A multi-line cross-precision DEM data fusion method, system, device, medium and product

Abstract

The application discloses a multi-line cross-precision DEM data fusion method, system, device, medium and product, relates to the field of geographic information science and technology, and constructs a low-precision tile library based on low-precision background DEM data; constructs a high-precision tile library based on gallery-type high-precision DEM data; constructs a fusion tile library by feathering and fusing line tiles and background tiles; generates new tiles covering lines from newly-added gallery-type high-precision DEM slices, stores the new tiles into the high-precision tile library, effectively guarantees the continuity of DEM data, and makes the regional DEM data truly reflect actual landform features; feathers and fuses the new tiles and the background tiles, updates the fusion tile library, and improves the updating efficiency of gallery-type DEM data; and based on low-level tile requests and high-level tile requests, corresponding tile data is output from the low-precision tile library and the updated fusion tile library, and cross-precision fused DEM data is obtained.

Description

Technical Field

[0001] This application relates to the fields of geographic information science and technology, and in particular to a method, system, device, medium and product for multi-line cross-precision DEM data fusion. Background Technology

[0002] A Digital Elevation Model (DEM) is a digital model reflecting the spatial distribution of Earth's surface elevation. Slicing DEMs, constructing pyramids, and publishing services are currently the core methods for providing 3D terrain services. While most DEMs reflect large-scale, continuously covered surface undulations, corridor-type data, such as power transmission lines and elevated railways, are typically collected along the corridor using aerial or LiDAR (Light Detection and Ranging) systems. The resulting DEM is not a uniform grid covering the entire area, but rather a narrow strip-shaped DEM focusing on the high-precision undulations along the corridor path. The data accuracy along the longitudinal direction is significantly higher than that of other areas. In practical applications, fusing this type of high-precision corridor-type DEM data with low-precision, large-scale background DEM data primarily focuses on smoothly eliminating abrupt changes in the accuracy between the two types of data.

[0003] The current conventional method defines a high-precision core area based on the corridor's centerline, sets up a ring-shaped transition zone around it, and uses a pixel-by-pixel feathering fusion approach to preserve the high precision of the corridor's internal terrain and eliminate abrupt changes in the external background DEM, achieving seamless visual and geometric stitching. However, this approach can lead to weight conflicts and data logic confusion when multiple lines intersect, resulting in terrain discrepancies at intersections, disrupting the continuity of the DEM, and preventing the DEM in that area from accurately reflecting the actual landform features. Furthermore, the current conventional method requires fusion processing of all data before pyramid tile construction and service publishing, which reduces the update efficiency of frequently updated corridor-type DEM data.

[0004] It is evident that existing conventional technologies cannot accurately reflect actual landform features after fusing high-precision corridor DEM data with low-precision background DEM data over a large area, and this can easily lead to a decrease in the efficiency of corridor DEM data updates. Summary of the Invention

[0005] The purpose of this application is to provide a method, system, device, medium and product for fusing multi-line cross-precision DEM data, so as to solve the problems that fused DEM data cannot truly reflect the actual landform features and the low update efficiency of corridor-type DEM data.

[0006] To achieve the above objectives, this application provides the following solution: Firstly, this application provides a method for fusing multi-line, cross-precision DEM data, including: Low-precision background DEM data is sliced ​​to generate background tiles covering the entire area, and the background tiles are then used to generate a background pyramid corresponding to their respective levels. Based on the background tiles and background pyramid, a low-precision tile library is constructed. High-precision DEM data of corridor type is sliced ​​to generate line tiles covering the perimeter of the line. Based on the line tiles and their corresponding grades, a high-precision tile library is constructed. Based on the line tiles and background tiles, a fused tile library is constructed through transparency judgment, feathering fusion processing, and sampling processing; The newly added corridor-type high-precision DEM data slices are used to generate new tiles covering the perimeter of the line, and stored in the high-precision tile library. The newly added tile is feathered and merged with the background tile, and the newly merged tile and the pyramid corresponding to the newly merged tile are stored in the merged tile library to obtain the updated merged tile library; Based on low-level tile requests and high-level tile requests, corresponding tile data are output from the low-precision tile library and the updated fused tile library to obtain cross-precision fused DEM data.

