Questions tagged [las]
An industry-standard binary file format that maintains information related to lidar data.
328
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Untwine error: Can't refer reader for a LAS file (Point Cloud File)
I was trying to import a las file to QGIS 3.28.12 Firenze. It really take me sometime to attempt to load the file but still failed to display all the points.
So I downloaded a point cloud file for a ...
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How to fill pits for a DEM/CHM when using the LAScatalog engine?
I'm trying to create a DEM/CHM using the LAScatalog engine. I've followed the steps in the lidRbook. In chapter 6 section 6.4 the post processing fills in areas no missing values for single las files ...
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Create a buffer on a single LAS file using lidR
I want to create a buffer for a single LAS file in order to test different algorithims for DTM creation on a small scale before scaling up to all my files using LAScatalog.
I know LAScatalog creates a ...
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Having trouble creating an ArcGIS Pro LAS dataset profile view like ArcMap
I am using ArcGIS Pro 3.1.3 and am looking for a way to view a slice of LiDAR data side-on, like the ArcMap LAS Dataset Profile Tool not rotated in 3d; I have 3d analyst and Advanced licenses.
I have ...
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R LidR Package readlas function with extra features limitations
I'm encountering an issue while working with LAS data generated from the open-source software CloudCompare. I've exported 24 geometric features to a LAS file format(1.4), and I'm experiencing ...
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Reclassify points in a LAS file using laspy
I am trying to change the classification of all points in my las file above a certain height (z value) from 2 (ground) to 1 (unclassified). I wrote the following code to do this:
las = laspy.read(&...
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Exporting .LAS file after using v.lidar.correction
Question
I want to use the GRASS GIS LIDAR modules (v.lidar.edgedetection, v.lidar.growing, and v.lidar.correction) to classify points for LAS files. I'm very new to working with databases, and the ...
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Laspy LAZ exported files with extra dimensions and QGIS name mangling
I'm writing a LAZ file with laspy, and I include some extra dimensions named bx, by, bz and b. They are all np.float64 (I used the version 1.4 and point format 3).
The file is properly created but ...
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PDAL mesh pipeline producing poor mesh results and losing precision
Intro:
What I want to do is:
read in a las file
crop the las around a specific point in space (probably using a radius)
generate a mesh with cropped points using poisson
The PDAL pipeline below ...
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40
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Issue converting .ply to LAS then LAS to COPC , losing colour information
Using PDAL to convert .ply file with colour information to LAS, I can verify I see the colour information in cloud compare.
However, when converting the LAS to COPC , I'm losing the colour information ...
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25
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Serve LAS/LAZ data from server to frontend
I have the following architecture:
Frontend: Vue3 w. OpenLayers7 (Typescript)
Backend: FastAPI (Python)
WebMapServer: GeoServer 2.23
I would like to display LAS/LAZ LIDAR data through Potree and I'd ...
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41
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How to derive first return points from a raw LAS data file
I have a raw (never classified) las dataset derived from UAV that I am attempting to obtain a DEM, DSM, and eventually CHM from. I have successfully been able to classify ground points and vegetation ...
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Removing trees from classified LiDAR based on polygon layer
I need to adjust the areas in a .las file where the trees and shrubs were cut last year.
There are basically 5 classes, with one class ("20") for taller vegetation.
Is there a simple ...
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Cannot join LAS file In QGIS with Whitebox Tools
I have 9 .las files that I am trying to join into a single .las file in QGis. I have been using Whitebox tools plugin in QGis and when I try to select all the files and assign an output file if get ...
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LAS files not identified in lidR
When I try to upload the las file to work on lidR package it give the following error.
The code I used to upload the file
las <-readLAS("<Sample.las>")
Error in streamLAS.character(...
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Assign (update) CRS for new created from npz file - LAZ file in Python
I need to create LAS/LAZ file from npz multidimensional array.
NPZ file contains 3 arrays inside array['wkt', 'data', 'max_min'].
array['data'] contains list of X, Y, Z - coordinates that used for ...
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QGIS 3.28 - 3.32 - Can not open .LAS-file format
I have multiple datasets of LAS-files, which I can not open in QGIS. I get an error stating LAYER is not supported or something like that.
