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

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0answers
47 views

Managing or Reducing noise in a mosaic raster

I have created a raster with the Mosaic to New Raster tool from 3 separate rasters. However in my mosaic I have some consecutive pixels which seem to be the noise of the previous procedure. Is there ...
1
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1answer
47 views

Proof low deviations in DEM compared to point dataset

I am not sure how to achieve the following consistently: I have a regular distributed point dataset (surface elevations). From this I derived several DEM using QGIS IDW Interpolation method. Now I ...
3
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1answer
146 views

Creating constant slope DEM using ArcGIS Desktop?

I wanted to create a DEM of constant slope say 1/3000. How can I proceed in ArcGIS Desktop 9.3? The area may be 1000m x 1000m or any other as per convenience.
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0answers
37 views

How do I make a constant slope elevation model in arcMap? [duplicate]

I am currently working with ArcMap to develop an elevation model of a quarry showing how the terrain at the quarry site would look post-closure. One of the requirements is that the slopes placed along ...
0
votes
1answer
66 views

DEM data processing

I downloaded ASTER GDEM Tiles and mosacked them in ENVI. After that I exported the Mosaic in tiff format and I opening it in Arcgis, the image is gray all through but the pixels are showing correctly. ...
9
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4answers
1k views

Are there any open source tools to detect and fill sinks on a DEM?

Are there any open source or inexpensive tools to detect and fill sinks on a DEM? ArcGIS Spatial Analyst is just out of my price range.
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2answers
753 views

min and max values are not correctly calculated for DEM

I'm working with DEM in QGIS and need to know the min and max values of my data. In the Properties window, under the Metadata tab, the statistics section shows such values. However, I usually find ...
1
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2answers
75 views

Where do I get Elevation Data for Scotland?

So I am new here and I arrived here because I have been searching for quality elevation data for the entire Scotland but I have not succeeded yet. Kindly help if you know where to get the data Raster ...
1
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2answers
88 views

Simulate sun movement

Are there any software packages/solutions that allow me to simulate the movement of sun or direction of sunlight over a period of time (e.g. 24 hours)? My purpose is to determine the regions cast in ...
2
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1answer
72 views

Unable to Produce Hillshade

I have been trying to create a hillshade using DEM data, however, regardless of the scale and z values I use the output is all black. I accessed the DEM data from a government source and clipped it ...
2
votes
1answer
92 views

How to calculate point(or XY) for Start point of Slope and Endpoint of Slope along the Section line on DTM

How to calculate point(or XY) for Start point of Slope and Endpoint of Slope along the Section line on DTM. for instance
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0answers
21 views

edit tif from dem by polygon selected in arcmap

i need to edit the tif of dem generated from agisoft photoscan using the arcmap to do a slope map from area. how to select the pixels and change their altimetry information mainly in trees locations ...
6
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1answer
7k views

Which is better, DEM or Triangles (TIN/Terrain)

Which is better DEM or TIN? What are the benefits/negatives of each?
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0answers
52 views

Surface Volume 3D Analyst tools

I'm using Surface Volume tool (ArcGIS 10.3) to calculate volume of air from a valley. I delimited my DEM (clip tool) and choose Below as plane reference with 603 m as height. The DEM is projected in ...
2
votes
1answer
37 views

How do I count the number of cells which can see each cell in QGIS

For each cell in a DEM I'd like to count the number of cells which can see it (i.e. direct line of sight) - Can anyone explain how to do this in QGIS? Thanks,
8
votes
5answers
2k views

How to aquire a topographical map of Britain?

First of all, let me say that I know next to nothing about GISs. I'm trying to find / make / aquire a topographical map of britain. I want to use it as a height map in Dwarf Fortress so it needs to ...
0
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0answers
21 views

What is the best option for web elevation profile using in-house DEM?

