CN117724850B - Field pre-travel path feasibility assessment method, system, equipment and medium - Google Patents

Abstract

The present application relates to a method, system, device and medium for assessing the feasibility of a field pre-pass path, which generates a road buffer by performing parallel calculation according to a preset road width; obtains corresponding DEM slice data based on the road vector data in the road buffer; projects and splices the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data; projects the road vector data into the coordinate system of the corresponding first DEM slice data, clips the first DEM slice data to obtain second DEM slice data; converts the second DEM slice data into a one-dimensional vector, calculates according to the slope percentage formula, and obtains the slope information corresponding to the pre-pass path; and assesses the feasibility of the pre-pass path through the slope information. The present invention realizes efficient processing and accurate analysis of geographic information.

Description

Field pre-travel path feasibility assessment method, system, equipment and medium

Technical Field

The present application relates to the field of geographic information technology, and in particular to a method, system, device and medium for assessing the feasibility of a field pre-travel path.

Background technique

At present, the demand for field pre-travel path feasibility assessment is increasing in the fields of road planning, environmental monitoring, and resource development. However, traditional path assessment methods often rely on manual surveys, map analysis, and expert experience, and have problems such as strong subjectivity, low efficiency, and inaccurate data. These problems limit the accuracy and efficiency of pre-travel path assessment, so a more efficient, accurate, and automated method is needed to meet the needs of the current field.

As a basic element for terrain feature analysis and visualization, slope reflects the degree of inclination of a point on the surface and is the first factor to be considered in path evaluation, road planning, and configuration of governance measures. Traditional slope calculation methods mostly use serial calculations, that is, calculating the slope value of pixel units one by one. However, when processing large-scale elevation data sets, this serial calculation method limits the calculation speed. In addition, in scenarios that require fast response or real-time performance, traditional serial calculation methods cannot meet the requirements. Especially in the context of modern computer hardware with multi-core and parallel computing capabilities, traditional serial calculation methods cannot fully utilize the hardware potential, resulting in computing tasks that become time-consuming and inefficient. Therefore, efficient calculation of large-scale elevation data is a technical problem that needs to be solved urgently.

Summary of the invention

Based on this, it is necessary to provide a field pre-travel path feasibility assessment method, system, equipment and medium that can efficiently process and accurately analyze geographic information to address the above technical problems.

A method for assessing the feasibility of a field pre-travel path, the method comprising:

Set the road width of the pre-passage path, and generate a road buffer zone through parallel calculation according to the preset road width;

Based on the road vector data in the road buffer, obtaining DEM slice data corresponding to the road vector data;

Projecting and splicing the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data;

Projecting the road vector data into the coordinate system of the corresponding first DEM slice data, and clipping the first DEM slice data based on the road vector data to obtain second DEM slice data;

The second DEM slice data is converted into a one-dimensional vector, and the one-dimensional vector is calculated according to a slope percentage formula to obtain slope information corresponding to the pre-travel path;

The feasibility of the pre-travel path is evaluated using the slope information.

In one embodiment, generating a road buffer zone through parallel calculation according to a preset road width includes:

Decomposing the pre-travel path into a number of road segments, and obtaining road vector data of each road segment;

The parallel loop instructions are used to traverse and process each road vector data at the same time, wherein for each road vector data, the geometric shape of the road buffer is generated according to the preset road width;

Merge all road buffer geometries into one collection to obtain a road buffer collection.

In one embodiment, based on the road vector data in the road buffer, obtaining DEM slice data corresponding to the road vector data includes:

Acquire vector data of each road in the road buffer set;

Extracting geometric information from each of the road vector data to obtain the latitude and longitude coordinate range of the minimum circumscribed rectangle of each road polygon;

According to the row number and strip mapping relationship of the DEM slice data corresponding to each longitude and latitude coordinate range, the row number and strip range of the DEM slice data corresponding to each road vector data are determined, and the DEM slice data corresponding to each road vector data is obtained.

In one embodiment, the DEM slice data is projected and spliced using multi-threaded parallel technology to obtain first DEM slice data, including:

Using multi-threading technology, a thread is assigned to each of the DEM slice data for projection processing, and the geographic coordinate system in each of the DEM slice data is converted into a projection coordinate system;

The order of the DEM slice data after conversion into the projection coordinate system is determined, and the DEM slice data are sequentially spliced to obtain the first DEM slice data of unified terrain.

In one embodiment, projecting the road vector data into the coordinate system of the corresponding first DEM slice data, clipping the first DEM slice data based on the road vector data to obtain the second DEM slice data, includes:

Projecting the road vector data into the projection coordinate system of the corresponding first DEM slice data, and then obtaining the projection coordinates of four vertices of the minimum circumscribed rectangle of each road polygon based on the road vector data;

The projection coordinate coverage range is converted into a pixel coordinate range, and then the corresponding first DEM slice data is clipped based on the pixel coordinate range to obtain second DEM slice data.

