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.
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Iterating through las directory using lidR in R results in not finding file or not recognising file as .las
I am trying to produce a script which has functions that can produce a list of statistics and writes them to data.frame, which can in turn be written to a csv file if needed. This would be to check ...
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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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Plotting real (normalized) las values on dtm
I am trying to plot a las where I filtered objects, that have a first and a last return simultaneously (objects in the las file), onto a created dtm of the same las. I am able to produce a good result....
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Products on the market that are capable of determining wireless radio line of sight [closed]
I'm looking for a product that maybe uses like Google Earth as a base, that has digital elevation data for every building and tree like Google Earth does, where I can place a tower.
The program should ...
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Large geospatial data (LiDAR, hyperspectral, etc.) delivery applications [closed]
I'm relatively new to the geospatial world and trying to understand the best methods for delivering customer data through the web. We've used FTP in the past and I know some folks will use ArcGIS ...
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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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Rasterization percentile of LiDAR file in open source
I am trying to rasterize several LAS files inside a Python loop. The output that I am attempting to achieve is a percentile of the distribution of normalized heights within each cell of the raster.
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How to classify points in LAStools using shapefiles as reference
I am new to LAStools, and mostly use MicroStation/Terra for classifications, except MS is a resource heavy at times so can be slow and can crash. The macro we run uses shapefiles as a reference, and ...
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Finding/highlighting significant elevation change
I am quite new to QGIS, so pardon if I use the wrong terminology etc.
I am scouting terrain to find new bouldering/climbing locations. My goal is to find significant elevation differences and ...
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How to have a good rendering with mdenoise - DTM LiDAR denoising
I'm trying to generate a clean slope map from a LiDAR DTM. Due to LiDAR high resolution, the slope map is full of noise.
So to do this, I use mdenoise library.
It works quite well but it generates ...
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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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PDAL readers.ept fails to save LAS file
I am attempting to access the USGS 3DEP LiDAR Point Clouds - Registry of Open Data on AWS via the EPT PDAL reader in Python. I normally work with Python notation, so my code looks like this:
extent = ...
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PDAL merging multiple LAZ files from folder in Python
I am attempting to merge multiple laz files stored in a specific directory. I have seen in the PDAL documentation that PDAL doesn’t handle matching multiple file inputs except for glob handling for ...
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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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Extract complex roofshapes from LiDAR
I've been using the 3D Basemaps Solution on the ESRI Solutions page (I no longer see it listed) for a little over a year now with ArcGIS Pro with mixed but improving results to create scenery for use ...
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Matterport E57 file
What CLI tools can I used to convert e57 to pcd/obj files?
I am trying to show my users the 3d representation of a scanned building taken by a lidar camera on a map, I think version 3 camera, I don't ...
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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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Clipping LiDAR Data to Map Data w/ LAStools bounding boxes have no overlap
I am trying to clip a series of LiDAR .las files with the lasclip64 tool in LAStools. The area I am trying to clip is Prospect Park in Brooklyn, NY. I have retrieved the .shp file for this area from ...
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Computing grid cell statistics using LiDAR point cloud in QGIS
I have a LIDAR data .laz file of a DEM and a cell grid vector file. I want to compute grid cell statistics, like mean and variance using the LiDAR data. How can I do this in QGIS?
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ArcPy IDW interpolation with LiDAR point cloud data
There are several questions such as 1, 2 etc on interpolation, but, when I implement the same procedure to calculate digital terrain model from point cloud I get an error:
las_path = r"C:\Users\...
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Euclidean distance point Cloud clustering in R lidR
I'm looking for a way to implement the python function filter.clusters from the pdal package in R using the lidR package.
The function clusters pointclouds using the Euclidean distance, a tolerance ...
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Classify vegetation by height
Trying to further classify a las catalog that already has buildings, bridges, noise and ground classified. I want to break the unassigned points into vegetation classes by height but can't get it to ...
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Downsample pointclouds from USGS (.LAZ) files in Python
I am trying to process pointclouds from USGS for a project and I am having a hard time working with the data (.LAZ files) because they are very large. They have around 36 million points. I tried ...
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How to clip USGS LiDAR data and polygon files
Am kind of new to the whole Geo Info systems, I am trying to clip USGS lidar data which is (.laz) format using polygons in a (.shp) file. I am using Python 3.10: with packages laspy, geopandas. I use ...
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LiDAR data processing - Which is best Python or R? [closed]
I have started working with LiDAR data processing recently. I looked up for libraries to work with LiDAR in Python and R. I would like to know which one has better libraries and extensive ...
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WhiteBox tools error 'Incorrect parameter value for inputs' when running 'LidarJoin' tool
I have 130 LAZ files I want to join into 10 or so files to make a DEM, these are all bare earth, I'm attempting to use the LidarJoin tool from WhiteBox tools, and I get an error upon running: '...
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Filtering LiDAR points by elevation/height
I am trying to prepare training data for a deep learning model. The objective is to be able to identify trees in an urban area. Properly classifying the points in my training data would be a lot ...
