Infrared scene quantitative radiance calculation method based on ray tracing module

Abstract

The present application relates to a kind of infrared scene quantitative radiance calculation methods based on light ray tracking module, comprising: obtaining target mask information image, the radiance image of infrared scene, depth information image and position information image, sensor position information, sensor field of view and sensor observation direction;Infrared scene is divided into several view cones according to the resolution of target radiance area image, wherein several view cones and the object surface in infrared scene intersect to form several face elements;The radiance of each face element at the sensor is calculated by the theorem of solid angle projection;The radiance of several face elements at the sensor is accumulated, and the radiance of infrared scene to the sensor is obtained.The method supports full scene, single target, multiple targets as radiation energy source, and can be applied to high complex infrared scene simulation work;Without additional data support, the radiance at the sensor can be calculated without performing redundant work.

Description

Technical Field

[0001] This invention belongs to the field of infrared analysis technology, specifically relating to a method for calculating quantitative irradiance in infrared scenes based on a ray tracing module. Background Technology

[0002] Infrared scene simulation technology is a computer-based technique used to simulate infrared radiation and heat transfer, and it is widely applied in the development, testing, and evaluation of infrared sensors and infrared imaging systems. Radiation and heat transfer are crucial physical processes in infrared scenes. Various infrared radiation and heat transfer models have been established, such as radiation thermodynamics models and radiation transfer equations. These models can be used to calculate the transmission process of infrared radiation, thereby generating radiation images and infrared scenes. To verify the accuracy and realism of the simulation, a realistic typical scene can be established and simulated using infrared scene simulation technology. Infrared sensors (such as infrared detectors and cameras) are used to monitor actual data in the real scene. The simulated data is then compared with the measured data for further verification, guiding practical work. The irradiance at the sensor location can be used as one of the indicators for assessing the accuracy of the simulation.

[0003] To calculate the irradiance generated at the sensor in the simulation scene, the existing technical solutions are as follows:

[0004] (1) For infrared extension calculation, the radiation calculation between infrared extension sources is transformed into radiation calculation between grid surface sources by dividing the surface of infrared extension sources into grid surface sources; by iterating through the grid surface sources, the irradiance buffer of the grid surface sources is accumulated; by calculating the multi-level irradiance buffer, the irradiance distribution of the infrared extension source surface is obtained.

[0005] (2) Considering the influence of changes in Earth-Sun distance, Earth's shadow area, and point source transmittance function on the calculation results, a method for calculating solar radiation illuminance at the entrance pupil of a satellite camera is provided, including: S1: obtaining the satellite's fixed-point longitude and local time; S2: calculating the solar incidence angle at the satellite's nadir; S3: determining whether the geostationary orbit satellite is currently in Earth's shadow area based on the solar incidence angle, the Earth's diameter, and the altitude of the geostationary orbit satellite; S4: calculating the Earth-Sun distance coefficient; S5: calculating the solar radiation illuminance at this time; S6: calculating the off-axis angle and azimuth angle of sunlight relative to the camera's line of sight of the geostationary orbit satellite; S7: calculating the solar radiation illuminance received at the entrance pupil of the geostationary orbit satellite camera.

[0006] (3) A method for calculating the spectral irradiance of a light source is provided. The method uses multiple filters to obtain a second measurement value of the light source at each preset wavelength and a first measurement value of the light source at each preset wavelength when there are no filters. The accurate value of the spectral irradiance of the light source is calculated by combining the first measurement value and the second measurement value, as well as the relationship between the contribution ratio of light of each wavelength other than the preset wavelength in the bandpass range of each filter to the spectral irradiance at the preset wavelength and the accurate value of the spectral irradiance at the preset wavelength.

[0007] (4) A method for relative measurement of stellar irradiance is provided, the method comprising the following steps: acquiring an image of a standard star; calculating the sum of the gray values ​​of the pixels in the stellar region of the image after removing the background as the gray value of the current standard star; calculating the atmospheric transmittance based on the angle of the current standard star from the zenith, and calculating the gray value of the current standard star outside the atmosphere based on the gray value of the current standard star and the atmospheric transmittance; obtaining the gray values ​​of multiple standard stars outside the atmosphere, and obtaining the irradiance of the corresponding standard star outside the atmosphere based on the star catalog data, and obtaining a fitting formula for irradiance and gray value; acquiring an image of the star to be measured, calculating the gray value of the star to be measured outside the atmosphere, and obtaining the irradiance based on the fitting formula.

