A method and system for improving the definition of a terrain map in a ground-hugging visual simulation

Abstract

This invention belongs to the field of visual simulation technology, and relates to a method and system for improving the clarity of terrain maps in ground-level visual simulation. The method includes: acquiring satellite images, high-definition terrain maps, and the current altitude of the aircraft above the ground. h Based on the current altitude of the aircraft above the ground h Determine the blending factor of the terrain maps to be blended T According to the height h Adjust the parameters of the high-resolution terrain map to obtain a preprocessed high-resolution terrain map; based on the blending factor T The satellite imagery and the preprocessed high-resolution terrain map are mixed to improve the clarity of the resulting target terrain map. This invention provides a method for improving terrain map clarity in ground-hugging visual simulations. By utilizing image mixing technology, it significantly enhances terrain map clarity and achieves excellent display results.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of visual simulation, and relates to a method and system for improving the clarity of terrain mapping in ground-hugging visual simulation. BACKGROUND

[0002] In the field of flight simulation, a realistic and interactive terrain system can be established using visual simulation technology, and has the characteristics of reliability, non-destructiveness, repeatability, safety, economy, and no restriction by weather conditions and airspace.

[0003] A commonly used method in the industry is to create a model file using elevation data to form a three-dimensional real terrain, use real satellite photos as model mapping to jointly form a terrain database, and load and present in visual simulation. However, since the existing method changes the clarity of the terrain system by using satellite photos of different levels, when the plane takes off and flies at a high altitude, the existing method presents unsatisfactory results. However, when the plane flies close to the ground, such as in helicopter ground-hugging flight simulation, even if the highest level satellite photo is used as the terrain mapping, the resolution of the satellite mapping is still relatively low, which is poor in display effect to the human eye. In addition, using satellite photo mapping requires TB-level elevation and satellite photo data and high-performance hardware to support. However, since high-level satellite photos have large data volume, occupy large storage space, and have high performance requirements for hardware resources. Therefore, how to use limited resources in ground-hugging visual simulation while ensuring excellent presentation effect has become a difficulty in software development. SUMMARY

[0004] In view of the technical problem of poor display effect of terrain mapping in existing ground-hugging visual simulation, the present application provides a method for improving the clarity of terrain mapping in ground-hugging visual simulation, which greatly improves the clarity of terrain mapping and has good display effect by using image mixing technology.

[0005] To achieve the above purpose, the technical solution adopted by the present application is to use image mixing technology, adjust the mixing factor according to the height from the ground, mix the real satellite photo with the high-definition terrain mapping, and retain the details of the real satellite photo to greatly improve the clarity of the terrain mapping. The specific scheme is as follows:

[0006] A method for improving the clarity of terrain mapping in ground-hugging visual simulation, characterized in that it comprises the following steps:

[0007] Obtain satellite photos, high-definition terrain mapping, and the height h of the current plane from the ground;

[0008] Determine the mixing factor T of the terrain mapping to be mixed according to the height h of the current plane from the ground;

[0009] determining parameters of the high-definition terrain map according to the height h, obtaining a preprocessed high-definition terrain map;

[0010] mixing the satellite photo and the preprocessed high-definition terrain map based on the mixing factor T, obtaining a high-definition target terrain map.

[0011] Further limitation, the determination of the height h of the current aircraft from the ground is specifically:

[0012] a ray is emitted vertically downward from the position of the aircraft;

[0013] When the ray collides with the terrain, the collision point coordinates can be obtained, which include the absolute height of the collision point;

[0014] The height h of the current aircraft from the ground is obtained by subtracting the absolute height of the collision point from the absolute height of the aircraft.

[0015] Further limitation, the determination of the mixing factor T of the terrain map to be mixed according to the height h of the current aircraft from the ground specifically includes:

[0016] presetting a height threshold Ht according to the actual application scenario;

[0017] setting a mixing coefficient M based on the actual needs of the user;

[0018] determining the mixing factor T of the terrain map to be mixed according to the height h of the current aircraft from the ground, the preset height threshold Ht and the mixing coefficient M.