In one embodiment, the second DEM slice data is converted into a one-dimensional vector, and the one-dimensional vector is calculated according to a slope percentage formula to obtain the slope information corresponding to the pre-travel path, including:

Divide the second DEM slice data into a number of sub-areas, and obtain the elevation values of the center and surrounding pixels of each sub-area;

Based on the set vector length, the elevation values of the pixels at the same relative position in multiple sub-areas are combined to obtain an elevation value vector;

The elevation value vector is input into the NEON register, and the slope information corresponding to the pre-pass path is obtained by calculating the slope percentage formula.

In one embodiment, the feasibility of the pre-travel path is evaluated by using the slope information, including:

The slope information includes the slope percentage corresponding to the coordinates of each pixel point in the second DEM slice data;

Determine whether the slope percentage corresponding to each pixel point coordinate is greater than a threshold value, and mark the raster image pixels corresponding to each pixel point coordinate based on the determination result to generate a new raster image;

The new raster image is clipped according to the geometric shape of the preset road width to obtain a clipped raster image;

The cropped raster image is converted into vector data, and the feasibility of the pre-travel path is analyzed based on the vector data.

A field pre-travel path feasibility assessment system, the system comprising:

A buffer zone calculation module is used to set the road width of the pre-passing path and generate a road buffer zone through parallel calculation according to the preset road width;

A DEM slice data acquisition module, used for acquiring DEM slice data corresponding to the road vector data based on the road vector data in the road buffer;

A projection and splicing module, used for projecting and splicing the DEM slice data by using multi-thread parallel technology to obtain first DEM slice data;

A coordinate conversion and clipping module, used for projecting the road vector data into the coordinate system of the corresponding first DEM slice data, clipping the first DEM slice data based on the road vector data, and obtaining second DEM slice data;

A slope calculation module, used for converting the second DEM slice data into a one-dimensional vector, calculating the one-dimensional vector according to a slope percentage formula, and obtaining the slope information corresponding to the pre-travel path;

The evaluation and analysis module is used to evaluate the feasibility of the pre-travel path through the slope information.

A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of any one of the above methods when executing the computer program.

A computer-readable storage medium stores a computer program, which implements the steps of any of the above methods when executed by a processor.

The above-mentioned field pre-pass path feasibility assessment method, system, equipment and medium set the road width of the pre-pass path, and generate a road buffer through parallel calculation according to the preset road width; based on the road vector data in the road buffer, obtain the DEM slice data corresponding to the road vector data; use multi-threaded parallel technology to project and splice the DEM slice data to obtain the first DEM slice data; project the road vector data to the coordinate system of the corresponding first DEM slice data, and clip the first DEM slice data based on the road vector data to obtain the second DEM slice data; convert the second DEM slice data into a one-dimensional vector, calculate the one-dimensional vector according to the slope percentage formula, and obtain the slope information corresponding to the pre-pass path; and perform feasibility assessment on the pre-pass path through the slope information.

The present invention adopts multi-threaded parallel technology to project and splice DEM slice data to provide unified terrain data; by projecting road vector data into the coordinate system of the corresponding first DEM slice data, the first DEM slice data is clipped based on the road vector data to reduce data redundancy; the slope percentage calculation method is adopted to quantify the terrain slope information; the second DEM slice data is converted into a one-dimensional vector, and the slope calculation task is efficiently processed in units of vectors. The present invention adopts multi-threaded parallel technology to process multiple tasks simultaneously, and adopts NEON technology to perform the same type of operation on multiple data in the same instruction cycle, thereby overcoming the defect of low efficiency of the existing slope calculation method, greatly improving the calculation efficiency, and ensuring accurate and efficient evaluation of the traffic conditions of the newly planned path in the field.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a process flow of a method for assessing the feasibility of a field pre-travel path in one embodiment;

Figure 2 shows DEM elevation data in one embodiment. Schematic diagram of pixel sub-regions;

FIG3 is a schematic diagram of the structural framework of a field pre-travel path feasibility assessment system in one embodiment;

FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment.

Detailed ways

In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

It should be noted that in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating data of the indicated technical features. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

In the process of implementing the technology of this solution, the inventor found that the traditional path assessment method has problems such as strong subjectivity, low efficiency and inaccurate data. Based on this, the inventor proposed a field pre-pass path feasibility assessment method. By introducing OpenMP multi-threading technology, a computing task is decomposed into multiple subtasks, and each subtask is executed in parallel on different processor cores, which significantly improves the performance and computing efficiency of the program. In addition, the use of NEON technology to vectorize the slope percentage data fully utilizes the high-performance computing capabilities and realizes efficient processing and accurate analysis of geographic information.

