How to downsample a raster using the gdal max method using python?

Question

I want to downsample a raster image using the max method that is available in GDAL in python.

In other words I would like to recreate the following bash command in python code:

gdalwarp -tr 32 32 -r max input_image.tif resampled_image.tif

I have found the following solution but for some reason this changes the values in the image to a range between approximately 0 and 2 when I load the created tif file.

How can I resample a raster image in python using the max method?

Answer 1

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.run('gdalwarp -tr 32 32 -r max input_image.tif resampled_image.tif')