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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working with lidar points

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 ...
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95 views

Processing LAS dataset in QGIS 2.8.2

I need to extract DEM from LIDAR dataset in QGIS 2.8.2. I have installed LAS tools in QGIS. I cannot configure my LAStools because I do not get Processing-->Options and Configuration and instead I get ...
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54 views

LAS .PTC classes into ESRI LAS to Mulitpoint

We have some Lidar data that has been classified based on visable features (i.e. trees, streets, buildings, etc.) These LAS data are used inside inside Microstation w/ TerraScan connected to a PTC ...
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22 views

How to remove las2dem streaks from raster dem

I've created a series of DEM files using the las2dem tool from LAStools, however since I don't have a licensed version they have black streaks running across them. Does anyone know a good method for ...
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727 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 ...
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56 views

Import point cloud into PostgreSQL/ pdal pipeline fails

I have a point cloud dataset that I would like to upload to my postgres/postgis database. I followed this tutorial and I could install everything without problems (on ubuntu 14.04. On ubuntu 12.04 ...
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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, ...
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19 views

Deleting only specific LiDAR points in QTM with Mensuration tool

I'm using Quick Terrain Modeler (QTM) 64-bit v8.0.3.4 - I have a set of LiDAR data that has some points that I want to delete, but due to their location it is hard (if not impossible) to delete them ...
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66 views

Using GPS to field walk through a LiDAR scene

I am doing field surveying for archaeology using Lidar. If I attached a USB GPS to my laptop would it be possible to track where I am "in real time" on the Lidar as I am field walking? I'm wanting to ...
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1answer
74 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 ...
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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” ...
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101 views

Extracting wall information using LIDAR data?

I'm trying to extract wall using the LIDAR. I have tried Fusion, Whitebox, Lastools in Arcgis, Saga and Envi. Those are tools that I can use. The walls I am interested are mainly 1 meter high. Some of ...
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2answers
580 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.
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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 ...
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2answers
4k 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? ...
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2answers
93 views

LiDAR GUI tool for selecting and saving groups of points?

I'm working in a small group that is processing LiDAR data with some custom code. We need to see how well our stuff is working so we need samples of "truth" data that we can compare our output ...
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1answer
70 views

What is NIR LiDAR?

Can LiDAR sensors collect near-infrared (NIR) data at the same time or does there need to be a separate NIR camera that is combined with the LiDAR data after collection? Blue Marble makes reference ...
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1answer
39 views

Extracting desired LiDAR points with Quick Terrain Modeler

There may not be a 'better' or 'easier' way to do what I'm asking, but I figured I'd give it a shot and ask around. I'm using Quick Terrain Modeler v8.0.3.4 (x64) and have used the ZEB1 Handheld ...
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1answer
72 views

Why does my hillshade .ovr display in lower resolution in QGIS?

I have viewed a lidar terrain model hillshade .ovr file on QGIS and Arc and Arc has significantly higher resolution than QGIS. Any thoughts as to why this would happen and ways to enhance resolution ...
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2answers
38 views

Coordinate formatting for swath data - to polygon

I've got a CSV of Lidar coverage swaths in the below format. Each run or strip is tied together via run_id. I'm assuming L is for left, R is for right and M is for middle. EDIT: These are coordinates ...
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248 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 ...
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How to increase FUSION-LTK lidar processing productivity?

I am processing Lidar data with FUSION-LTK. My study area contains 5 blocks of 1000 las tiles per block. Each block is broken into approximately 4 subblocks of 250 las tiles. I am calculating grid ...
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294 views

Extract road defects from terrestrial LiDAR, in Erdas 2012 or ArcGIS10.1

I'd like to extract road defects from a lidar point cloud. So, wherever a road surface drops or raises by a few mm relative to 100 cm around it. I know it's possible but I just can't find or figure ...
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70 views

CPUs to process lidar data using ArcGIS for Desktop?

I am looking to build a computer to process data in ArcGIS 10.2.2. The main use will be to rasterize 10-100's GBs of lidar data. However, I am unclear as to the capabilities of ArcGIS 10.2.2 to ...
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55 views

LiDAR data download, merge and mosaic (Minnesota state)

I have been using the toolbox found here to download LiDAR data for MN (Minnesota-US). The tool is very convenient for downloading multiple tiles but the merge/mosaic function of the tool is ...
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253 views

Failing to merge rasters in QGIS

I am new to QGIS but have some familiarity with other GIS software (namely ArcGIS). I want to merge a number of LiDAR digital elevation model (DEM) tiles (specifically, 30 individual tiles) to ...
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2answers
683 views

Installing LASTools to QGIS on a Mac (or other LAS processing plugins)

I recently saw this link how to install LAStools toolbox to QGIS. The problem is that the instructions are only for Windows users. Now I wonder if it's possible to install LAStools on a Mac with QGIS ...
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80 views

Filtering noise out from bare-earth DEM with terrace fields?