The following will describe the implementation of the present invention in detail with reference to the accompanying drawings in the embodiment diagram of the present invention.

In one embodiment, as shown in FIG1 , a method for assessing the feasibility of a field pre-travel path is provided, comprising the following steps:

Step 202, setting the road width of the pre-travel path, and generating a road buffer zone through parallel calculation according to the preset road width.

It can be understood that for the roads to be opened, the road width is first set according to demand, and then a buffer area of a certain width is generated on both sides of the road according to the preset road width to ensure that space is reserved within a specific width range around the road.

Specifically, in order to improve the computing efficiency, parallel loop instructions are used to decompose the computing task into multiple parallel subtasks, and the line features are split into line segments, which are evenly distributed to each thread for buffer calculation.

Step 204: based on the road vector data in the road buffer, obtain DEM slice data corresponding to the road vector data.

It can be understood that road vector data usually contains an entire data set or layer of multiple road vector data, which is generally used to analyze, visualize and manage geospatial information. Road vector data refers to specific road elements in the map, such as the geometry, length, width, direction, topological relationship, etc. of the road, which can be used to represent a single road or road segment. DEM is a digital model used to represent the height of the ground surface, and DEM slice data divides this elevation information into multiple small areas or tiles to process and manage data more efficiently; each DEM slice data usually represents a specific geographic area, such as a specific latitude and longitude range or a specific terrain area. This slicing method enables users to accurately select and process the required geographic area without having to process the entire data set, thereby improving the operability and efficiency of the data.

Step 206: Project and splice the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data.

It can be understood that multithreading parallel technology is a technology that can execute multiple thread calculations at the same time. It uses the characteristics of multiple processing units (such as multi-core processors) in computer systems to process multiple tasks or subtasks at the same time. This parallel technology helps to improve the performance and efficiency of programs.

In this embodiment, the multi-thread parallel technology is used to decompose the entire processing process into multiple subtasks, each of which processes one or more DEM slice data, and then these subtasks are run simultaneously to improve the processing speed, especially in a multi-core processor or multi-thread environment, the efficiency of processing a large amount of DEM slice data can be significantly improved. By projecting the DEM slice data to convert them into the same coordinate system, the terrain data is unified so that the DEM slice data can be spliced into a large continuous data.

Step 208: Project the road vector data into the coordinate system of the corresponding first DEM slice data, and clip the first DEM slice data based on the road vector data to obtain second DEM slice data.

It can be understood that in order to increase the accuracy and consistency of the data, the road vector data is projected into the coordinate system of the corresponding first DEM slice data to ensure that the road vector data and the DEM slice data have the same spatial reference. At the same time, clipping the first DEM slice data based on the road vector data is more conducive to accurate spatial analysis for subsequent analysis.

On the other hand, clipping the first DEM slice data can narrow the processing scope, so that data analysis can focus more on the terrain of a specific area, reduce the amount of data and the processing scope, and improve the efficiency of subsequent processing.

In short, through projection alignment and clipping, we can better understand the characteristics of the terrain to be analyzed and improve the accuracy and efficiency of subsequent data analysis.

Step 210, converting the second DEM slice data into a one-dimensional vector, calculating the one-dimensional vector according to the slope percentage formula, and obtaining the slope information corresponding to the pre-travel path.

It can be understood that DEM slice data is a two-dimensional raster data, and its elevation information is stored in a matrix or array. Converting it into a one-dimensional vector can simplify slope calculation and facilitate the analysis and processing of elevation values. In addition, after converting DEM slice data into a one-dimensional vector, it is easier to determine the pixels around a specific location, which is convenient for neighborhood elevation analysis.

The percentage slope is a measure of the slope of a surface, calculated by measuring the ratio of vertical height to horizontal distance. Calculating the percentage slope provides important information about the surface to determine whether a road is passable.

Step 212: Perform feasibility assessment on the pre-travel path based on the slope information.

It can be understood that the slope information includes the slope percentage corresponding to the coordinates of all pixel points in the second DEM slice data. The steepness of the terrain corresponding to the pixel point is determined by comparing with the set threshold and marking it to determine whether the road is suitable for travel.

The above-mentioned field pre-pass path feasibility assessment method sets the road width of the pre-pass path, generates a road buffer through parallel calculation according to the preset road width; obtains DEM slice data corresponding to the road vector data based on the road vector data in the road buffer; projects and splices the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data; projects the road vector data into the coordinate system of the corresponding first DEM slice data, and clips the first DEM slice data based on the road vector data to obtain second DEM slice data; converts the second DEM slice data into a one-dimensional vector, calculates the one-dimensional vector according to the slope percentage formula, and obtains the slope information corresponding to the pre-pass path; and conducts feasibility assessment on the pre-pass path through the slope information.