ArcGIS Server requires the advanced license for the 3D analysts extension. Are there any open source options? Thanks
-1
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1answer
184 views

Create a DEM with 1 foot contours

I have Lidar data which contains multiple .las files for an entire quad. I have figured out which .las is the area I am looking for. I was told the data is in 1.4 meter resolution and would work to ...
2
votes
1answer
74 views

Make a ground mask raster with the Greater Than tool

I'm trying to see if I can replicate the Esri solar suitability site example from this article. I fail on the creation of the binary ground raster. I have made a Bare Earth raster from LiDAR ground ...
0
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0answers
89 views

Mosaic to New Raster: Problem with min and max values

I have to combine several DEM rasters into one from this source: http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp, so I use Mosaic to New Raster tool. I set up the tool: 1) I input the rasters (all ...
5
votes
1answer
4k views

Download new SRTM 30 meters

I read about the new version of the digital elevation model at 30 meters (SRTM 30 meters), but I can not find from were I can download it. some sources: ...
4
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2answers
324 views

What is the source of horizontal and vertical striping in USGS DEMs?

When processing 30m and 10m DEM data downloaded through the National Map Viewer from the National Elevation Dataset, we noticed horizontal and vertical striping not only in the produced results, but ...
5
votes
2answers
129 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 ...
1
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0answers
184 views

Assessing Flood Hazard Risk Zones using DEM

My Question: What is the best effective way to quickly estimate flood hazard risk areas using DEM data? Ideally I am looking for guidance to move forward and perform this process over large areas ...
0
votes
1answer
67 views

Is there a difference between the two sets of QGIS terrain analysis tools?

Is there a difference between Raster/Terrain Anaylsis and the same features in Raster/Analysis/DEM (Terrain Analysis)? The two appear to do the same types of computations; are they the same or is ...
1
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0answers
42 views

How to ignore certain values when creating profile graph in ArcGIS for Desktop?

I have a statewide DEM I am trying to create a profile of, however the DEM has some areas of widely varying size (bodies of water) where data was not collected and these areas were all filled by my ...
0
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0answers
29 views

automatic extraction of dtm using grass gis

i have generated dsm using erdas lps tool which is in img format. i want to import this file in grass gis and extract dtm. can you please tell me how to input the data , in which format it should be, ...
8
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4answers
6k views

How to use SRTM Global DEM for Slope calculation?

I have downloaded SRTM GDEM (~90 km resolution). I am using ArcGIS 10. I have tried to use spatial analyst to compute for slope. However, I can not compute for the slope. The output values has only ...
1
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0answers
48 views

How to show elevation on mouse hover in QGIS?

I've got a DEM layer and would like to have the status panel in the bottom display the elevation in addition to the mouse coordinate. Can that be done? Using QGIS 2.6.1
0
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0answers
42 views

Library to render 3D DEM?

I am implementing a C++ application to generate DEMs from LAS files, and I want to show a 3D visualization of the DEM (show the terrain model, height differences using colors, contour curves...) Is ...
1
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2answers
75 views

Building DEM of large areas

I am putting together a compilation of 1/3 arc second, and 1/9 arc second DEM data for essentially all of southeastern Oregon in ArcGIS. This surface would be used for geomorphological and geological ...
1
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1answer
76 views

Displaying DEM with real elevation values in ArcGIS Desktop?

I am trying to create a DEM with hillshading map in ArcGIS Desktop 10, but I'm getting the result with scale values between 0 and 254. How can I display the scale with the real elevation values? ...
4
votes
1answer
63 views

Calculation of surface derivatives at the edge of the raster

I was wondering how does ArcMap10.2 calculate surface derivatives (slope, aspect) at the edge of the raster, since the Horn algorithm is used and uses the 8 neighboring pixels around each pixel. When ...
0
votes
2answers
41 views

Not able to load a DEM raster into Spatialite

I am using Spatialite to store a DEM raster with terrain values (GMTED2010 from Nasa). To be more precise, I am using the version: spatialite_gui-1.7.1-win-x86.zip plus rasterlite_load ...
0
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0answers
60 views

DEM data for Borneo island (higher resolution data than SRTM/ASTER GDEM for South East Asia?)