[0019] Further limitation, the determination of the parameters of the high-definition terrain map according to the height h specifically includes:

[0020] obtaining the side length w of the terrain to be mapped, and calculating the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground;

[0021] determining the minimum tiling times Tmin and the maximum tiling times Tmax according to the preset resolution of the high-definition terrain map;

[0022] determining the parameters of the high-definition terrain map:

[0023] If the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground is less than the minimum tiling times Tmin, the parameters of the high-definition terrain map take the minimum tiling times Tmin;

[0024] If the ratio of the side length dimension w of the terrain to be mapped to the height h of the current aircraft from the ground is greater than the maximum tiling number Tmax, the parameter of the high-definition terrain map takes the maximum tiling number Tmax;

[0025] If the ratio of the side length dimension w of the terrain to be mapped to the height h of the current aircraft from the ground is between the minimum tiling number Tmin and the maximum tiling number Tmax, the parameter of the high-definition terrain map takes the ratio of the side length dimension w of the terrain to the height h of the current aircraft from the ground.

[0026] According to the determined parameter of the high-definition terrain map, a preprocessed high-definition terrain map is obtained.

[0027] Further limited, the mixing of the satellite photo and the preprocessed high-definition terrain map specifically includes:

[0028] Respectively select a pixel point at any position of the satellite photo and a pixel point at any position of the preprocessed high-definition terrain map, the positions match on the satellite photo and on the preprocessed high-definition terrain map;

[0029] According to the mixing factor T, the pixel color value at any position of the satellite photo and the pixel color value at any position of the preprocessed high-definition terrain map are mixed to obtain the final color value of the pixel at the corresponding position on the terrain to be mapped.

[0030] Repeat the above steps until all positions of the pixel points in the satellite photo and all positions of the pixel points in the preprocessed high-definition terrain map are traversed.

[0031] Obtain a target terrain map.

[0032] Further limited, the mixing of the satellite photo and the preprocessed high-definition terrain map specifically includes:

[0033] The final color value C of the pixel at any position is calculated according to the following formula:

[0034] C = a (1-T) + b x T

[0035] Wherein: T is a mixing factor, a is the color value of the corresponding pixel on the satellite photo, and b is the color value of the corresponding pixel on the high-definition terrain map.

[0036] A system for improving the clarity of terrain mapping in ground view simulation, comprising:

[0037] A data acquisition module for acquiring a satellite photo, a high-definition terrain map, and the height h of the current aircraft from the ground.

[0038] The mixed factor generation module is used for generating a mixed factor of the terrain map to be mixed according to the height h of the current airplane from the ground;

[0039] The image preprocessing module is used for adjusting the parameters of the high-definition terrain map according to the height h of the current airplane from the ground;

[0040] The image mixing module is used for mixing the satellite photo and the preprocessed high-definition terrain map according to the mixed factor to obtain a high-definition target terrain map.

[0041] Further limited, the image preprocessing module comprises:

[0042] The data calculation module is used for calculating the ratio of the terrain side length dimension w to the height h of the current airplane from the ground and feeding back the calculation result to the data judgment module;

[0043] The data judgment module is used for judging the size of the ratio of the terrain side length dimension w to the height h of the current airplane from the ground according to the calculation result fed back by the data calculation module and feeding back the judgment result to the parameter selection module of the high-definition terrain map;

[0044] The parameter selection module of the high-definition terrain map is used for selecting the parameters of the high-definition terrain map according to the judgment result fed back by the data judgment module.

[0045] The beneficial effects of the present application are:

[0046] Compared with the prior art, the method of the present application mixes the high-definition terrain map with high resolution and the satellite photo with low resolution in the ground view simulation, combines the mixed factor and the preprocessed high-definition terrain map according to the calculation, retains the details of the satellite photo, and obtains the target terrain map with high resolution, so as to improve the definition of the terrain map. The specific performance is:

[0047] 1. The method uses the image mixing technology, calculates and adjusts the mixed factor according to the height of the current airplane from the ground, mixes the real satellite photo and the high-definition terrain map according to the proportion of the mixed factor, retains the details of the satellite photo, and greatly improves the definition of the terrain map.

[0048] 2. The method uses the image mixing technology, calculates and adjusts the mixed factor according to the height of the current airplane from the ground, mixes the real satellite photo and the high-definition terrain map according to the proportion of the mixed factor, obtains the high-definition terrain map without using high-level satellite photos, reduces the level requirement of the satellite photo, reduces the data amount of the satellite photo, occupies small space, saves resources, and reduces the hardware performance.

