Questions tagged [dem]

For questions about Digital Elevation Models (DEM), Digital Terrain Models (DTM) and Digital Surface Models (DSM)

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3
votes
1answer
532 views

Alternatives to cesium terrain builder?

Looks like cesium-terrain-builder still have this issue and can't be used for large projects, so I wonder if there any alternatives to cesium-terrain-builder that can produce DEM tiles, can work with ...
6
votes
2answers
11k views

Seeking tool to generate Mesh from DTM?

Are there any tools that can take a DTM, in asc or geotiff format and generate a mesh from this that can used in meshlab or similar software. I have asc DTM file that I need to convert to a ply mesh ...
1
vote
1answer
139 views

Hydrological conditioning using stream vector in GRASS?

I would like to make an hydrological conditioning of a DEM using an available stream network in vector form. I know r.hydrodem but it doesn't allow to use the stream vector. I need something to burn ...
0
votes
1answer
62 views

Converting DEM units using Map Algebra and Python

I am trying to write a bit of code that combines a bunch of DEMs that match up perfectly and convert the elevation values of the pixel cells from meters to feet. This is all using Pyscripter and ...
1
vote
1answer
40 views

'Regular Points' vector layer in Bonn

I've downloaded the bonn version of QGIS. Using the 'regular points' vector analysis tool, I've set some 5m regular points over a field so that I can use the x,y coordinates to plot them and measure ...
7
votes
1answer
515 views

Setting the same min/max for multiple raster layers QGIS

I have 268 hgt-files from Viewfinder Panorama that I'm using to create an elevation model, but each of the files has its own min and max-value in Layer Properties - Symbology - Band Rendering. ...
3
votes
2answers
60 views

QGIS Python Discrete ColorBand Classification

I'm trying to automate a process where we bring in a DEM, extract the contours as a new vector layer, then set the dem to render the band between each contour line a separate colour. I want to do is ...
1
vote
1answer
138 views

Modelling fault plane using TIN? [duplicate]

I am working on a project which runs on ArcGIS platform using VB.NET. It is to model a sub-surface fault plane (currently a plane rectangular model with some dip) and then to find required distances ...
7
votes
1answer
232 views

Can LINESTRING “contain” POINT?

According to Wikipedia, The predicates Contains and Within have subtle aspects to their definition which are contrary to intuition. For example,[10] a line L which is completely contained in the ...
0
votes
0answers
44 views

ImageMosaic plugin for DEM rasters on Geoserver

I'm using 30m DEM rasters from the NRCS Data Gateway. I use image mosaic to merge them. But when i preview i see black gaps between rasters. Coverager Parameters: How can i remove that black gaps?
0
votes
2answers
238 views

DEM from Vector to Raster in GRASS GIS

I am using GRASS GIS 7.4 and I have a DEM as points in a vector format and want to turn it into a raster. I tried using v.to.rast and v.to.rast3, but the elevation is not one of the attributes so am ...
0
votes
2answers
56 views

DEM's from Baja, Mexico [closed]

I need to extend my digital elevation map (10m or 30m will do) into Baja from southern CA.
1
vote
1answer
398 views

Efficient downsampling with GDAL?

I have a 350go GeoTIFF file with DEM data for the entire world. (a mix of SRTM, EUDEM, etc. ...) This TIFF file is tiled with a block size of 256*256. I would like to downsample this file to a lower ...
1
vote
1answer
85 views

Generalizing slope raster in Mapinfo?

I am working on calculating a slope raster in Mapinfo using a 15cm DEM derived from a LiDAR point cloud and the output data will have 3 predefined breaks displayed so I need to blur those relatively ...
3
votes
3answers
1k views

Removing las2dem streaks from raster DEM?