The present invention adopts multi-threaded parallel technology to project and splice DEM slice data to provide unified terrain data; by projecting road vector data into the coordinate system of the corresponding first DEM slice data, the first DEM slice data is clipped based on the road vector data to reduce data redundancy; the slope percentage calculation method is adopted to quantify the terrain slope information; the second DEM slice data is converted into a one-dimensional vector, and the slope calculation task is efficiently processed in units of vectors. The present invention adopts multi-threaded parallel technology to process multiple tasks simultaneously, and adopts NEON technology to perform the same type of operation on multiple data in the same instruction cycle, thereby overcoming the defect of low efficiency of the existing slope calculation method, greatly improving the calculation efficiency, and ensuring accurate and efficient evaluation of the traffic conditions of the newly planned path in the field.

In one of the embodiments, a road buffer is generated through parallel calculation according to a preset road width, including: decomposing a pre-travel path into a number of road segments and obtaining road vector data of each road segment; using parallel loop instructions to traverse and process each road vector data at the same time, wherein for each road vector data, a geometric shape of the road buffer is generated according to the preset road width; and merging the geometric shapes of all road buffers into a set to obtain a road buffer set.

Specifically, first, the pre-pass path is decomposed into several road segments, and the road vector data of each road segment is obtained. The parallel loop instruction of OpenMP is used to decompose the computing task into multiple parallel subtasks. In the parallel loop, the number of threads is set to 8, and the line elements are split into segments, which are evenly distributed to each thread for buffer calculation. In addition, in order to ensure that only one thread can access the protected shared resources at the same time and avoid data competition and inconsistency, a mutex lock is created. It is worth noting that in the parallel loop, the number of threads can be designed according to the actual situation. The number of threads in this embodiment is set to 8 only for a clearer explanation and is not intended to be a limitation of the present invention.

Then, for each thread, assume that the two endpoints of the line segment are and/> , and the buffer radius of the road is w , the direction vector D of the line segment is calculated using the following formula:

;

;

According to the direction vector of the line segment and the radius of the buffer zone, the vertex of the new buffer zone polygon is obtained by vertically offsetting the point to calculate the buffer zone. In each iteration of the parallel loop, each subtask independently calculates the buffer zone geometry of the corresponding line segment. These calculation results will be stored in the corresponding data structure for subsequent processing and analysis.

Finally, the buffer calculation results for all lines are combined into a single set.

In one of the embodiments, based on the road vector data in the road buffer, DEM slice data corresponding to the road vector data is obtained, including: obtaining each road vector data in the road buffer set; extracting geometric information from each road vector data to obtain the longitude and latitude coordinate range of the minimum circumscribed rectangle of each road polygon; determining the row number and stripe range of the DEM slice data corresponding to each road vector data according to the mapping relationship between the row number and stripe of the DEM slice data corresponding to each longitude and latitude coordinate range, and obtaining the DEM slice data corresponding to each road vector data.

Specifically, the geometric information is extracted from the road vector data to obtain the latitude and longitude coordinate range of the minimum circumscribed rectangle of the road polygon. , where/> and/> Respectively represent the minimum longitude and latitude, and/> They represent the maximum longitude and latitude respectively. The above coordinate range defines the boundary of the road vector data in the geographic space and determines the geographic scope of the area where the road is located.

According to the mapping relationship between the row number and strip of the DEM slice data based on longitude and latitude, the row number and strip range of the DEM slice data corresponding to the road vector are determined.

Query and extract DEM slice data within this row number range and strip range. DEM slice data is usually stored in raster form, and each slice covers a local geographic area.

In one of the embodiments, multi-threaded parallel technology is used to project and splice DEM slice data to obtain first DEM slice data, including: using multi-threaded technology to assign a thread to each DEM slice data for projection processing, and converting the geographic coordinate system in each DEM slice data into a projection coordinate system; determining the order of each DEM slice data after conversion to the projection coordinate system, and splicing each DEM slice data in turn to obtain the first DEM slice data of unified terrain.

Specifically, a thread is started for each DEM slice data, and multi-threaded parallel technology is used to simultaneously perform projection operations on different DEM slice data, and the slice data is converted from the geographic coordinate system to the target projection coordinate system; each DEM slice data and its spatial position information, that is, the coordinate range in the projection coordinate system, is obtained, and is used to determine the order of slice splicing; the projected DEM data are spliced in sequence to ensure that they are closely connected in space.

