Hot answers tagged

26 votes
Accepted

numpy array to GTiff using rasterio without source raster

This ended up being more straightforward than I thought, with all of the capabilities lying in the rasterio.open function. Here is an example using a proj4 string instead of wkt. import rasterio ...
user avatar
  • 1,024
22 votes
Accepted

Viewing LiDAR data from web browser?

I'm a little late to the party but here is another suggestion: http://potree.org/ It's an open souce, WebGL based point cloud viewer I've been working on for quite a while. == UPDATE == It can ...
user avatar
  • 473
20 votes

What are LiDAR returns?

ESRI has a pretty good help section on LiDAR (below). For more formal details on LiDAR, I would recommend the following books: Topographic Laser Ranging and Scanning: Principles and Processing ...
user avatar
  • 50.2k
20 votes

QGIS 2.14.1 LAStools install error: "wrong value for parameter 'Msys folder'..."

According to Diego Alonso's comments from the mappingGIS blog1, this error is related to QGIS version 2.14. With the upgrade, the standalone installer eliminated the msys folder from GRASS 7 ...
user avatar
  • 9,789
19 votes

Viewing LIDAR data (.las) in QGIS?

QGIS 3.18+ supports point cloud visualisation natively.
user avatar
  • 1,028
19 votes
Accepted

Seeking point cloud (LiDAR) data?

I decided to merge other answers with mine and organize them into a tabular format. I think it is easier to read and manage for future visitors: The table can be accessed from the following link in ...
19 votes
Accepted

Convert hdf5 LiDAR data (from GEDI) to LAS or LAZ

It's not possible to convert GEDI .h5 file to LAS file as including all data. Because .h5 file includes a lot of information about a point (actually it is a window in GEDI .h5 format, not a point). ...
user avatar
16 votes

Determining bare earth DEM from unclassified LAS file?

Generating LiDAR DEMs from unclassified point clouds with: MCC-LIDAR - Multiscale Curvature Classification (MCC) algorithm. (supports LAS versions 1.1 to 1.3) MCC-LIDAR is a command-line tool ...
user avatar
  • 9,789
15 votes
Accepted

Benefits of *.las vs *.xyz or *.ascii when working with LiDAR in ArcGIS for Desktop?

ArcGis has a new LiDAR dataset at 10.1 which will allow you to view your LiDAR data directly and also see more information than what's in a raster... for example you can add to ArcMap and then filter ...
user avatar
14 votes
Accepted

Converting LAS 1.4 to 1.2

For converting to las 1.2 from las 1.4, PDAL's translate command is an option: pdal translate --writers.las.minor_version=2 input-las14.las output-las12.las LAStools can also do the job: las2las -i ...
user avatar
13 votes
Accepted

Reprojecting LiDAR data with libLAS, error: "latitude or longitude exceeded limits"?

Set the scaling and offset when reprojecting to WGS84, e.g.: las2las --a_srs EPSG:26911 --t_srs EPSG:4326 -i file1.las -o output.las --scaling 1e-7 1e-7 0.01 --offset <something close to your data'...
user avatar
13 votes

Thinning large LiDAR point cloud?

It sounds like you want either a voxel-based thinning or maybe a Poisson-based one. PDAL can do either. See PDAL's tutorial on the topic at https://pdal.io/tutorial/sampling/index.html . As far as ...
user avatar
12 votes
Accepted

Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?

Have you consider to use GRASS GIS analysis? I have expirience that GRASS algorithms have very good accurance on hydrology analysis. For example, I want to generate something like drainage network on ...
user avatar
  • 1,743
12 votes
Accepted

Cleaning blocks pattern from urban LIDAR (blocks uplifted from streets)

If you are open to using alternative software to solve your problem, then I can suggest the Remove Off-Terrain Objects tool of the cross-platform open-source GIS Whitebox Geospatial Analysis Tools (of ...
user avatar
  • 10.8k
12 votes

Difference between LAStools, libLAS and PDAL?

The answer by Howard Butler pretty much sums it up. Some more background. When I created the first LAStools and the LASlib library that the tools are build upon I was a postdoc at UC Berkeley and ...
user avatar
  • 1,114
12 votes
Accepted

LAStools plugin in QGIS: ''The system cannot find the path specified."

