The VIBI operator algorithm computes the Vegetation Index Built-up Index from a given product.

The VIBI results from the following equation:

VIBI = ((N - R) / (N + R)) / (((N - R) / (N + R)) + ((S1 - N) / (S1 + N)))

, where:

The bands are:

- R is the Red band
- N is the NIR band
- S1 is the SWIR 1 band

Also the processor computes an additional flags band called 'vibi_flags' with the following bit coding:

Bit Position	Description
Bit 0	The computed value for VIBI is NAN or is Infinite
Bit 1	The computed value for VIBI is less than -1 (minus one)
Bit 2	The computed value for VIBI is greater than 1 (one)