[GRASS-git] [OSGeo/grass-addons] 57b026: i.zero2null

[Markus Metz]

  Branch: refs/heads/i.zero2null
  Home:   https://github.com/OSGeo/grass-addons
  Commit: 57b026fb6780d17b9dc18023a91a42f842606bc3
      https://github.com/OSGeo/grass-addons/commit/57b026fb6780d17b9dc18023a91a42f842606bc3
  Author: Markus Metz <markus.metz.giswork at gmail.com>
  Date:   2020-06-13 (Sat, 13 Jun 2020)

  Changed paths:
    A grass7/imagery/i.zero2null/Makefile
    A grass7/imagery/i.zero2null/i.zero2null.html
    A grass7/imagery/i.zero2null/i.zero2null.py

  Log Message:
  -----------
  i.zero2null

fix nodata encoding for Sentinel-2 imagery, and possibly others
the value zero does not make sense for reflectance being the proportion of incoming light reflected back
zero is only possible for absolute black, all incoming light is completely absorbed (black holes can do that)