[0008] However, the above technical solutions have the following drawbacks: they only perform calculations for a single infrared extended source radiation target; they only perform calculations for specific conditions and specific scenarios, which has significant limitations; they rely on hardware conditions to perform calculations on real scenarios and cannot be applied to simulation scenarios; and they require calculations based on data other than the target data. Summary of the Invention

[0009] To address the aforementioned problems in the existing technology, this invention provides a method for calculating quantitative irradiance in infrared scenes based on a ray tracing module. The technical problem to be solved by this invention is achieved through the following technical solution:

[0010] This invention provides a method for calculating quantitative irradiance in an infrared scene based on a ray tracing module, comprising the following steps:

[0011] The target mask information image obtained by the ray tracing module in the first rendering based on the first scene configuration file, the radiance image, depth information image and position information image of the infrared scene obtained by the second rendering based on the second scene configuration file, and the sensor position information, sensor field of view and sensor observation direction are also obtained.

[0012] The radiance image is marked using the target mask information image to obtain a target radiance region image;

[0013] The infrared scene is divided into several viewing cones according to the resolution of the target radiance region image, wherein the several viewing cones intersect with the object surface in the infrared scene to form several surface elements;

[0014] By combining the target radiance region image, the depth information image, the position information image, the sensor position information, the sensor field of view, and the sensor observation direction, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem;

[0015] The irradiance generated by several surface elements at the sensor is summed to obtain the irradiance generated by the infrared scene on the sensor.

[0016] In one embodiment of the present invention, the second scene configuration file has different scene lighting conditions than the first scene configuration file;

[0017] The sensor's relative position to the infrared scene is the same during both the first and second rendering.

[0018] In one embodiment of the present invention, acquiring sensor position information, sensor field of view, and sensor observation direction includes:

[0019] The sensor location information, sensor field of view, and sensor observation direction are obtained from the first scene configuration file or the second scene configuration file.

[0020] In one embodiment of the present invention, the radiance image is marked using the target mask information image to obtain a target radiance region image, including:

[0021] The non-zero value regions in the radiance image are marked using the target mask information image to obtain the target radiance region image.

[0022] In one embodiment of the present invention, the infrared scene is divided into several viewing cones according to the resolution of the target radiance region image, and the several viewing cones intersect with the object surface in the infrared scene to form several surface elements, including:

[0023] The rays emitted by the sensor that reach the four corners of each pixel in the target radiance region image form a quadrangular pyramid. Multiple quadrangular pyramids are formed by the rays reaching multiple pixels, thus obtaining the plurality of viewing cones.

[0024] The plurality of viewing cones intersect with the surfaces of objects in the infrared scene to form a plurality of quadrilaterals;

[0025] Each quadrilateral is approximated as a quadrilateral with four points coplanar, and the plurality of surface elements are formed by a plurality of quadrilaterals with four points coplanar.

[0026] In one embodiment of the present invention, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem by combining the target radiance region image, the depth information image, the position information image, the sensor position information, the sensor field of view, and the sensor observation direction. This includes:

[0027] The cosine of the angle between the sensor's observation direction and the perpendicular line to the visual cone is calculated by combining the location information image and the sensor's location information.

[0028] The length and width of the target quadrilateral are calculated by combining the radiance image and the sensor field of view, wherein the target quadrilateral is a plane perpendicular to the perpendicular line of the viewing cone, and the target quadrilateral passes through the intersection of the perpendicular line of the viewing cone and the surface element;

[0029] The first solid angle generated by the target quadrilateral on the sensor is calculated by combining the length and width of the target quadrilateral and the depth information image; wherein, the first solid angle generated by the target quadrilateral on the sensor is equal to the second solid angle generated by the surface element on the sensor;

[0030] By combining the target radiance region image, the cosine value of the included angle, and the second solid angle, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem.

[0031] In one embodiment of the present invention, calculating the cosine of the angle between the sensor's observation direction and the perpendicular line to the viewing cone, combining the location information image and the sensor's location information, includes:

[0032] The perpendicular line of the visual cone is obtained by subtracting the position information image from the sensor position information.

[0033] Calculate the cosine of the angle between the sensor's observation direction and the perpendicular line to the cone of vision:

[0034]

[0035] Where cosθ is the cosine of the angle between the sensor's observation direction and the perpendicular line to the cone of vision. For the sensor's observation direction, It is the perpendicular line to the visual cone.