[0007] Secondly, this application provides a multi-line, cross-precision DEM data fusion system, comprising: The low-precision data processing module is used to slice low-precision background DEM data to generate background tiles covering the entire area, and generate a background pyramid corresponding to the level of the background tiles; and to construct a low-precision tile library based on the background tiles and the background pyramid. A high-precision data processing module is used to generate line tiles covering the perimeter of the line from corridor-type high-precision DEM data slices; and to construct a high-precision tile library based on the line tiles and their corresponding grades. The high- and low-precision data fusion module is used to construct a fused tile library based on the line tiles and background tiles through transparency judgment, feathering fusion processing and sampling processing; A new fusion update module is added to generate new tiles covering the perimeter of the newly added corridor-type high-precision DEM data slices and store them in the high-precision tile library; the new tiles are feathered and fused with the background tiles, and the newly fused tiles and the corresponding pyramids are stored in the fusion tile library to obtain the updated fusion tile library; The data publishing module is used to output corresponding tile data from the low-precision tile library and the updated fused tile library based on low-level tile requests and high-level tile requests, so as to obtain cross-precision fused DEM data.

[0008] Thirdly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the multi-line cross-precision DEM data fusion method described in any one of the above.

[0009] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the multi-line cross-precision DEM data fusion method described above.

[0010] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the multi-line cross-precision DEM data fusion method described above.

[0011] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides a method, system, device, medium, and product for multi-line cross-precision DEM data fusion. It constructs a low-precision tile library based on background tiles generated from low-precision background DEM data slices and their corresponding level pyramids; it constructs a high-precision tile library based on line tiles generated from corridor-type high-precision DEM data slices and their corresponding levels; it feathers and fuses the line tiles and background tiles to construct a fused tile library; it generates new tiles covering the perimeter of newly added corridor-type high-precision DEM slices and stores them in the high-precision tile library, avoiding terrain overlap issues at line intersections and effectively ensuring the continuity of DEM data, making the DEM data in this area truly reflect the actual landform features; it feathers and fuses the new tiles with background tiles to update the fused tile library, improving the update efficiency of corridor-type DEM data; based on low-level and high-level tile requests, it outputs corresponding tile data from the low-precision tile library and the updated fused tile library to obtain cross-precision fused DEM data. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1A schematic flowchart of a multi-line cross-precision DEM data fusion method provided in an embodiment of this application; Figure 2 This is a schematic diagram of low-precision DEM data provided in an embodiment of this application; Figure 3 This is a schematic diagram of a corridor-type high-precision DEM data provided in an embodiment of this application; Figure 4 This is an example diagram illustrating a step-like abrupt change at the junction of high and low precision data when the embodiments of this application are not implemented. Figure 5 This is an example diagram illustrating the effect of high- and low-precision data fusion provided in an embodiment of this application. Figure 6 A schematic diagram of a multi-line cross-precision DEM data fusion system provided in an embodiment of this application; Figure 7 A schematic diagram of the DEM data fusion structure of multiple high-voltage transmission lines provided in an embodiment of this application; Figure 8 This is a schematic diagram of the internal structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0014] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0015] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] This application provides a method and system for layered fusion of corridor-type multi-line cross-precision DEM data. By establishing three types of tile libraries, formulating tile slicing and publishing strategies with different precision, and supporting multiple data appending strategies, it ensures lossless high precision at the intersection of multiple lines while avoiding repeated operations on existing unchanged data during data updates. It is suitable for application scenarios that require simultaneous publishing of corridor-type multi-line high-precision DEM and low-precision background DEM.

[0017] In one exemplary embodiment, such as Figure 1 As shown, a method for fusing multi-line cross-precision DEM data is provided. This method is executed by computer equipment, specifically by a terminal or server alone, or by both a terminal and a server. The method includes the following steps.

[0018] S1: Slice the low-precision background DEM data to generate background tiles covering the entire area, and generate a background pyramid corresponding to the level of the background tiles.

[0019] S2: Based on the background tiles and background pyramid, construct a low-precision tile library.

[0020] S3: Slice the high-precision DEM data of the corridor type to generate line tiles covering the perimeter of the line, and construct a high-precision tile library based on the line tiles and their corresponding grades.

[0021] S4: Based on the line tiles and background tiles, construct a fused tile library through transparency judgment, feathering fusion processing and sampling processing.

