3D Point Cloud Edge

Operator Function

For the selected point cloud, output the 3D edge points of its XY plane projection.

Parameter Introduction

Input Parameters

Parameter	Range	Default Value	Description	Illustration
Input Image	0-8	0	The IM number for image input

Calculation Parameters

Parameter	Range	Default Value	Description	Illustration
Use Region Parameters	true/false	false	If enabled, use Region as input; if not enabled, use Input Image as input
Region	2D Window/2D Circular Window/2D Polygon Window/Box/Cylinder Box/Rotated Box/Point Set (binding only)	Box	Manually select an appropriate ROI region Can bind to select existing ROI regions
Extraction Mode	Latitude-Longitude Sweep/Concave Hull Algorithm/Normal Vector Extraction	Concave Hull Algorithm	Set extraction method. Latitude-Longitude Sweep is suitable for line scan camera images; Concave Hull Algorithm is suitable for projects with high accuracy requirements and relatively relaxed time constraints; Normal Vector Extraction is suitable for point clouds with significant curvature changes
Resolution	1-3000	5	Resolution for Latitude-Longitude Sweep point cloud extraction; higher resolution extracts more edge points
Edge Point Density	0.1-1.0	0.5	Set edge point density for Concave Hull Algorithm; higher values extract more edge points but take more time
K-Nearest Neighbors	1-500	10	Determines number of neighbors considered for boundary estimation; higher values ignore local details; adjust to balance noise and local details
Search Radius	0.01-100.0	0.05	Local range for normal vector calculation; affects normal vector estimation accuracy and noise resistance; increase for high-density point clouds to smooth noise; decrease for sparse point clouds to preserve details
Angle Threshold	0-180	120	Higher values needed for more complex point clouds; threshold for normal vector angle to determine boundary points; values exceeding this are considered boundaries; generally set to 180 when extracting projection plane boundaries

Result Display

Parameter	Range	Default Value	Description	Illustration
Boundary	true/false	false	Extracted 3D edge points

Output Parameters

Name	Type	Range	Description
Result	bool	true/false	true for success false for failure
Warning	bool	true/false	true indicates there is a warning false indicates there is none
Message	string		Outputs success, error, or warning information; if there is no error or warning, it is empty
Time	float		Operator execution time, unit: ms
boundary	pointset		Edge point cloud

Tip

For more detailed explanations of parameter types, please refer to Type Definitions

Exception Troubleshooting

No.	Exception Information	Corresponding Parameter	Solution
1	Input region type is {0}, invalid region type	Region Type	Region input type must be one of: 2D Window/2D Circular Window/2D Polygon Window/Box/Cylinder Box/Rotated Box/Point Set
2	Region is empty		1. Check if selection is empty 2. Check if point set is empty
3	Input point cloud is empty		Confirm if IM contains valid points; if no valid points, load point cloud or switch to IM with valid points
4	Output edge is empty		Adjust parameters of relevant mode
5	Input extraction mode is {0}, invalid extraction mode	Extraction Mode	Set extraction mode to one of: Latitude-Longitude Sweep/Concave Hull Algorithm/Normal Vector Extraction
6	Input polygon vertex count less than 3, cannot form polygon		Add 2D polygon window vertices so vertex count is at least three

Example Introduction

Engineering Design

1. Select the Load Point Cloud tool to load the 3D point cloud image to be processed into IM0;

2. Select the 3D Point Cloud Edge tool.

Tool Usage

3. Select the input image for operation; the image number must match the IM number where the image is located in the project.

4. Either do not enable Use Region Parameters, or enable region and select region type as Box, move the box to the position to be measured, enclosing the point cloud to be measured.

Usage Tips

1. Use the ROI controller on the image window to drag or scale the box;
2. Directly modify the start or end coordinates of the box in the calculation parameters to adjust the box position and size.

5. Set parameters

6. Check the content you want to display in the result display section

7. Click Test to check if the image window and parameters meet expectations

8. If there are no issues, click Save, then run the operator in the run list to view the results in the corresponding IM

Latitude-Longitude Sweep Method

Concave Hull Method

Normal Vector Extraction Method