Linked Questions

9
votes
2answers
1k views

Retrieving heights of buildings using remotely sensed data (except lidar)

How can I get the height values of buildings from a certain sector a city without going into the field to collect data? Is there anyway to do via satellite imagery, SRTM, ASTER GDEM or any DEM for ...
7
votes
2answers
361 views

Improve DTM under forested areas without smoothing?

I'm using a DTM retrieved from LiDAR data and I noticed that forested areas are grainy or not defined. The DTM data was retrieved from geostore.com. Here is one example: Is there any way to directly ...
2
votes
2answers
318 views

Getting a flat surface from DSM for height calculation?

I have a DSM done trough photogrammetry with the software Agisoft Photoscan of a forestry experiment and I need to accomplish an analysis of the mean height from it. My problem is that the profile has ...
2
votes
2answers
6k views

Interpreting .ASC/LiDAR Data?

I'm a complete novice to the world of GIS. I'm involved with a project which requires LIDAR data to be imported into CAD software. When I go to the geostore, which contains LIDAR survey data ...
2
votes
2answers
408 views

Pixelated DSM using LAS Dataset to Raster?

I am using ArcGIS 10.2.2, and I am trying to create a DSM out of some LIDAR data. After checking the LAS Dataset properties, I see that I have an average point spacing of approx 0.3. I tried ...
6
votes
1answer
1k views

Calculating shadow of trees with DEM in QGIS?

I have a DEM with a good precision (0,5 x 0,5 m/pix LiDAR) and I´m looking for the way to obtain a raster (or shapefile) with the shadow of the trees located in that place for a whole day (ideally ...
4
votes
1answer
3k views

DTM extraction of tree heights

I need to classify tree heights in a DSM of a slope-y terrain. It´s not a forest but several individual / detached trees. In a plane terrain it won´t be an issue but in that uneven terrain I need ...
2
votes
1answer
2k views

Why ground model from point cloud in Global Mapper is inaccurate?

I have a LAS file that I assumed was based on LiDAR, but it is actually based on ADS (airborne digital sensor) imagery, according to the body that captured the data. I load the file in to Global ...
1
vote
1answer
96 views

Generating DEM Generation in LPS?

I have a Cartosat 2.5 m Imagery and Block files along with DSM Data. I wanted to generate DEM using Leica Photogrammetry Suite Software. Does anyone know the steps of generating same? I have to edit ...
1
vote
1answer
877 views

Generating Canopy Height Model (CHM) with Quick Terrain Modeler?

I currently looking forward to process LiDAR point clouds (forest data) using Quick Terrain Modeler (QTM), but is it possible to create Canopy Height Model directly using the software?
1
vote
1answer
71 views

Checking Vegetation height accuracy in urban areas

I have digitized vegetation as polygons covering the canopy of trees in urban areas. Are there any suggestions to check the accuracy of height. I have been manually validating with visual checks, ...
1
vote
1answer
384 views

Difference in the elevations for the same building on two DSMs saved in *.asc and *.laz formats

The following question concern the same type of data as the one I've asked in Differences in the longitude and latitude between a LiDAR DSM and an optical image. Basically, I've downloaded a tile of ...
1
vote
1answer
12k views

Creating Digital Terrain Model from Digital Elevation Model using ArcGIS for Desktop? [closed]

I have a DEM and I want to create a DTM from that DEM. Is it possible to do this in ArcGIS?
0
votes
1answer
212 views

how to create a point shapefile with azimuth and elevation?

I have downloaded a GPS almanac file which gives azimuth and elevation for each GPS satellite at a particular latitude and longitude. I want to create a point file with azimuth and elevation angle ...
0
votes
1answer
3k views

What is a DTM in Grid format?

A client asked us for a group of files of DTM in Grid Format. And my question is, what is this DTM in Grid format? O maybe its same of DEM? Is it possible to convert from DEM gray scale format to DTM ...

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