[0036] In one embodiment of the present invention, calculating the length and width of the target quadrilateral by combining the radiance image and the sensor field of view includes:

[0037] Calculate the offset of a pixel in the radiance image relative to the center of the image:

[0038]

[0039]

[0040] Where (i,j) are the pixel position coordinates, m is the number of pixels in the width of the scene radiance image, n is the number of pixels in the height of the scene radiance image, and (i',j') is the offset of the pixel position coordinates (i,j) relative to the center of the image.

[0041] The lateral and longitudinal field of view of each frustum are calculated based on the offset, the sensor field of view, and the resolution of the radiance image:

[0042]

[0043]

[0044] Where, Δθ i Let Δθ be the lateral field of view of the cone. j D is the longitudinal field of view of the viewing cone. i D represents the sensor's lateral field of view. j This refers to the longitudinal field of view of the sensor.

[0045] Using the properties of right triangles, the length of the target quadrilateral is calculated based on the lateral field of view of the viewing cone and the perpendicular line of the viewing cone, and the width of the target quadrilateral is calculated based on the longitudinal field of view of the viewing cone and the perpendicular line of the viewing cone.

[0046] In one embodiment of the present invention, calculating the first solid angle of the target quadrilateral to the sensor by combining the length and width of the target quadrilateral and the infrared scene depth information image includes:

[0047] The distance between the sensor and the intersection point is obtained from the depth information image;

[0048] Calculate the first solid angle produced by the target quadrilateral on the sensor based on the length of the target quadrilateral, the width of the target quadrilateral, and the distance:

[0049]

[0050] Where a is the length of the target quadrilateral, b is the width of the target quadrilateral, and d is the distance between the sensor and the intersection point.

[0051] In one embodiment of the present invention, the irradiance generated by each of the surface elements at the sensor is:

[0052] E=LΔΩ s cosθ

[0053] Where E is the irradiance, L is the radiance of each surface element, and ΔΩ s Let θ be the first solid angle generated by the target quadrilateral on the sensor, and cosθ be the cosine of the angle between the sensor's observation direction and the perpendicular line of the viewing cone.

[0054] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0055] This invention calculates infrared scene irradiance from images obtained under different scene configuration files. The target radiation source can be controlled by adjusting the scene configuration file, thus supporting the use of the entire scene, a single target, or multiple targets as irradiance sources. This makes it suitable for highly complex infrared scene simulations. Furthermore, it can directly use image data generated from infrared scene simulations to calculate the irradiance of each surface element without requiring additional data support or unnecessary processing. Additionally, by dividing the infrared scene into several view frustums and forming several surface elements, and calculating and summing the irradiance of each surface, the results are highly accurate and closely match real-world measured data. Attached Figure Description

[0056] Figure 1 A flowchart illustrating a method for calculating quantitative irradiance in an infrared scene based on a ray tracing module, provided in an embodiment of the present invention;

[0057] Figure 2 A flowchart illustrating another method for calculating quantitative irradiance in an infrared scene based on a ray tracing module, provided in an embodiment of the present invention;

[0058] Figure 3 A schematic diagram showing an infrared scene divided into several view frustums according to an embodiment of the present invention;

[0059] Figure 4 This is a schematic diagram of a view frustum provided in an embodiment of the present invention. Detailed Implementation

[0060] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0061] Example 1

[0062] Please see Figure 1 and Figure 2 , Figure 1 This is a flowchart illustrating a method for calculating quantitative irradiance in an infrared scene based on a ray tracing module, as provided in an embodiment of the present invention. Figure 2This is a flowchart illustrating another method for calculating quantitative irradiance in an infrared scene based on a ray tracing module, provided in an embodiment of the present invention. The method includes the following steps:

[0063] S1. Obtain the target mask information image obtained by the ray tracing module in the first rendering based on the first scene configuration file, and the radiance image, depth information image and position information image of the infrared scene obtained by the second rendering based on the second scene configuration file, and obtain the sensor position information, sensor field of view and sensor observation direction.

