Digital Elevation Model (DEM), which could be a Digital Terrain Model (DTM) or a Digital Surface Model (DSM).

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3
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1answer
182 views

Choosing the right parameters to interpolate a DEM from contours

I have a 5 meter interval contour lines feature class which I would like to interpolate to a DEM. I am well aware of at least 2 tools ("tin to raster" and "topo to raster") which can help me with ...
1
vote
1answer
27 views

In qgis2threejs html output select deselect the layers not working

I used qgis2threejs to output 3d model with a dem and another viewshed output. I want to tick untick the layers for displaying and not displaying the layer.But the select unselect option in right ...
3
votes
1answer
2k views

Determining if DEM has z values?

How do I know if the DEM contains z-values? I am looking at the DEM's layer properties and it does not mention the z values. I then add it to ArcScene and tried to find it without success. It ...
15
votes
10answers
31k 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 ...
1
vote
1answer
48 views

Bathymetric-topographic DEM color relief?

I am using QGIS 2.12 on a Macbook Pro running OS X 10.10.5. I have an interesting DEM for the California coast (which I downloaded from Santa Barbara, CA 1/3 arc-second MHW DEM. I've been playing ...
1
vote
1answer
72 views

Slope analysis of DEM in QGIS?

I have very strange problem with the raster analysis. I have a DEM as a Geo tiff and I do a slope analysis in QGIS. I've done this many times and everything was ok but this time I received reversed ...
1
vote
0answers
40 views

Turning simple raster file into DEM?

I'm using QGIS LYON 2.12.1, and I want to turn a plain gray scale raster file (that I got from Google search) into a DEM. The aim is to apply the DEM (terrain models) function to the newly created ...
1
vote
0answers
21 views

How to create a numerical mask file with the elevation points of an area with QGIS

I'm using QGIS and I have to create a mask file (.txt) as an input for a hydrological model. The file should be a numerical grid map that represents the elevation points of a catchment area, like the ...
7
votes
3answers
539 views

Filtering out canopies and buildings from DSM to have a bare earth elevation

Can anyone suggest methods in filtering out trees and buildings from a DSM so as to come up with a reliable DEM? What I have is a grid from a LIDAR data (.tif file, with 1m resolution). I was going ...
6
votes
2answers
690 views

How to de-noise a DSM

I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any ...
1
vote
1answer
90 views

SRTM DEM and satellite DEM fusion

I have a SRTM DEM and a DEM derived from satellite (Cartosat). Both the DEMs are registered perfectly. Now I want to carry out a DEM 'fusion' process to derive a higher quality output DEM. I am not ...
3
votes
1answer
78 views

Calculate Volume over sloped ground in GRASS GIS

I am trying to do some volume calculations on a DEM with GRASS GIS. However, I believe r.volume measures everything from 0. The ground underneath the pile I'm measuring is sloped. I would ...
3
votes
1answer
82 views

How to exclude water during contour generation?

I recently acquired a LiDAR data set that included a 1 meter DEM. I generated 1, 2 and 5m contour layers but I am seeing a lot of contours within water bodies. I suspect this is either caused by wave ...
6
votes
1answer
144 views

DEM from contours

I have problem to create a DEM from contours. I know it is very simple but I can not make it work. I tried everything but nothing has happended! The shapefiles I've got are a con_lin and a con_pol ...
0
votes
0answers
23 views

QGIS problem with converting TIFF-DEM to ASCII

I converted a .tiff DSM into an .asc file. The output-file is stretched increasingly from th the upper to lower part (the dark structure under the classified DEM is the .asc-file). What went wrong? ...
4
votes
1answer
102 views

Obtaining sink morphometry from local minima points

I am working on LiDAR data from GIS and R and I want to extract landforms from the DEM. I have found a method to obtain local minima points of my LiDAR data. However, I would like to obtain the ...
3
votes
0answers
76 views

Add a dam to DEM in ArcMap

I followed the instructions how to build a dam by whuber (How to build an artificial 'dam' across a river?) "draw a line segment" "compute the Euclidean distance to this line segment" ...
10
votes
2answers
3k views

How to build an artificial 'dam' across a river?

