Questions tagged [raster]
Raster is a data format consisting of regular grids of values, usually stored in an image-like format.
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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 ...
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How to get Amersfoort 28992 in QGIS?
I am currently analysing landscape change in the Netherlands, for which I am using maps which have Amersfoort 28992 as their standard CRS. However the most recent map uses Amersfoort 4289 instead.
For ...
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Cell Size in LAS to Raster ArcGis
I want to generate a raster from Lidar data, I was able to generate the DEM with a 0.3 cell size.
Problem is: when I want to create the DSM using the same tool anytime I'm trying to input any number ...
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Data extraction for time series, transform multiple netCDF files to spatRaster with terra in R
I would like to extract data from around 13,000 .nc files to create a time series of temperature global data in R. Each of my files contain a day worth of data of global SST (my variable of interest) ...
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R language, problem with overlaying layers
I must to create a map overlaying several rasters and shapefiles. The rasters inglude the layers "dem" (a digital elevation model), as well as "spA", "spB", "spC&...
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Free and open source solutions for raster data management [closed]
What are recommended ways to manage raster geodata using free and open source software?
Let's say I have a bunch of raster data (mainly orthophotos as GeoTIFFs) on my system. I want to manage these in ...
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Working with raster data for generating Sankey Diagram for landcover changes analysis [closed]
I'm trying to extract from a raster time serie the input data for building this Sankey Diagram on R (or Python). I have 13 classified raster layers (width=1868/height:1637), and I'm trying to analyze, ...
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How to edit a raster band
I am working with several raster layers for which I need to do a post-processing analysis to compare land use over several years. However the raster I am using have over 40 different land use ...
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How to get x, y, slope in raster, in QGIS
I'm the new in QGIS, So I need your help.
I have a slope raster that was made by using DEM 5m (also that was made by using contour 5m shp file).
And I want to get txt(or csv ...) file containing [x, y,...
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Merging many GeoTIFF files give huge space while processing
While I was merging eight GeoTIFF files with each of files has 800MB-1GB of size, on the log of Merge tools in QGIS give me those error, which requires more than 3000GBs of free space. How it can be ...
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Placing JSON data(temperature) without long, lat in OpenLayers
I executed the WCPS query for fetching the raster temperature data in JSON format using the following query:
for $c in (temperature_new) return encode($c[Lat(50:70), Long(30: 60), ansi("2022-11-...
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Resample() function in R's terra package and the r.resamp.interp module in GRASS GIS yield such different rasters
Comparing the results from the resample() function in R's terra package (version 1.7-29), and the r.resamp.interp GRASS GIS module (version 8.2), I find differences in how they apply bilinear ...
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Clip a DSM by raster extent in QGIS
I am trying to clip a DSM by raster extent in QGIS. Both rasters have the same PCS (EPSG: 26911). My results appear a bit off axis from raster extent. Attached a picture; clipped DSM underneath ...
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Elevation Raster cannot be used as Ground source [closed]
I'm new to GIS, especially in 3D. I am trying to calculate the surface volume of a plane below 40m. I cannot get the elevation raster I created from a polygon grid to be used as a ground source, and I ...
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Convert Sentinel-3 LST data in NetCDF format to GeoTIFF format with coordinates using R
I have Sentinel-3 SLSTR LST data stored in different NetCDF files. I know how to extract the Land Surface Temperature, LST, from the Sentinal-3 through the SNAP, but, I would like to use R to work ...
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Lines Visible When Blending Raster Layer of Merged Tiles QGIS
After merging SRTM DEM tiles into 1 raster layer, the layer has no visible join lines on the map canvas as below. Multiply blending mode has been applied
However, when viewed in Layout, there is a ...
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Naming clipped files from layer mask?
I have to clip a quite large raster (corn crops) into individuals rows. It's working fine with the "Clip raster by mask layer" tool with a grid I created.
However, I need the clipped images ...
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Importing raster files EPSG:3035 (ETRS89, LAEA) into R
My knowledge of both R and QGIS is not very high.
I have a problem with the European DEM layer (25 m resolution) downloaded from the COPERNICUS website. The reference system is EPSG:3035 (ETRS89, LAEA)...
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Which resampling method to use when georeferencing with QGIS/GDAL
Using Georeferencer in QGIS (which in fact uses GDAL library), in transformation settings you can define the Resampling method as can be seen on the screenshot. I am wondering on what it depends which ...
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Fastest landscape fragmentation metrics method? [closed]
I have run into very long computation times when trying to calculate landscape metrics for a polygon dataset of 3000 features using large rasters (from 1991-2021) that are ~1 GB in size.
In all of my ...
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Create multiband raster from .las file using PDAL
I am quite new to creating rasters from point cloud (.las) files. Basically, I would like to use PDAL and its writers.gdal stage to write a raster with two bands.
The first band should be written ...
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Substracting water mask
I have a polygon with water bodies of my AOI. I would like to clip the water bodies from my NDVI raster layer ( like a water mask). I haven't found a tool in qgis or arcgis pro so far.
Do you have any ...
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Calculating the majority value pixel in a polygon and the percentage of this value within the polygon. QGIS
I have a big shapefile ( more than 500.000 polygons) and a raster file. I want to calculate the majority pixel per polygon, which I can do with zonal statistics. However, I also need the percentage of ...
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Convert QGIS heatmap raster output to vector
I am quite new to QGIS and I am trying to create a species distribution map using public reporting data. I can very easily generate a heatmap by first converting the pentad data to vector centroid ...
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Creating raster based on function of distance to points and assorted attributes in QGIS
In QGIS 3.30 I have a dataset of points associated with several values, call them integers A and B.