[0022] S5: The newly added corridor-type high-precision DEM data slices are used to generate new tiles covering the perimeter of the line, and stored in the high-precision tile library.

[0023] S6: Feather the newly added tile and the background tile, and store the newly added and merged tile and the pyramid corresponding to the newly added and merged tile in the merged tile library to obtain the updated merged tile library.

[0024] S7: Based on low-level tile requests and high-level tile requests, output the corresponding tile data from the low-precision tile library and the updated fused tile library to obtain cross-precision fused DEM data.

[0025] In one exemplary embodiment, a low-precision tile library, a high-precision tile library, and a fused tile library are constructed respectively to address the data situation and the needs for subsequent data appending, updating, and service publishing.

[0026] As one feasible implementation method, low-precision background DEM data is sliced ​​to generate background terrain tiles covering the entire area, and corresponding pyramid levels N to M are constructed. Based on the background tiles and their corresponding pyramid levels, a low-precision tile library is constructed. The low-precision DEM data in the low-precision tile library covers the tile data of pyramid levels N to M (N≥1, M>N), where level N represents the low-precision level corresponding to the background tile and level M represents the high-precision level corresponding to the background tile.

[0027] After slicing the first high-precision DEM data of the corridor, terrain tiles covering the area around the line are generated, corresponding to the highest precision level P. A high-precision tile library is then constructed based on the line tiles and their corresponding levels.

[0028] The high-precision DEM data in the high-precision tile library has only one layer, P-level (P>>M). Tiles at this level are not used to construct a pyramid or for data publishing; they are only used to provide raw data tiles for subsequent high- and low-precision data fusion. Meanwhile, the high-precision M-level background tile data in the low-precision tile library is used for subsequent fusion processing with the high-precision tile data, and also, through upsampling, is used together with other N- to M-1 level background tile data as subsequent data for direct service publishing.

[0029] The tile formed by merging the background tiles generated from low-precision data slices and the line tiles generated from high-precision data slices at their junctions is simply referred to as a "merged tile." The merged tile library is mainly used to store the tile data and pyramid data after feathering and merging high- and low-precision DEM data, which can then be directly published as a service. For example, it can cover tile data from pyramid levels M+1 to P.

[0030] In an exemplary embodiment, S4 constructs a fused tile library based on the line tiles and background tiles through transparency judgment, feathering fusion processing, and sampling processing, specifically including: S401: Mark all line tiles in the high-precision tile library as need_blend=1; where need_blend represents the tiles to be merged, and the tiles to be merged refer to all data after the first high-precision DEM data slice, that is, the area covered by the first power line.

[0031] S402: Traverse the tiles to be merged in the high-precision tile library and determine the transparency of the tiles to be merged.

[0032] A: If the tile to be merged is completely opaque, then the area covered by the first line tile is determined to be high-precision DEM data. The first line tile is marked as needs_blend=0 and directly stored in the merged tile library.

[0033] B: If the tile to be fused is completely transparent, then the area covered by the second line tile is determined to be not entirely high-precision DEM data; the background tile is upsampled and processed with the second line tile to obtain a first fused tile of level P, and the first fused tile is downsampled to obtain a second fused tile of level M+1 to P-1, and the first fused tile and the second fused tile are stored in the fused tile library.

[0034] S403: Upsample the background tiles of level M in the low-precision tile library corresponding to the coverage area of ​​the second line tile to the background tiles of level M+1 to level P, perform edge feathering and fusion of the background tiles of level P with the second line tile to eliminate the seams, obtain the first fused tile of level P, mark it as need_blend=0, and store it in the fused tile library.

[0035] S404: Mark the background tiles upsampled to levels M+1 to P-1 as need_update=1, indicating tiles to be updated; merge and downsample the first fused tiles of level P in the fused tile library to generate second fused tiles of levels M+1 to P-1, replace the background tiles of levels M+1 to P-1 with need_update=1, mark them as need_update=0, and store them in the fused tile library, which stores the second fused tiles of levels M+1 to P-1, the first fused tiles of level P, and the first line tiles of level P.

[0036] In an exemplary embodiment, S5 generates new tiles covering the perimeter of the line from the newly added corridor-type high-precision DEM data slices and stores them in the high-precision tile library, specifically including: S501: Generate new tiles covering the perimeter of the newly added corridor-type high-precision DEM data slices and return them to the current high-precision tile library.