[0064] Specifically, the ray tracing module, also known as the ray tracing generator, is a high-precision simulation system for complex scenes based on physically based rendering principles and global illumination models. It uses offline rendering to generate quantitative high-fidelity images of visible light, infrared short, medium, and long wavelengths, and hyperspectral data. In this embodiment, the ray tracing module, building upon the PBRT module, converts the visible spectrum into the infrared spectrum and incorporates depth and position information parameters. This enables the following functions: based on physically based rendering methods, it tracks and records the propagation and scattering behavior of light, establishing a quantitative model that comprehensively considers the reflection / scattering processes of light on object surfaces. It combines physical parameters such as the object's surface emissivity, reflectivity, bidirectional reflection distribution function (BRDF), and temperature to achieve quantitative rendering. For infrared radiation calculations, the ray tracing module in this embodiment extends the following models beyond the PBRT module: an ideal blackbody spectral radiance model, a spectral calculation characterization model, a material surface spectral reflectance model, and a spectral data sampling model. The ideal blackbody spectral radiance model is the foundation for calculating the apparent radiation of an object. By designing spectral characterization objects, the spectral data calculation function in the ray tracing rendering pipeline in the infrared band is realized. It should be noted that the ray tracing module in this embodiment can be implemented by combining the basic knowledge of ray tracing with the existing PBRT module.

[0065] Furthermore, firstly, the ray tracing module performs a first rendering based on the first scene configuration file to obtain the target mask information image. This target mask information image is a binary image, where non-zero values ​​represent pixels belonging to the radiation source. When all pixel grayscale values ​​in this binary image are not 0, it is considered that the entire scene is used as the energy source for the irradiance at the sensor. Therefore, the target radiation source can be controlled by controlling the scene configuration file, thereby supporting the use of the entire scene, a single target, or multiple targets as radiation energy sources.

[0066] Then, the ray tracing module performs a second rendering based on the second scene configuration file to obtain the radiance image, depth information image, and position information image of the entire infrared scene. The scene lighting conditions in the first and second scene configuration files are different; however, the relative position of the sensor to the infrared scene is the same during both the first and second renderings.

[0067] Next, the target mask information image is acquired, and the non-zero value regions of the target mask information image are marked. The marked parts are considered to be the energy source of the irradiance at the sensor, and the non-zero value regions are collectively referred to as the target scene. The radiance image, depth information image, and position information image of the infrared scene are acquired. The target mask information image, radiance image, depth information image, and position information image have the same resolution, the sensor and the scene have the same relative position, and the grayscale value of each pixel is physically real, that is, it represents the real physical value; each pixel in the scene contains a set of information consisting of radiance, depth, and position coordinates.

[0068] Next, obtain the first scene configuration file or the second scene configuration file. Since the scene lighting conditions of the first scene configuration file and the second scene configuration file are different, but the other parameters are the same, the sensor position information, sensor field of view and sensor observation direction can be obtained from either scene configuration file.

[0069] S2. Mark the radiance image using the target mask information image to obtain the target radiance region image.

[0070] Specifically, the target mask information image is essentially a radiance image. The non-zero value regions of the radiance image of the infrared scene can be marked using the target mask information image to obtain the target radiance region image.

[0071] S3. Divide the infrared scene into several viewing cones according to the resolution of the target radiance area image. Among them, several viewing cones intersect with the object surface in the infrared scene to form several surface elements.

[0072] Step S3 specifically includes the following steps: the rays emitted by the sensor that reach the four corners of each pixel in the target radiance area image form a quadrangular pyramid, and the rays that reach multiple pixels form multiple quadrangular pyramids to obtain several viewing cones; the several viewing cones intersect with the object surface in the infrared scene to form several quadrilaterals; each quadrilateral is approximated as a quadrilateral with four points coplanar, and several surface elements are formed from several quadrilaterals with four points coplanar.

[0073] Specifically, the process by which the radiation energy of the target infrared scene acts on the sensor can be viewed as the cumulative effect of the small facets represented by each pixel in the radiance image at the sensor. That is, the entire simulated scene is divided into m×n frustums according to the resolution of the radiance image. The segmentation method is as follows: Figure 3 and Figure 4 As shown, Figure 3 This is a schematic diagram showing an infrared scene divided into several view frustums, as provided in an embodiment of the present invention. Figure 4 This is a schematic diagram of a view frustum provided in an embodiment of the present invention. Figure 3 In this diagram, m represents the number of pixels in the width of the scene radiance image, n represents the number of pixels in the height of the scene radiance image, and O is the starting point of the field of view, i.e., the sensor position. Rays emanating from O and reaching the four corners of the image pixels form a square pyramid. Figure 4 The central cone. Figure 4 In the diagram, quadrilateral efpq represents the intersection of the viewing frustum with the surface of an object in the real infrared scene. When the radiance image resolution is sufficiently high, it is approximated that the four points of efpq are coplanar, forming a surface element; point S is the intersection of the perpendicular bisector of the viewing frustum and quadrilateral efpq, and vector... Let S be the normal to efpq. The target quadrilateral abcd is the portion of the plane passing through point S and perpendicular to the view frustum OS that is intercepted by the view frustum. The target quadrilateral abcd is a rectangle.

