doc: Clarify licensing issues arising from external libraries

This commit is contained in:
Diego Biurrun 2012-07-21 21:17:30 +00:00
parent bdefe22b8e
commit f30ff54200
1 changed files with 24 additions and 13 deletions

37
LICENSE
View File

@ -1,5 +1,5 @@
Libav:
------
======
Most files in Libav are under the GNU Lesser General Public License version 2.1
or later (LGPL v2.1+). Read the file COPYING.LGPLv2.1 for details. Some other
@ -38,18 +38,29 @@ for you. Read the file COPYING.LGPLv3 or, if you have enabled GPL parts,
COPYING.GPLv3 to learn the exact legal terms that apply in this case.
external libraries:
-------------------
external libraries
==================
Some external libraries, e.g. libx264, are under GPL and can be used in
conjunction with Libav. They require --enable-gpl to be passed to configure
as well.
Libav can be combined with a number of external libraries, which sometimes
affect the licensing of binaries resulting from the combination.
The OpenCORE external libraries are under the Apache License 2.0. That license
is incompatible with the LGPL v2.1 and the GPL v2, but not with version 3 of
those licenses. So to combine the OpenCORE libraries with Libav, the license
version needs to be upgraded by passing --enable-version3 to configure.
compatible libraries
--------------------
The nonfree external library libfaac can be hooked up in Libav. You need to
pass --enable-nonfree to configure to enable it. Employ this option with care
as Libav then becomes nonfree and unredistributable.
The libcdio, libx264, libxavs and libxvid libraries are under GPL. When
combining them with Libav, Libav needs to be licensed as GPL as well by
passing --enable-gpl to configure.
The OpenCORE and VisualOn libraries are under the Apache License 2.0. That
license is incompatible with the LGPL v2.1 and the GPL v2, but not with
version 3 of those licenses. So to combine these libraries with Libav, the
license version needs to be upgraded by passing --enable-version3 to configure.
incompatible libraries
----------------------
The Fraunhofer AAC library, FAAC and OpenSSL are under licenses incompatible
with all (L)GPL versions. Thus, unfortunately, since both licenses cannot be
satisfied simultaneously, binaries resulting from the combination of Libav
with these libraries are nonfree und unredistributable. If you wish to enable
any of these libraries nonetheless, pass --enable-nonfree to configure.