In this embodiment, the DEM slice data is projected in parallel. A thread is assigned to each DEM slice data, and multi-thread parallel technology is used to simultaneously project different DEM slice data. Convert to UTM projection coordinates/> , to ensure accurate mapping of spatial locations.

In one of the embodiments, the road vector data is projected into the coordinate system of the corresponding first DEM slice data, and the first DEM slice data is clipped based on the road vector data to obtain the second DEM slice data, including: projecting the road vector data into the projection coordinate system of the corresponding first DEM slice data, and then obtaining the projection coordinates of the four vertices of the minimum circumscribed rectangle of each road polygon based on the road vector data; converting the projection coordinate coverage range into a pixel coordinate range, and then clipping the corresponding first DEM slice data based on the pixel coordinate range to obtain the second DEM slice data.

Specifically, the road vector data is projected into the same projection coordinate system as the DEM slice data.

Extract the projection coordinate range of the minimum enclosing rectangle from the polygon data in the road vector data .

Get the geographic transformation information of the DEM slice data, including the upper left corner coordinates, pixel width, /> Direction rotation angle, upper left corner /> Coordinates, /> Direction rotation angle and pixel height.

For each vertex in the projected vector data, use the geographic transformation information to convert its projection coordinates into pixel coordinates. The following formula is used for the conversion:

;

;

in, and/> is the projection coordinate, /> and/> is the pixel coordinate, /> Represents the upper left corner of the DEM slice data/> Coordinates, /> Represents the upper left corner of the DEM slice data/> Coordinates, /> is the pixel width, /> is the pixel height.

Use the converted pixel coordinate range to locate the corresponding rectangular area in the DEM slice data, and then cut out the part containing the area in the DEM slice data.

In one of the embodiments, the second DEM slice data is converted into a one-dimensional vector, and the one-dimensional vector is calculated according to the slope percentage formula to obtain the slope information corresponding to the pre-pass path, including: dividing the second DEM slice data into a plurality of sub-areas, and obtaining the elevation values of the center and surrounding pixels of each sub-area; based on a set vector length, combining the elevation values of pixels with the same relative position in a plurality of sub-areas to obtain an elevation value vector; inputting the elevation value vector into a NEON register, and calculating according to the slope percentage formula to obtain the slope information corresponding to the pre-pass path.

Specifically, the NEON technology is used to convert the two-dimensional image of the second DEM slice data into a one-dimensional vector, and the slope calculation task is efficiently processed using vectors as units.

As shown in Figure 2, the DEM slice data is obtained The elevation value of the central pixel of the sub-region and the elevation values of the surrounding 8 pixels; input the pixel elevation value vector into the NEON register and calculate according to the slope percentage formula/> The slope percentage of the central pixel of the sub-region. The slope percentage formula is:

;

;

;

in is the slope percentage, /> is the horizontal increment, /> is the elevation increment, /> For/> The elevation value of each pixel in the sub-area, /> For/> The spatial resolution of the pixel in the direction, /> For/> The spatial resolution of pixels in the direction;

It can be understood that by setting the vector length , define 8 pixel elevation value vectors respectively, that is, each vector Stored /> Continuous/> In the sub-area/> The elevation value of. Among them, /> is the ratio of the number of bits in the vector register to the length of the variable type. Taking the specific parameters as an example, if the number of bits in the vector register is 128 bits and the variable type is float32, then the vector length is 4. Therefore, every 4/> The height values of pixels with the same relative position in the window will be combined into a vector. More specifically, a vector with a length of 4 is defined. , used to store 4 consecutive /> The pixel elevation value of the upper left corner of the window center; define a vector with a length of 4/> , used to store 4 consecutive /> The elevation value of the pixel directly above the center of the window, and so on.

Design a NEON Intrinsics program to efficiently parallelize the slope percentage calculation of multiple sets of data. The specific steps are as follows: Input the pixel elevation value vector into the NEON register; Use the NEON Intrinsics instruction to calculate the vector corresponding to the horizontal increment according to the slope percentage calculation formula And the vector corresponding to the vertical increment ; By passing the vector /> Divide by vector/> And multiply by 100 to get the resulting vector /> .

For redundant data whose number is less than s in a group, they are processed separately in sequence. For example, the above steps are repeated until the number of remaining pixels is less than 4, and for redundant data whose number is less than 4, they are processed separately in sequence.

Finally, the results of parallel calculation using the NEON intrinsics program are combined with the results of separate calculations to form the final result, and the slope information corresponding to the pre-pass path is obtained.

In this embodiment, based on the Single Instruction Multiple Data (SIMD) extension instruction of the FT2500+ processor, 32 128-bit vector registers are used to simultaneously process multiple data elements in a single instruction, thereby improving the efficiency of intensive data calculations.

