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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3answers
760 views

How to determine bare earth from unclassified LAS file

I have data in LAS format with RGB values created from Aerial photogrammetry using a UAV. I am trying to find a solution to extract the bare earth to create my DTM from the DSM. I have tried SAGA, ...
4
votes
2answers
8k views

Viewing .las format LIDAR data in QGIS?

Is there an easy path to visualizing this LIDAR data? I have QGIS, and some USGS LIDAR data in (.las) format downloaded from http://lidar.cr.usgs.gov/ . This means I have both the (.las) and ...
8
votes
2answers
2k views

Workflow for determining stream gradient?

As far as data goes, I'm working with NHD .shp files, 10m DEMs, and some LIDAR data. My goal is to determine gradient for 100m segments of a network of streams. I'm already able to do this, but I ...
12
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4answers
2k views

Comparing two Digital Elevation Models (DEMs) from LAS files?

I have two Lidar las files, one is original let's say with X points. And the other is copy of the first las file but with Y points, where Y is less than X. Now, I want to compare how the Digital ...
7
votes
3answers
2k views

How to clip LAS data using shapefile polygons and open source software?

I am trying to clip or filter lidar files (las, xyz) using a shapefile that contains multiple polygons. Is there open source software that can do this spatial operation? My las files are enormous, ...
3
votes
5answers
5k views

How to convert LAS to GRID/Raster for ArcGIS input?

I was wondering if there is an option to convert LAS (LIDAR data) to raster or GRID format that ArcGIS could read it.
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6answers
9k views

Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?

This is not the first time I've stumbled over this issue; it seems that I am unable to generate a correct drainage network model and the resulting catchments from full resolution (1m cells) LiDAR ...
3
votes
3answers
377 views

Assigning RGB values from Geotiff image to LiDAR data, using R

I have given a Geotiff image and its corresponding Lidar data (x,y,z) in UTM coordinates. I need to merge the Lidar data with the RGB values from the image. That means, at the end, I need to plot ...
6
votes
2answers
488 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 ...
22
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10answers
13k views

Working with LiDAR data using other than Esri software?

I will be working with LiDAR data soon and I am wondering what the alternatives to using Esri software to do this are, including open source solutions?
7
votes
1answer
4k views

Building extraction with LiDAR data (Improve Process)

I have the following process for automatically creating building outlines/footprints from Las files and was wondering if anyone can help improve it or has suggestions for other processes to use? ...
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11answers
28k views

How to a convert LiDAR XYZ files to DEM / DSM?

Normally consultants (LiDAR survey) provide me with data to my specifications; already in ESRI GRID or ASCII GRID format. This way LiDAR data can be easily used with ArcGIS. This time I only have xyz ...
6
votes
3answers
348 views

Filtering out canopies and buildings from DEM to have a bare earth elevation

Can anyone suggest methods in filtering out trees and buildings from a DEM so as to come up with a reliable DTM? What I have is a grid from a LIDAR data. I was going to clean out the unnecessary ...
4
votes
2answers
795 views

Comparing two TINs created using ArcGIS for Desktop?

I have the following two files: LiDAR las file1 Let's give it a name LiDAR las file2, contains the same file1 data, where number of points randomly removed. So if file1 contains X number of ...
8
votes
3answers
2k views

Do any open-source .Net libraries (commercially usable) exist for reading/writing LiDAR data?

I have a few LiDAR point data (.las files) with me. I would like to read the X,Y and Z from it using .Net. I found liblas, which is in C++ and I am not sure if it can be used commercially after ...
5
votes
3answers
1k views

How to make 3D building models from lidar data?

I have Lidar data, ground points and first returns. I have processed it and have ready tiles from which I am trying to build 3D building models. So far I was able to just extrude the buildings in ...
13
votes
5answers
752 views

Dikes extraction from DEM

I do have DEM of 1x1 meter and original LiDAR point cloud in .las, that DEM is made of. I need to extract river dikes (highest points of the dikes) to vector feature (point, polyline). Any idea for ...
5
votes
3answers
926 views

Finding outliers with wrong Z values in LIDAR data

I have more than 2000 XYZ (only ground points) .txt files and I have to do Quality Control (QC). Let's say I have file, which I converted to multipoint (or even singlepart feature). I have mean Z ...
3
votes
1answer
42 views

Clip multiple .las files data to polygon shapefile using FUSION

I followed this thread in order to clip .las data based off of a polygon shapefile. However I have over 100 .las files I need to clip based off of this polygon and merged into a single .lasd file and ...
3
votes
2answers
190 views

Clipping from a tiled LAS dataset with LASTools (for ArcGIS)

I have huge amounts of lidar data stored as tiled datasets per project. The "tiles" are separate LAS files based on our national map sheet setup (800 by 600 meter). To keep an overview of the data I ...
2
votes
1answer
58 views

Working with lidar points (LAS To Multipoint) in ArcGIS for Desktop?

