Reproject raster

Draft: written, not yet checked by a person Operation · reproject-raster

Resamples a raster from its coordinate reference system into another.

Pitfall. Categorical rasters (land cover, classes) must use nearest or mode; other methods invent class values.

About this operation
Also called	Project Raster, Warp, Warp (reproject), gdalwarp
Group	`raster/crs`
Checks	`crs.reprojected, raster.resampling, raster.nodata`
Pitfalls	1 listed above
Columbus tool	`raster_op · reproject`
Notes	Not stated
Status	active
Broader	Not stated
Narrower	Not stated
Related	`reproject`

Parameters

Name	Type	Required	Default	Values	Note
`crs`	crs	yes	Not stated	Not stated	Not stated
`resampling`	enum	no	Not stated	`nearest, bilinear, cubic, average, mode`	Not stated
`resolution`	number	no	Not stated	Not stated	Output cell size in the target CRS units.

Inputs and outputs

Direction	Name	Type	Geometry	Note
Input	`raster`	raster	Not stated	Not stated
Output	`output`	raster	Not stated	Not stated

In each engine

Engine	Tool	Parameters	Differences
`gdal`	`gdal raster reproject`	`crs` → `output-crs` `resampling` → `resampling` `resolution` → `resolution` `raster` → `input` `output` → `output`	None noted
`postgis-raster`	`st_transform`	`crs` → `srid` : An SRID integer from spatial_ref_sys. `resampling` → `algorithm` : nearest = NearestNeighbour; bilinear = Bilinear; cubic = Cubic `resolution` → `scalexy` `raster` → `rast`	None noted
`qgis`	`gdal:warpreproject`	`crs` → `TARGET_CRS` `resampling` → `RESAMPLING` : nearest = 0; bilinear = 1; cubic = 2; average = 5; mode = 6 `resolution` → `TARGET_RESOLUTION` `raster` → `INPUT` `output` → `OUTPUT`	None noted
`rasterio`	`rasterio.warp.reproject`	`crs` → `dst_crs` `resampling` → `resampling` : nearest = 0; bilinear = 1; cubic = 2; average = 5; mode = 6. A rasterio.enums.Resampling member; the numbers are its values. `resolution` → `dst_resolution` `raster` → `source` `output` → `destination`	Works on arrays; the caller passes the source transform and CRS (src_transform, src_crs) and writes the result.
`rioxarray`	`rioxarray.raster_array.RasterArray.reproject`	`crs` → `dst_crs` `resampling` → `resampling` : nearest = 0; bilinear = 1; cubic = 2; average = 5; mode = 6. A rasterio.enums.Resampling member; the numbers are its values. `resolution` → `resolution`	Called through the .rio accessor of a DataArray (da.rio.reproject).
`terra`	`terra::project`	`crs` → `y` `resampling` → `method` : nearest = near; bilinear = bilinear; cubic = cubic; average = average; mode = mode `resolution` → `res` `raster` → `x`	The same function reprojects SpatVectors (vector reproject); y can also be a raster to match its grid.