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by armin.mehrabian » Wed Feb 26, 2020 11:38 am America/New_York
Hi All,
I'm working on a process that requires, 1. L2 processing Sentinel2 and Landsat8 scenes through l2gen 2. Post-processing the Rrs outputs from step 1 outside seadas 3. create geolocated geotiffs from step 2 results
In order to create geolocated geotiffs in step 3 I use python Rasterio package. For that Rasterio takes the 4 boundary values (eastmost_lon, northmost_lat, ...). Now, the issue is that some of the scenes processed in step 1 through l2gen in the output have invalid boundary coordinates under /Metadata/Global_Attributes like
However, Metadata/Scan_Line_Attributes seems to have array valid scan line coordinates under slat, elat, slon, elon, clat, clon. If you pick the 4 extreme coordinates from here they do not form a rectangular bounding box. As a side note when I load the l2gen processed output in QGIS, the Extend values, which seems to correspond to the 4 bounding coordinates does not agree with any of the Metadata/Scan_Line_Attributes coordinates.
I'd love to know if anyone has suggestion on how can I correctly create geolocated geotiffs from output of step 2.
can you give me an L1 file where l2gen produces a coordinate box for the whole earth. Remember, if the scene is near a pole this bounding box is correct.
Yes, it looks like our L1 reader for MSI data is flagging any pixel with bad Lt as NAVFAIL. The scene you sent has mostly bad Lt except in the lower corner, which caused problems for the code which sets the North, South, East, West metadata. We have new software that can handle this situation and are working to get this into l2gen.
l1info uses the new stuff and can get you the correct limits:
INFO: FIRST SCAN LINE Start_Date=2018-01-24T14:47:14.456Z
INFO: LAST SCAN LINE End_Date=2018-01-24T14:47:31.646Z Lower_Left_Lon=-68.254745 Lower_Left_Lat=-16.367836 Lower_Right_Lon=-67.972183 Lower_Right_Lat=-16.366648