Currently I'm working with the LAS format and want to transform from WGS84 to RSO Kertau Malaysia. I'm using ArcGIS-Las to Multipoint and Data Management Tool-Project and succeeded in the ...
1
vote
1answer
104 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 ...
0
votes
1answer
427 views

How do I read SBET file in python?

I have an SBET (Smoothed Best Estimate of Trajectory) file that I would like to read in python. I found these links that discuss options for reading/writing SBET files, but I was wondering if our ...
23
votes
2answers
4k views

Proper workflow for LAS to DEM conversion

I regularly come across LiDAR (.LAS) files with elevation data. When I do, I always struggle to find a way of converting them to a DEM for hydrological analysis. I have developed several workflows, ...
9
votes
5answers
3k 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 ...
12
votes
2answers
690 views

PostGIS interpolation / triangulation options

I'm looking for an open source workflow to automate DEM construction. We have a series of sites that fall within a LIDAR dataset. We want to create site specific DEM's for each site, and we're ...
9
votes
4answers
1k 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? ...
4
votes
4answers
720 views

Extracting tree crown areas from remote sensing data (visual images and LiDAR)

I am looking for a method to process a remote sensing image and extract the crown areas of the individual trees from the image. I have both visual wavelength areal imagery, and lidar data from the ...
13
votes
6answers
1k views

What is the best way to visualize multiple large LIDAR tiles?

I want to load approximately 10 large LIDAR tiles for analysis. I have tried using ArcScene but it appears there is a limit on how much data ArcScene can handle at one time. Each tile is 65-90MB in ...
5
votes
1answer
2k views

What is the procedure to load LAS files in QGIS 2.0.1?

What is the present procedure to load LAS files in QGIS 2.0.1? After some searching I found a paper outlining the procedure; however, it was for 1.8.something, and related posts here are all rather ...
3
votes
1answer
1k views

How to install LAS tools in Processing for QGIS 2.4?

Does anyone know were the processing menu moved in QGIS 2.4? Specifically I am trying to install the Lastools box for QGIS following these instructions. ...
3
votes
3answers
268 views

Removing duplicates from large LAS files

Are there any publicly and free (not necessarily open-source) applications that can remove duplicate points from LiDAR clouds? I would like something on the lines of lasduplicate -unique_xyz, which ...
2
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0answers
2k views

Simulate flood to assess Asset inundation footprints

I am trying to evaluate a number of flood gauges to assess at what levels of river height different flood risks would need to be issued. The gauges are currently set to warn of flood a couple of ...
6
votes
2answers
542 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 ...
3
votes
3answers
1k views

Problem operating LAStools in QGIS 2.6.1

I have a problem with LAStools in QGIS 2.6.1. I have never used QGIS to process LiDAR data before. I downloaded LAStools yesterday from the rapidlasso GmbH website. I unzipped the “lastools.zip” ...
3
votes
1answer
230 views

Problem with MCC-LiDAR (insufficient memory)

I am running mcc-lidar on a win7 64bits with 16gb of ram. Nevertheless when I try to process a las file with 1, 800 000 points using -s 0.5 and -t 0.3 the program tells me: Error: insufficient ...
5
votes
1answer
203 views

LiDAR Feature extraction specifications/standards

I have vector data representing forests/trees/buildings that have been automatically extracted from LiDAR data. I am looking for specification/guidance for LiDAR derived products, or any standard for ...
4
votes
1answer
163 views

What are definitions of watershed segmentation, local maxima, variable window search, regarding LiDAR for vegetation?

I am not familiar about Lidar. I want to measure trees height and number of trees. I guess, watershed = to locate the trees, local maxima = to measure trees height. I used these methods in SAGA GIS. ...
4
votes
3answers
431 views

LiDAR data density, returns per square meter

How can I compute a raster showing the number of return points per square meter using SAGA GIS or other open source software? My goal is to obtain a mask which would show me the places (cells) ...
4
votes
0answers
191 views

Has anyone used ArcGIS for 'automatically' detecting lineaments from a high-resolution (1m) DEM?

I have a set of DEM's produced from LIDAR data. I am wondering if anyone is familiar with or knew of any published research papers which looked at (semi-)automatically detecting lineaments /or ...
4
votes
3answers
796 views

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 ...
2
votes
1answer
148 views

Laz LiDAR files display extremely long thin line of points

I am having difficulty properly visualizing aerial LIDAR data from the csc.noaa.gov source. Taking any of the .laz files, the point cloud displays as an extremely long thin line of points. Zoomed in, ...
1
vote
2answers
389 views

How to create DEM from Lidar point cloud data?

I'm using ArcMap and I want to create DEM(s) over an area to have different outputs depending on which settings/filters I put in. I have access to laser point cloud data as my input files. I've worked ...
0
votes
0answers
16 views

Viewing, classifying, and processing LAS data using free open source software? [duplicate]

Is there a pipeline for viewing, classifying, and processing LAS data using free open source software?
0
votes
1answer
714 views

Is it possible to load an .las file directly into QGIS? [duplicate]

Is it possible to load an .las file directly into QGIS? I would like to be able to load LiDAR data and to be able to do analysis based various feature attributes; e.g., elevation, classifications, ...