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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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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Convert 3D vector points to LAS data for use in QGIS
I have a vector layer of points with 3D coordinates and one numerical category attribute. I would like to convert these to a LAS-file which can be visualised in QGIS with the attribute as a component ...
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Strange behaviour in Z Cartesian axis when creating 3D Point Cloud
I'm working on a tool to convert SRTM data to Cesium 3D Tileset Point Cloud.
All is working fine as you see here:
And in this video ( subtitle in portuguese): https://youtu.be/zroGesdS-OI
Well... My ...
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pixel_metrics - compute selected metrics only
Below is the code to compute all standard metrics from R package lidR.
library(lidR)
x <- pixel_metrics(las_catalog, .stdmetrics, res = 30)
I want to compute only few pixel metrics only, like :
...
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Options for making a DEM of single-return point cloud?
I have a project site surveyed with single return photogrammetry so, all points are unclassified. It was not a problem to create a DSM of this data, but I also need a DTM.
What are my options? Will I ...
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Are RGB values encoded/recorded in raw LAS/pointcloud data?
RGB info in the pointcloud: Is this always from a post-processing step (e.g. using imagery overlay techniques to do so) or does it in some cases come from the machine/sensor which recorded the LAS?
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Determining pixel size based on LiDAR point cloud density
I have a point cloud with a density of 8 points/m². I would like to generate a digital elevation model (DEM) from it, but I don't know what resolution to set as the raster pixel.
So I would like to ...
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Ideal procedure to deal with faulty data for generation of LiDAR trajectory [closed]
The reason for this post is to understand possible remedial measures when one is dealing with a lidar dataset that is faulty (incorrectly populated, missing trajectory information etc.). Obviously, re-...
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Reclassify points within a bounding box with PDAL
I have a list of 3D bounding boxes manually drawn around noise points and I want to reclassify them as noise. One option would be to simply drop them but, in this particular case, I would want to have ...
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Attribute/dimension adding to the lasfile
.LAS files have different dimensions as x, y, z, etc. Suppose, I want to add another dimension with the name "n". How to do it correctly? I attempted to use the following pdal pipeline:
...
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Highest LiDAR point return per sq m?
I currently have at my disposal QGIS and Trimble Business Center.
I am looking for semi-automated solution for extracting the single highest lidar point return per square meter. My area of interest is ...
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QGIS point cluster correlation
Is there a way to (preferably in QGIS that I actually can use) analyze two sets of point layers and describe the correlation in the espective cummulations?
For instance, I have points that experts ...
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TPI calculation by PDAL [closed]
Is there a convenient way to calculate the topographic position index by PDAL?
I have LAS file and what I do is iteratively for every point calculate the TPI. The coordinate information I take from ...
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Big .las to raster converting by writers.gdal
I have a script:
pipeline = [
path,
{
"filename": out_path,
"gdaldriver": "GTiff",
"resolution": 1,
"output_type": "max",
...
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Assigning a CRS to a LAS
Is there a way to assign CRS to the LAS file through Python if the name of CRS is corrupted and looks like following?
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Incorrect CRS affects on writers.gdal result
I have a .las file with CRS that is not decoded correctly and looks like following:
At the same time the part of metadata which (as I understand) stands for CRS looks like this:
"...
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How to invert LAS files
I have a bunch of LAS files which are supposed to show data underwater but the depth (z) is poisitive rather than negative so they are inverted. I'm looking for the fastest way to invert/flip them on ...
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Which options should I use when creating textures for better buildings quality Agisoft?
I am new to Agisoft and I created a 3D module. The textures of the buildings don't look that good. I would like to know which options should I use in the Build Texture tab to make it better.
Or maybe ...
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writers.gdal wrong pixel size
I want to convert the .las file into .tif by the following pipeline:
pipeline = [
input_path,
{
"type": "writers.gdal",
"...
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filters.delaunay doesn't work
I have pdal 2.2.0
My pipeline is the following:
pipeline = [
input_path,
{
"type": "filters.elm"
},
{
"type": &...
2
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1
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Viewing LiDAR datasets at lower zoom levels in ArcGIS Pro
Is there a way to display LiDAR datasets at lower zoom levels in ArcGIS Pro?
Currently, I can only see the point cloud at a zoom of around 1:800.
What I would like: view the point cloud/LiDAR dataset ...
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Add voxel attributes to LAS point cloud
I would like to add data from voxels to a point cloud. Imagine I calculated some voxel statistics with voxel_metrics(), for example:
voxels <- voxel_metrics(las, length(X), res=0.1, all_voxels=TRUE)...
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Point cloud data on a grid
I have a point database marking different locations (presence of an animal) on a grid of 250 m x 250 m over a certain period of time. Each one of these points have a date.
By intersecting the grid ...
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132
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Calculating grid_metrics() in a loop, using column name within variable
I want to calculate grid_metrics() for several fields of my point cloud, using several functions. I want to perform this in loops to make my code look cleaner.
Basically I want this:
# loop through ...
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132
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Get eigenvalues of large point cloud using lidR
I have some very big TLS point clouds (up to 400 million points) and want to assign the eigenvalues to each point in order to later calculate geometric features like planarity or sphericity. I use R ...