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Esri deep learning model is not particularly effective
I am using Esri's tree classification deep learning model, in conjunction with the Classify Point Cloud Using Trained Model tool, to classify LiDAR point cloud data in an effort to develop a tree ...
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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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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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Write classification to raster for highest object in LiDAR point cloud
What we want to do is rasterize the classification value of the highest point (in the Z dimension) in every pixel. Basically we are trying to mimic optical imagery where whatever is on top is what is ...
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available data (DSM FIRST, DSM LAST, DTM, BUILDING FOOTPRINT) how to obtain buildings heights?
Lidar data: DSM (First/last) AND DTM are in.ASCII format
Footprint available extracted from OpenStreetMap.
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Python code LiDAR to 3D building footprint
I'm trying to extrapolate a 3D building footprint from a LAS file in ArcGIS Pro . As I understand it the process is filtering the LAS points, classifying the ground and non-ground points, creating a ...
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Plotting CALIPSO data in R
I am trying to plot one subdataset of CALIPSO which is in hdf format using R. The data is totally new to me as it's LiDAR data. I am not able to understand how to plot a graph between backscatter ...
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How to efficiently deal with LAS tile overlap when 'Classify LAS Overlap' takes days
I am using the tool 'Classify LAS Overlap' in ArcGIS Pro to classify overlap points in LIDAR data from multiple sources (data from Colorado Hazard Mapping) in order to eventually turn them into a ...
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USGS Nationalmap API giving error for certain bbox and polygons
I am using USGS national map API (https://tnmaccess.nationalmap.gov/api/v1/products) to search for Lidar data.
But for certain bbox and polygon this API is giving me error.
Example: https://tnmaccess....
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How to correct PDAL error using filters.smrf "Some NumberOfReturns or ReturnNumber values were zero but not all..."
I'm new to using the PDAL system to query and process LiDAR point cloud data from the USGS Lidar Explorer. I've been following some of the tutorials in the PDAL Quickstart Guide and have applied the ...
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Plotting Mean High Water Mark from DEM LiDAR around mangrove vegetation
I am currently trying to plot a Mean High Water Mark (MHWM) using a 1m DEM created from LiDAR. I have been able to plot a contour value representing MWHM based on tide gauge data. When I create the ...
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Cannot rotate angle of LAS dataset using spTransform
I previously was able to adjust the angle of my las data using the below function I made. No idea why it has started giving issues? Has spTransform changed?
I am using the code below in R:
rotatelas &...
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DEM derived from LiDAR in wrong location
I am trying to derive slope and aspect from a DEM that was derived over a mine using LiDAR in ArcMap v 10.8.1 . However, the DEM seems to be in the wrong location (further North from the Area of ...
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How to average a point cloud object groups to a single centroid point?
I have a point cloud data. What I want to do is count how many objects are there in the point cloud.
Suppose there are many cylindrical objects in my point cloud. What I am thinking of doing is to ...
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lidR custom grid metric returning raster output mean max values lower than 1 m for mean height bin interval between 0.2-4
I want to calculate the mean height of shrubs layer using the mean height of points between 0.2-4 m above ground but the raster output mean max values never is higher than 1 m which is not make sense ...
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Converting GEDI HDF5 LiDAR data to a format readable in GIS
Based on this code here
that converts .h5 format into a shapefile, where 'all_samples_sum' feature was replaced with 'digital_elevation_model'. The code I used is based on this code. The error ...
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QGIS sample data from LiDAR raster layer
I'm trying to pull data from the Scottish open data LiDAR information (https://remotesensingdata.gov.scot/data#/list) and I can use the Identify Features tool to click on a point and get the elevation ...
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Keypoint generation in 3D point clouds with Deep Learning
I have a huge dataset of 3D point clouds (each point consists of X,Y,Z coordinates) and another dataset with keypoints (also X,Y,Z) which lie on quite recognizable structures in the point cloud. As a ...
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Most detailed surface map that can be produced from LiDAR data in ArcMap
I want to find old military trenches or at least to get an idea where they were, so that I can go to those areas and survey them.
I know the basic method of conversion from .lasd to elevation raster ...
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Runtime error while executing pdal pipeline in VScode
I'm trying to solve a problem that I found using PDAL on visual studio code, but I'm stuck and I don't really get where the problem is from.
Few months ago I was able to execute python script on ...
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Error in "writeOGR" When creating a shapefile from convex hulls
I am working on the segmentation of crown canopy using LiDAR. I want to extract the crowns created after the segmentation as a shapefile. Other documentation and links show that using writeOGR I can ...
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lidR: Clipping LAS files with a polygon shapefile using clip_roi
I'm trying to clip a LAScatalog (containing several .las files) with a shapefile (containing multiple polygons). I tried using clip_roi function, however getting an Error: Z only allowed for 3 or ...
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Add Feature Based on Selection from a Reference Layer
I have a reference grid with 11,525 features that references a repository of the same number of lidar rasters. Repository is currently a separate drive, but the location can be wherever I need it to ...
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