how to super impose the label data information from lidar labeller app to original data

I have lablelled raw lidar data using Lidar labeler app in matlab and we know while saving the data we will just get the label data info not tje whole traffic scene, so now i want to super impose this label info to my original data so can you suggest me a code for it, or can you tell me any other way to save the label data from lidar labller app so it will save it as original with bounding boxes. Any way I need y data with bounding boxes.

Answer 1

[Hassaan]

1. Load the labeled data which contains the bounding box information.
2. Load the original LiDAR data (point cloud).
3. Use visualization functions to display the point cloud.
4. Overlay the bounding boxes onto the displayed point cloud.

% Load the labeled data from the MAT-file created by Lidar Labeler
labeledData = load('labeledData.mat');

% Load the original LiDAR data (replace with your actual file/data loading)
% It should match the labeled data in terms of dimensions and orientation
originalData = pcread('originalData.pcd'); % Example for .pcd files

% Display the original LiDAR data
pcshow(originalData.Location, 'VerticalAxis','Y', 'VerticalAxisDir', 'Down');
hold on;
title('LiDAR Data with Labeled Bounding Boxes');

% Assuming labeledData contains bounding boxes in a table format with variables
% 'Position' and 'Label' (update these variable names based on your labeledData structure)
for i = 1:size(labeledData.bbox, 1)
    % Extract the bounding box information
    bbox = labeledData.bbox.Position(i,:);
    label = labeledData.bbox.Label{i};
    
    % Define the corners of the bounding box
    x = bbox(1);
    y = bbox(2);
    z = bbox(3);
    w = bbox(4);
    l = bbox(5);
    h = bbox(6);
    
    % Define vertices of the bounding box
    vertices = [x, y, z; 
                x+w, y, z; 
                x+w, y+l, z; 
                x, y+l, z; 
                x, y, z+h; 
                x+w, y, z+h; 
                x+w, y+l, z+h; 
                x, y+l, z+h];
    
    % Define the faces of the bounding box
    faces = [1 2 3 4; 
             5 6 7 8; 
             1 2 6 5; 
             2 3 7 6; 
             3 4 8 7; 
             4 1 5 8];
    
    % Plot the bounding box
    patch('Vertices', vertices, 'Faces', faces, ...
          'EdgeColor', 'r', 'FaceColor', 'none', 'LineWidth', 1.5);
    
    % Add the label text
    text(x, y, z, label, 'Interpreter', 'none', 'Color', 'r');
end

hold off;

Please adjust the code to match your labeled data's structure. This example assumes that the bounding boxes are stored in a table with columns for the position and label, and that your LiDAR data is in a format that pcread can handle (like .pcd). If your data is in a different format, you'll need to use the appropriate function to load it.

This code will visualize your original LiDAR data and overlay the labeled bounding boxes. The loop goes through each label and draws a box at the specified position. The pcshow function is used to display the point cloud, and the patch function creates the wireframe boxes.

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It's important to note that the advice and code are based on limited information and meant for educational purposes. Users should verify and adapt the code to their specific needs, ensuring compatibility and adherence to ethical standards.

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[gaurav]

Hey, thank you for the response i tried to update the code acoording to my data but still i am getting errors I am attaching the labelled data mat file please look onto it and help me

[Hassaan]

What is the error?

[gaurav]

The error are based on data structures and multiple errors. Below I am providing the properties of my data

gTruth =

groundTruthLidar with properties:

DataSource: [1×1 vision.labeler.loading.PointCloudSequenceSource]

LabelDefinitions: [1×5 table]

LabelData: [500×1 timetable]

>> gTruth.DataSource

ans =

PointCloudSequenceSource with properties:

Name: "Point Cloud Sequence"

Description: "A PointCloud sequence reader"

SourceName: "C:\Users\asus\Desktop\Lidar\Lidar"

SourceParams: [1×1 struct]

SignalName: "Lidar"

SignalType: PointCloud

Timestamp: {[500×1 duration]}

NumSignals: 1

>> gTruth.LabelDefinitions

ans = 1×5

table Name Type LabelColor Group Description ______________ ______ ________________________ ________ ___________ {'Pedestrian'} Cuboid {[0.5862 0.8276 0.3103]} {'None'} {0×0 char}

>> gTruth.LabelData

ans =

500×1

timetable Time Pedestrian ___________ ____________ 00:00.00000 {3×9 double} 00:01.00000 {3×9 double} 00:02.00000 {4×9 double} 00:03.00000 {4×9 double} 00:04.00000 {4×9 double} 00:05.00000 {4×9 double} 00:06.00000 {4×9 double} : : 08:13.00000 {4×9 double} 08:14.00000 {4×9 double} 08:15.00000 {4×9 double} 08:16.00000 {4×9 double} 08:17.00000 {4×9 double} 08:18.00000 {4×9 double} 08:19.00000 {4×9 double}