[0037] S502: Determine the transparency of the existing line tiles at the location of the new tile.

[0038] A: If the original line tile at the corresponding location is completely opaque, that is, if the newly added tile completely overlaps with the high-precision DEM data in the high-precision tile library (such as the center of the intersection of two lines), then the newly added tile will directly cover the original line tile, be marked as need_blend=1, and stored in the high-precision tile library.

[0039] B: If the original line tile at the corresponding location is partially transparent, that is, the newly added tile partially overlaps with the high-precision DEM data in the high-precision tile library, then the newly added tile will be merged with the original line tile (DstOver operation), marked as need_blend=1, and stored in the high-precision tile library.

[0040] C: If the existing line tile at the corresponding location is completely transparent, that is, the newly added tile does not overlap with the high-precision DEM data in the high-precision tile library, then the newly added tile will be directly marked as needs_blend=1 and stored in the high-precision tile library.

[0041] After the above operations, the current "high-precision tile library" stores P-level line tiles corresponding to two corridor-type high-precision DEM data.

[0042] In one exemplary embodiment, incremental feathering fusion is performed on the line tiles corresponding to the newly added corridor-type high-precision DEM data and the background tiles corresponding to the low-precision DEM data.

[0043] Repeat steps S401-S404 to update the newly added merged tiles and their corresponding pyramids to the merged tile library.

[0044] At this point, the low-precision tile library stores background tiles from level N to level M, and the fused tile library stores fused tiles from level M+1 to level P.

[0045] In an exemplary embodiment, S7 outputs corresponding tile data from the low-precision tile library and the updated fused tile library based on low-level tile requests and high-level tile requests, to obtain cross-precision fused DEM data, specifically including: Configure both low-precision tile libraries and fused tile libraries as tile data sources, and send the required tile requests, including the spatial range and precision level of the data.

[0046] For low-level tile requests, return the corresponding background tile from the N-level to M-level pyramids in the current low-precision tile library.

[0047] For high-level tile requests, calculate whether there is tile data in the M+1 to P level pyramid of the fused tile library within the calculated data coverage range: If so, return the pyramid tiles from level M+1 to level P in the fusion tile library.

[0048] If not, it indicates that there is no high-precision DEM data in this area, and the response will be based on the corresponding M-level background tiles in the low-precision tile library: If the request is for M-level data, the background tile corresponding to the low-precision tile library will be returned directly.

[0049] If the request is for level M+1 to level P, then the data for level M+1 to level P is obtained by upsampling the background tiles of level M in the low-precision tiles, and the corresponding tiles are returned.

[0050] In an exemplary embodiment, if there is a need to continue publishing new data, S5-S6 are repeated to continuously achieve tile generation, tile updating and fusion of high-precision data. Data publishing is achieved by maintaining an incrementally updated fused tile library.

[0051] In one exemplary embodiment, such as Figure 6 As shown, in order to facilitate the implementation of the embodiments of this application, in addition to establishing three types of databases, a multi-line cross-precision DEM data fusion system is also established, which includes the following modules.

[0052] The low-precision data processing module is used to slice low-precision background DEM data to generate background tiles covering the entire area, and generate a background pyramid corresponding to the level of the background tiles; based on the background tiles and the background pyramid, a low-precision tile library is constructed.

[0053] A high-precision data processing module is used to generate line tiles covering the perimeter of the line from corridor-type high-precision DEM data slices; and to construct a high-precision tile library based on the line tiles and their corresponding grades.

[0054] The high- and low-precision data fusion module is used to construct a fused tile library based on the line tiles and background tiles through transparency judgment, feathering fusion processing and sampling processing.

[0055] A new fusion update module is added to generate new tiles covering the perimeter of the newly added corridor-type high-precision DEM data slices and store them in the high-precision tile library; the new tiles are feathered and fused with the background tiles, and the newly fused tiles and the corresponding pyramids are stored in the fused tile library to obtain the updated fused tile library.

[0056] The data publishing module is used to output corresponding tile data from the low-precision tile library and the updated fused tile library based on low-level tile requests and high-level tile requests, so as to obtain cross-precision fused DEM data.

[0057] like Figure 7 As shown, this application uses the fusion of DEM data from multiple high-voltage transmission lines as a preferred embodiment for illustration.

