Questions tagged [point-cloud]
A point cloud is an unstructured set of points, each defined by x,y,z co-ordinates.
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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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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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Filter just the last return from a point cloud
At 3.32.3, the Processing Toolbox > Point cloud extraction > Filter tool does not include the ability to select only the last return in its list of filter expressions.
This functionality is ...
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Geolocating a PCD
I have some simulation software that generates values in real 3D space. Because the output is in real space, it's being stored in the LAS format. However, LAS is not really designed to store arbitrary ...
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PDAL translation seems to be causing a scaling
I'm trying to georeference a .laz pointcloud in order to correctly show it in QGIS on a map. I notice however that while using the pdal transformation, there is a change in the scale of the point ...
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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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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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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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Merging Multiple 3D Point Clouds, Reducing Misalignment and Correcting Unusual Height
I've been trying to merge two point clouds into a single uniform point cloud using the Python package pyvista. However, I have encountered an issue that the misalignment between these two point clouds ...
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Apply custom vertical datum transformations to point cloud
My goal is to write a script that can add the geoidal undulations contained in a TIFF file (local geoid model) to a point cloud. I wrote the script below in Python that should perform this task using ...
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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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Create multiband raster from .las file using PDAL
I am quite new to creating rasters from point cloud (.las) files. Basically, I would like to use PDAL and its writers.gdal stage to write a raster with two bands.
The first band should be written ...
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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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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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Classify Pointcloud using thematic layer with lidR
I want to use lidR to classify points within a point cloud using a few thematic shapefiles. This includes buildings, vegetation and cars. For this I use the classify_poi function, which works for ...
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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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How to speed up my PDAL pipeline script?
I'm creating an app for point cloud processing. I've made a pdal script with Python and I have some trouble with the cpu usage and processing speed I've made a pipeline for las processing, with some ...
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Point Cloud Processing algorithm for QGIS 3.30
Has anyone installed the new Point Cloud processing capability in QGIS that was announced recently? Apparently it is in the Github Master but I am not sure how to do this.
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How to combine ortho imagery and a DSM to make a pointcloud
I can create a VRT with four rasters and convert this to GTiff. But I don't seem to be able to create the point cloud from the GTiff. I have tried:
pdal translate input.tif output.las --reader gdal
...
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Can you force a feature count update for existing points layers, after adding points to the underlying file?
I have been working with Point files, adding and subtracting points, and although the existing layers are pointed to the file I am modifying, I cannot get the new feature count to reflect in them.
The ...
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Editing Scene using ArcGIS Pro
I'm working in scene (ArcGIS Pro), with a point cloud and a shapefile. This shapefile (points) has its x,y,z coordinates and I would like to drag these points and place them in a specific position, ...
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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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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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How to calculate the distance between multiple points from two layers
I have these two layers (see the picture) that contain point clouds from a radar measurement processing result. I have got to check if the layer in green (from this month) is aligned with the layer in ...
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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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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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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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Convert colorized point cloud to colored raster
Most of the tools that that I have seen convert a point cloud to a DEM. I am more interested in a GeoTiff that looks like a satellite imagery rather than an elevation map. What tool do I use to do ...
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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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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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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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Is there any way to identify what does the value in point cloud text file represent without contacting the one who generated it?
I have a point cloud text file that I obtained from the internet and it contain 6 type of value. I assume the first three value represent xyz values but I do not know about what the other three ...
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lidR: "Argument is not a LAS object" when using catalog_apply
I am using the lidR package to read lidar data (LAZ format), then using clip_roi() and normalize_height() to process the data for the segment trees function. These functions are being executed within ...
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QGIS layer properties window oversized
With the latest version of QGIS (3.28.2) with Windows 64 bits, with the new point cloud layer: the layer properties window is oversized in the height. This hides the bottom buttons (OK, Cancel...), ...
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Remove point cloud overlapping flight line with a Python script
I have a LiDAR file (.las) corresponding to a topographical survey that I was able to carry out. However on this file we can see an overlap of points due to the percentage of flight overlap for the ...
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Point cloud export
I have a point cloud file (*.laz) and when I import it to QGIS I get 5 sublayers. I want to export just the sublayer that is called ground to DXF (AutoCAD), but can't manage to do it. When I export it ...
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How to limit memory usage for pdal to import LiDAR data
While trying to import LiDAR pointcloud data in .las format (my file is 38GB) to PostgreSQL using the pointcloud extension, I keep getting Killed after several minutes of the following command running ...
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Point cloud is decreasing when adding in QGIS
I have a point cloud with coordinate information from Agisoft metashape software and I make the point clouds into the WGS84 coordinate system at Agisoft. But when I try to use the point cloud in QGIS ...
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Export LAS file to XYZ and retain RGB values
I am currently trying to import LAZ LIDAR data into ArchiCAD (a 3D modeling software) for an architectural project. Using QGIS 3.22.11 and LAStools las2txt I have successfully exported the LAZ file as ...
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How do LiDAR and photogrammetry DTMs differ?
Recently, I received two temporally distinct DTMs of a particular area processed with photogrammetry. The datasets were acquired about one year apart and no landscaping activity occurred at the site ...
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Calculating the outer boundary of point clouds and export it as shapefile
I want to calculate the outer boundary of bunch of point clouds.
Going through different answers from stack I made this messy kind of solution, which works but is insanely slow. for 208 files(~117gb) ...
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How to visualize the labels from a Point Cloud in QGIS?
I have a point Cloud (Las file) and I wolud like to see/visualize the labels (Z values).
There´s a way to do it in QGIS? (I´m using QGIS version = 3.24)
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Crop a large point cloud with GeoJSON defining the geometries of sub point cloud
I have a large point cloud (a city model) and would like to get the point clouds of every building in the city. I already have the GeoJSON file with the geometries of every single building in the city....
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Potree : Save user interactions
I am a new user of Potree and I would like to know if anyone has already an idea or found a way to save a user's interactions on Potree and use them again.
For example: if the user added an annotation ...
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Python: how to filter a point cloud according to the color of the points
I have a point cloud with XYZRGB data which was derived from images. Is there any way I can filter the point cloud based on colour data? This is possible in images maybe using OpenCV or some other ...
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Ideas to cluster lanes using color information
My point cloud consists of XYZ values and for each xyz there is corresponding color (RGB) value. I don't have any other information in my data eg:intensity, classification etc., as this point cloud ...
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Pointcloud to RGB raster (orthomosaic)
I am trying to create an orthomosaic for as cheap as possible. The project I am working on has absolutely no budget and the methods I use need to be easily used by someone who has no experience in GIS/...
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