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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QGIS 3.22.7 - Trouble converting vector to raster (ERROR 1: Wrong value for -ts parameter)
I am learning QGIS, and I have a series of polygons that I need to turn into a raster. The shapefile I am working with can be downloaded here (shapefile size is 3 KB). I am using the Rasterize tool, ...
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Doubt about attribute table in R terra package [closed]
I built a classification algorithm using rf and realized maps using predict function of the terra package.
The variable I used for classification had 3 different levels.
Following the indications on ...
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Change the resolution of the friction surface raster and compute cumulative travel time in R
I have downloaded the 2015 friction surface from the Malaria Atlas project website (see bottom of the page). On their websites, authors specify that the measure units of such a raster are minutes to ...
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Projecting rasters, shift to the north
I would like to project one raster onto another and while doing so I think the values are changing their position "to the north".
Is this an expected behavior?
I was hoping to create a ...
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QGIS 3.22.8 Raster sampling with polygons
This is a DEM of a slope. I have made a polygon grid 10X10. I can't find a command to sample the raster by polygons. I've thought something similar with r.neighbours picking the minimum value of the ...
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How to crop an ASCII file?
I have data downloaded from https://sedac.ciesin.columbia.edu/data/set/gpw-v4-population-count-rev11. It is in an ASCII file, and I want to plot the map and the populations of just California. What is ...
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Performing a k-means clustering with raster time series
I would like to perform a k-means clustering on time series data. I tried doing it with rts package.
library(rts)
path <- system.file("external", package="rts")
lst <- list....
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Mean of NDVI rasters across time point in QGIS after removing bad quality pixels
I have several NDVI and EVI rasters from different time points across a study period. These are of a region in Burkina Faso, and during the rainy season pixel reliability can be low. I have first ...
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How to create custom tool via Python that selects by attribute, then outputs new feature classes
I am trying to create a custom tool via python script that selects features in multiple fc's within a feature dataset that are missing values, then from the selected features, creates two outputs: one ...
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Get element in raster array based on BNG coordinates
I have some BNG coordinates which are converted from lat and long using proj4. I also have a raster file based on BNG. I want to get the relevant element from the raster array based on the coordinates ...
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r Terra Mosaic Raster uses huge amounts of memory and takes too long - any alternatives?
I built a process using google earth engine code editor to output a raster of urban land cover in Wisconsin. Google exports these as 210 shard which are geotiffs ranging from 2-100mb in size. Most are ...
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Unable to setup geoserver WMS layer as a background map in Qlik
When trying to add a WMS layer from geoserver in QLIK, despite being able to see the list of layers from different links, these layers don't show on the map.
For example, when trying to follow this ...
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Extract values from raster matching csv and raster filenames
I have a folder with many csv files. Each file has several columns as well as lat and long columns. Another folder have many rasters in tif format. The .csv files are named based on Julian date (e.g. ...
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How / is it possible to extract polygons from raster (ex: crop boundaries from satellite imagery)?
Is there any librairies/tools/others that can extract polygons out of crop boundaries from a satellite imagery. On the example below (random location in Belgium), the various fields limits are very ...
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Why referenced or derived mosaic datasets do not project rasters of different coordinate system correctly on-the-fly?
I am using ArcMap.
I have many mosaic datasets in a projected coordinate system and I would like to project them into another projected coordinate system (different datum), but without locating and ...
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Getting extent of raster in ArcMap to 12 decimal places
I have a raster file in arcmap and want to get the extent of the raster to 12 decimal places, the extent in properties gives 9 places.
Does anyone know how I can increase it?
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Looping to do cloud mask for several raster files in R [closed]
I have over 200 land surface temp (LST) rasters and I want to mask each LST raster using the corresponding cloud Mask raster. The working directory has two folders one for LST and one for cloud Mask. ...
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Saving PostGIS raster as netCDF from SQL Error
I am trying to save a raster table in PostGIS as a netCDF file. When doing so, I get the following error:
rt_raster_to_gdal: Output GDAL driver does not support CreateCopy and/or VirtualIO.