[0058] (1) Analyze the data, preprocess the data, and construct three types of tile databases.

[0059] First, let's analyze the current data. The low-precision background DEM data is 10-meter resolution DEM data, and the appropriate level for constructing the background tile pyramid is level 6-13; the two transmission lines A and B are high-precision DEM data with a resolution of 0.5 meters, and the highest precision level for constructing the line tile pyramid is level 16.

[0060] Secondly, all DEM data are preprocessed, including unifying the format to TIFF and the spatial datum to WebMercator projection.

[0061] Finally, three types of tile libraries are constructed: LoResTile (low-precision tile library), HiResTile (high-precision tile library), and BlendTile (fusion tile library).

[0062] (2) Low-precision background DEM data slicing and pyramid construction.

[0063] Low-resolution (10-meter) DEM data is sliced ​​into background tiles, corresponding to levels 6-13. A pyramid is constructed for subsequent tile services, and all background tiles are stored in LoResTile (Low-Resolution Tile). Level 13 tile data is shown below. Figure 2 as shown in the figure. The tiles adopt the RGBA four-channel encoding format, and the transparency of the tile is recorded through the Alpha (transparency) channel. If the Alpha value of all pixels in the tile is 0, the tile is fully transparent; if the Alpha value is 255, the tile is fully opaque; in other cases, the tile is partially transparent.

[0064] (3) Slicing of high-precision DEM data for power line A.

[0065] The high-precision 0.5-meter resolution DEM data of power line A is sliced into line tiles, corresponding to level 16. The tiles are stored in HiResTile, and all tiles are marked as needs_blend=1. The level-16 data is as Figure 3 shown in the figure.

[0066] (4) Feathering fusion of the line tiles (level 16) corresponding to the high-precision DEM data and the background tiles (level 13) corresponding to the low-precision DEM data.

[0067] If the line tiles (level 16) corresponding to the high-precision DEM data are directly fused with the background tiles (level 13) corresponding to the low-precision DEM data, a step-like mutation will be formed at the edge where the two types of precision data meet, as Figure 4 shown in the figure, where the red area represents the mutation. To eliminate this situation, the fusion operation of the following steps is performed, and the fused data is as Figure 5 shown in the figure, where the mutation is eliminated and the transition at the joint edge is smooth.

[0068] Step 1.1: Traverse the tiles with needs_blend=1 in HiResTile.

[0069] Step 1.1.1: If the transparency Alpha of the line tile in this HiResTile is 255, that is, the coverage area of this line tile is completely high-precision DEM data, then store this tile in the fused tile library BlendTile.

[0070] Step 1.1.2: If the transparency Alpha of the line tile in this HiResTile satisfies 0<Alpha<255, that is, the coverage area of this line tile contains part of the high-precision DEM data, first perform upsampling on the background tile in the LoResTile library corresponding to the coverage area, that is, upsample level 13 step by step to level 14, level 15, and level 16 for temporary storage, then perform edge feathering fusion on the level-16 line tile in this HiResTile and the tile obtained by upsampling the background tile in LoResTile to level 16 just now to obtain a fused tile. The transparency of the fused tile is Alpha=255, the level is 16, the fused tile is stored in BlendTile, and it is marked as needs_blend=0.

[0071] So far, the transparency of all level-16 tiles in the coverage area of power line A is Alpha=255, which achieves high precision in the middle and a transition of precision from high to low at the edges.

[0072] Step 1.2: Mark the level-14 and level-15 tiles generated by upsampling in the LoResTile library in step 1.1.2 as needs_update=1. Downsample all level-16 tiles in the coverage area of power line A in step 1.1 to generate level-14 and level-15 tiles, to replace the tiles marked as needs_update=1 in step 1.2. Through this operation, the level-14 to level-16 tiles in the coverage area of power line A can ensure high precision and good fusion. After the operation, mark all involved tiles as needs_update=0.

[0073] (5) Slicing and fusion of additional high-precision DEM data for power line B.

[0074] Step 2.1: Slice the newly added high-precision 0.5-meter resolution DEM data of power line B to generate line tiles, corresponding to level 16.

[0075] Step 2.1: Calculate the corresponding tile coverage area of power line B, and compare it with the tile transparency Alpha of the tiles in the corresponding area of the current HiResTile.

