Questions tagged [gdaldem]
Tools to analyze and visualize DEMs under the GDAL umbrella. Operational since GDAL 1.7.0. It has 7 different modes hillshade, slope, aspect, color-relief, TRI (Terrain Ruggedness Index), TPI (Topographic Position Index), or roughness.
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How to pass options in Python GDAL binding?
I am trying to color a GeoTIFF file and convert it to PNG. Several thread (1, 2) have pointed the gdaldem function. Here I am now porting the function to Python. Using the documentation, I can pass ...
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How to use GDAL with Python to make a GeoTIFF file smaller?
I have a GeoTIFF elevation DEM raster file with x & y dimensions of 32,412 each. I'd like to reduce the dimensions of the file x & y dimensions to 14,142 without cropping or losing any more ...
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Convert EPSG and vertical datum of a DEM file
I have DEM files that are in EPSG:4326 - WGS 84 and use latitude and longitude for coordinates. The elevation units are in meter but use the WGS84 ellipsoid with WGS84 elevation. I want to convert ...
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What is cell neighborhood size in gdaldem?
I would like to know the cell neighborhood size used in some of the utilities in gdaldem. I can't seem to find them in the documentation. For example, TRI has per definition 8-cell neighborhood size, ...
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30m SRTM DEM is displacing incorrectly with coordinate range error in QGIS
I am trying to import DEM data to QGIS.
Firstly, I have downloaded it from https://dwtkns.com/srtm30m/.
For instance, I have N35E117 here in QGIS with corner coordinates:
Corner Coordinates:
Upper ...
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In gdaldem: NODATA value in GeoTIFF found in earlier version but not recognized in GDAL 3.4.2
I'm not sure if this is something that has improved in GDAL or something that could/should be fixed. I have a particular GeoTIFF here that has values (-32767) that are supposed to represent NODATA ...
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Problem with gdaldem slope -> result is off by some degrees
We are currently having some issues with gdaldem slope. We'd like to create a slope map of a geotiff, but the result seems to be some degrees off to what it actually should be.
Our input geotiff is in ...
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Use BIGTIFF=YES creation option. NOT WORKING
I am busy trying to merge 62 DEMs (totaling in 5.6 GB and in GeoTIFF format) in QGIS 3.18 to create a single DEM of southern Africa. The problem was that the tiff I was trying to generate was larger ...
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Generating vector slope maps using GDAL
I have a DEM file that I created a slope map of using gdaldem slope. This works fine and if I view and colorize it, I can now see how steep a hill is but now I'd love to create a shapefile out of that....
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gdaldem - raster to RGB raster with color-relief
I have 6-layer raster with float value.
I have six different QGIS style with color value.
Here is image value from QGIS:
Here is a QGIS style (for 6 layer):
<!DOCTYPE qgis PUBLIC 'http://mrcc.com/...
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Creating color relief from GeoTIFF using gdaldem returns font name
I'm trying to generate a color relief map from a SNODAS greyscale geotiff file scaled from 16-bit to 8-bit. Given the type of data and the scaling, it seems the pixel values are set at 1-5, with 5 ...
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Making color text file using GDAL
I have an 8-bit greyscale image that I want to convert to a "heat map" based on data values (0-255), using a color ramp. I'm aware that gdaldem works with color-relief, so I used the ...
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PNG driver chokes on raster gdal_transformed to ot byte
I'd like to extract a part of a DEM (data.linz.govt.nz wellinton lidar dem) and analyse it using gdaldem:
$ gdalinfo /vagrant/public/assets/GeoTIFFs/17a17d1fae/lenz-mean-annual-temperature.2193.tif ...
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How to open a .dem file properly?
I have this DEM file downloaded from the internet. It's a text-formatted file and it looks like this:
1440 720 30 -9999 450
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -...
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GdalDEM slope error in Jupyter
I try to calculate slope data. This is the DEM source https://www.earthenv.org/DEM
Firstly, I translate data with gdal.Warp according to image UTM zone. Original image .bil extension so first I ...
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Raster antialiasing
I am looking for a way to antialias integer DEM data (hgt file) to float GeoTIFF. That way I want to avoid gdaldem hillshade artefact lines which you can see in this picture:
I don't want to blur ...
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ETOPO1 upsampling issue
I am using the OSGeo4W Shell with the ETOPO1, 1 arc-minute global bathymetric data (etopo1_ice_g_f4.flt).
I am cutting 256x256 pixel slippy map tiles, and am having a problem with getting smooth-...
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Colorize singleband GeoTIFF raster using Python/GDAL with discrete interpolation like in QGIS
I have singleband raster with min 0 and max 0.82 values.
For raster I applied next color scheme in QGIS:
I want colorize raster using GDAL command, but receive raster with another color:
GDAL ...
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QGIS/GDALDEM SLOPE Output Has Contoured Or Terraced Texture
I have been trying to greatly reduce or eliminate the contour-like texture that appears in my output from gdaldem slope. The image, below, demonstrates this textural effect.
