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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3
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1answer
269 views

Displaying LiDAR data with too many points in ArcMap?

I have imported LiDAR data into ArcMap in the shape of a Las DataSet with twelve .las files (contains over 100 million data points). I believe the file itself is working properly. However, no points ...
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0answers
135 views

Create laspy file object without creating a new file

I would like to create a new laspy.file.File object in memory without having to create a reference .las file. The basic procedure is read sample.las clip sample.las by converting the x and y ...
5
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1answer
174 views

Fixing spikes in DSM from LiDAR?

I have a DSM derived from drone LiDAR that I want to use as a base to drape imagery and, paired with a DTM, as a basis for estimating canopy height/volume. Unfortunately, the DSM has has many "spikes"...
7
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2answers
2k views

How to de-noise a DSM?

I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any ...
8
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3answers
4k views

Normalizing point cloud data

How I can get Digital Height Model (only object heights, DSM - DTM = DHM)? Many applications can do this, but they convert it to GRID or TIN format. I was wondering if it was possible to keep the ...
2
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2answers
239 views

Interpolating LiDAR scattered ground data?

I wonder if someone can give me a hint on how to interpolate sparse data. I have a 1km by 1km tile located in a dense rain forest area. Original LiDAR data are 37,395,021 points. I have played with ...
1
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1answer
491 views

Generating Canopy Height Model (CHM) with Quick Terrain Modeler?

I currently looking forward to process LiDAR point clouds (forest data) using Quick Terrain Modeler (QTM), but is it possible to create Canopy Height Model directly using the software?
0
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1answer
136 views

How to apply control points in LiDAR?

I am new to LiDAR point clouds and I have a big issue. I have LiDAR data for 30 km and I have 5 - 6 control points. My point cloud is inaccurate (have averagely 3-4 m error in xy and 50 m error on ...
0
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1answer
237 views

Locating outliers in LAS Dataset with ArcGIS?

According to the statistics and symbology of my LASD I have outliers. See below: How can I locate them in ArcGIS 10.x and do further analysis with them? I cannot query the dataset or select point? So ...
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0answers
183 views

Visualizing LiDAR data in a detailed footprint of rooftops with ArcGIS [closed]

For the last couple of weeks, I have been doing a research for making a detailed footprint with LiDAR data. The detailed footprint is needed for visualizing a 3D model. With a detailed footprint I ...
2
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1answer
41 views

How does MERIS collect vegetation height data?

In GlobCover 2005 and 2009 project, the sensor used for spectral data collection was MEdium Resolution Imaging Spectrometer (MERIS). It observes the Earth in 15 spectral bands in visible and near ...
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0answers
92 views

Rice Field Levee Contours - .2 foot interval needed - LiDAR data? [closed]

I am a rice farmer in Arkansas and would like to create levees along contour lines in a field at a .2 foot interval. How could I utilize LiDAR data to map 0.2 foot contour intervals across my area of ...
0
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1answer
342 views

Difference between files of extension .asc, .asc.aux.xml, .aux and .rrd?

I have received ASCII data from a client. These ASCII files have been created from LiDAR data. For each tile there are 4 different file types: Filename.asc Filename.asc.aux.xml Filename.aux ...
2
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1answer
103 views

How to incorporate stdmetrics in gridmetrics function?

I am attempting to feed the lidR gridmetrics function a list of metrics. I can generate the list of metrics within a function (following this example): myMetrics = function(z, i) { metrics = list( ...
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0answers
89 views

Completing Coordinate transformation?

I have two airborne lidar datasets and, for purposes of comparing change between the two, would like to standardize the vertical and horizontal coordinate information for each. The plan is to ...
9
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4answers
2k views

How to distinguish buildings from vegetation in LIDAR data?

In order to extract the vegetation mask in ecognition, with object base analysis, with creation of the rule sets, the buildings were also classified! Any idea how to extract building from vegetation? ...
3
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0answers
52 views

Checking and enforcing downstream Z constraint for synthetic streams?

