obtain a nonlinear response curve after the non-uniformity of each pixel is corrected, and a corrected infrared image is output.

6. The non-uniformity correction method according to claim 5, It is characterized in that According to the response rate correction parameter set Q of each pixel, the current response rate of the corresponding pixel is corrected to obtain the nonlinear response curve after the non-uniformity of each pixel is corrected, including the following steps: pass The response rate f′ to the current pixel x x(T;P) Correction is made, where f xc (T) is the nonlinear response curve of the current pixel x after non-uniformity correction, g x (*) is the response rate f′ of the current pixel x x(T;P) and the central point response rate f′ c(T;P) Or the average response rate of the whole graph f' m(T;A) The mapping relationship between them.

7. The non-uniformity correction method according to claim 1, It is characterized in that Performing non-uniformity correction on the infrared image and outputting the corrected infrared image specifically includes the following steps: Obtain an infrared image of the current target through an infrared imaging device, and obtain the true response of each pixel based on the infrared detector; The target temperature T is calculated by the following formula: Where T is the target temperature obtained by inverse calculation; G is the actual response of the current pixel; Substitute the inversely calculated target temperature T and the actual response G of the current pixel into the following formula to obtain the corrected response G1 of the current pixel: G1=q 1 ×G+q 2 ×T+C Set the shutter temperature T s , shutter response G s Substitute into the following formula to obtain the corrected shutter response G2 of the current pixel: G2=q 1 ×G s +q 2 ×T s +C Each pixel is bias-corrected by the following formula to obtain the non-uniformity correction response value G3: G3=G1-G2=q 1 ×G+q 2 ×T+C-q 1 ×G s +q 2 ×T s +C=q 1 ×(G-G s )+q 2 ×(T-T s ); The corrected infrared image is output according to the non-uniformity correction response value G3 of each pixel to complete the non-uniformity correction.

8. The non-uniformity correction method according to claim 1, It is characterized in that After arranging the temperatures of all black bodies in descending or ascending order, the temperature interval between every two adjacent black body temperatures is the same.

9. The non-uniformity correction method according to claim 1, It is characterized in that Before acquiring the first blackbody image, the infrared imaging device must be placed in a constant temperature environment after being turned on until the temperature of the focal plane of the infrared detector becomes constant.

10. The non-uniformity correction method according to claim 1, It is characterized in that When an infrared imaging device acquires an image of any black body, the black body fills the entire imaging field of view.

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