[0049] 3、The present application fully considers the size of the map terrain and the current height of the airplane when determining the parameter of the number of repeated tiling, so that the high-definition terrain map has high resolution when applied to the terrain, thereby achieving the best visual effect and improving the clarity of the final mixed map. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 A terrain map method provided by the present application is shown in the figure;

[0051] Figure 2 A method for adjusting the parameters of the high-definition terrain map of the present application is shown in the figure;

[0052] Figure 3 A terrain map system provided by the present application is shown in the figure;

[0053] Figure 4 An image preprocessing module of the present application is shown in the figure;

[0054] Figure 5 A satellite photo obtained;

[0055] Figure 6 A high-definition terrain map obtained;

[0056] Figure 7 A satellite map effect diagram before mixing;

[0057] Figure 8 An effect diagram after mixing the map. DETAILED DESCRIPTION

[0058] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the present application will be described clearly and completely below in conjunction with the drawings of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without any creative effort fall within the scope of protection of the present application.

[0059] Unless otherwise defined, the technical terms or scientific terms used in the present application should be understood as the general meaning understood by those of ordinary skill in the art to which the present application belongs. The similar words such as “include” or “contain” and the like used in the present application mean that the elements or objects before the words cover the elements or objects listed after the words and their equivalents, without excluding other elements or objects.

[0060] Embodiment 1

[0061] Reference Figure 1 A method for improving the clarity of terrain map in the ground view simulation, comprising the following steps.

[0062] The method can be used in different three-dimensional engines, and the following is an example of the Unity engine.

[0063] 1) Obtain satellite photos, high-definition terrain maps, and the current height h of the plane from the ground.

[0064] In a three-dimensional scene, the object's current height is involved in the object's coordinates. Here, the height is the absolute height, but due to the undulations of the terrain, other methods are needed to obtain the current height from the ground.

[0065] In implementation, the physical collision feature in the Unity engine is used to vertically emit a ray downward from the position of the plane. When the ray collides with the terrain, the coordinates of the collision point can be obtained, which contains the absolute height of the collision point. The current height h of the plane from the ground is obtained by subtracting the absolute height of the collision point from the absolute height of the plane.

[0066] 2) Calculate the blending factor of the high-definition terrain map according to the height h of step 1).

[0067] The current height h of the plane from the ground determines whether image blending is needed and the blending ratio. In general, the lower the height, the higher the proportion of high-definition terrain maps and the lower the proportion of satellite photos. The higher the height, the lower the proportion of high-definition terrain maps and the higher the proportion of satellite photos.

[0068] A blending factor T is introduced, with a value range of [0, 1], i.e. when T = 0, the satellite photo is used as the terrain map; when T = 1, the high-definition terrain map is used as the terrain map; when 0 < T < 1, the satellite photo and the high-definition terrain map are blended according to the blending factor T as the terrain map.

[0069] In order to obtain an accurate blending factor, a height threshold Ht is preset according to the actual application scenario, and a blending coefficient M is set based on the actual needs of the user. The current blending factor T of the high-definition terrain map is determined based on the current height h of the plane from the ground, the preset height threshold Ht, and the blending coefficient M.

[0070] Image blending is needed when h < Ht; when h = 0, the blending factor is 1, and at this time the high-definition terrain map is used entirely, but in actual application scenarios, the terrain map cannot retain the details in the satellite photo if it is completely used as a high-definition terrain map, such as roads and farmland. Therefore, in order to avoid this situation, a blending coefficient M is introduced when determining the blending factor T, and M is a constant less than 1.

[0071] In implementation, the blending coefficient M is close to but not equal to 1, at this time the clarity of the terrain map is improved while retaining some details in the real satellite photo, achieving the best presentation effect.

[0072] Preferably, M takes 0.7-0.9.

[0073] The first calculation method of the mixing factor T is as follows.

[0074]

[0075] Specifically, the height threshold Ht is set to 100 meters, and the current aircraft height from the ground is 10 meters; the mixing coefficient M is set to 0.7, and the mixing factor T is calculated as 0.69 using the above formula (1), so the final terrain map is composed of 69% high-definition terrain map and 31% satellite photo map.

[0076] When the mixing coefficient M is set to 0.9, the mixing factor T is calculated as 0.89 using the above formula (1), so the final terrain map is composed of 89% high-definition terrain map and 11% satellite photo map.

[0077] The second calculation method of the mixing factor T is as follows.

[0078]

[0079] Specifically, the height threshold Ht is set to 100 meters, and the current aircraft height from the ground is 10 meters; the mixing coefficient M is set to 0.7, and the mixing factor T is calculated as 0.63 using the above formula (2), so the final terrain map is composed of 63% high-definition terrain map and 37% satellite photo map.

[0080] When the mixing coefficient M is set to 0.9, the mixing factor T is calculated as 0.81 using the above formula (2), so the final terrain map is composed of 81% high-definition terrain map and 19% satellite photo map.

