w_scan2 is a small channel scan tool which generates ATSC, DVB-C,
DVB-S/S2 and DVB-T/T2 channels.conf files.

It's based on the old "scan" tool from linuxtv-dvb-apps-1.1.0. The
differences are:
* no initial tuning data needed, because scanning without this data
  is exactly what a scan tool like this should do.
* it detects automatically which DVB/ATSC card to use.
* much more output formats, interfacing to other dtv software.

w_scan2 is a fork of the original w_scan from
https://www.gen2vdr.de/wirbel/w_scan/index2.html

Main changes from w_scan to w_scan2:
* keep duplicate transponders by default because a stronger transponder
  with the same ID might have a higher frequency and be discarded simply
  because it's scanned later. Also don't replace the current transponder
  with an advertised one by default. The latter may have a lower signal
  strength. More details here:
  https://stefantalpalaru.wordpress.com/2016/02/04/scan-all-the-things/
  The old behaviour can be enabled with -d (--delete-duplicate-transponders).
* re-enable VHF band III in Europe