Why GeoWombat?#
GeoWombat uses xarray and rasterio to open geospatial rasters as chunked dask arrays. So, why not just use
these libraries directly?
GeoWombat is built on top of these libraries, with some key additions for added flexibility with raster I/O and data processing. Examples include:
On-the-fly CRS transformation
Automatic data alignment
Multi-image mosaicking
Flexible data writing over parallel tasks
Why not Rasterio?#
Rasterio is the engine behind much of the data transformations and I/O. However, rasterio loads data in memory as numpy arrays. We
wanted to build a library that could process rasters of any size.
Why not Xarray?#
Xarray’s open_rasterio function is the interface
to rasterio. It opens a delayed raster as a dask.array.Array,
which means data are not loaded into memory until requested. However, xarray is intended to be a
general purpose library. Therefore,
it does not include geo-specific tasks included in geowombat, such as radiometric adjustments, vector/raster interaction,
and special purpose I/O such as on-the-fly mosaicking.