In one of the embodiments, the feasibility of the pre-travel path is evaluated through slope information, including: the slope information includes the slope percentage corresponding to the coordinates of each pixel point in the second DEM slice data; judging whether the slope percentage corresponding to the coordinates of each pixel point is greater than a threshold, marking the raster image pixels corresponding to the coordinates of each pixel point based on the judgment result to generate a new raster image; cropping the new raster image according to the geometric shape of a preset road width to obtain a cropped raster image; converting the cropped raster image into vector data, and analyzing the feasibility of the pre-travel path based on the vector data.

Specifically, the slope percentage corresponding to each pixel point in the slope information is obtained one by one.

Setting Thresholds , threshold /> Approximately equal to the friction coefficient between car tires and roads/> . Determine in turn whether the slope value of each pixel point is greater than a preset threshold value/> , if the slope percentage is greater than/> , indicating that the terrain at the pixel point is steep and not suitable for travel, the raster image pixel corresponding to the pixel point coordinate is set to 0. If the slope percentage is less than or equal to/> , indicating that the terrain at the pixel point is relatively flat and suitable for travel, and the raster image pixel corresponding to the pixel point coordinate is set to 1.

Generates a new raster image from the marked raster image at the specified raster resolution, where each pixel corresponds to a pass mark 0 or 1.

The raster image is clipped according to the geometric shape of the preset road width, the pixel value in the non-road range is set to -1, and the pixel values in other areas will remain unchanged. The clipped raster image is converted into vector data, and the feasibility of the pre-travel path is analyzed based on the vector data.

Specifically, for each pixel coordinate , get the corresponding slope percentage/> .

For each pixel , determine whether the slope value is greater than a preset threshold value/> .if , indicating that the terrain is steep and not suitable for travel, the raster image pixel corresponding to the pixel coordinate is set to 0; if /> , indicating that the terrain is relatively flat and suitable for travel, and the raster image pixel corresponding to the pixel coordinate is set to 1.

By specifying the grid resolution , generate a new raster image/> , where/> and/> Represents the row and column indices of a raster image, with each raster pixel representing a pass flag of 0 or 1.

Clip raster images to the geometry of a preset road width , set the pixels in the non-road range to -1, and the pixel values in other areas will remain unchanged. Convert the clipped raster data into vector data. The evaluation accuracy of this method is affected by the resolution of DEM slice data. Using high-resolution DEM slice data can improve the path feasibility evaluation effect.

It can be understood that in the buffer calculation and projection stage, the present invention uses multi-threaded parallel technology to perform projection operations on DEM slice data, effectively improving the efficiency and real-time performance of data processing, making full use of system resources, and also enhancing the scalability of the system. In the slope calculation process, the NEON vector acceleration model is used to simultaneously process multiple data points in a single instruction cycle, giving full play to the hardware performance, greatly enhancing the calculation efficiency, and providing an efficient and feasible solution for geographic data processing. These innovative strategies make the present invention have obvious advantages in processing large-scale elevation data and road slope calculation, and provide strong support for the optimization and application of geographic information systems.

It should be understood that, although the various steps in the flowchart of FIG. 1 are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in FIG. 1 may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

In one embodiment, as shown in FIG3 , a field pre-travel path feasibility assessment system is provided, including: a buffer calculation module 402, a DEM slice data acquisition module 404, a projection splicing module 406, a coordinate conversion and clipping module 408, a slope calculation module 410 and an assessment analysis module 412, wherein:

The buffer zone calculation module 402 is used to set the road width of the pre-travel path and generate a road buffer zone through parallel calculation according to the preset road width.

The DEM slice data acquisition module 404 is used to acquire DEM slice data corresponding to the road vector data based on the road vector data in the road buffer.

The projection and splicing module 406 is used to project and splice the DEM slice data using multi-thread parallel technology to obtain first DEM slice data.

The coordinate conversion and clipping module 408 is used to project the road vector data into the coordinate system of the corresponding first DEM slice data, and clip the first DEM slice data based on the road vector data to obtain second DEM slice data.

The slope calculation module 410 is used to convert the second DEM slice data into a one-dimensional vector, calculate the one-dimensional vector according to the slope percentage formula, and obtain the slope information corresponding to the pre-travel path.

The evaluation and analysis module 412 is used to evaluate the feasibility of the pre-travel path based on the slope information.

In one embodiment, the DEM slice data acquisition module 404 includes:

The boundary generation unit is used to extract geometric information from the road vector data to obtain the latitude and longitude coordinate range of the minimum circumscribed rectangle of each road polygon.

The DEM positioning unit is used to determine the row number and strip range of the DEM slice data corresponding to each road vector data according to the row number and strip mapping relationship of the DEM slice data corresponding to each latitude and longitude coordinate range, and obtain the DEM slice data corresponding to each road vector data.

