To extract Normalised Difference Vegetation Index (NDVI), we mustconvert satellite images from digital number to reflectance form? In other words, it is possible to extract NDVI directly from satellite images which are in Digital Number (DN) mood?
Aldo Tapia Araya
Yes, from processing baseline 04.00, Sentinel-2 images are distributed with scale and offset (from https://sentinels.copernicus.eu/web/sentinel/technical-guides/sentinel-2-msi/processing-baseline):
L1C_TOAi = (L1C_DNi + RADIO_ADD_OFFSETi) / QUANTIFICATION_VALUEi
Offset is defined in metadata (check .XML file). In order to compute NDVI, you must convert to TOA first.
This applied to scenes from Jan 25, 2022.
1 votes
0 thanks
More Gholamreza Nikravesh's questions See All
Similar questions and discussions