[0074] S4. Combining the target radiance area image, depth information image, position information image, sensor position information, sensor field of view, and sensor observation direction, calculate the irradiance generated at the sensor for each surface element using the solid angle projection theorem.

[0075] Specifically, as shown in step S3, the solid angle produced by quadrilateral abcd at point O is equal to the solid angle produced by quadrilateral efpq at point O. That is, the first solid angle produced by the target quadrilateral at the sensor is equal to the second solid angle produced by the surface element at the sensor. Therefore, according to the solid angle projection theorem, the irradiance produced by quadrilateral qfpq, i.e., each surface element, at sensor O is:

[0076] E=LΔΩ s cosθ

[0077] Where E is the irradiance, L is the radiance of each surface element efpq, and L can be obtained from the image of the target radiance region, ΔΩ s Let θ be the first solid angle generated by the target quadrilateral on the sensor, and cosθ be the cosine of the angle between the sensor's observation direction and the perpendicular line OS of the view frustum.

[0078] From the above formula, we can see that ΔΩ s And cosθ is unknown, where the first solid angle ΔΩ produced by the target quadrilateral on the sensor is unknown. s It is given by the following formula:

[0079]

[0080] Where a is the length of the target quadrilateral abcd, b is the width of the target quadrilateral abcd, and d is the distance between the sensor and the intersection point.

[0081] Therefore, step S4 specifically includes the following steps:

[0082] S401. Calculate the cosine of the angle between the sensor's observation direction and the perpendicular line to the view frustum by combining the position information image and the sensor's position information.

[0083] First, obtain the sensor's viewing direction from the scene configuration file, denoted as...

[0084] Next, the perpendicular line OS of the view frustum is obtained by subtracting the location information image from the sensor location information. In this embodiment, the straight line OS (which is a vector, and the OS is different for each pixel vector) is obtained by subtracting the scene location information and the sensor location information, denoted as . The scene location information is obtained from the location information image.

[0085] Finally, by and Calculate the cosine of the angle between the sensor's viewing direction and the perpendicular line to the view frustum:

[0086]

[0087] Where cosθ is the cosine of the angle between the sensor's observation direction and the perpendicular line to the cone of vision. For the sensor's observation direction, It is the perpendicular line to the visual cone.

[0088] S402. Calculate the length and width of the target quadrilateral by combining the radiance image and the sensor field of view, wherein the target quadrilateral is a plane perpendicular to the perpendicular line of the viewing cone, and the target quadrilateral passes through the intersection of the perpendicular line of the viewing cone and the surface element.

[0089] Specifically, settings Figure 3 If the coordinates of the lower left corner of the image are (0,0) and the coordinates of the upper right corner are (m,n), then the side length of the target quadrilateral abcd in the view frustum in the image can be obtained from the pixel index, the sensor field of view, and the image resolution.

[0090] First, calculate the offset of a pixel in the radiance image relative to the image's center:

[0091]

[0092]

[0093] Where (i,j) are the position coordinates, m is the number of pixels in the width of the scene radiance image, n is the number of pixels in the height of the scene radiance image, and (i',j') is the offset of the position coordinates (i,j) relative to the center of the image.

[0094] Then, the lateral and longitudinal field of view angles of each frustum are calculated based on the offset, sensor field of view angle, and resolution of the radiance image. Specifically, for the frustum corresponding to the pixel at position coordinates (i,j), its lateral and longitudinal field of view angles are obtained by the following formula:

[0095]

[0096]

[0097] Where, Δθ i Let Δθ be the lateral field of view of the cone. j D is the longitudinal field of view of the viewing cone. i D represents the sensor's lateral field of view. j This represents the longitudinal field of view of the sensor.

