The NHFD operator algorithm computes the Non-Homogeneous Feature Difference from a given product.

The NHFD results from the following equation:

NHFD = (RE1 - A) / (RE1 + A)

, where:

The bands are:

- A is the Aerosols band
- RE1 is the Red Edge 1 band
- R is the Red band

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

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