advpng(1) on Linux
The text be83ee7ea5a0, as Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
AdvanceCOMP PNG Compression Utility
Flags it lists
-
--force -
--iter -
--list -
--recompress -
--shrink-extra -
--shrink-fast -
--shrink-insane -
--shrink-normal -
--shrink-store -
-0 -
-1 -
-2 -
-3 -
-4 -
-f -
-i -
-l -
-z