I've created a series of DEM files using the las2dem tool from LAStools; however since I don't have a licensed version they have black streaks running across them. Does anyone know a good method for ...
6
votes
1answer
246 views

Line lengths calculation in combination with DEM

I am working in QGIS 2.18.0. I have a problem regarding calculation of line lengths in combination with raster files, to be precise with DEM raster. There is not a problem to calculate the line ...
2
votes
0answers
54 views

World DEM speckled outcome solution

I have a world digital elevation model which has been classified into 5 showing the different heights. My issue is that viewing and printing this image as it is results in a speckled look due to the ...
4
votes
2answers
682 views

Interpolate smoothly nodata values in QGIS

I have a DEM raster where all the buildings have been extruded and now contain "nodata" values. I'd like fill the holes and get a nice and continuous surface (which would approximately correspond to ...
1
vote
0answers
95 views

Edit a raster (DEM) to create a constant slope angle

I'm trying to edit a raster (DEM) that has square sides (90 degrees) to create a surface with a constant slope angle of 18 degrees. I'm working in QGIS and have not been able to find any help for ...
0
votes
3answers
75 views

Changing coordinate of point shapefile in ArcGIS using ArcPy? [closed]

I'm working on coding a function in ArcGIS trying to measure the number of pixels between a point (feature class) and its nearest building horizontally within a UDEM raster, then return the number. ...
1
vote
1answer
223 views

Error running TopologicalBreachBurn in Whitebox GAT

I am trying to execute the TopologicalBreachBurn script in Whitebox GAT. This is my first time using this software so am generally unfamiliar with how it operates. I imported a DEM as an ASCII .txt to ...
4
votes
3answers
870 views

Extract linear features (roads) from DEM

I have a 1x1meter DEM and the original LiDAR point cloud. I need to create a vector feature with roads. Are there any tools in ArcGIS to do this? Or any ideas for the algorithms to try to do this in R ...
11
votes
9answers
24k views

Open source tool to convert a DEM to a 3D model

I would like to convert a DEM (Digitial Elevation Model) file (e.g. from SRTM) into a 3D model that I can then edit with regular 3D modeling tools (e.g. Meshlab/Blender/etc.). However I'm using Ubuntu ...
3
votes
1answer
1k views

Cut Fill Tool in QGIS?

Looking for the equivalent of the Cut Fill Tool in QGIS. I have multiple DSM rasters from a drone that I would like to do a volume analysis on. A cut-and-fill operation is a procedure in which the ...
0
votes
2answers
584 views

r.topidx error: required parameter output not set

I'm calling GRASS r.topidx from QGIS 2.2.0. I can get other tools to work on the DTM, for example r.watershed. But r.topidx I get the Oops message: Oooops! The following output layers could not be ...
1
vote
3answers
1k views

Where can I programmatically download SRTM_V4.1 data?

SRTM v4 is an effort by the folks at CIAT-CSI to scrub, polish, and remove gaps in the raw SRTM data released by NASA (SRTM 3). One userfriendly interface : http://dwtkns.com/srtm/ provides ...
0
votes
3answers
330 views

Equidistance on line contour from DEM

I am using a SRTM 30 meters for slope and elevation. When i'm using this 30x30 rasters to generate contours i set a 30m equidistance for contour, and the results are ok. Now i'm wondering if it's ...
10
votes
2answers
445 views

Cleaning blocks pattern from urban LIDAR (blocks uplifted from streets)

We have a 1-meter LIDAR DEM from a city. A small subset can be downloaded from this link: This screenshot shows raw DEM with gray palette (darker belts are streets, and greyish and whitish ...
1
vote
1answer
400 views

How to open .hgts file from NASADEM data

I have the NASA SRTM1 data as .hgt files from their ftp website, but I would have these elevation data in respect to WGS84. I found by NASA's ftp site a folder named srtmOnly that contains what I want,...
2
votes
2answers
51 views

Flatten broad area through road fill connecting upstream and downstream

What are some recommended approaches for flattening a broad area through a road, as a means of connecting the upstream and downstream parts of a stream bed? I am not trying to connect these areas for ...
1
vote
0answers
88 views

How can I merge a DEM mosaic with an overlapping bathymetry raster (while keeping only the portions of each that I want)?

I am tasked with merging a bathymetry raster with a mosaic raster I created from ArcGrid DEM Tiles downloaded from the National Map, for an areal extent spanning the Coastal Lowlands Aquifer System. ...
1
vote
1answer
501 views

GeoTiff import appears to be flat in BlenderGIS

I an very new to GIS and I am trying to import a GeoTiff file into Blender to view it as a model before importing into unity. For some reason when I import the file into blender as a raw DEM it ...
0
votes
2answers
3k views

Removing black background in ENVI

I am trying to compare two DEM products ASTER and SRTM v.3, but the ASTER has the black background which i think will interfere with my analysis. I don't have access to ArcGIS where I can do this ...
1
vote
0answers
16 views

Points on the opposing side of a breakline

If you have a breakline or even a single line segment within a DEM, how can you tell if two points lie on the opposing side of that breakline or line segment? From a computational geometry standpoint ...
2
votes
1answer
3k views

Handling “illegal data type (Float64)” error when trying to convert .tif to .bil?

