How to change the axis/ or view in at point cloud plot. And how to remove unwanted background?

Hi Everybody :)

I am working with some lidar data (.txt file) which I have imported and plottet i matlab (I have attached the matlab code and the txt file I have used). I really want to change the axis/ or view when it gets plottet. Right now, the plot looks like this (se attached jpg), where I would really like to change the axis so it looks better visual. (I have tried to explain using the jpg, but if possible I would like to look at it from the front of the fence).

I also have another question for removing background and noise. So that i in the end, is only looking at the fence pattern and nothing else.

And a last thing, is there someone who can help me with saving all x,y,z points for all the scans, instead of that I only save the last x,y,z scan points in the workspace :)

Answer 1

[Raj Bhakta]

Hi Annizette,

1. You can use the view function to change the location of your camera position in your plot. See https://www.mathworks.com/help/matlab/ref/view.html
2. It looks like you have a threshold, what you call ceiling, in your plots that you want to hide. You can remove this data from your dataset by using:

background = x_points < -1500; % Arbitrary threshold at -1500
x_points(background == 1) = []; % This removes the points where x_points < -1500 from your dataset
y_points(background == 1) = [];
z1(background == 1) = [];

% Plot remaining x, y, and z points
Fence = [x_points(:),y_points(:),z1(:)];
pcshow(Fence);

3. To save your points per scan, put your save command at the end of your primary for loop (blocks loop). Use the save command to do this:

save(strcat(string,'.mat'),'x_points','y_points','z1');

This assumes your string value changes every iteration, so you create a new .mat file for each dataset that contains the x,y, and z points.

Hope this helps.