1) Type './configure' to create the configuration. A list of configure
options is printed by running 'configure --help'.

'configure' can be launched from a directory different from the Libav
sources to build the objects out of tree. To do this, use an absolute
path when launching 'configure', e.g. '/libavdir/libav/configure'.

2) Then type 'make' to build Libav. GNU Make 3.81 or later is required.

3) Type 'make install' to install all binaries and libraries you built.

NOTICE

 - Non system dependencies (e.g. libx264, libvpx) are disabled by default.

 - The default cflags include -g, if you want lean libraries you can either
   pass --disable-debug or strip the debug symbols at a later time.