[0081] 3) Determine the parameters of the high-definition terrain map according to the height h, obtain the preprocessed high-definition terrain map, and ensure the clarity of the high-definition terrain map.

[0082] Since the high-definition terrain map Figure 1 Generally, grassland, rock and other materials with high adaptation degree are selected for the map, which has a small size, but by adjusting the number of repeated tiling (referred to as tiling number or Tiling parameter), the map can be tiled like a ceramic tile to cover the entire terrain. However, in this process, due to the complete same map, too many tiling numbers can cause a grid-like repetition, affecting the presentation effect, and too few tiling numbers can cause blur due to transition stretching, also affecting the presentation effect. Therefore, setting a suitable tiling number parameter value will greatly affect the final presentation effect and ensure the clarity of the high-definition terrain map.

[0083] The factors affecting the tiling times include the height of the current aircraft from the ground and the side length of the terrain to be mapped, and the lower the height, the more the tiling times; the greater the side length of the terrain to be mapped, the more the tiling times.

[0084] The calculation formula of the repeated tiling parameter is as follows:

[0085]

[0086] wherein w is the side length of the terrain to be mapped, h is the height of the current aircraft from the ground, Tmin is the minimum tiling times, and Tmax is the maximum tiling times.

[0087] Referring to Figure 2 , the preprocessed high-definition terrain map specifically includes:

[0088] The side length w of the terrain to be mapped is obtained, and the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground is calculated.

[0089] The minimum tiling times Tmin and the maximum tiling times Tmax are determined according to the resolution of the high-definition terrain map.

[0090] The parameters of the high-definition terrain map are determined.

[0091] If the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground is less than the minimum tiling times Tmin, the parameters of the high-definition terrain map take the minimum tiling times Tmin.

[0092] If the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground is greater than the maximum tiling times Tmax, the parameters of the high-definition terrain map take the maximum tiling times Tmax.

[0093] If the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground is between the minimum tiling times Tmin and the maximum tiling times Tmax, the parameters of the high-definition terrain map take the ratio of the side length w of the terrain to be mapped to the height h of the current aircraft from the ground.

[0094] The parameters of the high-definition terrain map are determined, and the preprocessed high-definition terrain map is obtained.

[0095] The side length w of the terrain to be mapped is 1000 meters, the height h of the current aircraft from the ground is 20 meters, and the preset resolution of the high-definition terrain map is 1024*1024, at this time the minimum tiling times Tmin and the maximum tiling times Tmax are 10 times and 100 times respectively.

[0096] Since the ratio of the side length dimension w of the tiled terrain to the height h of the current aircraft from the ground is 50, 50 is selected as the Tiling parameter, and the preprocessed high-definition terrain map is obtained according to the determined Tiling parameter 50.

[0097] In implementation, the repeated tiling times are related to the side length dimension of the tiled terrain, the size of the high-definition terrain map and the area of the high-definition terrain map, and the repeated tiling times are determined to ensure that the high-definition terrain map has good resolution when applied to the terrain, so as to achieve the best visual effect.

[0098] 4) The satellite photo and the preprocessed high-definition terrain map of step 3) are mixed according to the mixing factor of step 2), the terrain map is completed, and the high-definition target terrain map is obtained.

[0099] The pixel point color value at any position on the satellite photo and the pixel point color value at any position on the preprocessed high-definition terrain map of step 3) are obtained according to the mixing factor T, respectively, and the final color value of the pixel point at any position on the terrain map is calculated; the above process is repeated to process all position pixel points, and the final color value of all pixel points is obtained, and the terrain map is completed.

[0100] The purpose of this step is to mix images, mainly using shader programming technology to mix the satellite photo and the preprocessed high-definition terrain map according to the calculated mixing factor, and output the final terrain map.

[0101] The shader is used to realize image rendering in computer graphics, replaces the traditional fixed rendering pipeline, and can be edited by using a shader programming language such as HLSL and GLSL. The VertexShader (vertex shader) is mainly responsible for the operation of the geometric relationship of the vertex, and the PixelShader (pixel shader) is mainly responsible for the calculation of the pixel color.

[0102] The mixed map operation in the application is performed in the pixel shader. In the pixel shader, the final color value of a single pixel point is operated, specifically, the color value at any position on the satellite photo and the color value at any position on the preprocessed high-definition terrain map are taken according to the mixing factor proportion to participate in the calculation, and after the operation, the final color value of the corresponding position on the terrain map is obtained. When the map processing of all position pixel points is completed, the terrain map is obtained.