Reading ...
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R: Cannot create a RasterLayer object from this file
I need to download the climate data from CHELSA in form of GeoTIFF file. I need many layers, for which I downloaded them successfully but failed to load them as raster. For simplicity here is how to ...
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Using reclassify method from ArcPy to set range of slope map
I'm having a bit of trouble with the syntax and some of the parameters for some functions in ArcPy (I'm completely new to it and struggle with the documentation quite a bit). Specifically, I'm trying ...
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Subtracting area of a specific set of raster values from polygon area using QGIS
I am currently working with parcel data and a raster slope analysis in % change I created with DEM data. I symbolized the slope analysis discrete 0-2.5%, 2.5-5%, 5-7%, 7-12%, 12+% and overlayed it ...
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How to know what URL points to a specific tile when using a WMS?
I can view the tiles provided by a WMS service using QGIS. I add this: https://resource.sgu.se/service/wms/130/jorddjupsmodell URL as a WMS layer, I get this view:
(More info on URL source: here)
...
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Download ArcGIS Rest Server (Tile) to Shapefile
I was confused when I found that ArcGIS Rest Server was still in the Tile. In this case I want to download it as Geojson/Shapefile.
Is it possible?
Because when I try to connect it in QGIS it's still ...
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23
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DEM raster scale incorrect after running slope analysis QGIS
Working with DEM rasters from TNM 3DEP elevation data and trying to create a percentage slope map in QGIS. I added my rasters and tried running both the gdal slope that allows for % slope and the ...
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44
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Raster values changed after clipping with polygon [closed]
The procedure went well. Image 1 represents the raster (Chelsa) of annual mean temperature (bio1). I clipped it using a shapefile of country boundaries and the resulting image is image 2. As you can ...
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35
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QGIS histogram shows non-existent values
I work with Sentinel-2 images. I wanted to plot a histogram of a cloudmask, but it showed non-existent values.
I used the MSK_CLDPRB_20m.jp2 layer, which is a raster that shows the probability of ...
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How to calculate distance to the nearest river(s) given an elevation(s) in R [closed]
I have elevation points for my study sites and would like to calculate the distance to the nearest river for each site. I tried to download reduced river raster masks via this link (https://osmdata....
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How to export arguments for terra's app function when using multiple cores?
Suppose the following example:
library(terra)
r <- rast()
r1 <- setValues(r, rnorm(ncell(r)))
r2 <- setValues(r, rnorm(ncell(r)))
r3 <- setValues(r, rnorm(ncell(r)))
rs <- c(r1,r2,r3)
...
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Clipping a raster converted to a polygon with a polygon [closed]
I have a task to figure out how many agricultural areas are located in a defined altitude. The agricultural areas were a polygon, while the altitude/DMNV was a raster. I converted it to a polygon and ...
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30
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How many days have precipitation in attribute table from raster [duplicate]
I have a test CSV file that extracted by raster data in ArcGIS Pro with 24 points and 20 years daily data, which contains almost 7400 columns starts with D_20000601,.... and contains a value of ...
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Registering raster layers in Amazon RDS PostgreSQL using enable_out_db parameter
I have an AWS RDS PostgreSQL instance (v.11) that I'm currently storing vector data in. I also have a lot of raster layers in AWS S3 that are COG geotiffs. I'd like to register them in the database to ...
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2
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FME unwanted conversion of RGB to palette in PNG writer
I have a pile of TIFF images (aerial photography) that I want to convert to PNG. Band interpretation of my source TIFF files is allways RGB, cp. gdalinfo:
C:\OSGeo4W>gdalinfo -mm -stats s:\ER-GIS-...
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Plotting a buffer polygon over wrld_simpl
I want to create a buffer around a set of spatial points and plot it over wrld_simpl, without using ggplot2. Yet, there seem to be some issues with the projection I do not quite understand.
here is my ...