I have a DEM. Created all files related to watershed including accumulation, direction, streams etc... I'm stuck creating a dam. I request you to please let me know how to build an artificial 'dam' ...
0
votes
0answers
11 views

Error : LayerRasterRead failed : Imagine Photogrammetry

I'm using Imagine Photogrammetry ( ERDAS ) and I would like to generate a Data Elevation Model DEM based on PLEIADES imagery. When I execute erdas , it seems like he is computing the DEM but after ...
4
votes
2answers
784 views

Retrieving average building height in urban areas

I am looking for a way to collect data on the height profile of some cities over time. I don't need to produce a detailed 3D reconstruction of cities, nor do I need to detect and measure individual ...
3
votes
1answer
34 views

Help with Rastercalculator - Filter areas with a certain height difference

I'm struggeling a little bit with the rastercalculator tool of QGIS. At the moment I am working with a DSM and a DTM. My aim is to filter all wind turbines out of the DSM and replace it with the ...
2
votes
1answer
71 views

How to find a point with highest elevation in area using ArcObjects

Is there a way to find a point with highest elevation in specified area by using ArcObjects? Let's say that I have a raster with DEM and I would like to establish some areas of interest in this ...
0
votes
0answers
32 views

DEM and r2stl() distorted models?

If I import a dem file into R and then call as.matrix() on it, I can access z values. I want to create a 3D model, but I'm getting strange results. Most of my dems are spiky and if they are smooth I ...
1
vote
1answer
30 views

Converting DTM data to STL?

I'm new here and was wondering if anyone could help? I'm looking to make some 3D maps using DTM data but need to convert it into .STL format for my MasterCAM to read so that I can generate the CAD ...
11
votes
4answers
7k views

Burning stream network into DEM layer using ArcGIS Desktop?

I am working on a DEM that in an area where there is little relief. I would like to 'burn' the river network into the DEM so I can calculate flow accumulation and flow length accurately. I am ...
1
vote
1answer
76 views

Making DEM from contours without elevation data?

I got a shapefile with contours, but no elevation data is present. We can assume as known info, that the contours mark elevations at known steps (say, 20 m). Is it still possible to restore the ...
1
vote
2answers
121 views

Determining Min and Max elevation in Python using GDAL? [closed]

I have a DEM file and shape file of specific area ,and i want to Create a module in Python that writes name of each area which is shows in the picture, with the greatest differences in altitude on ...
1
vote
0answers
32 views

Why does the flow direction tool in ArcGIS desktop give wrong output (unique values from 1-255)?

I ran the flow direction in ArcGIS, and received unique values ranging from 1-255. I know that these values are wrong, and should be along the lines of 1, 2, 4, 8, 16, etc multiples. The DEM is ...
0
votes
0answers
29 views

Aster DEM damaged file (N30 E041)

I tried to merge several raster data sets ( from Aster GDEM), but one file is possibly damaged and I get a hole in my raster, see here ...
1
vote
2answers
78 views

“ERROR 010214: Unable to read STA of…” while running Arc Hydro Geoprocessing Tools

Today I tried running the Combined Terrain with Unknown Sink and Stream Locations Tool from the Arc Hydro Toolset (version 10.3.0.58, ArcMap 10.3). As input I used a DTM with values between -10 and 19 ...
7
votes
3answers
243 views

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

I´m trying to extract DEM and DTM from a LIDAR file. Currently, I rasterize the image but don´t know which algorithm I need to apply to obtain the DEM and DTM information in different models to be ...
2
votes
0answers
14 views

Applying colour ramp to DSM in ArcGIS using real elevation values as colour cut-offs?

I have a topo-bathymetric lidar DEM that I need to construct a CSR for in ArcGIS 10.3. I know how to make colour ramps and personalize them, but I'm wondering if it's possible to make a ramp based on ...
3
votes
2answers
1k views

Using Phantom 3 Pro to capture aerial imagery for small site plans and derive DEM?

I am curious if this consumer UAV can be used to capture imagery for further processing to stitch seamless imagery and to use as input into stereo/photogrametry software to create reasonably accurate ...
0
votes
1answer
21 views

DEM data to Excel using ArcMap?

I have downloaded a DEM from digmap and have opened it in ArcMap. I now want to transfer elevations from each gridsquare into excel to be used in a water routing model. Do you have any ideas how ...
0
votes
2answers
78 views

How to create a reservoir for a dam site?

