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

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2
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1answer
78 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 ...
0
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0answers
30 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 ...
1
vote
2answers
157 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
votes
1answer
138 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
0
votes
0answers
110 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
42 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,
0
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0answers
29 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
11
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2answers
359 views

Understanding min and max values with Mosaic to New Raster?

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: I input the rasters (all ...
0
votes
2answers
600 views

Create DEM with 1 foot contours from lidar data with 1.4 meter resolution

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 ...
1
vote
0answers
59 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
39 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, ...
0
votes
1answer
97 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
vote
0answers
144 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
80 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
vote
1answer
152 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? ...
5
votes
1answer
103 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 ...
1
vote
2answers
113 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 ...
2
votes
1answer
182 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
vote
1answer
40 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 ...
1
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0answers
79 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 ...
0
votes
1answer
166 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 ...
1
vote
1answer
187 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 ...
3
votes
1answer
283 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 ...
3
votes
2answers
259 views

Which method is better for display terrain in OpenLayers?

I want to display terrain in OpenLayers. So, I tried to use dem(.img) and convert it to dem(.jpg) on QGIS. But, the effect is very bad. My expected effect is (This picture is captured from google ...
3
votes
1answer
188 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 ...
0
votes
1answer
278 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 = ...
3
votes
1answer
201 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 ...
1
vote
0answers
68 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
140 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 ...
2
votes
1answer
195 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 ...
4
votes
3answers
177 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 ...
2
votes
4answers
343 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 ...
3
votes
2answers
818 views

GDAL rotate DEM

Is it possible using any of the command line GDL tools such as gdalwarp, etc to perform a rotation of DEM data - a GeoTiff for example? Anyone know how to do this? UPDATE1 After clearing out ...
-1
votes
1answer
65 views

How to decrease elevation values of DEM using open source GIS sotware? [closed]

I am newbie in QGIS, but I was wondering how to decrease elevation dem DEM using QGIS? Can QGIS do that? Or anyone of you can tell me any open source GIS software to perform that?
2
votes
1answer
92 views

QGIS Interpolation on Curved Grid (River DEMs)

Hi QGIS experts out there, I have an very hard task I want to do in QGIS (or another open source GIS program). I have point data for river bathymetry (depth). I have been creating digital elevation ...
1
vote
3answers
326 views

Where can I download a free DEM for Scotland, UK?

I need a DEM file for Scotland, UK. Do you know where I can get it from for free? I need to create a watershed for an area of study. Thanks
0
votes
1answer
26 views

Raster Files Sizes from Point Data Extremely Different

Using ArcGIS 10.1. I created rasters from several groups of point rasters using the Point to Raster tool. All of the points groups are similar size and extents. The first group of points had a file ...
6
votes
2answers
362 views

Burning road network into DEM?

Does anyone have any suggestions for burning a road network into a DEM? I have a python script written up for this executing this in ArcMap, but I would love to hear if anyone knows of any freely ...
0
votes
2answers
62 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 ...
4
votes
1answer
160 views

Convert Whitebox .dep to ArcMap DEM .tiff?

I am having difficulty converting my whitebox raster float file to an ArcGIS raster file in ArcMap 10.2.1 I followed the protocol outlined at: ...
2
votes
2answers
320 views

How to extract elevation values at line start and end points from a DEM?

I am new to the whole gis-experience and need your help working with QGIS. I have: DEM raster with heights (3d) line-shapefile which contains the rivers (2d) I need: heights for "start" and "end" ...
2
votes
1answer
50 views

Disable Mosaic Overview Information When Using Identify Tool

I have a created mosaic datasets using elevation data. When I add this data to ArcMap and use the identify tool it brings up information about both the footprint and image. At full extent the ...
7
votes
2answers
314 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
vote
2answers
117 views

ArcGIS, mosaic first or calculate first

I'm working a set of 30meter DEMs (~40 DEMs) for New England. I've seen a lot of debate on whether to work with (A) the individual DEMs first, and then mosaic the final raster calculations together, ...
3
votes
1answer
217 views

How to subtract out the slope (in general) of a DEM?

I'm searching for a solution process to subtract out the slope of a DEM like this: I have a high resolution DEM and want to reconstruct historical/old/not active parts of a river. The problem is ...
1
vote
1answer
166 views

mosaic dem with multiple coordinate systems

I'm sure this is a basic question, but I'm struggling to mosaic multiple DEMs (~40) into one large raster. The DEMs are 30m NED rasters from the NRCS data gateway, for the New England region. They are ...
1
vote
0answers
365 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 ...
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 ...
7
votes
3answers
240 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 ...
1
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0answers
39 views

findind depression in cloud point and dtm

I would like to find temporary moist areas based on terrain surface shape (depression) directly from cloud point data (ALS) and DTM. Could you help me to find some tools or algorithm to solve the ...