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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2answers
390 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 ...
12
votes
2answers
675 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 ...
1
vote
0answers
202 views

QGIS 1.7.4 crashes when using interpolation tool [closed]

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
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 ...
1
vote
2answers
505 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
75 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
4k 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
168 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
766 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 ...
1
vote
1answer
773 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 ...
11
votes
3answers
2k 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 ...
5
votes
2answers
391 views

Seeking commercial web service for LIDAR/DSM data in USA

I apologize for not knowing all the proper terminology to ask this question. I am seeking a commercial service for providing pay-per-use high resolution elevation data in North America. It must come ...
4
votes
2answers
455 views

Purpose of building footprints

What are the uses (public and private industry) of building footprints? I'm trying to figure out how polygon building footprints can be used. i.e. are they used for determining tax liabilities, ...
1
vote
2answers
309 views

Can REST or the ArcGIS API for Flex read VAT tables from a Raster?

When publishing a bare earth DEM that has a VAT table, or value attribute table "A VAT is a table containing attributes for a grid, including user-defined attributes, the values assigned to cells in ...
2
votes
3answers
828 views

Where can I find the highest resolution shapefiles for counties or states

I am looking for a download source which has the highest resolution (greatest detail/accuracy) for all counties in the US. More specifically I run into this problem mainly when dealing with the ...
6
votes
1answer
1k views

How to display dynamic raster (lidar) data on a Web map?

I have some high quality LiDAR data. I need to process it dynamically, and update a field (not elevation field) depending on my input and elevation at that point. Once this is done, I need to display ...
2
votes
1answer
211 views

Get Cell Value Webservice for ArcGIS Raster (LiDAR) without using ArcGIS

I want to expose the getCellValue function on Lidar Data, as a web service. But I don't have access to ArcGIS (server or desktop). What options do I have to fetch cell value, given lat lon, from a ...
6
votes
3answers
474 views

Grass v.rast.stats returning null values

I have a vector layer (polygon) and a raster layer. The raster layer holds values for height above bald earth in a field called "value". I'd like the vector layer to inherit either the mean or the ...
1
vote
1answer
479 views

LIDAR data for Chicago

Is there any public or private sources of LIDAR data for the city of Chicago? Searching online has not lead me to any sources, and I am unsure how the commercial world of LIDAR works. The LIDAR point ...
1
vote
1answer
167 views

How to display Lidar Data in ee0 (Interchange File) on Maps

Hi I have Lidar data in ee0 files (interchange files). Can i ovaerlay them on some maps like say Bing Maps or Geoserver with Open Layers? If yes whats the right way of doing it? Thanks
2
votes
2answers
328 views

Where I can find real world data for triangulation?

I want points for practicing triangulation algorithms. Just points with coordinates [X,Y] and elevation [Z] of real world terrain. I can use Google Maps Elevation API, but there is no method how to ...