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Just to add to what @Kostas VI. mentioned: Measuring means always approximation. If the approximation is "good enough", you would consider it "reliable data". What that exactely means has to be decided in each individual context. As general rule: if the data has higher resolution than the minimal size you need for your task, it's probably ...

4

I think it depends on what you want to do with it and what the image depicts. For example, a satellite image depicting Ocean Color (e.g. Sentinel-3 OLCI product) or Sea Surface Temperature (SLSTR product) can be considered continues, since the variables they depict are inherently continuous variables. However, if you wanted to discriminate between some ...

3

I realized the 'Extent' was not exactly the same among my raster layers. I set the same Layer to give the exact coordinates for Extent and now they are aligned.

3

Why not use the function defined in Mike T's answer from the post you linked to? def redistribute_vertices(geom, distance): if geom.geom_type == 'LineString': num_vert = int(round(geom.length / distance)) if num_vert == 0: num_vert = 1 return LineString( [geom.interpolate(float(n) / num_vert, normalized=...

2

You can use gdalwarp to achieve this. from osgeo import gdal # open reference file and get resolution referenceFile = "Path to reference file" reference = gdal.Open(referenceFile, 0) # this opens the file in only reading mode referenceTrans = reference.GetGeoTransform() x_res = referenceTrans[1] y_res = -referenceTrans[5] # make sure this value is ...

2

According to the resampling docs on the Earth Engine Guides, you can reduce resolution using the ee.Image.reproject() function. Check out the link for more on what's going on under the hood, and make note of the warnings they list there. var myCounty = ee.FeatureCollection('TIGER/2016/Counties') .filter(ee.Filter.eq('NAME', 'Kalawao')); var table = ...

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Try to specify the scale when reprojecting. var precipref_proj = precipref.reproject(dmProjection, null, 30).reduceResolution(...)

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The Define Projection tool is used when assigning/defining a coordinate reference system (CRS) to a dataset that doesn't have one defined at all (or changing an incorrectly defined CRS). It doesn't change the underlying coordinates. The Project Raster tool is used to transform a raster from one CRS to another. It does change the underlying coordinates. ...

1

It could be done with r.neighbors in grass : Sum number of cells using a 3x3 Count number of cells without Nan/Null value using a 3x3 Divide first generated raster by second one Example : Set a random region 3x3 cells g.region rows=3 cols=3 Initialize with random cell raster r.random.cells output=random_cells distance=0 ncells=5 Sum cells (3x3 is ...

1

I'm posting this as an "answer" because I don't know how to put screenshots in a comment - but I hope this helps you. I wonder if you have an older QGIS version where the resampling option isn't working correctly? Anyway, at 3.14.16 the Layer Styling > Resampling setting works for me, as shown below. The first image is a .tif drag-dropped into ...

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The problem was with alpha band, which was not warped correctly. We need to prevent the alpha band of the source image to be considered as such with -nosrcalpha parameter. Then it will be warped as regular band. Following command yields nice smooth image: gdalwarp \ -of GTiff -overwrite -r lanczos -nosrcalpha \ -tr 1.194328566968441 1.194328566968441 -...

1

I tried to generate points inside my various polygon boundaries of the shapefile by using below code: import ogr import random from osgeo import ogr from shapely.geometry import Point from shapely.prepared import prep from shapely.wkb import loads g = ogr.Open(inputShapeFile)# Open the shapefile for layer in g.GetLayer(0): field = loads(layer....

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The images you linked to are both 10m res, but I resampled one to 20m to demonstrate: gdal_translate -tr 20 20 should_be_20m_but_is_actually_10m.tif 20m.tif You need to resample the window as well: import numpy import rasterio from rasterio.enums import Resampling from rasterio.windows import Window resample_factor = 1/2 # Downsample to 1/2 of the ...

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Since it is continuous data you should either use bilinear interpolation or cubic convolution. The advantages and disadvantages of each can be found here. https://desktop.arcgis.com/en/arcmap/10.3/tools/environments/resampling-method.htm

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Normally when rendering an image, EE works at different scales for different zoom levels. The docs explain how this works. When you reproject, you force EE to work at the scale you specified, and depending on your zoom level, each map tile will contain more or less pixels. When zoomed out too far, each tile simply contain too many pixels for EE to handle . ...

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You are probably passing other resampling algorithm than max when using the solution you linked. The code should look like: from osgeo import gdal gdal.Warp('resampled_image.tif', 'input_image.tif', xRes=32 yRes=32, resampleAlg=gdal.GRA_Max) Another alternative is calling the command from Python using the subprocess module: import subprocess subprocess....

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Based on this quote from Javier GorroĆ±o; Andrew Banks; Ferran Gascon; Nigel P. Fox; Craig I. Underwood Novel techniques for the analysis of the TOA radiometric uncertainty Proc. SPIE 10000, Sensors, Systems, and Next-Generation Satellites XX, 100001H (19 October 2016): The last method are the B-splines interpolation that is implemented as the nominal ...

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When re-gridding to a coarser raster, always use an aggregation method, such as 'average' for continuous variables or 'mode' for categorical variables. Other appropriate aggregate methods for continuous variables include min, Q1, median, Q3 and max. Interpolation algorithms including 'bilinear' (among others) should only be used when re-gridding to a finer ...

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