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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2answers
155 views

Creating planes, eg roof surfaces, from LiDAR/DSM data

Bit stuck here, Im capturing the area of roof tops of buildings from a DSM (derived from LiDAR data) which has not been much of a problem. I can then also derive angle, hillshade and aspect but it ...
1
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2answers
178 views

How do you convert a .lasd (Lidar) coordinate system?

How do you change a coordinate system for a .lasd (Lidar) dataset? The file is currently in UTM_Zone _15N and I am trying to convert it to IL_East.
7
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2answers
256 views

Practical Building Extraction Algorithm Implementation

I've been reading many papers over 3D building extraction using LiDAR data and Aerial images. I see that there are many different algorithms for doing such things, such as this and this. Those ...
3
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1answer
205 views

Lidar data in ArcGIS 10.1

Problem: I have a set of LAS files that doesn't display in Arcmap. Details: I try to use LAS to tin in Arcmap to convert my LAS points to a TIN. However, when browsing to the folder with the files, ...
12
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4answers
1k views

comparing two DEMs

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 wanted to compare how the Digital ...
6
votes
1answer
173 views

Problem reprojecting LIDAR data with Liblas

I am currently trying to reproject a LIDAR file (.las) using the Open-Source LibLAS, compiled on a Scientific Linux server. The Original data is in Oregon Lambert, NAD83 (EPSG:2992), and I am trying ...
2
votes
1answer
96 views

LAS sample file for electric utility poles

Does anybody know a souce where I can find a sample LAS file that has electric utility poles? Like seen here - http://resources.arcgis.com/en/help/main/10.1/index.html#//015w00000040000000
3
votes
1answer
85 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 ...
1
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2answers
262 views

Tool for exporting las data

Is there any tool available for extracting the X, Y and Z channels from a .las file and exporting them to a .csv or similar file?
2
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2answers
347 views

How do I import UK Environment Agency Lidar data (.asc) into Quantum GIS

I have downloaded Lidar data from the UK Environment Agency as ESRI ASCII files but being a complete novice as far as GIS is concerned I do not know how to view them. Quantum GIS was recommended to me ...
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2answers
267 views

How to develop a Canopy Height Model of LIDAR data in QGIS?

I am having a DTM and DSM files .I want to develope a Canopy Height Model in Qgis is it possible?
1
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1answer
59 views

rooftop modeling

I´m trying to model building rooftops based on a LiDAR dataset. I've already interpolated using Delaunay's triangulation a DEM with 1m resolution. Due to LiDAR data is not accurate in building edges, ...
1
vote
1answer
130 views

How do I install the las2ogr tool from liblas in Windows using the osgeo4w installer?

I was wondering if anyone has used the LAS2OGR tool? I heard about this from a previous post. The webpage gives the usage: http://www.liblas.org/utilities/las2ogr.html las2ogr -i mydata.las -o ...
6
votes
3answers
819 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 ...
1
vote
1answer
134 views

Grass 7 .las data import problem

I compiled Grass7 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 ...
2
votes
2answers
4k 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 ...
7
votes
2answers
965 views

Huge point cloud laser data in PostGIS - Storing and Processing it

I wonder, how it's possible to store huge sets of laser scanned point cloud data in PostGIS, with the time-aspect for processing it in mind. I know, there exists a geometry-object Point in PostGIS. ...
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0answers
163 views

Feature Extraction from LiDAR in Erdas 2012 or ArcGIS10.1

I know it's possible but I just can't find or figure out a workflow for it. Erdas Webinars has the workflow for ver 2011 but this is very different in 2013 as it uses a raster img file instead. I ...
4
votes
1answer
330 views

arcpy “The table name is invalid”

I wrote a script that, ideally, loads raw .las (LiDAR data) files into a geodatabase, then creates a terrain from the multipoint files that are created. When I run the script though I get: ...
2
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0answers
699 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 ...
4
votes
1answer
468 views

Linux alternatives to visualize and analyze LiDAR datasets

For a long time I have been using softwares based in Windows to visualize and analyze LiDAR data sets for forest application. Recently I have started to move all my work to Ubuntu platform, but I'm ...
12
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7answers
742 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 ...
6
votes
1answer
464 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 ...
5
votes
1answer
355 views

Floor height creation from Aerial Lidar/Imagery only

I was wondering if it is possible to generate the floor heights of buildings from aerial lidar? We don't have terrestrial lidar or stereo imagery. I don't need the ground DEM level or the roof (DSM) ...
4
votes
1answer
355 views

How to repair and clean contours from high data resolution (lidar)?

