Questions tagged [resampling]

To alter the frequency of sampled data points in continuous data.

Filter by
Sorted by
Tagged with
0 votes
0 answers
11 views

ENVI 5.6.2 HSV problem

I've used ENVI a lot in the past, but am a bit rusty. I have never ran into this problem and can't find anything online about it. I'm trying to do HSV sharpening with 3 band multispectral data and a ...
R. Ian Cunningham's user avatar
0 votes
0 answers
33 views

How do I resample a raster layer over another layer in QGIS 3.x?

I have 2 raster layers (the full same area): Layer 1: 30 m resolution, coordinate system is EPSG:32643, layer size is 7406x6801; Layer 2: 10 m resolution, coordinate system is WGS 84, layer size is ...
senek's user avatar
  • 65
0 votes
0 answers
81 views

Resample Sentinel-2 bands from 20m to 10m using GEE code outside of GEE

I want to resample the 20 meters bands of Sentinel-2 to 10 meters. I found this piece of code in GEE and after trying it out, this is what I would like to do to my Sentinel images but outside of GEE. ...
rrwork___'s user avatar
3 votes
1 answer
160 views

Generating DEM that gives realistic contour

I am quite new QGIS user. I have point data from the field and I generated DEM and contour. However, the contours are a bit unrealistic. I have attached the image. The green contour is the contour ...
Usha's user avatar
  • 137
0 votes
0 answers
61 views

Problems with the SAGA Next Gen Tool "Resampling Filter"

When running the Saga Next Gen tool "Resampling-Filter" I get the error message: failed: could not find a suitable import driver**" and "**[Import Raster] Execution failed (less ...
Adrian's user avatar
  • 1
0 votes
1 answer
86 views

QGIS - keep square pixels in resampling

I have a raster file (asc) with a resolution of about 10m, square pixels and an extent of X: 15929 Y: 16159. I am trying to resample this to a larger resolution (tried 20 and 30m). However, the output ...
etna_2605's user avatar
2 votes
1 answer
83 views

QGIS simple downsample of a raster

I'd like to downsample a DEM raster from 2m per pixel to 8m. I've tried using SAGA Multilevel B-spline interpolation (from raster) as suggested here, but though that results in an 8m resolution it ...
flyhigher's user avatar
  • 143
0 votes
0 answers
38 views

How to assign a value to a set of 25 identical pixels in a raster layer?

I am using ArcGIS Pro 3.1 I would like to create a new raster layer from an existing raster composed of 4 possible discrete values (MIN=0, MAX=4, VAL=0,1,2,3,4). This existing raster illustrate ...
Raphael's user avatar
0 votes
1 answer
51 views

R: Resample raster layer according to a polygon grid

I have a reference polygon grid and several raster layers with varying resolutions. I need to resample raster payers so that the cell sizes and locations of the new rasters match the cell sizes and ...
olu's user avatar
  • 3
0 votes
0 answers
152 views

Optimize the resampling and projection of multiple NetCDF files in R using terra

I have a set of 35 NetCDF files (continental scale), each containing 365 daily layers of climate data with a resolution of 5 km, s. I need to do two main tasks: Subset, s_sub, these files based on a ...
Sarash's user avatar
  • 45
1 vote
1 answer
46 views

QGIS Raster resampling without label changes

I am working on raster data that which is in a 5x5 meter resolution. I need to resample this to a 25x25 meter resolution. I have used resample.stats which works, but changes the label numbers into one ...
Hartje's user avatar
  • 133
0 votes
0 answers
88 views

Resampling Sentinel-2 images

I want to change Band-11 (SWIR Bands) of Sentinel-2 to 10m resolution. I found resampling process used for it. Doesn't it affect the spectral characteristics for processing further???
Walker's user avatar
  • 191
0 votes
0 answers
95 views

In GEE: Calculating area in WGS84 masking out regions with layers in different resolutions

I am trying to calculate the number of affected people by flooding, but only those who are living in urban areas. So essentially, I take the WorldPop dataset and overlay it with flood extent and land ...
vince's user avatar
  • 21
0 votes
0 answers
147 views

Image (Error) Image.reduceResolution: The input to reduceResolution does not have a valid default projection. Use setDefaultProjection() first

I would like to aggregate the 30m images to 990m on average through reduceResolution, but he shows me to add the default coordinate system, but I have already added it and this still happens. Below is ...
kunsheng liu's user avatar
3 votes
0 answers
457 views

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 ...
Eden's user avatar
  • 131
5 votes
1 answer
539 views

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 ...
Babel's user avatar
  • 70.4k
2 votes
1 answer
72 views

How to avoid gdalwarp converting to alpha band

I am running the following code in order to resample a single-band TIFF file, whose data are going from 0 to 100 with 255 being the nodata value "gdalwarp -t_srs "+srs+" -tr "+pxsz+...
Andrea's user avatar
  • 69
3 votes
1 answer
435 views