[0098] Next, using the properties of right triangles, the length of the target quadrilateral is calculated based on the lateral field of view of the viewing cone and the perpendicular line of the viewing cone, and the width of the target quadrilateral is calculated based on the longitudinal field of view of the viewing cone and the perpendicular line of the viewing cone.

[0099] S403. Calculate the first solid angle generated by the target quadrilateral on the sensor by combining the length, width, and depth information of the target quadrilateral image; wherein, the first solid angle generated by the target quadrilateral on the sensor is equal to the second solid angle generated by the surface element on the sensor.

[0100] First, the distance d between the sensor and the intersection point is obtained from the depth information image, that is, the distance from point O to point S.

[0101] Then, the first solid angle ΔΩ generated by the target quadrilateral on the sensor is combined with the target quadrilateral. s The calculation formula calculates the first solid angle ΔΩ produced by the target quadrilateral on the sensor based on the length, width, and distance of the target quadrilateral. s .

[0102] S404. Combining the target radiance region image, the cosine of the included angle, and the second solid angle, the irradiance generated at the sensor by each surface element is calculated using the solid angle projection theorem.

[0103] Specifically, combining the cosθ calculated in step S401 and the ΔΩ calculated in step S403... s According to the formula E=LΔΩ s The irradiance generated at the sensor by each surface element can be obtained by using cosθ.

[0104] S5. The irradiance generated by several surface elements at the sensor is summed to obtain the irradiance generated by the infrared scene on the sensor.

[0105] Specifically, the pixels marked as the target infrared scene are traversed, and the irradiance of the surface element in a single view frustum at the sensor is obtained using the solid angle projection theorem. Finally, the irradiance generated by the above surface elements is accumulated to obtain the irradiance generated by the infrared scene on the sensor.

[0106] This embodiment utilizes images obtained by the ray tracing module under different scene configuration files to calculate infrared scene irradiance. The data is accurate and reliable. The target radiation source can be controlled by controlling the scene configuration file, thus supporting the use of the entire scene, a single target, or multiple targets as radiation energy sources. It is suitable for highly complex infrared scene simulations. At the same time, the ray tracing module can directly use the image data generated by the infrared scene simulation to calculate the irradiance generated by each surface element without additional data support or unnecessary work. Furthermore, by dividing the infrared scene into several view frustums and forming several surface elements, the irradiance of each surface is calculated and accumulated, resulting in high accuracy and good agreement with the measured data of the real scene.

[0107] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for calculating quantitative irradiance in infrared scenes based on a ray tracing module, characterized in that, Including the following steps: The target mask information image obtained by the ray tracing module in the first rendering based on the first scene configuration file, the radiance image, depth information image and position information image of the infrared scene obtained by the second rendering based on the second scene configuration file, and the sensor position information, sensor field of view and sensor observation direction are also obtained. The radiance image is marked using the target mask information image to obtain a target radiance region image; The infrared scene is divided into several viewing cones according to the resolution of the target radiance region image, wherein the several viewing cones intersect with the object surface in the infrared scene to form several surface elements; By combining the target radiance region image, the depth information image, the position information image, the sensor position information, the sensor field of view, and the sensor observation direction, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem; The irradiance generated by several surface elements at the sensor is summed to obtain the irradiance generated by the infrared scene on the sensor.

2. The method for calculating quantitative irradiance of an infrared scene based on a ray tracing module according to claim 1, characterized in that, The second scene configuration file has different scene lighting conditions than the first scene configuration file; The sensor's relative position to the infrared scene is the same during both the first and second rendering.

3. The method for calculating quantitative irradiance in an infrared scene based on a ray tracing module according to claim 1, characterized in that, Acquire sensor position information, sensor field of view, and sensor viewing direction, including: The sensor location information, sensor field of view, and sensor observation direction are obtained from the first scene configuration file or the second scene configuration file.

4. The method for calculating quantitative irradiance in an infrared scene based on a ray tracing module according to claim 1, characterized in that, The radiance image is marked using the target mask information image to obtain a target radiance region image, including: The non-zero value regions in the radiance image are marked using the target mask information image to obtain the target radiance region image.