[0076] Step 2.1.1: If Alpha=255 for the tiles in the corresponding area of the current HiResTile, which means the tiles of power line B and power line A overlap at this position, such as at the intersection center of the two power lines, directly use the tiles of power line B to cover the original tile data of power line A in HiResTile and store them in HiResTile.

[0077] Step 2.1.2: If 0<Alpha<255 for the tiles in the corresponding area of the current HiResTile, which means the tiles of power line B and power line A partially overlap at this position, such as at the edge of the intersection of the two power lines, perform a fusion operation (such as the DstOver operation) on the tiles of power line B and the original tiles of power line A in HiResTile, and then store the fused tiles in HiResTile.

[0078] Step 2.1.3: If Alpha=0 for the tiles in the corresponding area of the current HiResTile, it indicates that there is no tile data of power line A at this position and there is only tile data of power line B, then directly store the tiles of power line B into HiResTile.

[0079] After the above operations, HiResTile currently stores the terrain tiles at level 16 corresponding to the two corridor-type high-precision DEMs, A and B, and marks all newly added tiles with needs_blend=1.

[0080] (6) Feathering fusion of the line tiles (level 16) corresponding to the high-precision DEM data of the newly added transmission line B and the background tiles (level 13) corresponding to the low-precision DEM data.

[0081] Repeat steps 1.1-1.2 to update the newly merged tiles and pyramids to BlendTile.

[0082] Through the above operations, LoResTile stores the low-level tiles (levels 6-13) of the background DEM, and BlendTile stores the high-level tiles (levels 14-16) of the areas covered by transmission lines A and B.

[0083] (7) Tile data release.

[0084] Configure the tile data sources for LoResTile and BlendTile in accordance with the requirements of the tile data network.

[0085] When the request range is less than or equal to level 13, return the pyramid tile of the corresponding level in the current LoResTile.

[0086] When the request range is greater than level 13, check if there is corresponding data in the BlendTile: if there is, it means that there is data for two transmission lines A and B in this area, and the pyramid tile of the corresponding level in the current BlendTile is returned; if not, it means that there is no data for two transmission lines A and B in this area, and the tiles of levels 14 to 16 are returned by upsampling from level 13 tiles of LoResTile.

[0087] (8) If new high-precision data of transmission lines are added in the future, steps (5) and (6) can be repeated to continuously realize the generation, updating and fusion of high-precision data tiles and realize data release.

[0088] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 8As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs stored in the non-volatile storage media. The database is used for multi-line, cross-precision DEM data fusion. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. The computer program is executed by the processor to achieve multi-line, cross-precision DEM data fusion.

[0089] Those skilled in the art will understand that Figure 8 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0090] In one exemplary embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0091] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0092] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0093] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0094] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0095] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0096] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0097] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for fusing multi-line, cross-precision DEM data, characterized in that, include: Low-precision background DEM data is sliced ​​to generate background tiles covering the entire area, and the background tiles are then used to generate a background pyramid corresponding to their respective levels. Based on the background tiles and background pyramid, a low-precision tile library is constructed. High-precision DEM data of corridor type is sliced ​​to generate line tiles covering the perimeter of the line. Based on the line tiles and their corresponding grades, a high-precision tile library is constructed. Based on the line tiles and background tiles, a fused tile library is constructed through transparency judgment, feathering fusion processing, and sampling processing; The newly added corridor-type high-precision DEM data slices are used to generate new tiles covering the perimeter of the line, and stored in the high-precision tile library. The newly added tile is feathered and merged with the background tile, and the newly merged tile and the pyramid corresponding to the newly merged tile are stored in the merged tile library to obtain the updated merged tile library; Based on low-level tile requests and high-level tile requests, corresponding tile data are output from the low-precision tile library and the updated fused tile library to obtain cross-precision fused DEM data.

2. The multi-line cross-precision DEM data fusion method according to claim 1, characterized in that, The background tiles in the background pyramid are divided into levels N to M, where level N represents the low-precision level of the background tile; level M represents the high-precision level of the background tile; and the line tile corresponds to the highest precision level, level P. Wherein, N≥1, M>N, and P>>M.

