Additional smoothing in FANO calculation to address blockiness in output ETf images (#83)

* Downscale to 90m and smooth with focal mean of radius 5 for smooth_Tc_layered in image.py...

This is supposed to take care of lack of smoothness from coarse Tcorr. Credit to Leo Laipelt!

* Update test_c_image.py

Updating test values to account for new FANO smoothing

* Downscale to 90m and smooth with focal mean of radius 5 for smooth_Tc_layered in image.py...

This is supposed to take care of lack of smoothness from coarse Tcorr. Credit to Leo Laipelt!

---------

Co-authored-by: gparrish <[email protected]>

Author: cgmorton

openet/ssebop/image.py

@@ -884,8 +884,10 @@ def tcold_FANO(self):
         ee.Image of Tcold values
 
         """
+        gridsize_smooth = 90
         gridsize_fine = 240
         gridsize_coarse = 4800
+        smooth_transform = [gridsize_smooth, 0, 15, 0, -gridsize_smooth, 15]
         fine_transform = [gridsize_fine, 0, 15, 0, -gridsize_fine, 15]
         self.coarse_transform = [gridsize_coarse, 0, 15, 0, -gridsize_coarse, 15]
         dt_coeff = 0.125
@@ -1003,15 +1005,15 @@ def tcold_FANO(self):
         self.hot_dry_tcorr = Tc_fine
 
         ## ---------- Smoothing the FANO for Ag together starting with mixed landscape -------
-
-        # 1 pixel of smoothing to the main Tc where we make use of landcovers
+        # downscaling to 90 and smoothing with a 5x5 Tc where we make use of landcovers
         self.smooth_Tc_Layered = (
             self.tc_layered
-            .focalMean(1, 'square', 'pixels')
-            .reproject(self.crs, fine_transform)
+            .reproject(self.crs, smooth_transform)
+            .focalMean(5, 'square', 'pixels')
             .rename('lst')
         )
 
+
         # Tcold with edge-cases handled.
         return (
             lst

openet/ssebop/tests/test_c_image.py

@@ -566,9 +566,11 @@ def test_Image_from_method_kwargs():
 @pytest.mark.parametrize(
     'tcold_src, image_id, xy, expected',
     [
-        # Old FANO Tcorr: 0.9785567103858176
-        ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 303.4515201604769],
-        ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 303.4515201604769],
+        ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 302.9531086729748],
+        ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 302.9531086729748],
+        # Old approach without smoothing
+        # ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 303.4515201604769],
+        # ['FANO', 'LANDSAT/LC08/C02/T1_L2/LC08_042035_20150713', SCENE_POINT, 303.4515201604769],
     ]
 )
 def test_Image_tcold_fano_source(tcold_src, image_id, xy, expected, tol=0.000001):

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "openet-ssebop"
-version = "0.7.0"
+version = "0.7.1"
 authors = [
     { name = "Gabe Parrish", email = "[email protected]" },
     { name = "Mac Friedrichs", email = "[email protected]" },