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pdal truncating values when writing ply
When using pdal to either translate to ply file or split a ply file in smaller chunks, it appears to be truncating values so I end up with point clouds with stripping. This does not occur with other ...
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Extracting trees/vegetation as separate point cloud using ArcGIS Pro
I have ArcGIS Pro 2.4 with 3D Analyst and Spatial Analyst Extensions. I would like to extract all points from a point cloud (.las) file that match a certain classification to a new, separate point ...
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QGIS point clouds: hide flat pane in 3D view
After successfully loading .laz point cloud data to QGIS 3.18 on Win 10, I am able to show the data in 3D view. However, the data is visualized twice: once as a flat pane with the same symbolization ...
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Open .laz point clouds not available in QGIS 3.18
The recent release of QGIS 3.18 supports point cloud data. As can be seen on the screenshot in the linked Visual Changelog (above), .laz files should be supported.
However, in my installation on ...
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Obtaining city model for modification in CityEngine from LiDAR point cloud
In ArcMap I transformed the point cloud into Multipoints and then into Singlepoints and I obtained this model in ArcScene.
Is it possible to transform these points into 3D objects?
Finally, I would ...
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How to get VLRs from a .las file with laspy
I have a .las point cloud data file that I am trying to get the vlr data from. I have found this link - Update EVLR header info for .LAS file using laspy and have read the docs on Laspy - https://...
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FME SherbandGeneralizer - estimate time for "Optimizing Memory usage"
I have a workspace with a pointcloud of 240.000.000 points as input, goal is generalized countour lines, that do not intersect each other.
The workspace mainly consists of (cp. screenshot)
...
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Combine LiDAR data with OpenStreetMap
I have already built Ubuntu for OpenStreetMap and I have some LiDAR data file in LAS/LAZ format. Is it possible to make LiDAR data appear in 2D and be a part of OpenStreetMap? If it is, how?
I have ...
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Getting LiDAR point cloud point spacing using PDAL
I am trying to use PDAL (in Python) to extract metadata from a LiDAR point cloud (.las). I am using the "pdal info" command and applying different flags (e.g. -metadata, -stats) to get ...
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Finding the minimum spanning tree (MST)
I have a set of points at which I want to find the minimum spanning tree with PostGIS. I have no lines between them, I only have the starting point from which to start building the tree (the ...
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Extract vertical planes from Point cloud
I am looking for a tool/method for extraction of vertical planes (building facades, fences, ...) from mobile mapping point clouds.
There is software (Cloud compare e.g.) that offers RANSAC plane ...
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Creating buffer around points belonging to object using lidR
I would like to create a 3D buffer around powerlines inside a LAS file that contains forest and power lines in lidR (R package). If I would manually delineate the line features and export to an ...
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lidR: Save LAS files from a clip_roi list
I have clipped a point cloud with a shapefile containing multiple polygons, using clip_roi() function. The result is a list of LAS files. However, when I try to loop through the list and save each ...
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Comparing two point clouds, one in WGS84 and the other in ECEF
I'm really a newbie and this task seems over my head. Suppose you have one cloud from LiDAR (a LAS file) with coordinates in WGS84 and another cloud, obtained from structure-from-motion, in ECEF. They ...
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arcgis.learn show_batch() index error and lr_find() runtime error while using pointcnn for LiDAR segmentation
I am trying to segment vegetation from LiDAR point cloud using PointCNN on Jupyter notebook. But I am getting Index Error on running show_batch() and runtime error on running lr_find() while using ...
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How to improve LiDAR classification in GlobalMapper
I have a LiDAR point cloud that has a density of 16.4 points per m^2 and spacing of 0.2469m, and am trying to extract trees from it but the classification came with a lot of messy points in classes ...
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Cesium | Any Alternatives to 3dtilesets to visualize point cloud data?
I'm in the early stages of developing a web-based visualization for multiple GIS data sources (imagery, vector data sets, terrain, point cloud...etc). I am using the Cesium javascript library for ...
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Subset a lascatalog point cloud within a function while calculating grid_metrics
I am trying to create subsets of a point cloud based on the ScanAngleRank and compute some metrics for each subset. Then return a stack of values(rasters) for the metric. I modified the rumple index ...
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Separating ("high enough") trees from "lower height" vegetation? In abstract (non-RGB) .xyz point cloud
Suppose I want to select trees that are "high enough", but the data contains other vegetation, like bushes and smaller trees.
My data is abstract (non-RGB) .xyz point cloud. I.e. there's only ...
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pdal: why does filters.hag and filters.ferry with HeightAboveGround=Z reset original points to Z=0?
pdal: why does filters.hag and filters.ferry with HeightAboveGround=Z reset original points to Z=0?
I'm essentially trying out the example-3, given here:
https://pdal.io/stages/filters.hag.html#...
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Applying machine learning methods in orfeo toolbox into DEM raster
I would like to apply machine learning methods in orfeo toolbox to classify some landscape features such as shrub and coarse woody debris in woodland. I created DEM raster image from very dense ground ...
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Using function lasdetectshape of lidR
I would like to try "lasdetectshape" in lidR package to detect line pattern objects in my point cloud.
library(lidR)
las <- readLAS("9a-1.las", select = 'xyzicnrRGB')
las <- lasdetectshape(las,...
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