I'm a beginner in satellite optical imagery.
I have a landsat 8 image (11 bands downloaded from http://earthexplorer.usgs.gov/) for which I need to calculate the NDVI (Normalized Difference Vegetation Index) and possibly the NDWI (normalized difference water index) as well.
Is it required to get the reflectance from the DN (calibration) before calculating the NDVI?
If so, what's the open-source software usually used for the purpose of this calibration?
أكثر...
I have a landsat 8 image (11 bands downloaded from http://earthexplorer.usgs.gov/) for which I need to calculate the NDVI (Normalized Difference Vegetation Index) and possibly the NDWI (normalized difference water index) as well.
Is it required to get the reflectance from the DN (calibration) before calculating the NDVI?
If so, what's the open-source software usually used for the purpose of this calibration?
أكثر...