Each time I try to convert (in QGIS 2.2) an elevation model from .tif to .bil format a get this error: ERROR 1: Attempt to create ESRI .hdr labelled dataset with an illegal data type (Float64). ...
1
vote
1answer
103 views

Find intersection of multiple DSM's using Python and GDAL

I am quite a beginner in respect to GIS and hopefully someone can help me out with the problem I have. I have multiple digital surface models [DSMs] of the same area with all necessary geo-...
0
votes
1answer
80 views

Elevation shading of linear feature compared to surrounding ground level in QGIS

I have a digital elevation model (DEM - geoTIFF) in QGIS 3.2. There is a linear feature (earth bund/wall) in the DEM that I would like to shade/colour based on its elevation above the surrounding ...
2
votes
0answers
54 views

Adaptive raster to points sampling based on change of slope in QGIS?

I have a high resolution elevation map and need to convert it to XYZ points. Simple conversion generates a lot of points in flat / constant slope areas which are redundant for 3D terrain generation. ...
1
vote
1answer
649 views

Using Color Ramp Manager Plugin in QGIS?

I followed instructions mentioned here and installed the Color Ramp Manager by choosing install experimental plugins as well. Now, when I go to Properties > Style > Single Band PsuedoColor and I ...
1
vote
0answers
588 views

Openlayers in QGIS - Errors in opening google satellite/

End goal: To put contour lines with lat&long layers from a google earth location (Rock Piles beach, HI) in QGIS. I plan to use CRS: EPSG:3760 Does the Plug in (Openlayers / QuickMapServices) ...
0
votes
0answers
26 views

Reduce or heighten a DTM with overlaying polygons

I am using QGIS 3.01. I have a DTM over a historic area. There has been done archaeological surveys there, which suggest that the ground was several meteres below todays surface many hundred years ...
0
votes
0answers
75 views

QGIS DTM loading error

I have downloaded a full set of text DTM's for Northern Ireland from OSNI Open Data, but when I load them into QGIS, some of them do not appear. When I try to load the missing files, I get an error ...
1
vote
1answer
162 views

Changing DEM resolution when creating a slope raster? [duplicate]

I want to create a slope map using a LiDAR DEM. I think that I should use the slope tool; but I need a slope map with a 2m resolution and I'm not sure how to do that. How can I have a slope map with ...
0
votes
1answer
57 views

Extract angle of valley walls on both sides

I have a DEM of a the bedrock surface beneath a glacier and what I want to do is subtract the mean angle of the valley walls on the left and right side of the glacier along this line. I have a line ...
1
vote
1answer
166 views

Blocky Raster from TIN. How to increase resolution?

So i am trying to create a seamless DEM using a DTM created in pix4d with a 5cm resolution (Raster). I have then collected RTK bathymetric data which i have turned into a TIN below To create a ...
0
votes
0answers
178 views

Generate XYZ coordinates of DEM mesh/grid

Is there a way to generate a wire grid of plain text XYZ coordinates starting and ending points for each wire segment? I want to generate them from a digital elevation model. Preferably with gdal/qgis ...
1
vote
0answers
19 views

Adding small-extent rasters to DEM

My goal: create viewsheds for observers which also incorporate the heights of buildings which could block observer view. This is using archaeological data, and is representing time change -- so I need ...
1
vote
0answers
37 views

Obtaining a smoothed DTM?

I am use AcGIS 10.1 and have a DTM with an 8 m grid resolution. Which tool could I apply to smooth the surface?
0
votes
1answer
51 views

Creating a constant surface at designated height above river [closed]

I am trying to create a polygon (and eventually a raster) surface of river deposits that have since been eroded away. We know that at maximum, deposits got up to 600 ft above the present river. Given ...
10
votes
2answers
3k 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 ...