avconv -y -i poc /dev/null avconv version 12.3, Copyright (c) 2000-2018 the Libav developers built on Mar 26 2018 12:39 with gcc 7 (SUSE Linux) [mov,mp4,m4a,3gp,3g2,mj2 @ 0x55f3b86b5320] moov atom not found
http://bugzilla.suse.com/show_bug.cgi?id=1143244
http://bugzilla.suse.com/show_bug.cgi?id=1143244#c1
Antonio Larrosa