I'm unsuccessfully trying to make a bathymetric map with contours extracted from Lidar data at 1 m resolution. The extracted contours have a lot of artifacts like dangles and islands. First I used ...
7
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1answer
164 views

How to decide possible areas for water retention using lidar

I have lidar imagery for a watershed and am trying to process it so that a landowner know if they can hold water on their property or where they can hole the water (this is the more important part). ...
3
votes
1answer
126 views

Problem with mcc-lidar

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: insuficient memory; ...
4
votes
3answers
380 views

Finding outliers with wrong Z values in LIDAR data

I have more than 2000 XYZ .txt files and I have to do QC: let's say I have file, which I converted to multipoint (or even singlepart feature). I have mean Z value for a file, but ... if most of the ...
2
votes
1answer
162 views

Help with Parameters for MCC-LiDAR

I am attempting to use MCC-LiDAR to reclassify points (.las) originally classified using TIFFS. However, I seem to either be misunderstanding what the parameters really mean or where to get the ...
7
votes
5answers
496 views

Processing Full-waveform Lidar?

Does anyone know of a good software package for processing full-waveform lidar? Also, does anyone know of a good tutorial on processing full-waveform lidar?
6
votes
3answers
621 views

Can I use LASTools to classify point data?

I am presently using LAStools to analyse LiDAR data. Can LAStools classify the points into various features such as vegetation, roads, buildings etc? If so, how is it done?
11
votes
4answers
512 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 ...
7
votes
2answers
207 views

Aerial LiDAR: What is an acceptable resolution?

I am in the process of initiating a project involving laser scanning. The area to be scanned i s approximately 5000 km². We are initially going to use the data to create a solar potential application, ...
3
votes
2answers
234 views

How to clip from a point layer using postgis?

I've loaded a LIDAR xyz file into a PostGIS2.0 database and created a 3D point geometry column ("tblCLOUD") from the data. I've also loaded into the database a shapefile that contains six ...
8
votes
2answers
1k views

How do I combine high resolution and generalized hillshade rasters to produce enhanced shaded relief?

I often add LiDAR data to a map along with a shaded relief. Most of the time i have to generalize the LiDAR dem depending on the scale of the map. Still, there is often too much detail and mountain ...
12
votes
2answers
428 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 ...
7
votes
8answers
3k views

Where can I get pointcloud data?

Is there any freely available pointcloud data? I'm especially interested in dense clouds of small areas(5m to 100m radius) but anything else would be fine too.
3
votes
4answers
1k views

What are Limits on ArcScene and LiDAR?

I am trying to load anywhere from 5 to 10 LIDAR TINS into ArcScene. I am using ArcGIS Desktop Evaluation (student) 9.3.1. I just built a new computer with a AMD Phenom II X6 1090T six core processor, ...
4
votes
2answers
369 views

how to retrieve average building height in urban areas?

I am looking for a way to collect data on the height profile of some cities over time. I don't need to produce a detailed 3D reconstruction of cities, nor do I need to detect and measure individual ...
1
vote
0answers
176 views

QGIS 1.7.4 crashes when using interpolation tool

I am currently using QGIS with Lidar data to produce hillshade images. I have split the lidar data in 20 files (31kb). Some of the files are working some are not. I have checked the files xyz are ...
14
votes
13answers
21k 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 ...
13
votes
6answers
5k 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 ...
1
vote
2answers
281 views

SAGA-GIS Produces different results in command line than GUI

I have been working on a lidar processing workflow using SAGA-GIS. I determined my workflow on a single tile in the SAGA GUI and now I need to batch the operations on 100 more tiles. I wrote a batch ...
1
vote
1answer
64 views

LASToMultiPoint_3d

Trying to use the arcgis python command LAStoMultipoint_3d as seen here. I'm running the code snippet against one of my LAS files. It creates a .shp, sbx, shp.xml, shx and dbf file. However, the ...
9
votes
3answers
2k views

Best method to aggregate 1m DEM mosaic to 10m DEM

I have a mosaic of a 1m LiDar derived DEM. I need to output a subset of the data as a 10m DEM. I am currently using the aggregate tool in ARCGIS 10 to produce a mean value for each new 10m pixel. ...
2
votes
1answer
141 views

Lidar Elevations Data

I am trying to acquire a method of detecting sub cm elevation without manually measuring from the field. Can LIDAR data produce this for me? Example: A 1500 foot long pipe conveying water from one ...
1
vote
3answers
369 views

How to create a generalized polygon layer from a raster?

I have a tiff file where I have extracted vegetation in a height interval from LIDAR. At the moment the picture is kind of blurry with no data cells between vegetated cells. I would like to create a ...
5
votes
1answer
2k views

Lidar - Automated building extraction (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? ...
1
vote
1answer
513 views

Aligning coordinate systems: gpx, LiDAR, shapefile

I am working on a project based on a lidar data set (for use in LidarViewer in Linux, a basic x,y,z viewer) that was downloaded from #1 below at Opentopo.org and looking to add onto this data set with ...
10
votes
3answers
1k views

optimize nearest neighbor query on 70 million extremely high density spatial point cloud on SQL Server 2008

I have about 75 million records in a SQL Server 2008 R2 Express database. Each is a lat long corresponding to some value. The table has geography column. I am trying to find one nearest neighbor for a ...