I have a 1m bare-earth DEM, derived from LiDAR data, representing a terraced landscape. For the sake of any subsequent use of the DEM (e.g., least-cost path, cost surface analysis, and the like) I am ...
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2answers
102 views

QGIS error when importing .asc LIDAR data

First let me say that I am novice in GIS department. As archaeologist I had only some courses 8 years back when i was still studying. Now, the problem: When I try to import .asc as raster layer I ...
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129 views

LiDAR dataset displaying 500 meters to the east of correct position

Why does my LIDAR dataset show up ~500 meters to the east of the correct position even though a spatial reference/coordinate system is provided? Some background: The LIDAR data were downloaded from ...
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1answer
127 views

Making a 3D map with shapefiles, lidar and aerial image data

I want to try to make a simple 3D map for a small area (10 square miles) with some housing, some roads and some vegetation on it. My geodata is as follows: shapes with houses/roads/vegetation. ...
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562 views

What are LiDAR returns?

Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system.
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42 views

Looping for importing and interpolating a lot of LIDAR files?

I'm quite new to Grass Gis and I'm trying to make DEM (digital elevation model) for modelling flooding. I have 170 *.xyz files, which need to be scanned for extents (r.in.xyz -s input=...\filename.xyz ...
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346 views

QGIS 2.8 problem accessing GRASS commands

QGIS 2.8.1 Win7 64 bit installed with osgeo4w-setup. I’m trying to run GRASS commands on a LIDAR raster layer but I get the following message: Missing dependency.... GRASS not installed in your ...
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2answers
295 views

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

I am 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 is only ...
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1answer
67 views

Calculate change in canopy height over 10 years?

I want to know how many "tall" trees (greater than 30 m) fell down between 2005 and 2015. I have LIDAR imagery from 2005 and 2015 from an area where many tall trees are known to have fallen due to ...
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3answers
269 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 ...
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1answer
371 views

wine + LAStools in QGIS 2.8.1, Ubuntu 14.04

I can't get wine + LAStools to work in QGIS 2.8.1 (ubuntu 14.04). I only get the 22 open source functions that comes with QGIS. Outside qgis wine + LAStools works fine. My guess is that I am not ...
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3answers
156 views

What can I do with lidar returns of 6 or greater in LAS 1.2 specification?

I have lidar LAS data that contains a number of points that represent returns 6 or 7. The data is supposed to be in ASPRS LAS 1.2 specification, which does not allow return numbers (echos) greater ...
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84 views

LAG LiDAR Analysis GUI installation guide

Does anyone know how do I install LAG lidar Analysis Gui? LAG by arsf This is my situation: I'm using debian 8 test. I installed this library: boost (yes) * GTKmm (yes) * GTKGLextmm (yes) * GThread ...
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71 views

How to delete duplicate LiDAR points?

How can I delete duplicate lidar points. I incorrectly read the same las twice and saved as a one file resulting in duplicate XY points. How should I delete these duplicate points?
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38 views

How to merge grd files programmatically, ideally in Python?

We currently get LIDAR data from the field in grd format. Sometimes this data is overlapping. This data gets fed into a python program that does some analysis. What I'm after is some way of ...
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37 views

Oriented stereopair in ERDAS

I am trying to orient a set of intensity LiDAR images in ERDAS Stereoanalyst for stereo digitizing. The set is consisted of an intensity image and its stereomate. Stereoanalyst is configured for ...
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1answer
117 views

Correcting class codes of LiDAR files in ArcGIS

Is there any procedure to automatically correct lidar classification? My LAS Dataset has water listed as ground and buildings listed as vegetation. Just wondering if there is any option to fix this. ...
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1answer
74 views

Make a ground mask raster with the Greater Than tool

I'm trying to see if I can replicate the Esri solar suitability site example from this article. I fail on the creation of the binary ground raster. I have made a Bare Earth raster from LiDAR ground ...
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84 views

Format of raw LiDAR data (ToF data)

I am doing a project where I need to simulate LIDAR data, and I am looking for specifications on how raw LIDAR data looks. I want the format of the data before it is translated to x,y,z coordinates ...
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407 views

Looking for free / open source Lidar web viewer?

I have lidar data which I want deploy my users using web viewer. I will probably hold the data in PostGIS (not sure yet). Is there good open source/free lidar viewer that I can integrate with ...
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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 ...
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137 views

LiDAR/Geo-TIFF Tree Crown Segmentation

I am looking for any source code that does tree crown segmentation/delaunitaitoun with LiDAR point clouds or their respective greo-TIFFs. So far I can load and view both LiDAR file and its TIFF in ...
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1answer
135 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, ...