The texture of the ...
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Using gdaldem to match cumulative count colouring of QGIS?
I am trying to colour a single band grey raster (NDVI) using gdal to match the same colouring when I bring the raster into QGIS and colour it with a cumulative count cut (2%/98%). When I use the code:
...
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making Color-relief from a rasterfile
I have a tempreture raster file, its min value is -125 and it's max is 50 I want to make a color-relief file of this raster,
I tried to use gdaldem to make it. It works but the problem is with its ...
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gdaldem -alpha flag in Python bindings is missing
I've been trying to get the python bindings to work in order to keep the processes in memory, making it faster.
I have previously used:
subprocess.call('gdaldem color-relief file1.tif -alpha hramp....
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GDALDEM hillshading running slow?
I have, for a while, been trying to make a terrain map using NASA's SRTM 3 dataset. I have a large (13 GB), geotiff projected to web mercator of all the elevation files provided. I have been able to ...
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Losing resolution of my DEM/TIFF when converting from HGT
I need to get a nice hillshade from this area. My steps:
1) Get HGT files from the area:
-- phyghtmap --download-only --a -43.7544:-23.2363:-42.0378:-22.3183 --earthdata-user=myuser --earthdata-...
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Python subprocess.call gdaldem module
In python how do I subprocess.call the gdaldem module for color relief?
In the command line I would type this:
gdaldem color-relief path-to-raster path-to-colorfile path-to-destination-raster -alpha
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gdaldem slope....odd values, almost all 89.98+/- (? - why?)
I'm passing an SRTM1 3601x3601 file to "gdaldem slope".....I've queried the values in Python, they are reasonable (min 222, max 424) for an area of SW Iowa. Took a bit to get the syntax right, but ...
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gdaldem slope calculation noData
I use gdaldem to calculate the slope of a given region. This is the command I use:
gdaldem slope -s 111120 -p -compute_edges N34E069.hgt N34E069_slope.tif
(I've got the SRTM data from http://...
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gdaldem exact color matching fails
I'm using gdaldem color-relief to read a Uint32 raster and write an RGB tif. The input color_text_file has one line:
102216130 23:105:102
My input file is a single (large) pixel of value ...
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What is the meaning of -32768 in gdaldem color config?
I found a gdaldem color config:
3500 140 140 140
2500 209 209 209
1500 225 225 225
700 245 245 245
0 252 252 252
-32768 213 232 237 <=== What mean -32768
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gdaldem hillshade using command to calculate hillshade of whole folder [closed]
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.
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getting strange "grid" artifacts when creating hillshades using gdaldem
I'm trying to create hillshades from Czech elevation data (Fundamental Base of Geographic Data of the Czech Republic (ZABAGED®) - altimetry - grid 10x10 m) - a demo files is available here: http://...
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gdaldem hillshade stop working with new projection?
Parallel to gdalwarp `-te -5.8 41 10 51.5 -ts 1980 0` not working with mercator? , my hillshade works with lat/long input :
gdaldem hillshade input.tmp.tif shadedrelief.tmp.tif -s 111120 -z 5 -az ...
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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 cloud.
...
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hillshade and slopeshade geotiffs fail to convert to new projection using gdalwarp [duplicate]
I'm trying to convert my three DEM products (colour, hillshade and slopeshade; the latter two generated using gdaldem) from EPSG:4326 -> EPSG:3857 using gdalwarp, via the command:
gdalwarp -of GTiff -...
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How to extract drainage network through gdaldem
From gdaldem I can view slope, aspect, and hillshade maps.
"gdaldem slope manj.tif ouoi.tif -p -s 60"
"gdaldem aspect manj.tif gg.tif"
"gdaldem hillshade manj.tif hh.tif"
Is there any command to get ...
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gdaldem slope attribute passing
How to pass slope attribute to the command
"gdaldem slope manj.tif outpiu.tif -p use percent 45 -s 111120/370400"
It's giving error like FAILURE: Too many command options.
give any ...
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Improve gdaldem hillshade output (lighten up flat parts)
I have a hill-shading that I made using gdaldem hillshade which is already pretty good. I used the option -alt 60 to get nice contrast, but the problem is, that with lowering the light-source, also ...
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Going from hillshade to percent shaded using gdaldem?
I assumed hillshades output percent shaded (scaled to 255) at the given azimuth and altitude but this is incorrect. A flat raster at 80 degrees altitude has a maximum value of 251 instead of 255. How ...
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gdal2tiles.py generating dark tiles from .img file
Dark tiles are generated when I run gdal2tiles.py on a .IMG file(a scanned and georeferenced topographical map).
This question advised to apply a color relief map using gdaldem before generating ...
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How can I specify the ranges in the gdaldem's color configuration file?
I want to render an IMG file according to a specific renderer, and export to a jpeg File. I have asked a question about this, and got a satisfactory answer.
The issue now is that I need to write a ...
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