In one embodiment, the projection stitching module 406 includes:

The parallel projection unit, by adopting multi-threading technology, allocates a thread to each DEM slice data for projection processing, and converts the geographic coordinate system in each DEM slice data into a projection coordinate system.

The splicing unit is used to determine the order of each DEM slice data after conversion into the projection coordinate system, and to splice each DEM slice data in turn to obtain the first DEM slice data of unified terrain.

In one embodiment, the coordinate conversion and clipping module 408 includes:

The coordinate conversion unit is used to convert the projection coordinate coverage of the minimum circumscribed rectangle of each road polygon into a pixel coordinate range.

The clipping unit is used to clip the corresponding first DEM slice data according to the converted pixel coordinate range to obtain second DEM slice data.

In one embodiment, the slope calculation module 410 includes:

Define a unit for obtaining the elevation values of the center and surrounding pixels of each sub-area from the second DEM slice data and define a slope percentage calculation formula.

The vector acceleration unit combines the elevation values of pixels with the same relative position in multiple sub-areas based on the set vector length to obtain an elevation value vector, and then inputs the elevation value vector into the NEON register. At the same time, it calculates the slope percentage of multiple groups of data to obtain the slope information corresponding to the pre-pass path.

In one embodiment, the evaluation and analysis module 412 includes:

The slope analysis unit is used to determine whether the slope value of each pixel point is greater than a preset threshold. If it is greater than the threshold, the pixel at the corresponding position is set to 0; if it is less than or equal to the threshold, the pixel at the corresponding position is set to 1.

Vector conversion unit, which clips raster images and converts them into vector data by using geometric shapes of preset road widths.

For the specific limitations of the field pre-pass path feasibility assessment system, please refer to the limitations of the field pre-pass path feasibility assessment method above, which will not be repeated here. Each module in the above-mentioned field pre-pass path feasibility assessment system can be implemented in whole or in part through software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as shown in FIG4. The computer device includes a processor, a memory, a network interface, and a database connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store field pre-pass path feasibility assessment data. The network interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, a field pre-pass path feasibility assessment method is implemented.

Those skilled in the art will understand that the structure shown in FIG. 4 is merely a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

Step 202, setting the road width of the pre-travel path, and generating a road buffer zone through parallel calculation according to the preset road width.

Step 204: based on the road vector data in the road buffer, obtain DEM slice data corresponding to the road vector data.

Step 206: Project and splice the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data.

Step 208: Project the road vector data into the coordinate system of the corresponding first DEM slice data, and clip the first DEM slice data based on the road vector data to obtain second DEM slice data.

Step 210, converting the second DEM slice data into a one-dimensional vector, calculating the one-dimensional vector according to the slope percentage formula, and obtaining the slope information corresponding to the pre-travel path.

Step 212: Perform feasibility assessment on the pre-travel path based on the slope information.

In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

Step 202, setting the road width of the pre-travel path, and generating a road buffer zone through parallel calculation according to the preset road width.

Step 204: based on the road vector data in the road buffer, obtain DEM slice data corresponding to the road vector data.

Step 206: Project and splice the DEM slice data using multi-threaded parallel technology to obtain first DEM slice data.

Step 208: Project the road vector data into the coordinate system of the corresponding first DEM slice data, and clip the first DEM slice data based on the road vector data to obtain second DEM slice data.

Step 210, converting the second DEM slice data into a one-dimensional vector, calculating the one-dimensional vector according to the slope percentage formula, and obtaining the slope information corresponding to the pre-travel path.

Step 212: Perform feasibility assessment on the pre-travel path based on the slope information.

A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and/or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present invention. It should be noted that, for a person of ordinary skill in the art, several modifications and improvements may be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims (9)

1. A method for evaluating feasibility of a pre-traffic path in the field, the method comprising:

setting the road width of a pre-passing path, and generating a road buffer area through parallel calculation according to the preset road width;

obtaining DEM slice data corresponding to the road vector data based on the road vector data in the road buffer area;

projecting and splicing the DEM slice data by adopting a multithreading parallel technology to obtain first DEM slice data;

Projecting the road vector data into a coordinate system of the corresponding first DEM slice data, and cutting the first DEM slice data based on the road vector data to obtain second DEM slice data;

converting the second DEM slice data into a one-dimensional vector, and calculating the one-dimensional vector according to a gradient percentage formula to obtain gradient information corresponding to a pre-passing path;

Carrying out feasibility assessment on the pre-passing path through the gradient information;

Converting the second DEM slice data into a one-dimensional vector, calculating the one-dimensional vector according to a gradient percentage formula to obtain gradient information corresponding to a pre-passing path, wherein the method comprises the following steps of:

Dividing the second DEM slice data into a plurality of subareas, and obtaining the elevation values of the central and peripheral pixel points of each subarea;

combining the elevation values of the pixel points with the same relative positions in a plurality of different subareas based on the set vector length to obtain an elevation value vector;

And inputting the elevation value vector into a NEON register, and simultaneously calculating gradient percentages of a plurality of groups of data through the gradient percentage formula to obtain gradient information corresponding to the pre-passing path.

