Lidar Point Cloud 3D Show

Hi

I have a problem to show lidar point cloud by "build lidar map" example.

I took step by step, but only for the lidar sensor. I changed timerange field function inorder to adjust time and ptCloud values to the lidar variables, but I can not see point cloud on my figure.

Note - there is not complier error.

Please help.

my code:

data = load('lidarPointClouds');
lidarPointClouds = data.lidarPointClouds;
head(lidarPointClouds);%8x1 timetable
lidarFrameDuration = median(diff(lidarPointClouds.Time));
lidarFrameDuration.Format = 's';%Adjust display format to sec
lidarRate = 1/seconds(lidarFrameDuration);%Frame rates
%Display frame durations and rates
fprintf('Lidar:%s %3.1f Hz\n',char(lidarFrameDuration),lidarRate);
%Customize axis
xlimits = [-45 45];
ylimits = [-45 45];
zlimits = [-10 20];
lidarPlayer = pcplayer(xlimits,ylimits,zlimits);
xlabel(lidarPlayer.Axes,'X(m)');
ylabel(lidarPlayer.Axes,'Y(m)');
zlabel(lidarPlayer.Axes,'Z(m)');
title(lidarPlayer.Axes,'Lidar Sensor Data');
% Reading Lidar Point Cloud by a loop
lidarFrames = 0; timeSpan = 0 ;ptCloud = 0;
for i = 1:height(timetable)-1
    timeSpan = timerange(lidarPointClouds.Time(1),lidarPointClouds.Time(1000),'closed');
    lidarFrames = lidarPointClouds(timeSpan,:);
    ptCloud = lidarFrames.PointCloud(i);
    view(lidarPlayer,ptCloud);
    pause(0.01);
end

[Walter Roberson]

You appear to have posted your question twice ?

[Elad Soll]

Yes , sorry .. it's my first time asking for a question and i am pretty new at matlab

[aws hawary]

Hello

I have a question if anyone could help me

I got Data LIDAR files ( pcap and csv)

I wanna to apply that data but the files should be compatible with MATLAB platform .. How can I read all the frames of ply file .. I read the total of pcap but I need the frames #separately for each timestamp

[Walter Roberson]

https://www.mathworks.com/help/vision/ref/velodynefilereader.html and readFrame() to read one frame at a time ?

Answer 1

[Sai Bhargav Avula]

Hi,

Here is updated code that works for simple lidarPointCloud. I think the issue with your code is 'timetable' wasnot defined properly

 data = load('lidarPointClouds.mat');
lidarPointClouds = data.lidarPointClouds;
head(lidarPointClouds);%8x1 timetable
lidarFrameDuration = median(diff(lidarPointClouds.Time));
lidarFrameDuration.Format = 's';%Adjust display format to sec
lidarRate = 1/seconds(lidarFrameDuration);%Frame rates
%Display frame durations and rates
fprintf('Lidar:%s %3.1f Hz\n',char(lidarFrameDuration),lidarRate);
%Customize axis
xlimits = [-45 45];
ylimits = [-45 45];
zlimits = [-10 20];
lidarPlayer = pcplayer(xlimits,ylimits,zlimits);
xlabel(lidarPlayer.Axes,'X(m)');
ylabel(lidarPlayer.Axes,'Y(m)');
zlabel(lidarPlayer.Axes,'Z(m)');
title(lidarPlayer.Axes,'Lidar Sensor Data');
% Reading Lidar Point Cloud by a loop
lidarFrames = 0; timeSpan = 0 ;ptCloud = 0;
timeSpan = timerange(lidarPointClouds.Time(1),lidarPointClouds.Time(1000),'closed');
lidarFrames = lidarPointClouds(timeSpan,:);
for i = 1:height(lidarFrames)-1
    
    ptCloud = lidarFrames.PointCloud(i);
    view(lidarPlayer,ptCloud);
    pause(0.01);
end

Hope this helps!

[aws hawary]

Hello

I have a question if anyone could help me

I got Data LIDAR files ( pcap and csv)

I wanna to apply that data but the files should be compatible with MATLAB platform .. How can I read all the frames of ply file .. I read the total of pcap but I need the frames #separately for each timestamp

[Anand]

If you have the PCAP file, you can use the velodyneFileReader class to read frames from it using the readFrame function.

If you have PLY files, you can use the pcread function to read each PLY file.