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.

learn more… | top users | synonyms

4
votes
1answer
60 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 ...
3
votes
1answer
45 views

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

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 ...
4
votes
2answers
63 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 ...
4
votes
2answers
80 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 ...
8
votes
2answers
1k 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. ...
5
votes
3answers
149 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
votes
3answers
165 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) ...
13
votes
3answers
213 views

Account for bridge overpasses in a ground DEM to allow for water flow under the overpass

I have a bare earth DEM made from lidar data (A). It works well and has passed all accuracy tests. It is used in storm surge models. The problem we are having is on underpasses. I need to allow water ...
3
votes
1answer
86 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 ...
1
vote
1answer
123 views

What is the definition of pt_spacing on Point File Information tool?

I can't find any definition for the outputs of Point File Information tool (3D analyst), specifically the pt_spacing field. Is this the average distance between points, or the average number of ...
2
votes
3answers
142 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
635 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 ...
1
vote
0answers
45 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, ...
3
votes
1answer
161 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 ...
2
votes
1answer
197 views

Load LAS files in MapInfo

Is it possible to open LAS files within MapInfo? If so, how is accomplished in MapInfo 10.0?
1
vote
0answers
50 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 ...
20
votes
9answers
8k views

What are best alternatives to Esri software for LIDAR data?

I will be working with LIDAR data soon and am wondering what are the best alternatives to Esri software in your opinion? Which are generally considered to be the tops and flops of the LIDAR Sofware ...
8
votes
1answer
153 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.
2
votes
3answers
166 views

Merging multiple rasters with SAME spatial extent

So I began with lidar elevation data 1m resolution, and I performed a terrain analysis to extract specific ranges of elevation from the raster (1st picture is 0-1m elevation, 2nd picture is 1-2m ...
1
vote
2answers
76 views

Cropping aerial image using Python?

How can I crop an area from an aerial image knowing the latitude and longitude of the image's corners and also the cropped section? I have a LiDAR scan and I and want to crop an image overlay to fit ...
4
votes
0answers
45 views

How to compare two sets of points in QGIS?

I have two point layers with XYZ data; one set are points measured in the field and the second set is a Lidar data set. I want to check the accuracy of the Lidar in comparison to the measured data. ...
2
votes
2answers
40 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 ...
19
votes
2answers
2k 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, ...
2
votes
0answers
36 views

What are definitions of watershed segmentation, local maxima, variable window search, etc (about 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. ...
1
vote
1answer
108 views

Analyse slope gradient from LiDAR .asc data

I'm new to using QGIS. I have purchased some LiDAR data which downloads as .asc format, is there a way to analyse the terrain slope angle from this data or does it need to be converted into DEM? ...
15
votes
11answers
23k 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 ...
3
votes
2answers
79 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 ...
4
votes
3answers
520 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 ...
6
votes
1answer
571 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 ...
1
vote
1answer
35 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 ...
2
votes
1answer
32 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 ...
2
votes
2answers
112 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 ...
1
vote
2answers
124 views

Lidar and infrared data to detect petroleum releases

Would this combo detect differences in soil temperature in proximity to the release due to the higher temperature of pipeline fluids or would the surface temperatures be affected by the volatilization ...
3
votes
1answer
43 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
votes
2answers
294 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, ...
2
votes
1answer
129 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. ...
5
votes
1answer
3k 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
57 views

How to interpret Lidar scan line problems?

I am calculating various gridmetrics using the Lidar processing tools in FUSION. The dataset I am working with contains 154 flight lines of high density data, at a nominal pulse spacing (NPS) of 1.5 ...
7
votes
1answer
199 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). ...
9
votes
2answers
235 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, ...
11
votes
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 ...
2
votes
0answers
66 views

Cloud points metrics with Terrascan

I need to extract from a las file statistics like percentile 95 height and others. Do you know how to do it with Terrascan? I can do it with FUSION, but I would like to do it with Terrascan.
3
votes
3answers
116 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 ...
1
vote
1answer
241 views

ArcPy error: Add Feature Class to Terrain. [closed]

I'm writing a script to convert lidar data (in .las format) into a terrain without going through all the clicking and so I can send it out to neighboring states with similar programs (I'm using ArcGIS ...
2
votes
1answer
70 views

Las 1.2 format displays extremely long thin line of points

I am having difficulty properly visualizing aerial LIDAR data from the following source: http://csc.noaa.gov/htdata/lidar1_z/geoid12a/data/1124/ Taking any of the laz files, the point cloud displays ...
0
votes
0answers
28 views

Opengeo and Ubuntu memory issue

I was working with LiDAR in Opengeo suite while following the Boundless tutorials (http://workshops.boundlessgeo.com/tutorial-lidar/) In my recent post titled 'LiDAR and Opengeo', I mentioned about ...
8
votes
4answers
1k views

How to view LiDAR data from a 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
6answers
838 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 ...
2
votes
1answer
73 views

Lidar and Opengeo suite

Opengeo suite has provided a tutorial on how to manage LiDAR data using postgresql. I was trying to follow the tutorial in this link (http://workshops.boundlessgeo.com/tutorial-lidar/). I am new to ...
0
votes
1answer
84 views

Point cloud LiDAR

I have been trying to grid a point cloud, version1.2, LiDAR datasets which are intended to be used for hydraulic simulation of flood propagation. Already, I have used Arc* to work on the traditional ...