[0103] The final color value C of a single position pixel point on the terrain map is calculated according to the following formula:

[0104] C=a(1-T)+b×T

[0105] Wherein: T is the mixing factor obtained in step 2), a is the color value of the corresponding pixel point on the satellite photo, and b is the color value of the corresponding pixel point on the preprocessed high-definition terrain map.

[0106] The application is described in detail with an actual application scenario as an example.

[0107] When the aircraft is parked on the ground, a satellite photo (see Figure 5 ), a high-definition terrain map (see Figure 6 ), and the height h of the current aircraft from the ground is 0 meters, the preset height threshold Ht is 100 meters, the mixing coefficient M is 0.7, the edge length size w of the terrain to be mapped is 1000 m, the resolution is 1024*1024, and the minimum tiling number Tmin and the maximum tiling number Tmax are 10 and 100, respectively.

[0108] According to the mixing factor calculation formula (2), the above data is substituted into the calculation to obtain a mixing factor T=0.7, and the parameters of the high-definition terrain map are 100 times, indicating that the final terrain map will be composed of 70% high-definition terrain map and 30% satellite photo map.

[0109] The clarity of the high-definition terrain map is adjusted according to the height h and the Tiling parameter, and then the image rendering is realized by the shader to complete the terrain map, see Figure 8 .

[0110] Figure 7 The high-definition terrain map is not mixed, and the satellite photo is directly mapped; by comparing Figure 7 and Figure 8 , the mixed terrain map method of the application not only retains the details of the satellite photo, but also greatly improves the clarity of the terrain map.

[0111] Embodiment 2

[0112] Referring to Figure 3 , a system for improving the clarity of terrain mapping in ground-based visual simulation, comprising:

[0113] A data acquisition module is configured to acquire a satellite photo, a high-definition terrain map, and the height h of the current aircraft from the ground.

[0114] A mixing factor generation module is configured to generate a mixing factor for the terrain map to be mixed according to the height h of the current aircraft from the ground.

[0115] An image preprocessing module is configured to adjust the parameters of the high-definition terrain map according to the height h of the current aircraft from the ground.

[0116] An image mixing module is configured to mix the acquired satellite photo and the preprocessed high-definition terrain map according to the mixing factor to obtain a high-definition target terrain map.

[0117] Referring to Figure 4 , the image preprocessing module comprises:

[0118] The data calculation module is configured to calculate the ratio of the terrain side length w to the current aircraft height h from the ground, and feed the calculation result to the data judgment module;

[0119] The data judgment module is configured to judge the ratio of the terrain side length w to the current aircraft height h from the ground according to the calculation result fed by the data calculation module, and feed the judgment result to the high-definition terrain map parameter selection module;

[0120] The high-definition terrain map parameter selection module is configured to select the parameters of the high-definition terrain map according to the judgment result fed by the data judgment module.

[0121] The above is the specific implementation of the present application, the above examples and the specific parameters in the examples are only for the purpose of clearly describing the verification process of the application, and are not intended to limit the patent protection scope of the present application, the patent protection scope of the present application is still subject to its claims, any equivalent structural changes made by using the contents of the specification and drawings of the present application shall also be included in the protection scope of the present application.

Claims

1. A method for improving the clarity of terrain maps in ground-hugging visual simulation, characterized in that, Includes the following steps: Acquire satellite images, high-resolution terrain maps, and the current altitude h of the aircraft above the ground; The blending factor T of the terrain texture to be blended is determined based on the current altitude h of the aircraft above the ground. The parameters of the high-definition terrain map are determined based on the height h, and a preprocessed high-definition terrain map is obtained; The satellite image and the preprocessed high-resolution terrain map are mixed based on the mixing factor T to obtain a high-resolution target terrain map; The blending factor T of the terrain texture to be blended is determined based on the current aircraft's altitude h above the ground, specifically including: Preset the height threshold Ht according to the actual application scenario; Set the mixing coefficient M based on the user's actual needs; The mixing factor T of the terrain texture to be mixed is determined based on the current aircraft's altitude h above the ground, the preset altitude threshold Ht, and the mixing coefficient M. The step of determining the parameters of the high-definition terrain map based on the height h and obtaining the preprocessed high-definition terrain map specifically includes: Obtain the side length w of the terrain to be mapped, and calculate the ratio of the side length w of the terrain to be mapped to the current height h of the aircraft above the ground; The minimum number of tiling operations, Tmin, and the maximum number of tiling operations, Tmax, are determined based on the preset resolution of the high-definition terrain map. Determine the parameters for the high-resolution terrain map: If the ratio of the side length w of the terrain to be mapped to the current height h of the aircraft above the ground is less than the minimum number of tiling times Tmin, then the parameters of the high-definition terrain map are taken as the minimum number of tiling times Tmin. If the ratio of the side length w of the terrain to be mapped to the current height h of the aircraft above the ground is greater than the maximum number of tiling times Tmax, then the parameters of the high-definition terrain texture map are taken as the maximum number of tiling times Tmax. If the ratio of the side length w of the terrain to be mapped to the current height h of the aircraft above the ground is between the minimum number of tiling times Tmin and the maximum number of tiling times Tmax, then the parameters of the high-definition terrain texture map are taken as the ratio of the side length w of the terrain to the current height h of the aircraft above the ground. Based on the determined parameters of the high-resolution terrain map, obtain a preprocessed high-resolution terrain map.

