Enhanced Normalized Difference Vegetation Index
The traditional NDVI uses only red and near infrared data. ENDVI is a close equivalent and modified version of NDVI but since it is used with BGNIR data instead of RGNIR the calculation is done differently.
ENDVI uses Blue and Green visible light instead of the Red only method of the standard NDVI algorithm. This allows for better isolation of plant health indicators.
A normal healthy plant will reflect both visible Green and NIR light while absorbing Blue visible light. In the ENDVI measurement we are calculating the relationship between high absorption of this Blue light and high reflectance of Green and NIR waves as an indicator of plant health.
ENDVI= ((NIR+Green)-(2*Blue)) / ((NIR+Green)+(2*Blue))
With these normalized values you will see a range of -1 to 1 in the output ENDVI file.