CN113487736B - Method for converting underwater topography point cloud data into OBJ three-dimensional model - Google Patents
Method for converting underwater topography point cloud data into OBJ three-dimensional model Download PDFInfo
- Publication number
- CN113487736B CN113487736B CN202110785969.4A CN202110785969A CN113487736B CN 113487736 B CN113487736 B CN 113487736B CN 202110785969 A CN202110785969 A CN 202110785969A CN 113487736 B CN113487736 B CN 113487736B
- Authority
- CN
- China
- Prior art keywords
- point cloud
- obj
- cloud data
- dimensional model
- grid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000012876 topography Methods 0.000 title claims abstract description 33
- 238000006243 chemical reaction Methods 0.000 claims abstract description 14
- 238000007781 pre-processing Methods 0.000 claims description 4
- 150000001875 compounds Chemical class 0.000 claims 1
- 238000012545 processing Methods 0.000 abstract description 3
- 238000013461 design Methods 0.000 abstract description 2
- 238000005259 measurement Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/05—Geographic models
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Geometry (AREA)
- Software Systems (AREA)
- Computer Graphics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Remote Sensing (AREA)
- Processing Or Creating Images (AREA)
Abstract
The invention relates to the technical field of underwater point cloud data processing and three-dimensional modeling, in particular to a method for converting underwater topography point cloud data into an OBJ three-dimensional model. The method comprises the steps of firstly obtaining an original underwater topography point cloud data set Ds obtained by an underwater topography measuring system, then converting the original underwater topography point cloud data set Ds into topography point cloud data with real geographic coordinates, then constructing a regular grid DEM model, and finally converting the regular grid DEM model into an OBJ three-dimensional model and storing the OBJ three-dimensional model, so that conversion from the underwater topography point cloud data to the OBJ three-dimensional model is realized. The method has the characteristics of reasonable design, high automation degree, high efficiency, good accuracy, low cost and the like.
Description
Technical Field
The invention belongs to the technical field of underwater point cloud data processing and three-dimensional modeling, and particularly relates to a method for converting underwater topography point cloud data into an OBJ three-dimensional model.
Background
In the processing of underwater topography point cloud data, only a DEM (raster model or contour model) result of the underwater topography is required to be obtained usually. And then a complete topographic map product is obtained by combining the onshore topographic measurement result. From a product form point of view, the topography is still only a two-dimensional product.
With the rapid development of the oblique photogrammetry technology of unmanned aerial vehicles, the oblique live-action three-dimensional model gradually becomes one of the main forms of three-dimensional product submission, and the demand of people on three-dimensional products becomes larger and larger. Therefore, it is also necessary to produce three-dimensional products from underwater topography measurements.
The three-dimensional model in the OBJ format mainly comprises vertex coordinate information, texture coordinate information, normal vector information, face index information and the like, and is simple in file structure and very wide in application. Therefore, the invention adopts the OBJ format as the result format of the three-dimensional model.
Disclosure of Invention
The invention aims to solve the problem of the defects existing in the submission of the existing underwater topography measurement product, and provides a method for converting underwater topography point cloud data into an OBJ three-dimensional model.
A method for converting underwater topography point cloud data into an OBJ three-dimensional model comprises the following steps:
(1) Traversing each point in the point cloud data set Ds, and performing homing calculation by using related parameter data (sound velocity profile data, attitude parameters and the like) to obtain coordinate data of each point in a ship body coordinate system;
(2) And performing coordinate conversion by using the navigation positioning data and the conversion relation between the ship body coordinate system and the geographic coordinate system to obtain a terrain point cloud data set Dr with a real geographic coordinate.
(3) And (3) repeating the processes (1) and (2) until all points are calculated.
