I’m doing DOS corrections for the sentinel-2a data. From SNAP I export to ENVI. Then I did a DOS correction in ENVI. What I ask is, How do I change the data format from ENVI so that it can be processed back into SNAP? Anyone please help
I can*t exactly tell you the steps, but ENVI probably allows to save the data to GeoTiff or NetCDF. You can import these in SNAP. Aso the stored ENVI files can be read. But not all features are supported
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the ENVI raster format consists of an img and an hdr file.
File > Open > select the hdr file
should work to load the data back into SNAP.
This works the other way round as well, (img and hdr are inside the data folder of a BEAM DIMAP product).
Maybe these resources help you:
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Thank you for our help. Does sentinel-2a need dark subtraction to get TSS data?
This is surely beneficial. A real AC would be even better. Try sen2cor, for example.
Or try C2RCC for S2 MSI data. It is installed along with the S3TBX.
It does an AC over water and computes TSM too. And if I’m not wrong TSM is the same as TSS.
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Dark subtraction may not work well in areas of high TSS/TSM. Ideally, atmospheric correction would use optical characteristics of the suspended matter, so may need a regional/seasonal algorithm. Hydrolight is often used with in situ optical data for lakes and coastal waters: Spectral inversion algorithm: Sensor Independent Ocean Color prosessor (SIOCS). There is a need for better databases of TSM optical properties so people can share algorithms across regions with similar optical properties.
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