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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how to install and use lastools then create contour map with .lasd file [on hold]

Firstly, consider me an amateur by every sense of the word. I have QGIS 2.4 Chugiak for windows. I have an .lasd file with quad data that I want to create contours with. I have tried following ...
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37 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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25 views

LiDAR data for Palawan (Philippines)

Is there any public or private sources of LIDAR data for San Paul river in Palawan (Philippines)? Searching online has not lead me to any sources, and I am unsure how the commercial world of LIDAR ...
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2answers
46 views

r.in.xyz doesn't work in GRASS

I have these LIDAR data *.xyz files (1st col x, 2nd col y, 3rd col z) 485000.16 6508997.48 1.84 485001.27 6508998.92 1.86 485001.02 6508996.68 1.85 485000.77 6508994.45 1.79 485000.52 6508992.19 1.79 ...
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41 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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1answer
67 views

DEM creation with C++ application

I am implementing a C++ application that must produce DEMs from LIDAR data. I am following the next workflow: Write .las files from lidar data. Use PCL algorithms to transform/filter the point ...
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26 views

Contour Creation for Export to CAD including z values using QGIS

I have LiDAR tiles for my appropriate areas where I need to extract the contour and relevant height information for use in flood studies. I am able to draw out the contours from the data, however ...
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5answers
49 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
31 views

From LiDAR .txt to QGIS map

I have Lidar data in .txt files (1000 to 26000 KB), where 2nd column marks x-coordinates, 3rd col y and 4th col z. 8 485000.16 6508997.48 1.84 66 Last 2 485001.27 6508998.92 1.86 82 Last 2 485001.02 ...
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1answer
66 views

Reprojection error

I have a lidar file (file.las) with the following spatial reference: Spatial Reference: PROJCS["NAD83 / UTM zone 11N", GEOGCS["NAD83", DATUM["North_American_Datum_1983", ...
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12 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?
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36 views

Classification of above ground LiDAR points in ArcMap

I recently used the LAS Dataset toolbar to classify a .lasd file. The process classified the majority of points as unassigned with the rest being ground points. The study area has many tall buildings ...
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1answer
102 views

How to georeference LAS files?

First of all, I am a newbie in GIS. I have a lidar point cloud with GPS and telemetry data associated. Then, I transform coordinates of every point to an ECEF coordinate system and finally I ...
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78 views

Extract DEM and DTM information from LIDAR image using E-Cognition

I´m trying to extract DEM and DTM from a LIDAR file. I just rasterize the image but then I don´t know which algorithm I need to apply to obtain the DEM and DTM information in different models to be ...
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3answers
569 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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4answers
230 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 ...
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130 views

LiDAR point cloud to 3D model of street

I am looking for a way to convert point cloud collected through a Riegl LiDAR scanner to a perfect 3D model of a town. The sample data is from vehicle mounted scanner, but final data is going to be ...
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1answer
233 views

How to create NDVI map From LiDAR intensity and RGB image

I am new with GIS and I've been looking for ways on how I could create a NDVI map from LiDAR intensity and RGB image. Is there any way I could do this? I have read that you could create an intensity ...
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1answer
75 views

Correct georeferenced LiDAR data

Often I obtain LIDAR data for concept studies and conventional survey (in dxf format) over a small portion of this. The LIDAR typically covers the broader area and is used for broader studies, ...
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2answers
51 views

Selecting percentage of points from multipoint layer (ArcGis)

I am currently working with las dataset of small area, and I want to run some quick analysis on this area. Since my PC is not the best, I am looking for tool like "extract 50% of multipoints to new ...
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75 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 ...
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3answers
103 views

Which raster resolution (DEM) can I get out of lidar data with variable grid width?

I have ASCII files in *.xyz format and want to generate a DEM out of it. According to the information about the data the *.xyz files are containing variable grid widths - from 1 meter to 4 meter. ...
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2answers
74 views

LIDAR online training

Beside ESRI's LIDAR online training, I'd like to work on some hands-on training that I can learn about LIDAR. Are there any good LIDAR out there that I can get some training with the datasets ? ...
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1answer
60 views

Landform design/3D in ArcMap 10.2

Im a self taught ArcMap user working in a small business, so no one to bounce problems off. My aim is this: I would like to be overlay different surfaces, manipulate them, and display them. The ...
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2answers
179 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: ...
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1answer
139 views

Convert downloaded LiDAR info to DEM in GRASS

I have downloaded LiDAR information as a .asc file and a .tif file, and even though I have tried multiple methods to convert them to a dem I am having no luck. Grass GIS says there is an invalid ...
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2answers
135 views

Cleaning blocks pattern from urban LIDAR (blocks uplifted from streets)

We have a 1-meter LIDAR DEM from a city. A small subset can be downloaded from this link: This screenshot shows raw DEM with gray palette (darker belts are streets, and greyish and whitish ...
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83 views

How complete are the Fusion tools in QGIS?