5. The method for calculating quantitative irradiance of an infrared scene based on a ray tracing module according to claim 1, characterized in that, The infrared scene is divided into several viewing cones according to the resolution of the target radiance region image. These viewing cones intersect with the surfaces of objects in the infrared scene to form several surface elements, including: The rays emitted by the sensor that reach the four corners of each pixel in the target radiance region image form a quadrangular pyramid. Multiple quadrangular pyramids are formed by the rays reaching multiple pixels, thus obtaining the plurality of visual cones. The plurality of viewing cones intersect with the surfaces of objects in the infrared scene to form a plurality of quadrilaterals; Each quadrilateral is approximated as a quadrilateral with four points coplanar, and the plurality of surface elements are formed by a plurality of quadrilaterals with four points coplanar.

6. The method for calculating quantitative irradiance in an infrared scene based on a ray tracing module according to claim 1, characterized in that, Combining the target radiance region image, the depth information image, the position information image, the sensor position information, the sensor field of view, and the sensor observation direction, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem, including: The cosine of the angle between the sensor's observation direction and the perpendicular line to the view cone is calculated by combining the location information image and the sensor's location information. The length and width of the target quadrilateral are calculated by combining the radiance image and the sensor field of view, wherein the target quadrilateral is a plane perpendicular to the perpendicular line of the viewing cone, and the target quadrilateral passes through the intersection of the perpendicular line of the viewing cone and the surface element; The first solid angle generated by the target quadrilateral on the sensor is calculated by combining the length and width of the target quadrilateral and the depth information image; wherein, the first solid angle generated by the target quadrilateral on the sensor is equal to the second solid angle generated by the surface element on the sensor; By combining the target radiance region image, the cosine value of the included angle, and the second solid angle, the irradiance generated by each surface element at the sensor is calculated using the solid angle projection theorem.

7. The method for calculating quantitative irradiance of an infrared scene based on a ray tracing module according to claim 6, characterized in that, Calculating the cosine of the angle between the sensor's viewing direction and the perpendicular to the view frustum by combining the location information image and the sensor's location information includes: The perpendicular line of the visual cone is obtained by subtracting the position information image from the sensor position information. Calculate the cosine of the angle between the sensor's observation direction and the perpendicular line to the cone of vision: Where cosθ is the cosine of the angle between the sensor's observation direction and the perpendicular line to the cone of vision. For the sensor's observation direction, It is the perpendicular line to the visual cone.

8. The method for calculating quantitative irradiance of an infrared scene based on a ray tracing module according to claim 6, characterized in that, The calculation of the length and width of the target quadrilateral by combining the radiance image and the sensor's field of view includes: Calculate the offset of a pixel in the radiance image relative to the center of the image: Where (i,j) are the pixel position coordinates, m is the number of pixels in the width of the scene radiance image, n is the number of pixels in the height of the scene radiance image, and (i',j') is the offset of the pixel position coordinates (i,j) relative to the center of the image. The lateral and longitudinal field of view of each cone are calculated based on the offset, the sensor field of view, and the resolution of the radiance image: Where, Δθ i Let Δθ be the lateral field of view of the cone. j D is the longitudinal field of view of the viewing cone. i D represents the sensor's lateral field of view. j This refers to the longitudinal field of view of the sensor. Using the properties of right triangles, the length of the target quadrilateral is calculated based on the lateral field of view of the viewing cone and the perpendicular line of the viewing cone, and the width of the target quadrilateral is calculated based on the longitudinal field of view of the viewing cone and the perpendicular line of the viewing cone.

9. The method for calculating quantitative irradiance in an infrared scene based on a ray tracing module according to claim 6, characterized in that, Calculating the first solid angle of the target quadrilateral relative to the sensor by combining the length and width of the target quadrilateral and the infrared scene depth information image includes: The distance between the sensor and the intersection point is obtained from the depth information image; Calculate the first solid angle of the target quadrilateral to the sensor based on the length of the target quadrilateral, the width of the target quadrilateral, and the distance: Where a is the length of the target quadrilateral, b is the width of the target quadrilateral, and d is the distance between the sensor and the intersection point.

10. The method for calculating quantitative irradiance of an infrared scene based on a ray tracing module according to claim 1 or 6, characterized in that, The irradiance generated by each of the surface elements at the sensor is: E=LΔΩ s cosθ Where E is the irradiance, L is the radiance of each surface element, and ΔΩ s Let θ be the first solid angle generated by the target quadrilateral on the sensor, and cosθ be the cosine of the angle between the sensor's observation direction and the perpendicular line of the viewing cone.

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