I do, however, have files with an .ept extension in JSON-...
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44
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ArcPy filter and export LAS dataset
Building upon ArcPy IDW interpolation with LiDAR point cloud data, suppose I want to select certain classes in the las file and then export the final output in its original format (.las), how do I do ...
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QGIS 3.28 and LAStools issue - lasinfo not recognized as an internal or external command
I'm trying to run one of LAStools open source commands on a .laz file I have.
I have installed the plugin in QGIS v. 3.28, and have downloaded the LAStools-master folder available through GitHub (...
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35
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Computing normals option not working using CloudCompare GUI
I am trying to compute normals for a pointcloud I had cropped from a USGS lidar map. It is a .las file, but it might be missing some header values, but it does get imported into Cloud compare without ...
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41
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"Vertical and linear units in the X,Y, and Z coordinate systems are not the same" error in a task process
I am having a CS issue for my LASD dataset. I'm trying to run a tool in ArcGIS Pro that will analyze my LiDAR dataset (about 100 tiles) and create tree points based on the clustering of classified ...
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24
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Can LASD file be used as input in Classify Point Cloud Using Trained Model tool in ArcGIS Pro?
I have 400+ LAS files and also a LASD data set derived from all of them. The LAS files together are somewhere above 50GB in size. The LASD is only ~800 KB. I take it, then, that the LASD obviously ...
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187
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LiDAR LAS to DEM in QGIS 3.22 without LAStools
I'm using Ubuntu Linux and have installed QGIS 3.22 which has native support for LAS files. I think that LAStools is for MS Windows only?
I can load the LAS data and see a pretty image.
Next, I want ...
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78
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Rename LAS point cloud classification
I'm looking for a way to change a las classification name. Want to change class 64 unknown to class 64 Culvert.
How do I change the name of the las class? Is it best to do it within the LS header?
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93
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Getting the footprint of LAS file in QGIS
I can get the extent of a LAS file with:
#Create a pointcloudlayer
lasfile = r"C:\GIS\data\testdata\22D054_684_39_7575.laz"
pc = QgsPointCloudLayer(uri=lasfile, baseName="test", ...
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87
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Automated Object Boundary Detection in Raster Layers from LAS Point Cloud Classification in QGIS or Python
I have a raster layer generated from LAS point cloud classification, where pixel groups represent objects (e.g., rocks) detected above ground.
However, the classification is not perfect, and the ...
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22
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LidarJoin tool only processes 1 file, there is no join
New user here. I am trying to combine two .Las files into 1. I add the 2 las files into input box but it only outputs 1 of these files.there is no join. What am I doing wrong?
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Create 3D polygon of airspace above terrain
I have a LAS dataset of mainly vegetation and ground. I am looking to create 3D polygons in ArcGIS Pro that essentially fill in the space above the ground and flanked by the data (trees and bushes) to ...
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Output of Point Cloud Cropping using PDAL displaying as straight line
I am cropping my point cloud (.las) using PDAL, when i display my original point cloud it looks like this,
But after i crop it, the output looks like this, i.e. a straight line in viewer mode.
Here ...
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Is there a major drawback of working with compressed LAZ vs. the uncompressed LAS?
Compressed LAS pointclouds (LAZ) are significantly smaller than the uncompressed ones (I observe a compression factor of x4 - x5). Since point clouds are often large files, this is a substantial ...
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Improving building footprint polygons converted from LAS Point Statistics as Raster
I am following the ArcGIS PRO workflow to extract building footprints using Lidar Pointcloud data.
I am working with a Lidar dataset that has a spacing of 0.344 points/meter. I am using LAS Points ...
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327
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How to efficiently reproject a LAS point cloud to EPSG:2056 (not known by LAStools)?
I have a large LAS pointcloud in LV03 (EPSG:21781) that I want to reproject to LV95 (EPSG:2056). My approaches so far bear no fruit.
What is a good way to re-project LAS data to a different CRS (...
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249
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Why is laspy X,Y co-ordinate different to X,Y co-ordinate in lidr
I am working in both r and python to process lidar data with .las format. One thing I have noticed is that the x,y co-ordinate when working with laspy is different than x,y co-ordinate when using lidr....
