The BIXS operator algorithm computes the SPOT HRV XS-based Brightness Index from a given product.

The BIXS results from the following equation:

BIXS = pow(((pow(G , 2.0) + pow(R , 2.0)) / 2.0) , 0.5)

, where:

The bands are:

- G is the Green band
- R is the Red band

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

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