I want to resample rasters of e.g. 2 m resolution to the same raster cell size and projection of an existing raster (25 m). However I cannot really find answers how to do it properly. I managed to resample the input raster to 25 m, but this means the new raster grid has its own grid projection/orientation, thus not matching the 25 m raster grid of the masking raster.
Following comment by @RJJoling, this is QGIS Align Rasters tool workflow:
- Click on a green + icon.
Input raster layeris the raster you want to change (in your case: originally 2m resolution). Give an
Output raster filename. Various
Resampling methodare available... , Bilinear or Cubic would be good enough to upscale (coarsen) the grid size.
Raster layers to align: lists the raster you want to change (from 1.)
Reference layeris the base layer. In your case the existing 25m resolution raster.
Clip to extent optionis also important in many cases (especially when you need to perform raster-raster calculations).
You can use the GDAL Tools plug-in. After turning on the plug-in in the Raster menu you can find Conversion/Translate. It is a front-end for gdal_translate which can change resolution too. You can set outsize in percents, you should set 1250% for the outsize.
Alternatively the gdal_translate command line version can be used, where the output resolution can be set using -tr switch.
Another alternative can be found in the processing toolbox (e.g. in SAGA or GRASS group)