* libpostproc and libswscale are distributed under the GNU General Public
License, see the file COPYING.GPL for details. Their compilation and use
in FFmpeg is optional.
+
+* The file libavcodec/i386/idct_mmx.c is distributed under the GNU General
+ Public License. It is strictly an optimization and its use is optional.
+
+* The file libavcodec/ac3dec.c is distributed under the GNU General Public
+ License. In order for (E-)AC-3 decoding to work you need to enable GPL
+ components.
+
+* The file libavdevice/x11grab.c is distributed under the GNU General
+ Public License. X11 grabbing is optional.
+
+* The files libavcodec/jfdctfst.c, libavcodec/jfdctint.c, libavcodec/jrevdct.c
+ are taken from libjpeg, see the top of the files for licensing details.
+
+* The file libavcodec/fdctref.c is copyrighted by the MPEG Software Simulation
+ Group with all rights reserved. It is only used to create a DCT test program
+ and not compiled into libavcodec.