2. The method for improving terrain texture clarity in ground-hugging visual simulation according to claim 1, characterized in that, The determination of the current aircraft's altitude h above the ground is specifically as follows: A ray is emitted vertically downwards from the aircraft's location; When a ray collides with the terrain, the coordinates of the collision point can be obtained, and the collision point coordinates include the absolute height of the collision point. The current altitude h of the aircraft above the ground is obtained by subtracting the absolute altitude of the collision point from the absolute altitude of the aircraft.

3. The method for improving the clarity of terrain maps in ground-hugging visual simulation according to any one of claims 1-2, characterized in that, The mixing of the satellite imagery and the preprocessed high-resolution terrain map specifically includes: Pixels at arbitrary locations in the satellite image and pixels at arbitrary locations in the preprocessed high-resolution terrain map are selected respectively, and the locations are matched on the satellite image and the preprocessed high-resolution terrain map; The color values ​​of pixels at any position in the satellite image and the color values ​​of pixels at any position in the preprocessed high-definition terrain map are mixed according to the mixing factor T to obtain the final color value of the pixel at the corresponding position on the terrain to be mapped. Repeat the above steps until all pixels in the satellite image and all pixels in the preprocessed high-resolution terrain map have been traversed; Obtain the target terrain texture.

4. The method for improving terrain texture clarity in ground-hugging visual simulation according to claim 3, characterized in that, The specific steps for mixing the pixel color values ​​at any location in the satellite image and the pixel color values ​​at any location in the preprocessed high-resolution terrain map according to the mixing factor T to obtain the final pixel color value at the corresponding location on the terrain map are as follows: The final color value of a pixel at any position is calculated using the following formula: C = a(1-T) + b×T Where: T is the blending factor, a is the color value of the corresponding pixel in the satellite image, and b is the color value of the corresponding pixel in the high-resolution terrain map.

5. A system for improving the clarity of terrain maps in ground-hugging visual simulation, characterized in that, include: Data acquisition module: used to acquire satellite photos, high-resolution terrain maps, and the current altitude h of the aircraft above the ground; Blending Factor Generation Module: Used to generate blending factors for the terrain texture to be blended based on the obtained current aircraft height h above the ground; Image preprocessing module: used to adjust the parameters of the high-resolution terrain map according to the obtained current aircraft height h above the ground, and obtain the preprocessed high-resolution terrain map; Image blending module: Used to blend the acquired satellite images and the acquired preprocessed high-resolution terrain maps according to the generated blending factor to obtain a high-resolution target terrain map; The blending factor T of the terrain texture to be blended is determined based on the current aircraft's altitude h above the ground, specifically including: Preset the height threshold Ht according to the actual application scenario; Set the mixing coefficient M based on the user's actual needs; The mixing factor T of the terrain texture to be mixed is determined based on the current aircraft's altitude h above the ground, the preset altitude threshold Ht, and the mixing coefficient M. The image preprocessing module includes: Data calculation module: used to calculate the ratio of the terrain side length w to the current aircraft height h above the ground, and feed the calculation result back to the data judgment module; Data Judgment Module: This module determines the ratio of the terrain side length w to the current aircraft height h above the ground based on the calculation results fed back by the data calculation module, and compares the minimum and maximum number of tiling times. The judgment result is then fed back to the parameter selection module of the high-definition terrain map. High-resolution terrain map parameter selection module: Used to select parameters for high-resolution terrain maps based on the judgment results fed back by the data judgment module.

Images