(1) Setting DEM grid size d and grid range (MinX, minY, maxX, maxY), and creating a regular grid;
(2) Traversing each node of the regular grid;
(3) Searching a point cloud data set Dc which takes the current node as the center of a circle and has the radius of d/2 from the point cloud data set Dr, and assigning the elevation of the point to the current node if only one point data is contained in Dc; if the data point in Dc is larger than 1, assigning the average value of the elevations of all data points in Dc to the current node; if Dc is empty, the current node is marked as an invalid node;
(4) And (5) repeating the processes (2) to (3) until all the grid nodes are traversed.
And 4, converting the regular grid DEM model into an OBJ three-dimensional model and storing the OBJ three-dimensional model. The method comprises the following specific steps:
(1) Dividing each grid of the regular grid DEM by a diagonal line;
(2) Traversing the grid nodes, extracting all effective nodes as a vertex data set V { V | V | of the OBJ three-dimensional model i (x i ,y i ,z i )∈V}；
(3) All triangles are traversed, the indexes of the three vertexes of the triangles in the data set V are found (starting from 1), and a face index data set F { F | F is constructed i (v i ,v j ,v k ) E is F and v i ∈V，v j ∈V，v k ∈V}；
The calculation formula of the current node coordinate in step 3 of the present invention is as follows, and the current node is set as the ith node in the X-axis direction and the jth node in the Y-axis direction,
wherein d is the mesh size.
(4) And saving the vertex data set V and the face index data set F according to the format of the OBJ three-dimensional model file.
When the grid is divided in the step 4, if four grid points of the current grid are all effective nodes, one diagonal line is arbitrarily selected for dividing; if the current grid has an invalid node, only the remaining three valid nodes form a triangle; if two or more invalid nodes exist in the current grid, the current grid does not need to be triangulated.
The invention has the advantages of reasonable design, high automation degree, high efficiency, good accuracy, low cost and the like. The concrete embodiment is as follows:
1. the invention uses the OBJ format three-dimensional model as the three-dimensional result of the underwater topography measurement result, and the file structure is simple, the use is wide, and the popularization and the application are convenient.
2. The invention constructs the regular grid DEM by using the underwater terrain data, can ensure the integrity and authenticity of the underwater terrain to a certain extent while reducing the total data amount, and is convenient for establishing the triangular vertex index.
3. The invention realizes the conversion from underwater topography point cloud data to an OBJ three-dimensional model, so that underwater topography measurement data can form a three-dimensional product result, and an overwater and underwater integrated three-dimensional product can be formed by combining with an onshore three-dimensional model result.
4. The invention has high automation degree, basically does not need manual intervention in the conversion process, and can directly obtain the conversion result.
Drawings
FIG. 1 is an overall process flow diagram of the present invention;
FIG. 2 is a process flow diagram of step 2;
FIG. 3 is a flowchart of the process of step 3;
FIG. 4 is a flowchart of the process of step 4;
FIG. 5 is a DEM model schematic diagram constructed by a certain section of underwater measurement data;
FIG. 6 is a schematic diagram of a converted three-dimensional model in an OBJ format;
fig. 7 is an example of the converted OBJ file.
Detailed Description
Example 1: a method for converting underwater topography point cloud data into an OBJ three-dimensional model comprises the following steps:
(1) Traversing each point in the point cloud data set Ds, and performing homing calculation by using related parameter data (sound velocity profile data, attitude parameters and the like) to obtain coordinate data of each point in a ship body coordinate system;
(2) And performing coordinate conversion by using the navigation positioning data and the conversion relation between the ship body coordinate system and the geographic coordinate system to obtain a terrain point cloud data set Dr with a real geographic coordinate.
(3) And (3) repeating the processes (1) and (2) until all points are calculated.
(1) Setting DEM grid size d and grid range (MinX, minY, maxX, maxY), and creating a regular grid;
(2) Traversing each node of the regular grid;
(3) Searching a point cloud data set Dc with the current node as the center of a circle and the radius of d/2 from the point cloud data set Dr, and assigning the point elevation to the current node if only one point data is contained in Dc; if the data point in Dc is larger than 1, assigning the average value of the elevations of all data points in Dc to the current node; if Dc is empty, the current node is marked as an invalid node;
(4) And (5) repeating the processes (2) to (3) until all the grid nodes are traversed.