Assume I've delineated planar (X, Y) stream breaklines to use them for enforcement of bare ground DEM derivation from high density lidar data. The stream features are in a Z and M enabled polyline ...
1
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2answers
1k views

PDAL: Couldn't create filter stage of type 'filters.voxelgrid'

I have the following PDAL pipeline: <?xml version="1.0" encoding="UTF-8" standalone="no"?> <Pipeline version="1.0"> <Writer type="writers.pgpointcloud"> <Option name="...
1
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1answer
124 views

PDAL: Argument references invalid/unused stage: 'filters.voxelgrid'

I am running into an error when running pdal translate on Mac OS High Sierra: PDAL: Argument references invalid/unused stage: 'filters.voxelgrid'. This is the command I am using based on a PDAL ...
1
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0answers
467 views

Generate Height map for unity-3D from Lidar point data [closed]

I have Downloaded a data set from udacity open source self driving car program from here. It is a ROS (Robotic operating system) BAG file more info.The BAG file contains data collected from Velodyne ...
2
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2answers
122 views

Finding pixels in DEM with 5% slope or less? [closed]

I am trying to determine if a given property may be amenable for a ground based commercial solar project. Among basic requirements there is flatness (5% slope or less), so I am trying to determine ...
1
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1answer
33 views

SPDLib spdinterp Error: Two file paths should have been specified (e.g., Input and Output)

I am using spdinterp from the SPDlib to produce a digital terrain model using the following command: spdinterp --dtm --topo -r 50 -c 50 --overlap 10 -i NATURAL_NEIGHBOR -f HFA -b 1 /Users/aaron/data/...
1
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1answer
910 views

LASTools' lasview gives no output in QGIS? [closed]

I've downloaded the latest LASTools into the current folder in QGIS and have tried running lasview on a few .las files I have on hand. As far as I can tell the files are georeferenced but I am not ...
3
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2answers
2k views

Canopy Height Model of LiDAR data in QGIS?

I have a DTM and DSM files. I want to develop a Canopy Height Model (CHM) in QGIS. Is it possible?
7
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3answers
3k views

LiDAR (.las) to bare-earth DEM: average points spacing and cell size?

I am using ArcGIS 10.1 to generate a DEM (bare earth) from LAS dataset. To accomplish this, I use Las Dataset to Raster tool as described in Esri website. I have read here and there in the web that ...
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0answers
74 views

Filtering LAS Dataset and using output for raster conversion? [duplicate]

I have problems with filtering LiDAR data within geoprocessing tools and python scripts. It simply doesn't work despite everyting looks correct. Filtering works only when I apply filter in properties ...
2
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1answer
1k views

Converting LiDAR .las to .xyz with LAStools outputs incorrect projected coordinates?

I have an application that can import terrain data in an XYZ text format where X = latitude, Y = longitude and Z = elevation. I am trying to convert a LiDAR .las file to this format using las2las. ...
2
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2answers
3k views

LAS dataset to raster with ground points only [duplicate]

I'm trying to make a raster from an LAS dataset. I want to only use points classified as ground, but I can't figure out how to do this. What I've tried is: Create LAS dataset from 2 .las files. ...
3
votes
1answer
740 views

Specifying LAS dataset filters in ArcGIS ModelBuilder?

I'm trying to create a tool in the ArcMap ModelBuilder to extract a canopy height raster from LiDAR data. I need to create rasters for ground elevation and first return. I've got my LAS dataset, and ...
0
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1answer
113 views

Batch ENVI IDL PointCloudFeatureExtraction results in unprocessed areas [closed]

I have an IDL-ENVI code to batch PointCloudFeatureExtraction for lidar tiles across a large area, however, when run, the output results in lower areas of each tile as "unprocessed". So my question is ...
5
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2answers
625 views

Cleaning LiDAR points that classification algorithm misses?

There are numerous methods for classifying ground and not-ground points from raw LAS point clouds. They all do a great job, depending on local circumstances, but inevitably even when algorithm and ...
3
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1answer
175 views

Where are Esri LasDatasetBuilder examples?

Does anyone know of any working examples leveraging the new ESRI ArcGIS 10.1 Lidar classes i.e LasDataSet or LasBuilder class? I've looked around on http://resources.arcgis.com/en/help/arcobjects-net/...
1
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1answer
137 views

Finding closest tree in LiDAR data with respect to electricity line? [closed]

I have a LiDAR point cloud. As you see I have one electricity line. I want to vectorise it and then I want to find the closest tree point to electricity line. How can I achieve? I am open to all ...
4
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2answers
12k views

Creating DEM from geoTIFF or asciiGRID LiDAR data?

