Questions tagged [lidar]
LIDAR (Light Detection and Ranging or Laser Imaging, Detection and Ranging) is an active optical remote sensing technology that measures properties of scattered light to find range and/or other information of a distant target.
915
questions
0
votes
1
answer
40
views
Convert a RGB LiDAR raster image to a greyscale height map in QGIS [closed]
I am fairly new to the world of GIS and also using QGIS. I normally use a greyscale height map to create a 3D terrain in external 3D software. I have a location where I only have access to a RGB ...
0
votes
0
answers
23
views
Open platform to visualised bathymetry LiDAR
I have point cloud data that I want to visualise on an open platform, which I can extend tools upon to investigate further.
I was wondering if any offer a visualisation like below, where the ...
- 49
0
votes
0
answers
33
views
Apply affine transformation to LiDAR .las file
I'am currently working on a project that use a Local Coordinate system, and I need to reproject the file to UTM WGS84, to be able to load it to qgis.
I have the formula and values to reproject the ...
0
votes
1
answer
32
views
Aligning separate datasets with different CRS in QGIS for the purposes of terrain modelling
I would like to develop a 3D model of a site located in Vermont, USA. I will be using the state's LiDAR dataset which I am pretty comfortable with. However, I need to coordinate this topographical ...
0
votes
0
answers
50
views
Combine DTM with hillshade in QGIS
I'm wondering if it is possible to combine a LiDAR generated DTM on a 1m Scale with a Hillshade DTM on a 0,25m Scale to improve the level of detail of the LiDAR DTM.
If possible how can this be done ...
0
votes
0
answers
24
views
LiDAR point cloud has no classfications [laspy], trying to classify and filter ground points
I have a .las file of data collected on a road, and I would like to get only the ground and points 'below' ground (potholes, other indentations, for example). However, when I load the data, it seems ...
- 1
0
votes
0
answers
41
views
Deriving contours from .las files
I am trying to derive different contour lines from my LiDAR data. I am running in to an interesting error though (see attached picture). Any idea on how to rectify this? Smoothing?
- 1
0
votes
1
answer
73
views
Point Cloud Processing Tools on MacOS
I am trying to access the native Point Cloud Processing tools, developed by Lutra Conslting and added to QGIS 3.32 (https://www.lutraconsulting.co.uk/blog/2023/05/30/pointcloud-qgis-processing/).
I ...
- 1
0
votes
2
answers
86
views
Visualizing LiDAR image
I am new to QGIS and I am using QGIS 3.22 on a Windows 10 OS.
After importing the .laz file into QGIS (with the "Add point cloud" command) I can only seea square whose boundaries are made of ...
- 1
2
votes
1
answer
86
views
Writing COPC is not supported - Laspy
I have a simple code
import laspy
las = laspy.read('data/segmented.las')
old_class = las.classification
las.classification = new_class
las.write('data/segmented_5.las')
But this gives an error
...
- 191
0
votes
0
answers
23
views
QGIS LAS Elevation profile outputs - include instensity, return, etc and access via python
When I run an elevation profile in the current Dev of QGIS I get the graph as expected but if I save to gpkg, it creates a point dataset to which I can then add the x and y but how do I get the ...
- 8,248
1
vote
1
answer
65
views
LiDAR DTM slope slope analysis with a twist. Calculate elevation changes of at least 10 feet within horizontal distance of 25 feet
I have raster DTM image of LiDAR data, mapped to Washington state plane north (US survey feet), where each pixel represents an elevation value in feet.
Generating a "slope map" which shows ...
- 21
1
vote
0
answers
33
views
How to augment LiDAR/DSM data from 3d models
For a viewshed analysis in QGIS 3.34, the I have LiDAR/DSM geotif files available. I want to modify/augment the DMS layer by adding the height information from 3d models of specific buildings. This ...
4
votes
1
answer
140
views
Automate LiDAR DEM feature extraction using R
Can the delineation of bowl-like depressional landforms be automated from a LiDAR TIFF using R?
library(terra)
fu <-system.file("path/to/the/data/provided/below.tif", package=&...
- 77
2
votes
0
answers
86
views
Doing simple manual classification of LAS using QGIS
Are there any basic tools for lidar classification in QGIS?
Id like to do simple function like reclassing single points, classing points inside a fence or above a line. something similar to the basic ...
- 29