FIG. 5 is a schematic diagram of a DEM model constructed by a certain section of underwater measurement data.
And 4, converting the regular grid DEM model into an OBJ three-dimensional model and storing the OBJ three-dimensional model. The method comprises the following specific steps:
(1) Dividing each grid of the regular grid DEM by a diagonal line;
(2) Traversing the grid nodes, extracting all effective nodes as a vertex data set V { V | V | of the OBJ three-dimensional model i (x i ,y i ,z i )∈V}；
(3) All triangles are traversed, the indexes of three vertexes of the triangles in the data set V are found (starting from 1), and a face index data set F { F | F is constructed i (v i ,v j ,v k ) E is F and v i ∈V，v j ∈V，v k ∈V}；
The calculation formula of the current node coordinate in step 3 of the present invention is as follows, and the current node is set as the ith node in the X-axis direction and the jth node in the Y-axis direction,
wherein d is the mesh size.
(4) And saving the vertex data set V and the face index data set F according to the format of the OBJ three-dimensional model file.
When the grid is divided in the step 4, if four grid points of the current grid are all effective nodes, one diagonal line is arbitrarily selected for dividing; if the current grid has an invalid node, only the remaining three valid nodes form a triangle; if two or more invalid nodes exist in the current grid, the current grid does not need to be triangulated.
Fig. 6 is a schematic diagram of the converted OBJ format three-dimensional model.
Fig. 7 is an example of the converted OBJ file.
The foregoing is only a part of the specific embodiments of the present invention and specific details or common general knowledge in the schemes have not been described herein in more detail. It should be noted that the above-mentioned embodiments do not limit the present invention in any way, and it is obvious for those skilled in the art that all the technical solutions obtained by using the equivalent substitution or the equivalent change fall within the protection scope of the present invention. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (7)
1. A method for converting underwater topography point cloud data into an OBJ three-dimensional model is characterized by comprising the following steps: step 1, obtaining an original underwater topography point cloud data set Ds obtained by an underwater topography measuring system;
step 2, preprocessing data: performing homing calculation and coordinate conversion to obtain topographic point cloud data with real geographic coordinates;
step 3, constructing a regular grid DEM model; the method comprises the following specific steps:
(1) Setting DEM grid sizedAnd grid range: minX, minY, maxX, maxY, creating a regular grid;
(2) Traversing each node of the regular grid;
(3) Searching out the point cloud data set Dr with the current node as the center of a circle and the radius as the radiusdPoint cloud data set Dc in the range of/2, if Dc only contains one point data, assigning the point elevation to the current node; if the data point in Dc is larger than 1, assigning the average value of the elevations of all data points in Dc to the current node; if Dc is empty, the current node is marked as an invalid node;
(4) Repeating the processes (2) to (3) until all grid nodes are traversed;
and 4, converting the regular grid DEM model into an OBJ three-dimensional model and storing the OBJ three-dimensional model.
2. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 1, wherein said step 2, by data preprocessing: the method comprises the following steps of performing homing calculation and coordinate conversion to obtain topographic point cloud data with real geographic coordinates, and specifically comprises the following steps:
(1) Traversing each point in the point cloud data set Ds, and utilizing the related parameter data: performing homing calculation on the sound velocity profile data and the attitude parameters to obtain coordinate data of each point under a hull coordinate system;
(2) Performing coordinate conversion by using the navigation positioning data and the conversion relation between the ship body coordinate system and the geographic coordinate system to obtain a terrain point cloud data set Dr with a real geographic coordinate;
(3) And (3) repeating the processes (1) and (2) until all points are calculated.
3. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 1, wherein the step 4 of converting the regular grid DEM model into the OBJ three-dimensional model and storing the OBJ three-dimensional model comprises the following specific steps:
(1) Dividing each grid of the regular grid DEM by a diagonal line;
(2) Traversing the grid nodes, extracting all effective nodes as a vertex data set V { V _ computation of the OBJ three-dimensional modelv i （x i , y i , z i ）∈V}；
(3) Traversing all triangles, finding out indexes of three vertexes of the triangles in the data set V, and constructing a face index data set F { Ff i （v i , v j , v k ) Is e.g. F andv i ∈V，v j ∈V，v k ∈V }；
(4) And saving the vertex data set V and the face index data set F according to the format of the OBJ three-dimensional model file.
4. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 1, wherein the calculation formula of the current node coordinates in the step 3 is as follows, and the current node is the second node in the X-axis directioniOne node, the first in the Y-axis directionjThe number of the nodes is equal to that of the nodes,
in the formula (I), the compound is shown in the specification,dis the size of the grid.
5. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 3, wherein when the grid is subdivided in the step 4, if four grid points of the current grid are all valid nodes, one diagonal line is arbitrarily selected for subdivision.
6. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 3, wherein when the mesh is divided in the step 4, if there is an invalid node in the current mesh, the remaining three valid nodes form a triangle.
7. The method for converting underwater topography point cloud data into an OBJ three-dimensional model according to claim 3, wherein when the mesh is divided in step 4, if two or more invalid nodes exist in the current mesh, the current mesh is not triangulated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110785969.4A CN113487736B (en) | 2021-07-12 | 2021-07-12 | Method for converting underwater topography point cloud data into OBJ three-dimensional model |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110785969.4A CN113487736B (en) | 2021-07-12 | 2021-07-12 | Method for converting underwater topography point cloud data into OBJ three-dimensional model |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113487736A CN113487736A (en) | 2021-10-08 |
| CN113487736B true CN113487736B (en) | 2022-12-02 |
Family
ID=77938760
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110785969.4A Active CN113487736B (en) | 2021-07-12 | 2021-07-12 | Method for converting underwater topography point cloud data into OBJ three-dimensional model |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113487736B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117932974B (en) * | 2024-03-21 | 2024-06-18 | 威海水利工程集团有限公司 | Construction method of reservoir underwater digital elevation model |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107833281A (en) * | 2017-11-09 | 2018-03-23 | 长江三峡勘测研究院有限公司（武汉） | A kind of quick method for establishing geology free face GOCAD three-dimensional geological models |
| CN112634431A (en) * | 2020-11-24 | 2021-04-09 | 武汉科瑞斯特三维科技有限公司 | Method and device for converting three-dimensional texture map into three-dimensional point cloud |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107798728B (en) * | 2017-10-18 | 2020-10-20 | 中国电建集团中南勘测设计研究院有限公司 | Surface three-dimensional model construction method based on laser point cloud data |
| CN107730585A (en) * | 2017-11-06 | 2018-02-23 | 济南市市政工程设计研究院（集团）有限责任公司 | A kind of landform threedimensional model generation method and system |
| CN108413926B (en) * | 2018-01-31 | 2020-12-04 | 上海荟蔚信息科技有限公司 | High-precision measurement method for underwater topography elevation of pile foundation of offshore wind farm |
| US10839264B2 (en) * | 2018-11-09 | 2020-11-17 | International Business Machines Corporation | Scalable feature classification for laser scanning data and digital elevation models |
| CN110415345B (en) * | 2019-07-01 | 2023-01-24 | 南京泛在地理信息产业研究院有限公司 | Method and system for converting ESRI TIN model into OBJ three-dimensional model |
