select

Select points in point cloud

Syntax

ptCloudOut = select(ptCloud,indices)

ptCloudOut = select(ptCloud,row,column)

ptCloudOut = select(___,OutputSize=outputSize)

Description

ptCloudOut = select(ptCloud,indices) returns a pointCloud object containing only the points that are selected using linear or logical indices.

ptCloudOut = select(ptCloud,row,column) returns a pointCloud object containing only the points that are selected using row and column subscripts. This syntax applies only if the input is an organized point cloud data of size M-by-N-by-3.

ptCloudOut = select(___,OutputSize=outputSize) returns the selected points as a pointCloud object of size specified by outputSize.

Examples

Select Points from Point Cloud

Read a point cloud data into the workspace.

ptCloud = pcread("teapot.ply");

Read the number of points in the point cloud data.

Length = ptCloud.Count;

Select indices within the range [1, Length].

stepSize = 10;
indices = 1:stepSize:Length;

Select points specified by the indices from input point cloud. This selection of points downsamples the input point cloud by a factor of stepSize.

ptCloudB = select(ptCloud,indices);

Display the input and the selected point cloud data.

figure
subplot(1,2,1)
pcshow(ptCloud)
title("Input Point Cloud",Color=[1 1 1]);
subplot(1,2,2)
pcshow(ptCloudB)
title("Selected Points",Color=[1 1 1]);

Input Arguments

ptCloud — Point cloud

pointCloud object

Point cloud, specified as a pointCloud object.

indices — Linear or logical indices of selected points

vector | matrix

Linear or logical indices of selected points, specified as a vector or a matrix. For organized point clouds, indices (linear or logical), refer only to the first two dimensions of the Location property.

row — Row indices

vector

Row indices, specified as a vector. This argument applies only if the input is an organized point cloud with the Location data of size M-by-N-by-3.

column — Column indices

vector

Column indices, specified as a vector. This argument applies only if the input is an organized point cloud with the Location data of size M-by-N-by-3.

outputSize — Size of output point cloud

"selected" (default) | "full"

Size of the output point cloud, ptCloudOut, specified as "selected" or "full".

• If the size is "selected", then the output contains only the selected points from the input point cloud, ptCloud.

• If the size is "full", then the output is same size as the input point cloud ptCloud. Cleared points are filled with NaN and the color is set to [0 0 0].

• When working with organized point clouds and to return an organized point cloud, set outputSize to "full".

Output Arguments

ptCloudOut — Selected point cloud

pointCloud object

Point cloud, returned as a pointCloud object.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

The input argument outputSize must be compile-time constant. For example,

outputSize = coder.Constant('full');

If you use the coder (MATLAB Coder) app, you can choose the outputSize by right-clicking on it and select Define Constant.

GPU Code Generation
Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Version History

Introduced in R2015a