I have created the watershed for a proposed dam site point using SRTM 90m DEM. Now my task is to create a reservoir or pondage where water would be collected from the watershed. Above a watershed can ...
0
votes
3answers
115 views

Why is my DEM in ArcScene flat, not 3D?

I am working with Digital Elevation Models in format TIFF 2km * 2km. As far as I know DEMs should have a 3d function but in my case the DEMs are flat. They only look 3d because of the hill shading. ...
1
vote
1answer
40 views

Regarding Atmospheric correction and Elevation DEM Projection system

I am trying to conduct atmospheric adjustment of Landsat 8 image bands using 6s algorithm (i. atcorr grass gis tool). It seems, in the input section, an elevation raster map should be provided. In my ...
1
vote
1answer
45 views

Creating contours from DEM for multiple files using ArcMap ModelBuilder?

How can i create an ArcMap model in ModelBuilder to iterate through a folder and applying contouring tool on all tif DEM files on that folder.
0
votes
1answer
29 views

gdaldem hillshade using command to calculate hillshade of whole folder

I need to calculate hillshade of folder using gdaldem hillshade which has 60 files in it. How can i do it using command prompt window.
2
votes
0answers
38 views

Fixing undesirable lines between tiles from SRTM contour line extraction?

I'm trying to make a South American topography map based on SRTM data on QGIS. The problem is a visual one. If the topography contours are extracted from individual SRTM tiles, it results a little ...
4
votes
3answers
107 views

Irregular XYZ point data to raster (TIF) - LASTools alternative?

I am trying to convert my irregular spaced point data (xyz) to a DEM and then, to a raster (geotiff). Because of the irregular spacing I need a triangulation first, right (so, no spaces are in the ...
6
votes
2answers
355 views

Simplified flood “model” / estimation from elevation data

The goal is to present an estimation of potential flooded area. But still keeping it simple. I know this will not be accurate. The question is: will it be good enough for at gestimate / rough ...
2
votes
1answer
818 views

Combining DEM raster with vector data in ArcScene?

Ive have a raster layer of earthquake data that includes depth. I also have a DEM file. The problem is that I need to plot earthquake depth relative to the DEM file rather than sealevel in order to ...
2
votes
1answer
48 views

Looking for DTM for Morocco

I am looking for a DTM for the city of Agadir in Morocco. Could anyone help me to find it?
1
vote
0answers
37 views

Calculating flow distance of pixel from outlet using R?

I have created these raster files for a river basin: DEM Flow Direction Flow Accumulation Also, I have another raster with values of rainfall. All the 4 rasters have same spatial extent, ...
1
vote
3answers
181 views

Open LiDAR DEM of the UK with *.asc extension

I've downloaded a tile of a freely accessible LiDAR DEM of the UK from http://environment.data.gov.uk/ds/survey#/download. But I don't know how to open it. The files inside have the *.asc extension. ...
0
votes
0answers
24 views

DEM Mosaic Dataset Processing - Output Surface and Hillshade raster to same extent as input raster tiles

I have a lot of DEM rasters, tiled adjacent to each other. I would like to make a surface and a hillshade raster to the same extent as each DEM tile. Current issue: processing on a tile-by-tile basis ...
4
votes
1answer
71 views

How to calculate an Illumination raster for fire ignition danger analysis?

I am doing a fire ignition danger analysis using this equation that I found in Millington (2012) http://www.jmecology.com/wp-content/uploads/2014/03/33-42-MILLINGTON.pdf IR = 4H + 3V + 2I – E Where: ...
1
vote
1answer
48 views

General guidelines for topographic contour to DEM conversion?

It seems that many different DEM resolutions (10m, 30m, 100m) could be created from a contour map (with, for instance 50m elevation changes marked), but of course some of the resulting DEMs will be ...
1
vote
0answers
49 views

How to orthorectify an image from a hilly region without sensor parameters but with DEM and some GCPs in ERDAS or ArcGIS?

I have a raw raster image from a sensor, but do not have the possibility to obtain the sensor parameters. However, I do have a (older) reference ortho image and a DEM with good accuracy. Both are ...