| CN110570466B (en) * | 2019-09-09 | 2022-09-16 | 广州建通测绘地理信息技术股份有限公司 | Method and device for generating three-dimensional live-action point cloud model |
| CN111145350B (en) * | 2019-12-25 | 2023-01-31 | 中国电建集团中南勘测设计研究院有限公司 | Three-dimensional dynamic rendering display method for flood risk analysis result data |
| CN112270750B (en) * | 2020-10-15 | 2022-06-10 | 昆明理工大学 | Method for reconstructing water and underwater integrated three-dimensional model of karst cave |
-
2021
- 2021-07-12 CN CN202110785969.4A patent/CN113487736B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107833281A (en) * | 2017-11-09 | 2018-03-23 | 长江三峡勘测研究院有限公司（武汉） | A kind of quick method for establishing geology free face GOCAD three-dimensional geological models |
| CN112634431A (en) * | 2020-11-24 | 2021-04-09 | 武汉科瑞斯特三维科技有限公司 | Method and device for converting three-dimensional texture map into three-dimensional point cloud |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113487736A (en) | 2021-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2021203711A1 (en) | Isogeometric analysis method employing geometric reconstruction model | |
| CN103729872B (en) | A kind of some cloud Enhancement Method based on segmentation resampling and surface triangulation | |
| CN115372989A (en) | Laser radar-based long-distance real-time positioning system and method for cross-country automatic trolley | |
| CN105654483A (en) | Three-dimensional point cloud full-automatic registration method | |
| CN115661374B (en) | Rapid retrieval method based on space division and model voxelization | |
| CN112651889A (en) | Fusion filtering method suitable for SLAM point cloud denoising, electronic device and storage medium | |
| CN117475084B (en) | Method and system for generating curtain wall three-dimensional wire frame model | |
| CN116543310B (en) | Road line extraction method based on Voronoi diagram and kernel density | |
| CN114332291A (en) | Oblique photography model building outer contour rule extraction method | |
| CN113487736B (en) | Method for converting underwater topography point cloud data into OBJ three-dimensional model | |
| Sacchi et al. | Curvature estimation for segmentation of triangulated surfaces | |
| CN110675323A (en) | Three-dimensional map semantic processing method, system, equipment and computer medium | |
| CN105931297A (en) | Data processing method applied to three-dimensional geological surface model | |
| CN105869210A (en) | Interpolation data processing method in three-dimensional geological surface model | |
| CN111598941A (en) | Method, device and equipment for measuring gradient of tower and storage medium | |
| CN113609691B (en) | Intersection modeling processing method oriented to intelligent traffic simulation | |
| CN115114870A (en) | Method and system for generating spliced three-dimensional surface structure grid based on block mapping | |
| CN114660611A (en) | Fusion method of airborne LiDAR depth sounding and multi-beam sonar depth sounding point cloud | |
| WO2021250734A1 (en) | Coordinate conversion device, coordinate conversion method, and coordinate conversion program | |
| Liu et al. | Line simplification algorithm implementation and error analysis | |
| CN105869209A (en) | Deformed triangular data processing method in three-dimensional geological surface model | |
| Shen et al. | An adaptive triangulation optimization algorithm based on empty circumcircle | |
| CN113066151B (en) | Map data processing method, device, equipment and storage medium | |
| CN113327328B (en) | Three-dimensional point cloud data compaction method | |
| CN116051782B (en) | Data processing and reconstruction modeling method, device and storage medium based on orthogonal grid curve interpolation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20230410 Address after: 650000 Office Building No. 115 Renmin East Road, Kunming City, Yunnan Province Patentee after: POWERCHINA KUNMING ENGINEERING Corp.,Ltd. Patentee after: LUBUGE HYDROPOWER PLANT OF SOUTHERN POWER GRID PEAKING FREQUENCY MODULATION POWER GENERATION CO.,LTD. Address before: 650000 Office Building No. 115 Renmin East Road, Kunming City, Yunnan Province Patentee before: POWERCHINA KUNMING ENGINEERING Corp.,Ltd. |
|
| TR01 | Transfer of patent right |