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&...
winnewoerp's user avatar
  • 1,508
0 votes
0 answers
14 views

Trying to resample data and the columns are off by 1

I am trying to run a MaxEnt model with layers from ArcGIS. I am new to MaxEnt modeling but from what I have learned everything must be exactly the same in all layers. Columns, rows, cell size, ...
JohnC3na's user avatar
0 votes
1 answer
269 views

Mosaicking cloud removed Sentinel2 imagery using Google Earth Engine [closed]

After struggling the cloud removing part of GEE, I have some questions regarding the mosaicking the result instead of using median(). What I learn about the difference between mosaic and median()/max()...
Cinnamon roll's user avatar
1 vote
1 answer
293 views

Projection is not a function

I'm new to Google Earth Engine, just get started to learn how to load and process the Sentinel imagery on GEE. Today I wanted to resample the imagery downloaded from Sentinel2 into 10m (band 5 and ...
Cinnamon roll's user avatar
1 vote
1 answer
167 views

Reproject and resample raster1 to CRS and grid of raster2, but keeping the shape of the original raster

I am working with two raster files. path_target: shape (27502, 6133); CRS: EPSG 31255 wk_path: shape (294825, 570431); CRS: EPSG 31287 I would like to reproject path_target to EPSG 31287 and align the ...
KevinKo's user avatar
  • 21
0 votes
1 answer
83 views

Avoid adding a bunch of new features for one static location for repeat sampling efforts in Field Maps

I have built several maps and forms for their use in Field Maps for various projects. Most have been creating new features and filling out the form for the new location where we sampled. However, we ...
Ken's user avatar
  • 1
1 vote
1 answer
273 views

What's the difference between bicubic interpolation and cubic convolution?

Our remote sensing professor recently introduced us to bicubic interpolation and cubic convolution, implying that they're basically the same. Now that I'm studying for the exam, I wonder: Is that ...
Pixelcode's user avatar
  • 113
1 vote
1 answer
133 views

Miminum values of a raster change when applying r.resample

I am trying to aggregate a raster of a bioclimatic variable (can be downloaded here: https://envicloud.wsl.ch/#/?prefix=chelsa%2Fchelsa_V2%2FGLOBAL%2F > Climatologies > 1981-2010 > bio/ > ...
LT17's user avatar
  • 303
0 votes
0 answers
57 views

Downsample large raster without reprojecting first

How can I downsample a large TIFF (raster) which is projected in decimal degrees without first having to reproject it to meters. I know that in meters the resolution is 3cm and I want to downsample to ...
N_LLC's user avatar
  • 615
1 vote
2 answers
538 views

How to merge GeoTIFF files of different resolutions and utilize the higher resolution tile data where available

I've got a single 1/3 arc-sec GeoTIFF file covering an area and a handful of smaller, higher resolution 1 meter GeoTIFF files that cover only some of the area that the 1/3 arc-sec file covers. I'd ...
Matt R's user avatar
  • 45
1 vote
0 answers
95 views

Converting raster layer from EPSG:3003 to EPSG:4326

I am working with two type of raster layers: The first one is a .tif file downloaded from Worlclim database that is in WGS84 (EPSG:4326) coordinates reference system. So that, the resolution is ...
Floreanita's user avatar
2 votes
0 answers
146 views

Calculation of downscale factor for downsampling image using Rasterio

I have image with resolution of 30cm in WGS84 EPSG 4326. I want to down-scale the image to get the same image but with 50cm size of pixel. I have used Rasterio documentation (pages 80-81) in order to ...
ReutKeller's user avatar
  • 2,107
2 votes
0 answers
110 views

Resampling Sentinel-1 GRD data - should it be converted to linear scale before resampling?

I am trying to resample Sentinel - 1 data(original resolution of 10m) to 500m in GEE platform. #Resampling the image to 500m def resamp(image): resampd = image.reduceResolution( ...
CP Rajendiran's user avatar
1 vote
2 answers
450 views

SRTM raster looks pixelated with hillshade style in QGIS when zooming in

I have a project and I want to create a map using SRTM as a background. I upload it ... and it looks like that: But my project area is smaller, so I need to zoom it ... and when I do that, my SRTM ...
Cipanul's user avatar
  • 19
1 vote
1 answer
398 views

terra R package resample of non-empty raster by 'sum' produces empty raster

I have a raster x which is at a resolution of 100m and pixel value is its area in sqkm is suitable for an action, see below class : SpatRaster dimensions : 769, 716, 1 (nrow, ncol, nlyr) ...
tg110's user avatar
  • 810
0 votes
1 answer
324 views

Resampling using pyresample grid definition

I would like to resample a dataset to another projection and scale. Following the documentation in pyresample website here. We need to have an Area Definition, which is tedious to do. import numpy as ...
Faisal Al Nasser's user avatar
3 votes
3 answers
1k views

QGIS: Resample (upscale) raster using a Gaussian filter

I want to resample a raster from 15m to 460m using a Gaussian filter. The goal I am having a coarse image which I want to downscale. I also have a fine resolution band to assist the downscaling. The ...
Nikos's user avatar
  • 968
3 votes
2 answers
311 views

QGIS - Converting Vector to Raster and back to vector to resample resolution of vector data

I would like to convert my polygon data into a raster file to change the pixel resolution and then would like to convert it back to polygon data since this will allow it to be resampled to another ...
AhmedTech's user avatar
1 vote
1 answer
2k views

How to deal with Nan value when using rioxarray rio.reproject()?