3. The multi-line cross-precision DEM data fusion method according to claim 1, characterized in that, Based on the aforementioned line tiles and background tiles, a fused tile library is constructed through transparency judgment, feathering fusion processing, and sampling processing, specifically including: Mark all line tiles in the high-precision tile library as need_blend=1; where need_blend represents the tile to be blended; Determine whether the tile to be fused is completely opaque, and determine the first determination result; When the first judgment result is yes, it is determined that the coverage area of ​​the first line tile is completely high-precision DEM data, the first line tile is marked as needs_blend=0, and directly stored in the fused tile library; If the first judgment result is negative, then it is determined that the area covered by the second line tile is not entirely high-precision DEM data; The background tile is upsampled and fused with the second line tile to obtain a first fused tile of level P. The first fused tile is downsampled and processed to obtain a second fused tile of level M to P-1. The first fused tile and the second fused tile are stored together in the fused tile library.

4. The multi-line cross-precision DEM data fusion method according to claim 3, characterized in that, The background tiles are upsampled and then fused with the second line tiles to obtain a first fused tile of level P. The first fused tile is then downsampled and processed to obtain a second fused tile of levels M+1 to P-1. The first and second fused tiles are then jointly stored in a fused tile library. Specifically, this includes: Upsample the background tiles of level M in the low-precision tile library corresponding to the coverage area of ​​the second line tile to the background tiles of level M+1 to level P. Perform edge feathering and fusion of the background tiles of level P with the second line tile to obtain the first fused tile of level P, mark it as need_blend=0, and store it in the fused tile library. Background tiles upsampled to levels M+1 to P-1 are marked as need_update=1, indicating tiles that need to be updated; The first fused tile of level P in the fused tile library is merged and downsampled to generate the second fused tile of level M+1 to level P-1, which replaces the background tile of level M+1 to level P-1 with need_update=1, is marked as need_update=0, and stored in the fused tile library.

5. The multi-line cross-precision DEM data fusion method according to claim 1, characterized in that, The newly added corridor-type high-precision DEM data slices are used to generate new tiles covering the perimeter of the line, and stored in the high-precision tile library. Specifically, this includes: The newly added corridor-type high-precision DEM data slices are used to generate new tiles covering the area around the line, and then returned to the current high-precision tile library. Determine the transparency of the existing wiring tiles at the location of the new tile; If the existing line tile at the corresponding location is completely opaque, the new tile will cover the existing line tile, marked as need_blend=1, and stored in the high-precision tile library. If the existing line tile at the corresponding location is partially transparent, the newly added tile will be merged with the existing line tile, marked as need_blend=1, and stored in the high-precision tile library. If the existing line tile at the corresponding location is completely transparent, the newly added tile will be directly marked as need_blend=1 and stored in the high-precision tile library.

6. The multi-line cross-precision DEM data fusion method according to claim 1, characterized in that, The low-precision tile library stores background tiles of level N to M, and the fusion tile library stores second fusion tiles of level M+1 to P-1, first fusion tiles of level P, and first line tiles of level P.

7. A multi-line cross-precision DEM data fusion system, executing the multi-line cross-precision DEM data fusion method according to claims 1-6, comprising: The low-precision data processing module is used to slice low-precision background DEM data to generate background tiles covering the entire area, and to generate a background pyramid corresponding to the level of the background tiles. Based on the background tiles and background pyramid, a low-precision tile library is constructed. A high-precision data processing module is used to generate line tiles covering the lines from corridor-type high-precision DEM data slices; and to construct a high-precision tile library based on the line tiles and their corresponding grades. The high- and low-precision data fusion module is used to construct a fused tile library based on the line tiles and background tiles through transparency judgment, feathering fusion processing and sampling processing; A new fusion update module is added to generate new tiles covering the newly added corridor-type high-precision DEM data slices and store them in the high-precision tile library; the new tiles are feathered and fused with the background tiles, and the newly fused tiles and the corresponding pyramids are stored in the fusion tile library to obtain the updated fusion tile library; The data publishing module is used to output corresponding tile data from the low-precision tile library and the updated fused tile library based on low-level tile requests and high-level tile requests, so as to obtain cross-precision fused DEM data.

8. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the multi-line cross-precision DEM data fusion method according to any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the multi-line cross-precision DEM data fusion method as described in any one of claims 1-6.

10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the multi-line cross-precision DEM data fusion method as described in any one of claims 1-6.

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