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 FFmpeg
sources to build the objects out of tree. To do this, use an absolute
path when launching 'configure', e.g. '/ffmpegdir/ffmpeg/configure'.

2) Then type 'make' to build FFmpeg. On BSD systems, type 'gmake'
instead of 'make'. You may need to install GNU Make 3.81 first.

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