Be aware one needs to have the LAStools plugin installed, but also the software per se. The LAStools plugin description says: ... . You also need to download the LAStools software from http://...
user avatar
  • 9,789
11 votes

Working with LiDAR data using other than Esri software?

I develop an open-source GIS called Whitebox Geospatial Analysis Tools that can be used to perform a range of tasks geared towards processing LiDAR data. It works with the popular LAS file format as ...
11 votes

What LiDAR processing tools are available in Python?

I have recently released an open-source (MIT) stand-alone (i.e. no dependencies) library called WhiteboxTools for performing many types of geospatial analysis, including LiDAR data processing. The ...
user avatar
  • 10.8k
11 votes

Removing pixel values below 0 in Digital Elevation Model in ArcGIS for Desktop?

You can use tool Raster Calculator. Then type this expression: SetNull("raster_name"<0, "raster_name") Choose output and you should create new raster with elevation 0-n.
user avatar
  • 6,386
11 votes
Accepted

Extracting tree crown areas from remote sensing data (visual images and LiDAR)

There is a considerable body of literature on individual crown detection in spectral and lidar data. Methods wise, perhaps start with: Falkowski, M.J., A.M.S. Smith, P.E. Gessler, A.T. Hudak, L.A. ...
user avatar
11 votes
Accepted

Assigning RGB values from Geotiff image to LiDAR data, using R

Thank you for clarifying your question as it was previously quite unclear. You can read a multiband raster using the stack or brick function in the raster package and assign the associated RGB values ...
user avatar
11 votes

Benefits of *.las vs *.xyz or *.ascii when working with LiDAR in ArcGIS for Desktop?

If you have the opportunity to get LAS or LAZ instead of TXT ... absolutely go for it. It will be trivial for you to go from LAS or LAZ to TXT (for example with the free and open source las2txt tool ...
user avatar
  • 1,114
10 votes

Working with LiDAR data using other than Esri software?

Since this is being linked to by https://gis.stackexchange.com/questions/132591 (since deleted) I'll add my own two cents with some more free and open-source tools. First, for command-line/batch ...
10 votes
Accepted

Account for bridge overpasses in a ground DEM to allow for water flow under the overpass

Martin is correct that while your workflow will do well for a specific user case, it doesn't account for many of the issues that road embankments create for flowpath modelling using fine-resolution ...
user avatar
  • 10.8k
10 votes

Filtering out canopies and buildings from DSM to have a bare earth elevation

If you have a raster DEM already, then there is a tool that I developed in Whitebox Geospatial Analysis Tools called Remove Off-Terrain Objects, contained within the LiDAR toolbox, that works well for ...
user avatar
  • 10.8k
10 votes

What are LiDAR returns?

The picture below from Fernandez-Diaz (2011) might help complementing Aaron's answer. Lidar returns are discrete observations* recorded when a laser pulse is intercepted and reflected by targets. ...
user avatar
  • 9,789
9 votes

LiDAR data density, returns per square meter

I develop a free and open-source GIS called Whitebox Geospatial Analysis Tools (can be downloaded here) that has extensive analysis functionality for processing LiDAR data. Whitebox contains a tool ...
user avatar
  • 10.8k
9 votes

Creating DEM from geoTIFF or asciiGRID LiDAR data?

You already have a DEM; there is no need for you to create one. The DEM is contained within your files, i.e. you have two copies of the DEM, one contained within an ArcGIS ASCII raster and the other ...
user avatar
  • 10.8k
9 votes
Accepted

Use laspy to create las file from scratch without opening an existing las file first

Rather than setting the entire points array in one go, try setting each dimension in turn: import laspy header = laspy.header.Header() outfile = laspy.file.File("output.las", mode="w", header=header)...
user avatar
9 votes

Converting between coordinate systems for LAS file using LASPY

You should check what the scale and offset are for your file. This can be done as follows: van_taken.header.scale van_taken.header.offset This almost looks like an overflow error to me. The lower ...
user avatar

Only top scored, non community-wiki answers of a minimum length are eligible