Using satpy, Blending multiple satellite image

Question

I want blend multiple satellite images. but an error occured. I followed the example on the satpy document.

here is code and netcdf file is here : https://drive.google.com/drive/folders/1zp6EBVfjuh41LDRRZo4PJoeGGGn13AKy?usp=sharing

from glob import glob
from satpy import Scene, MultiScene, DataQuery
from satpy.utils import debug_on
debug_on()


areaid = 'worldeqc3km70'

eumetsat = glob('E:/Global/combine_test/MSG4-SEVI-MSG15-0100-NA-20210801000010.306000000Z-20210801001259-4774254.nat')
goes17 = glob('E:/Global/combine_test/OR_ABI-L1b-RadF-M6C13_G17_s20212130000319_e20212130009396_c20212130009445.nc')
gk2a = glob('E:/Global/combine_test/gk2a_ami_le1b_ir105_fd020ge_202108010000.nc')
goes17_scene = Scene(reader="abi_l1b", filenames=goes17)
eumetsat_scene =  Scene(reader="seviri_l1b_native", filenames=eumetsat)
gk2a_scene = Scene(reader="ami_l1b", filenames=gk2a)

goes17_scene.load(["C13"])
eumetsat_scene.load(['IR_108'])
gk2a_scene.load(["IR105"])

mscn = MultiScene([goes17_scene, eumetsat_scene, gk2a_scene])

#groups = {DataQuery(name='IR_group', wavelength=(9.8, 10.8, 11.8)): ['C13', 'IR105', 'IR_108']}
groups = {DataQuery(name="IR_group", wavelength=(10, 11, 12)): ['C13', 'IR_108', 'IR105']}

mscn.group(groups)
print(mscn.loaded_dataset_ids)



resampled = mscn.resample(areaid, reduce_data=False)
blended = resampled.blend()

blended.save_datasets(filename='./test_{area}.png'.format(area=areaid))

Error message: RuntimeError: None of the requested datasets have been generated or could not be loaded. Requested composite inputs may need to have matching dimensions (eg. through resampling).

Answer 1

As mentioned in the comments this is a known bug that will hopefully be fixed in the next couple weeks. Follow issue 2089 for more information.

The short-term workaround is to make your own "blend" method that handles things the way you expect:

from satpy.multiscene import stack

def my_blend(mscn, common_datasets, blend_function=stack):
    new_scn = Scene()
    for ds_id in common_datasets:
        datasets = [scn[ds_id] for scn in mscn.scenes if ds_id in scn]
        new_scn[ds_id] = blend_function(datasets)

    return new_scn

blended = my_blend(resampled, ["ir_group"])