Euclidean Clustering Segmentation

Functional Description

This operator performs clustering segmentation on the input point cloud based on the Euclidean distance between points. It aggregates points that are spatially close to each other into independent clusters. If the distance between a point and any point in an existing cluster is less than the set "Search radius in", or if it can be connected to a point within the radius, then this point is assigned to that cluster. The operator finally outputs a list of point clouds, where each point cloud in the list represents a segmented cluster.

Usage Scenarios

  • Instance Segmentation: Segmenting physically separated objects in a scene into independent point cloud clusters. For example, segmenting multiple parts on a conveyor belt, or multiple cups on a table.

  • Noise Removal: By setting "Clustering minimum points", it can effectively filter out point cloud clusters that have too few points and are likely background noise or sensor errors.

  • Point Cloud Preprocessing: Before tasks such as object recognition and pose estimation, segmenting the original point cloud or point cloud within an ROI into units representing different objects.

  • The function is very similar to the "Connected Component Segmentation" operator, usually both utilize spatial proximity for clustering.

Input/Output

Input Items

Pointcloud: The input point cloud or list of point clouds to be segmented.

Output Items

Split point cloud: The list of point cloud clusters obtained after segmentation.

Parameter Description

This operator has two versions:

  • Euclidean Clustering Segmentation: Processes point clouds without normal information.

  • Euclidean Clustering Segmentation(with Normals): Processes point clouds with normal information.

Both have identical core functions and parameters, only differing in the type of point cloud data processed.

Search radius in

Parameter Description

Defines the maximum distance threshold for a point to be added to a cluster during the clustering process. This is also the search radius when finding neighboring points.

Tuning Description

  • Decrease this value: Makes the clustering condition stricter, only very close points will be grouped into the same cluster, potentially leading to one object being split into multiple small clusters, or making it easier to separate objects that are very close.

  • Increase this value: Makes the clustering condition looser, points that are slightly further apart may also be grouped into one cluster, potentially merging different objects.

Parameter Range

[0, 200], Default Value: 5, Unit: mm

Clustering minimum points

Parameter Description

Minimum number of Point Cloud Points per Cluster.

Tuning Description

Used to filter out point cloud clusters that are too small. Increasing this value can remove more small clusters (usually considered noise), but if set too high, it may filter out small valid objects.

Parameter Range

[1, 4000000], Default Value: 100

Clustering max points

Parameter Description

Maximum number of Point Cloud Points per Cluster.

Tuning Description

Used to filter out point cloud clusters that are too large. Applicable to scenarios where oversized clustering results such as background or ground need to be excluded. Usually, the default value (a very large number) is sufficient, unless there is a special need.

Parameter Range

[1, 4000000], Default Value: 4000000

Retain all results

Parameter Description

For each input point cloud, whether to output all the split results, if false, the specified number of results will be retained.

Tuning Description

  • Enabled (default): Retains all cluster_list filtered by minimum/maximum points.

  • Disabled: Only retains the top N cluster_list with the most points, N is specified by the "Number of retention results" parameter.

Number of retention results

Parameter Description

Takes effect when "Retain all results" is set to disabled. Specifies the number of cluster_list with the most points to retain.

Tuning Description

The operator will first sort all segmentation results by the number of point clouds from largest to smallest. If this parameter is set to N, only the top N point cloud clusters after sorting will be output. For example, setting it to 1 means only the cluster with the most points will be output.

Parameter Range

[1, 1000], Default Value: 1

Enable sorting

Parameter Description

Determines whether to sort the final output list of point cloud clusters by the number of points from largest to smallest.

Tuning Description

  • Enabled (default): The output list of point clouds is sorted by the number of points from most to fewest.

  • Disabled: The order of the output list of point clouds is uncertain.

If subsequent processing depends on the size order of the point cloud clusters, this item should be kept enabled.

Enable node

Parameter Description

Controls whether this operator performs calculations.

Tuning Description

  • Enabled (default): The operator functions normally.

  • Disabled: The operator does not perform any operations and directly outputs the input data.