How complete are the Fusion tools in QGIS? I have them installed and (vaguely) working, but there are only about ten of them. Is the idea of having just a few tools available, that one can use ...
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2answers
148 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 ...
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1answer
97 views

How to convert different lidar data formats to raster DTM and measure its geographic position accuracy?

I'm trying to generate a DTM from lidar data and I'm new in the this field. I have different kind of files which describe the same area (different versions): *.dtm *.xyz *.xyz with variable grid ...
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53 views

Mine Grid to UTM

I have been given spatial data (lidar) that was collected in mine grid feet in ASCII format. I am using arc to process but need to define a projection does anyone know how to do this or any other ...
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2answers
54 views

Using ASCII LiDAR data tiles which are centimeter rounded (n Z) in ArcGIS Desktop seems to round them to meters?

I try to use four LIDAR tiles in .asc with arcgis9.3. All of this tiles are centimeter round (in z) but one of them seems to be round to meter (see tile on the left up corner on the image below), ...
3
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1answer
64 views

What's the deal with “degradation” and lastools?

I've read a few cautions online and heard a few from colleagues. If you don't purchase a license for lastools, the non-open-source functions will somehow degrade your data or results? Is this true? ...
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57 views

laspy reading las file

New to laspy and encountering an error. The first code block describes the file header, the second (In[24]) fails to open the file with laspy: In [21]: import numpy import laspy from laspy.file ...
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142 views

Is cost of new LiDAR data reasonable for deliverables provided (in Canada)?

My organization is considering hiring a company to capture new LiDAR data to help with current storm water issues that we are currently experiencing. I am a GIS analyst that has been assigned with ...
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2answers
156 views

Removing incorrect (non-ground) points from LiDAR data? [duplicate]

I have ground lidar points, nonground lidar points and tree lidar points. The problem is some of the ground lidar points are incorrect. For example, the highest elevation values of tree and building ...
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2answers
116 views

How to filter LiDAR data by scan angle?

I am looking to filter LiDAR data (.las format) by scan angle specifications (e.g. keep all points < 15). From a basic Google search, it appears that the LibLAS library has the ability to filter by ...
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2answers
126 views

Problem with Y offset shift of LAS file (las2las)

I'm trying to set the origin of a georeferenced .las point cloud to be coordinates 0,0,0, essentially stripping the georeferencing. The only way I could think to do this was subtract the minimum X, Y ...
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182 views

Open-source reader of Leica C10 terrestrial LiDAR proprietary file format

I have a Leica C10 terrestrial LiDAR (laser scanner) system. The system creates and stores point cloud data in a proprietary .bin file. Currently I have to use Leica's proprietary LiDAR software, ...
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123 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 ...
3
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1answer
110 views

What is the status of any ongoing efforts that will allow QGIS to display .las files directly in the main 2D window?

After some research on QGIS's ability to display .las files, I came to the conclusion that it is not possible: currently any attempt at this requires converting .las to .shp as described here and ...
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1answer
268 views

River boundary (bank) extraction from LiDAR

Is there any way to extract a river boundary (bank) from LiDAR data and its products (DEM, intensity image and slope) automatically? Digitizing is very time consuming.
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3answers
264 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 ...
4
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1answer
94 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. ...
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2answers
59 views

Rename las files with Python [closed]

I have a bunch of LAS files that have been delivered with different naming conventions. I want to rename the files to all have the same uniform naming - based on the easting and northing coordinates ...
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82 views

Volume calculation analysis with Quick Terrain Modeler 8.0.2. (QTM)

I have been unsuccessful in finding a tutorial, guide or example of the 'Volume Calculation' analysis tool in Quick Terrain Modeler. http://appliedimagery.com/ I was wondering if anyone else has any ...
3
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1answer
39 views

Algorithm behind custom tool of ArcGIS for Desktop called xyz2grid21?

I am a researcher from Romania and I have used xyz2grid21 ArcGIS tool (by Min-Lang Huang) in order to convert xyz files (LIDAR data) to ASCII and ESRI grid in order to obtain a DTM. I need to know ...
3
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2answers
106 views

How to manipulate lidar map using sun azimuth

Hi I am VERY new to QGIS and am struggling. I have a Lidar map and want to change the view so that the ground shadow is manipulated (looking for archaeological anomalies). I think it is the sun angle ...
3
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1answer
80 views

Convert coordinate system of Lidar or TIN?

I have Lidar data and I want to create a TIN from it, and then run the TIN Triangle tool to create a polygon shapefile of the triangles. The only thing is that the Lidar data is in a UTM CS with ...
3
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3answers
199 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 ...