The open_geotiff accessor method...

[brendancol]

For folks that don't know, xarray-spatial provides a GDAL-free open_geotiff function:

from xrspatial import open_geotiff

# scenario 1: directly use open_geotiff to create an xarray.DataArray
my_study_area_elevation = open_geotiff("elevation.tif")

xarray-spatial also provides an xr.DataArray / xr.Dataset accessor method .xrs which exposes the open_geotiff function ON an xarray.DataArray or xarray.Dataset object that can then serve as a template for loading additional data:

Simple example:

from xrspatial import open_geotiff

my_study_area_elevation = open_geotiff("elevation.tif")

# scenario 2: use open_geotiff through **accessor** method
my_landcover_data = my_study_area_elevation.xrs.open_geotiff("landcover.tif", unpack=True)  # equivalant to `mask_and_scale=True`
my_landcover_data = my_study_area_elevation.xrs.open_geotiff("landcover.tif", auto_reproject=True) # infers resampling param based on data but can be overridden
my_landcover_data = my_study_area_elevation.xrs.open_geotiff("landcover.tif", coregister=True) # tranform to match CRS, bounds, and shape of caller

A few things to note here:

• unpack parameter is analogous to mask_and_scale, and named because it aligns with the inverse operation, which is called pack which is easier to say than unmask_and_unscale.
• Then there is also, because we have metadata on the caller object, the data array or the data set, there is a parameter called auto_reproject, which will auto reproject the data into the, to match the caller's CRS.
• coregister indicates to return the output with matching shape, bounds, chunks and CRS of the caller object.

The vision here is that scaling, masking, reprojecting, and resampling are common enough tasks that it will be valuable to users to focus on making those steps easy from the beginning to speed up time to "analysis ready" arrays.

There are some difficult edge cases:

• I added in a warning in the scenario for:

huge_dask_array.xrs.open_geotiff("tiny.tif", coregister=True)

• datum transformation are not handled...

Would love to hear what people think.