I want to create a raster with maybe 5km x 5km pixels where the value associated with each pixel ...
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Extracting rasters multi-value to points
I have a point shapefile and 90000 raster files with precipitation data. For each point, I tried extracting precipitation data from the rasters to points (gauge stations) using ArcGIS model builder, ...
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raster2pgsql excessive memory usage
I'm attempting to upload a raster to a PostgreSQL (PostGIS) database using raster2pgsql and I have noticed that it is using an excessive amount of RAM, over 25GB worth. The file I'm trying to upload ...
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ArcGIS Pro - Raster percentiles
In ArcGIS Pro I have a continuous raster.
I want to calculate an upper and lower percentile value and apply to smooth out the range of values. For example applying the 90th percentile value to the top ...
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Improve GeoServer WMTS service TIFF quality
How can I improve raster clarity in WMTS service in OpenLayers or QGIS? It seem that after I tile the raster, it downsample my origin data.
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Concatenate two rasters into a single raster with multiple bands GDAL
Maybe I am not asking the question with the appropriate English words, but I would like to basically concatenate multi bands rasters (two or more) into a single raster with all the bands intact. The ...
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Extracting points in a regular interval from TIN-Interpolation raster in QGIS
I had million of points with x, y and z. I could not filter them in QGIS in order to get them in an interval of every 0,9m. So what I did is TIN-Interpolation and I do have a raster now.
How can I get ...
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QGIS Report Slope Results
How could I report information about a raster result? In this case I have done slope analysis, and have reclassified it into 5 values for particular slopes. Now I am wondering if I can report ...
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Raster CRS projection inconsistency in QGIS
I have a number of satellite images covering Greece - downloaded from USGS: Earth Explorer "Landsat-Collection 2-Level1" collection.
The one group of images has a default CRS projection '...
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GeoServer's RasterZonalStatistics result interpretation
I am using GeoServer and the RasterZonalStatistics tool with a land use, single-band raster dataset. In the whole raster, each pixel represents a land use category and is given values between 1 and ...
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Retrieve raster cell values in qfield
Is there a way to retrieve raster cell values in qfield (Android version 2.7.6). Similar to the identify tool in qgis or arcgis?
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Raster turns black and white in ArcMap
So, I have been doing land use classification using SCP in QGIS and then I exported the raster as GeoTIFF file. I try to open this raster in ArcMap but it shows black and white and no classification ...
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Cut out parts of raster using polygons
I am looking to cut out some areas of a large raster using polygons.
The existing clipping tools only cut the raster to the size of the polygon, but I just want to cut the areas of the polygons out of ...
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How to use ArcSDE to extract raster value (equivalent to PostGIS ST_Value function)
Is it possible to use ArcSDE SQL functions to extract a raster value from a vector point in a database (Oracle/PostgreSQL/SQL Server) with ArcSDE, and if so then how?
I want to use SQL to do this, ...
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Error clipping raster by extent QGIS
While trying to clip raster using X,Y values this kind of error occurs:
GDAL command output:
ERROR 3: Free disk space available is 73209118720 bytes, whereas 1781328410624 are at least necessary. You ...
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Add vertical units to a DEM in ArcGIS Pro
I know that this may have been "answered" on other questions, but I am new to ArcGIS Pro, and they did not provide the guidance I need.
I am currently working on a project for a class, and I ...
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GDAL BuildVRT last image in list does not appear
The following code does not put the last file in the list on top, as it says in the description of the doc:
"If there is some amount of spatial overlapping between files, the order of files ...
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How to calculate the weighted average of a raster for the pixels touching a layer corresponding to a buffer (ArcGIS Pro)
I have a first raster layer which represents pixels of about 30m by 30m.My second layer corresponds to a circular buffer with a radius of 500m (I calculated the buffer from a point layer)
I have a ...
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Plotting CALIPSO data in R
I am trying to plot one subdataset of CALIPSO which is in hdf format using R. The data is totally new to me as it's LiDAR data. I am not able to understand how to plot a graph between backscatter ...
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Least cost path: what does least cost value represent, based on slope raster layer
Context and question
I have a raster layer with slopes in percent and used the least cost path plugin in QGIS to calculate the least cost path from start to end. I try now to understand what the ...
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Partial raster dataset substitution workflow with virtual raster
I have scripted a workflow in ArcGIS Pro where a set of rasters gets some new data for certain areas, which is updated by building a Mosaic Dataset where the new rasters are layed on top of the old ...
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Get the pixel value of a raster object using Python and ArcPy
I used the following code to get the pixel value of specific location of a DEM image (in GRID format):
import arcpy
from arcpy.sa import *
inRaster="C:\\data\\dem"
slop_temp=Slope(inRaster)
...
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Reducing resolution of raster layer in QGIS: "Save as..." or "Align Raster..."?
In QGIS (Version 3.22), if I need to change (reduce) the resolution of a raster layer, I can simply choose "Save as.." from the "Layer" menu or I can use the "Align Raster&...
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How to accurately isolate Europe from a rasterised world map image
There is a World Map of Autumnal UV provided for educational purposes by Nina Jablonski (created by George Chaplin) that I want to analyse.
In particular, I want to use Python to statistically analyse ...
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Derive a raster layer with distance to the nearest forest polygon in QGIS
I am preparing a set of environmental variables and I am fairly new to QGIS.
I am in possession of a land cover raster layer (downloaded from Copernicus) which I have reclassified for my study area ...
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VIIRIS Nightlights resolution when merging raster files in R
I do download Nightlights data from NASA (login neccessary, I`ve got the one for Germany tiles h18h19 v03 v04, four files in total) :
https://ladsweb.modaps.eosdis.nasa.gov/archive/allData/5000/...
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