2. The method for evaluating feasibility of a field pre-passing path according to claim 1, wherein generating a road buffer by parallel calculation according to a preset road width comprises:

decomposing the pre-passing path into a plurality of road segments to obtain road vector data of each road segment;

Traversing and processing the road vector data simultaneously by adopting a parallel circulation instruction, wherein the geometric shape of a road buffer area is generated for each road vector data according to a preset road width;

And merging the geometric shapes of all the road buffers into one set to obtain a road buffer set.

3. The method of assessing feasibility of a field pre-transit path of claim 2, wherein obtaining DEM slice data corresponding to road vector data in the road buffer based on the road vector data, comprises:

acquiring each road vector data in the road buffer area set;

Extracting geometric information from each road vector data to obtain the longitude and latitude coordinate range of the minimum circumscribed rectangle of each road polygon;

And determining the line number and the stripe range of the DEM slice data corresponding to each road vector data according to the line number and the stripe mapping relation of the DEM slice data corresponding to each longitude and latitude coordinate range, and obtaining the DEM slice data corresponding to each road vector data.

4. The method for evaluating feasibility of a field pre-transit path according to claim 3, wherein projecting and splicing the DEM slice data by using a multi-thread parallel technique to obtain first DEM slice data comprises:

Adopting a multithreading technology, respectively distributing a thread for each DEM slice data to carry out projection processing, and converting a geographic coordinate system in each DEM slice data into a projection coordinate system;

determining the sequence of the DEM slice data converted into a projection coordinate system, and sequentially splicing the DEM slice data to obtain first DEM slice data of uniform topography.

5. The method of claim 4, wherein projecting the road vector data into a coordinate system of the corresponding first DEM slice data, clipping the first DEM slice data based on the road vector data to obtain second DEM slice data, includes:

projecting the road vector data into a corresponding projection coordinate system of the first DEM slice data, and then acquiring projection coordinates of four vertexes of the minimum circumscribed rectangle of each road polygon based on the road vector data;

and converting the projection coordinate coverage into a pixel coordinate range, and then cutting the corresponding first DEM slice data based on the pixel coordinate range to obtain second DEM slice data.

6. The field pre-passage path feasibility assessment method according to any one of claims 1 to 5, characterized in that the feasibility assessment of the pre-passage path by the gradient information comprises:

The gradient information comprises gradient percentages corresponding to coordinates of each pixel point in the second DEM slice data;

judging whether the gradient percentage corresponding to each pixel point coordinate is larger than a threshold value, and marking the raster image pixel corresponding to each pixel point coordinate based on a judging result so as to generate a new raster image;

Cutting the new raster image according to the geometric shape of the preset road width to obtain a cut raster image;

And converting the cut raster image into vector data, and analyzing the feasibility of the pre-passing path based on the vector data.

7. A field pre-transit path feasibility assessment system, the system comprising:

the buffer zone calculation module is used for setting the road width of the pre-passing path and generating a road buffer zone through parallel calculation according to the preset road width;

the DEM slice data acquisition module is used for acquiring DEM slice data corresponding to the road vector data based on the road vector data in the road buffer area;

the projection splicing module is used for projecting and splicing the DEM slice data by adopting a multithreading parallel technology to obtain first DEM slice data;

the coordinate conversion and clipping module is used for projecting the road vector data into a coordinate system of the corresponding first DEM slice data, clipping the first DEM slice data based on the road vector data, and obtaining second DEM slice data;

The gradient calculation module is used for converting the second DEM slice data into a one-dimensional vector, and calculating the one-dimensional vector according to a gradient percentage formula to obtain gradient information corresponding to the pre-passing path;

the evaluation analysis module is used for carrying out feasibility evaluation on the pre-passing path through the gradient information;

Wherein, the slope calculation module includes:

The definition unit is used for acquiring the elevation values of the central and peripheral pixel points of each sub-region from the second DEM slice data and defining a gradient percentage calculation formula;

And the vector acceleration unit is used for combining elevation values of pixel points with the same relative positions in a plurality of subareas based on the set vector length to obtain an elevation value vector, inputting the elevation value vector into the NEON register, and simultaneously calculating gradient percentages of a plurality of groups of data to obtain gradient information corresponding to the pre-passing path.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any of claims 1 to 6 when the computer program is executed.

9. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 6.