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42
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TypeError attempting conversion of txt file to las pointcloud format using pandas & laspy
I'm following this guide - https://pointly.medium.com/how-to-convert-your-point-cloud-data-into-las-laz-434ada0f1e99
Attempting a conversion from a txt file to las
My bathymetry data is in following ...
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299
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QGIS Import Fails with Invalid Data Source Error Loading LAS file: "Global encoding WKT flag not set for point format 6 - 10." [duplicate]
I am trying to import some .las files in QGIS 3.28. I am successful with other files but for one file when I drag the file and drop it in the QGIS interface, it produces the following error:
Invalid ...
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32
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Error in ModelBuilder while all inputs are correct in the log
So I made a simple ModelBuilder to create a shapefile from a LAS dataset. Without the inline variables it is working correctly. As shown in the log, all the inputs are correctly taken and when ...
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225
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Render multiple COG files using OpenLayers
I am able to render a single COG (Cloud Optimized GeoTIFF) file using OpenLayers examples
But, when when I go for rendering of multiple COG files, then it gives error.
How can I render multiple COG ...
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46
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Some points are missing after using LAS classification and filtering points based on clarification and rewrite into a new file
I need to save .laz file that have only point cloud data corresponding to water classification. I used following code, it works. But it significantly reduce number of points from original file.
import ...
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169
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Convert LAS tool hangs at 2%
I'm trying to convert LiDAR data from .LAZ to .LAS using the Convert LAS tool in ArcGIS Pro, but it always stops at 2% and is never able to complete the decompression. Does anyone have any thoughts ...
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705
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How to open LAS files in Google Earth Pro
I have received LAS files and I would like to extract the GIS data and use it in Google Earth. Is there a way to open LAS files directly in Google Earth Pro, if not what are the steps to do that?
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lidR plot large LAS crashes RStudio
I'm trying to plot a large LAS (9GB, 269,671,586 points) using plot in the lidR library. (RStudio version 2022.07.2 Build 576, R version 4.2.2, lidR version 4.0.1)
I have plotted smaller LAS ...
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63
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Iterate las files to Add Surface Information
I'm trying to run 'Add Surface Information' to populate elevation data from 100s of las files to a polygon in Model Builder.
However it doesn't seem to matter whether I use Files or Datasets as an ...
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149
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Removing building data from LAS Dataset Layer in ArcGIS Pro to create tree canopy height layer [closed]
I'm working with various lasd files of an arboretum in order to create a layer with heights for the tree canopy. I'm trying to remove buildings from the LAS dataset so that the layer only reflects ...
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638
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Plotting LiDAR data with matplotlib
I am trying to plot a las file with one million points in Matplotlib. When I try to plot the file it always gives me a blank result.
This is the code I am using:
import numpy as np
import laspy
from ...
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81
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Labelling LiDAR points in Python
I am new working with LiDAR and have been assigned to label LiDAR points. I have no clue where to start. Is there any Python library that helps in this task?
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427
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PDAL filters reprojection is not changing Z values
I'm trying to reproject an LAS file using PDAL, and it looks like the X/Y values are being transformed, but the Z values are staying the same.
pdal translate input.las output.las -f filters....
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345
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Using ArcPy to iterate through multiple LAZ files and convert them to LAS files with lastools
I'm using Jupyter Notebooks in ArcGIS Pro and I would like to convert multiple .laz files into .las files by using the opensource toolbox 'lastools' and its function 'laszip'. For this I would like to ...
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95
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Merging .asc without conversion to GeoTIFF
I have a lot of LiDAR data in the format of .asc, however not all of the data is needed for my study area. To get just the data I want, I have merged the .asc files before clipping them with a mask ...
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165
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Filtering out points above maximum height minus 10 in LidR [closed]
I am trying to create a trunk density dataset by removing ground points and canopy points from a forest lidar dataset. My goal is to use the filter_poi tool to remove any points below 1.5 meters from ...
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3
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254
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Normalize height on a LAS catalog stops processing without an error message
I'm using the lidR package 4.0.1 in R to normalize height on a las catalog. I'm using a raster DTM as the elevation source. I have successfully completed this task using the same script and same ...
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