All Questions
113
questions
1
vote
0
answers
21
views
Elevation discrepancy while clipping a DEM in QGIS 3.28.9
I clipped a DEM (Clipped mask) using the GDAL Processing Tool - clip raster by mask layer from a DEM (clipped).
The maximum elevation value of the Clipped mask is 7286m, while the same in the clipped ...
- 91
2
votes
0
answers
58
views
Getting distance between DEM's zero elevation and earth's center [closed]
I'm using the DHM25 DEM available here:
https://www.swisstopo.admin.ch/en/geodata/height/dhm25.html
EPSG:21781+5728
(Swiss CH1903 / LV03 + LN02 height)
I need to use the earth's radius under ...
- 129
3
votes
1
answer
181
views
Reading GeoTIFF from path and converting it into PostGIS raster data type
I need to read the raster file (DEM) from path directory and turn it into PostGIS raster data type. I formed this SQL query:
SELECT ST_FromGDALRaster(pg_read_binary_file('D:\dems\img.tif'))
FROM ...
- 43
0
votes
0
answers
161
views
Vertical transformation of DEM from NAVD88 to CGVD2013 datums
I am attempting to recalculate a DEM raster from the vertical datum of NAVD88 to the 'new' Canadian vertical datum, which is CGVD2013. I've looked at a few similar questions but they only are geoidal ...
- 143
0
votes
0
answers
92
views
Contours of a DSM render slowly
I am comparing two digital surface maps (dsms generated from drone photogrammetry) taken at two times. The contour lines render quite quickly for one (in seconds) and quite slowly for the other (1–2 ...
- 83
2
votes
0
answers
111
views
Calculating slope-adjusted surface area from DSM
Is there a (simple) way to calculate the surface area from a regular DSM raster considering the slope/aspect? In my case I've got a DSM (0.5m resolution) with a building, I would like to calculate the ...
- 21
1
vote
0
answers
395
views
Run gdalwarp to rectify a raster (RPC embedded) with DEM but got error: Too many points failed to transform, unable to compute output bounds
I've been trying to rectify an unprojected raster (with RPC model) with digital surface model (DSM) by using gdalwarp command. Here is the command:
gdalwarp \
-co BIGTIFF=YES \
-co "TILED=YES&...
- 258
0
votes
0
answers
452
views
Vertical transformation of DEM from EPSG:3035 to EPSG:4326
I am trying to convert a DEM file from EPSG:3035 (ETRS89-extended / LAEA Europe) to EPSG:4326 (WGS 84) with gdalwarp. EPSG:3035 uses the European Terrestrial Reference System 1989 ensemble datum where ...
- 329
1
vote
0
answers
83
views
Setting negative DEM values for the sea and water bodies to zero
I've downloaded a few of the Cartosat-1 CartoDEM Version-3 R1 files from BHUVAN (https://bhuvan-app3.nrsc.gov.in/data/download/index.php).
The files seem to be in the WGS84 format and have values of -...
- 43
1
vote
1
answer
114
views
Calculating terrain attributes before or after upscaling DEM
This is more of a theory question. I am working on a project that requires the use of topography data, I have a 1KM resolution global DEM to which I will be using GDAL to calculate general topography ...
- 11
1
vote
1
answer
119
views
Flipped Contour Polygons from GDAL
UPDATE # 01 : Links to related past questions:
Mirrored Contours from DEM in QGIS
gdal_translate creates images that are mirrored
This question has been asked before, but I can't fix my personal ...
- 191
1
vote
0
answers
103
views
Terrain correction in SAR image
I am new to the gdal utility. Using DEM data of the Moon, I am trying to perform terrain correction on SAR images. I have a DEM file and SAR data into tif file format. Both DEM and tif file are in ...
- 83
0
votes
1
answer
444
views
Merging two DEMs of different resolutions
I have two sets of GeoTIFFs (or ArcGrids) one at 2m resolution and another at 1m.
I would like to merge the 1m on top of the 2m, coverage varies over the datasets as seen here for example:
2m coverage:...
- 191
0
votes
2
answers
508
views
Building DTM using GDAL
I want to build a DTM.
I have extract the ground points from DSM raster by slope base methods and saved in to a raster.tif file.
Now I'm trying to extract ground points from raster.tif as GDAL dataset ...
1
vote
1
answer
3k
views
Rotating raster using Python [closed]
I am trying to rotate a DEM raster (NetCDF file) using Python language, but there is still no progress. I have tried GDAL Python but not so much information in the document about rotation. Do you know ...
- 67