I am looking for high resolution DEM data for Borneo island and am especially interested in Sarawak. Currently I only found SRTM and ASTER GDEM data (normal products from NASA REVERB ...
1
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1answer
38 views

QGIS 2.6.1: “no enhancement” option not working on DEMs

When I import DEM raster layers and try to change the contrast to "no enhancement" I get a blank white image in the map window. Changing "black to white" to "white to black", the map remains a blank ...
3
votes
1answer
139 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 ...
2
votes
1answer
91 views

SRTM DEM with 16 bit signed pixel type changes to 32 bit float when creating slope/aspect/curvature

I have mosaiced 8 SRTM DEM tiles in order to get one raster layer of elevation. When I use "Mosaic to New Raster" tool I set as a pixel type format "16 bit signed" because this is the format that SRTM ...
1
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0answers
52 views

Displaying a Digitial Elevation Model using GRASS GIS draped by an RGB Raster

I have the following: Digital Elevation Model from SRTM LANDSAT Imagery from the same area I wish to display the DEM draped with the raster band combination (3,2,1) using GRASS GIS. My ...
1
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1answer
74 views

Changing the Axis on a Profile Graph

I'm working on a map with forest trails and I want to get an elevation profile of them all individually. I have gone through and interpolated the trail layer with a DEM so that I can use the 3D ...
0
votes
1answer
80 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 ...
6
votes
6answers
810 views

How can I convert a DEM into areas of “flatness”, with an arbitrary fill/cut to area ratio?

I want to find areas of relative "flatness" in a DEM. How can I find flat areas? I want to find a neighbourhood of contiguous cells that have an elevation variance that is within a certain ...
3
votes
1answer
116 views

Correcting for local topography in calculating TRI from DEM in ArcGIS

I'm currently investigating the use of different equipment in calculating TRI from elevation data using ArcGIS. From the methods available ...
2
votes
4answers
196 views

How to calculate RMSE, skewness, and kurtosis of raster image?

I'm doing a project to analyze the impact different interpolation techniques plays on DEM accuracy. In order to do so, I need to calculate the RMSE, skewness, and kurtosis. I have: an original ...
0
votes
1answer
113 views

How to add image(.jpg) to OpenLayers?

This is my website for test: http://www.cv.nctu.edu.tw/shapefile-js-openlayers/ol_simple.html My dem data is (.jpg). var inProj = new OpenLayers.Projection('EPSG:3826'); var outProj = ...
1
vote
1answer
106 views

GeoserverTerrainProvider plugin displays faults in elevation tiles

I try to display elevation data using the triple Geoserver/Openlayer3/Cesium. It seems I have the same problem than http://stackoverflow.com/questions/25936968 and for now, I can not get a working ...
3
votes
1answer
91 views

gdal_grid - fails to find layer and field

I'm using gdal_grid for the first time and get this issue: gdal_grid -zfield field_3 -l layer0 OLEX-LAT-190952014.vrt OLEX-LAT-190952014.tiff ERROR 1: Failed to find layer 'layer0' on datasource ...
0
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0answers
43 views

How to resample a DEM from GCS to UTM with respect to reprojection bounds parameter?

When reprojecting a DEM (e.g., SRTM-derived 1-arc DEM) using PCI Geomatica for example, to constrain pixel size and maintain a square pixel you can either change the image extent or the number of ...
1
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0answers
75 views

How to do a flood simulation without flooding the whole area and covering surface structures (with DEM)?

I have a high resolution DEM and want to do a flood simulation starting at a river. My hope is that the water runs into historical (now dry) river channels (in which I'm interested in) at first and ...
4
votes
3answers
86 views

How to resample a 30m DEM to a 100m slope raster properly?

I need to resample a 30m DEM to a 100m slope raster. Do I just resample the 30m DEM directly to the 100m slope raster? or, do I convert the 30m DEM to a 100m DEM and then create a 100m slope raster ...