avbin was downloaded from http://code.google.com/p/avbin/downloads/list 

Copyright (c) 2007 Alex Holkner

From avbin/README:

 | Due to the linkage between AVbin and FFmpeg, AVbin must be licensed under the
 | LGPL or GPL.  Currently all GPL features of the FFmpeg configuration are
 | disabled, permitting LGPL use.

Thus, the code is licensed under the GNU LGPL:

 | This library is free software; you can redistribute it and/or
 | modify it under the terms of the GNU Lesser General Public License as
 | published by the Free Software Foundation; either version 2.1 of
 | the License, or (at your option) any later version.
 |
 | This library is distributed in the hope that it will be useful,
 | but WITHOUT ANY WARRANTY; without even the implied warranty of
 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | Lesser General Public License for more details.
 |
 | You should have received a copy of the GNU General Public License
 | along with this program; if not, write to the Free Software
 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA

The Debian packaging is Copyright (c) 2009 Andrew Straw and Matthew Johnson
and is also distributed under the terms of the GNU LGPL.

On Debian GNU/Linux systems, the complete text of the GNU General Public
License can be found in `/usr/share/common-licenses/GPL' and the text of the
GNU Lesser General Public License is in `/usr/share/common-licenses/LGPL'.