For a home project I want to 3D print an area from a map. I have downloaded a geoTIFF file and an asciiGRID file from the Tasmanian governments spatial program "TheList". The two files are here: ....
1
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4answers
1k views

Exporting ground returns (.las) from classified point cloud?

I have lidar data that is classified as several categories (water, ground etc.). I need to open this lidar data in some software (it will be great if it would be a open source software) and delete a ...
4
votes
1answer
488 views

Extracting LiDAR metrics with TerraScan?

I want to extract from a las file statistics such as height percentiles (percentile 95, for example) among others. I can do it with Fusion (using Cloudmetrics and Gridmetrics tools), but I would like ...
6
votes
1answer
2k views

Breakline detection algorithms for LiDAR dataset?

I'm searching for algorithms or open source tools I could use to detect breaklines from a LiDAR dataset; more specifically, from the terrain points of the dataset. At the moment the only thing I've ...
3
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2answers
2k views

Converting from shapefile or raster formats to LAS? [closed]

I am looking for a solution to convert either from ESRI shapefile format to LAS or from a common raster format to LAS. I have access to following software: ArcGIS 10.2 for Desktop (arcinfo with ...
4
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2answers
974 views

Classifying raw LAS data as bare earth in ArcGIS for Desktop?

I have a raw LAS data that has only one return (no second/ third.. return) and not classified yet. The only information I have is intensity and elevation. Is there any way that I can classify bare ...
2
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2answers
349 views

LAStools menu seems to be incomplete in QGIS?

I am using QGIS 2.18.2 Las Palmas on a MacBook Pro running OSX 10.13.1 High Sierra. I followed Martin Isenburg's instructions how to install LAStools toolbox in QGIS and the LAStools menu is available ...
0
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1answer
345 views

Which type of point cloud is more accurate: from airborne LiDAR or aerial photos?

I have been offered two types of point cloud for my 3D Project. The data will be used by the environmental agency in various projects e.g. flood-risk analysis, dyke conservation, and nature ...
3
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2answers
499 views

Finding tree canopy width using PDAL?

I want to classify (and separate) houses from trees (high vegetation) in point cloud data using PDAL. I use height filter for this purpose. Our high Vegetation lies in the range between 5 and 10 ...
3
votes
1answer
106 views

Representing multiple polylines in unique vector layer?

I have imported a layer which contains a lot of lines. They overlap each other in a cross kind of pattern. When zoomed out it can look like this: When zooming in on one of the broader lines it looks ...
6
votes
2answers
6k views

Drawing irregularly shaped boundary polygon around set of LAS points using ArcMap?

I am working with a set of LAS data which is irregularly shaped, picture a starfish as the point coverage, surrounding the starfish may be water on one side, may be more land elsewhere but no points ...
1
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0answers
473 views

r.in.lidar Error: 'Raster map not found' in QGIS 2.18.14 GRASS [closed]

First of all I would like to say, that I have checked all the open threads (with almost the same title) about r.in.lidar errors and in general GRASS and it's "raster map not found" errors within QGIS ...
4
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1answer
386 views

Elevation maps from point clouds: TPS vs. other methods?

In the reply to another question, @thehealingprocess refers to "...a comparison of interpolation methods for interpolating elevation maps from LiDAR clouds, and in almost all scenarios thin plate ...
2
votes
1answer
729 views

Clipping LAS data with multiple shapefiles

I am looking for a method to clip with multiple shapefiles (139 shapefiles polygon) a lidar.las file. I'm using the software Fusion, as described in: How to clip LAS data using shapefile polygons ...
1
vote
1answer
175 views

Batch processing multiple files with MCC-LIDAR?

I want to classify ground points from multiple LiDAR tiles (.las files) using MCC-LIDAR software. I already made some research and I have found this sourceforge thread; however, it is not that clear (...
20
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9answers
16k views

Viewing LiDAR data from web browser?

I am looking to host lidar data on my own server and give clients the ability to view that data through a web browser as a 3D point cloud (file would be in .las format or equivalent), possibly with ...
2
votes
1answer
826 views

Problem importing LiDAR data in GRASS 7

I compiled GRASS 7 on Ubuntu 12.10, with liblas in order to run r.in.lidar and v.in.lidar. I now want to import .las data; the option in file -> import raster data -> LAS LIDAR points import is given ...