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How to get RGB values of clicked point on a WMS raster?
I connect to a WMS service: https://resource.sgu.se/service/wms/130/jorddjupsmodell
(More info on them: here).
I can successfully open and access pixel values:
After clicking on Identify Features (on ...
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1
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Changing band datatype to uint64 using rasterio
I have a raster, input.tif. It has 4 layers, and uint8 datatype, as shown in the metadata:
import rasterio
with rasterio.open('input.tif') as src:
print(src.meta)
Output:
{'driver': 'GTiff', '...
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True color (RGB) is not created with Landsat5(TM) images
The true color (RGB) is not created with the Landsat5 image.
I downloaded the TM video of Landsat5 from the USGS (earth explorer). I have videos from 1985 and 1986.
"...
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Different values when changing sources of the same raster dataset
I changed the original raster value using R (left in the figure).
But I got a different result.
Why occurs this?
All of the information is the same, just different sources.
> original_raster
class ...
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2
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77
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Calculate area for raster in R
I want to calculate area for each different class of landuse for raster image as shown below:-
The dimension of the raster image is as follows:
class : RasterLayer
dimensions : 16366, 29848, ...
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Using ArcMap attribute table
I am new to ArcMap.
I work with with the attribute table, so I took data from the Esri LULC site converting it from raster to polygon.
What I want to do is combine all of the same data into 7 features....
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What could go wrong using gdal_calc to sum pixel values of a multiband raster?
I have a raster, input.tif. I can open it using rasterio and read 3 bands:
import rasterio
with rasterio.open('input.tif') as src:
data1 = src.read(1)
data2 = src.read(2)
data3 = src.read(...
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Zonal Statistics Spatial Join Raster to Polygon in Python
I have a data frame that consists of 3 polygons
I have a raster with a single band
Seems like Zonal statistics as a table in ArcGIS does the job but I am using pure python script on this one; with no ...
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Interpolate specific areas of raster layer
I want to interpolate height (Z) values in a raster layer. The problem is that there is a body of water with no data in the middle of it and the overall area is not square; so also no data around.
Is ...
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Adding raster TIFF image directly on the map using OpenLayers without using GeoServer?
I want to know how to add an raster tif image onto map using OpenLayers
var imgextent = [extent array];
var geoRasterMap = new ol.layer.Image({
//...
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21
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Generate XYZ tiles (MBTiles)
I'm trying to generate an offline image via Googlemaps web layer using Genereate XYZ Tiles (MBTiles) and keep getting the following error (this has never happened before);
"Traceback (most recent ...
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Interactive Gridding tool in QGIS?
I'm looking to make a heatmap type raster based on point data in QGIS. I'm used to doing this in Mapinfo using the "Interactive Gridding" function in the Surfaces tab. Is there an equivalent ...
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Summing satellite cloud masks creates weird blocks along water
I'm trying to sum 150 Sentinel-2 cloud masks together.
Before I do this I have reclassify every pixel into a 1(cloud) or a 0(no cloud) based on the original value. This results in:
After that I sum ...
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1
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How to convert raster file into a series of SQL commands
I am trying to save raster data to the PostgreSQL database. I know that there exists raster2psql.exe, but this command limits me from adding additional columns to the table. For this reason, I would ...
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How can I configure zoom extent in Mapbox when generating raster tilesets from GeoTIFF?
GOAL
I'm using Mapbox to generate raster tilesets from raw GeoTIFFs. The GeoTIFFs have a resolution such that a single pixel represents roughly a 5km x 5km square on the map. I hope to generate and ...
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QGIS Raster Convert Negative Values to NULL
I have a DEM layer in QGIS and want to replace all cells with negative values to the value "NULL". How can I achieve this please?
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QGIS: Cross-tabulation table full of zero values
I want to calculate the Night Light Development Index (NLDI). For this reason I am using a night-time lights satellite image and a population raster layer, which they have the same dimensions, extent ...
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