I was trying to use rio.reproject_match() to match the resolution of two xarray datasets. However, when I used resample methods like Resampling.bilinear or Resampling.average, a large area would ...
QRW's user avatar
  • 43
0 votes
2 answers
110 views

stratifiedSample() gives an empty feature collection in Google Earth Engine

I am trying to sample 10 random points from each value in the 'QA60' band of a Sentinel-2 image for machine learning purposes. When I use the .stratifiedSample() function, I obtain an empty feature ...
Charbel El Khoury's user avatar
4 votes
1 answer
2k views

Specifying target resolution when resampling with rasterio

In GDAL warp you can simply set an xRes and yRes value. I'm trying to only use rasterio, but the process seems a lot less clear. According to the docs https://rasterio.readthedocs.io/en/latest/topics/...
hmnoidk's user avatar
  • 689
1 vote
0 answers
141 views

How can I group Land Cover Classification into urban vs rural areas and summarize Land Surface Temperature for each class in python? [closed]

I have NLCD land cover classifications from an .img file as follow: I would like to somehow reclassify these into Urban or Rural by taking all developed as urban and the rest, minus water as rural. ...
codee's user avatar
  • 11
2 votes
1 answer
178 views

Zonal Statistics as table on population raster does not produce correct regional population figures using ArcGIS Pro

I have a population raster (from Worldpop.org) with data on the population count of Philippines. It is unconstrained data from 2020, 100m resolution. Link to raster: https://www.worldpop.org/geodata/...
Madhumitha Ayyappan's user avatar
0 votes
1 answer
114 views

How does majority resampling technique works in ArcGIS?

I would like to understand how does the majority resampling technique works. To be specific the documentation below states that the method will use a 4X4 filter and will populate the output with the ...
Yogesh Chavan's user avatar
1 vote
1 answer
474 views

Resampling high resolution data into lower resolution based on most common value

I want to use a high-resolution classification (3cm) as training data for a classification using Sentinel 2 data (10m). To do so, I want find which high-res value is most common within each Sentinel &...
stijnionio's user avatar
1 vote
0 answers
396 views

Google Earth Engine: Output too large when reducing resolution and exporting to Google Cloud

I'm calculating a bareground layer for Africa using Sentinel-2 at 10m resolution. I want to reduce the resolution to 1000m and then export it to Google Cloud Storage. However, this gives me an error ...
mvdl's user avatar
  • 105
3 votes
1 answer
619 views

Resample raster but keep sum of total cell values the same

I am trying to resample a raster to a finer resolution, matching the resolution of my raster of interest. The problem is, my raster I'm resampling is a population raster. When I resample, the total ...
johnnyg's user avatar
  • 33
0 votes
2 answers
437 views

What's correct order of resampling, reprojecting and composing ImageCollection in GEE?

I want to resample, reproject and compose an image collection in python using the GEE API. My script now is this adm0 = ee.FeatureCollection("FAO/GAUL/2015/level0"); filter = ee.Filter....
justin fiedler's user avatar
1 vote
0 answers
102 views

Anti-alias raster layer by upscaling/ resampling

Recently, I performed a VGA analysis using Depthmap X. I moved the date over using a Mapinfo file (vector) and rasterised the values to the associated pixelsize. The analysis was conducted at a 2m ...
Topow's user avatar
  • 361
1 vote
0 answers
125 views

Should you resample rasters before or after raster calculator operations?

I struggle to understand if rasters should be resampled before or after doing some arithmetic. For example: Suppose I have a DTM and DSM of an AOI which were produced from the same instrument, but the ...
hmnoidk's user avatar
  • 689
1 vote
0 answers
285 views

Resampling high resolution binary raster

I have a large, high resolution raster of binary data that I need to reproject and resample to align with a lower resolution dataset. Because the original data is binary, I need to aggregate using the ...
Jaken's user avatar
  • 93
0 votes
1 answer
2k views

Resampling a raster with R

I'm trying to use the R function resample between two non matching Raster objects. The raster to resample has the following description hydrogate class : RasterLayer dimensions : 1163, 1499, ...
a.fornasiero's user avatar
0 votes
1 answer
478 views

Resolution of Python GDAL-generated GeoTiff different from plotted image

The Situation I use the GDAL library to warp geotiffs (subsequently referred to as "rasters") of different resolutions (30m and 500m) to a 100m (subsequently referred to as "default&...
Thierry's user avatar
  • 119

1
2 3 4 5 6