ffmpeg version 0.9.4, Copyright (c) 2000-2014 the FFmpeg developers
  built on Mar  5 2015 13:08:36 with gcc 4.6.3
  configuration: --prefix=/usr/local/ffmpeg --enable-shared --enable-nonfree --enable-gpl --enable-pthreads --enable-libopencore-amrnb --enable-decoder=liba52 --enable-libopencore-amrwb --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-version3
  WARNING: library configuration mismatch
  avutil      configuration: --extra-version='4:0.8.16-0ubuntu0.12.04.1' --arch=amd64 --prefix=/usr --libdir=/usr/lib/x86_64-linux-gnu --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --enable-runtime-cpudetect --enable-libfreetype --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/x86_64-linux-gnu --enable-shared --disable-static
  avcodec     configuration: --extra-version='4:0.8.16-0ubuntu0.12.04.1' --arch=amd64 --prefix=/usr --libdir=/usr/lib/x86_64-linux-gnu --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --enable-runtime-cpudetect --enable-libfreetype --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/x86_64-linux-gnu --enable-shared --disable-static
  avformat    configuration: --extra-version='4:0.8.16-0ubuntu0.12.04.1' --arch=amd64 --prefix=/usr --libdir=/usr/lib/x86_64-linux-gnu --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --enable-runtime-cpudetect --enable-libfreetype --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/x86_64-linux-gnu --enable-shared --disable-static
  swscale     configuration: --extra-version='4:0.8.16-0ubuntu0.12.04.1' --arch=amd64 --prefix=/usr --libdir=/usr/lib/x86_64-linux-gnu --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --enable-runtime-cpudetect --enable-libfreetype --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/x86_64-linux-gnu --enable-shared --disable-static
  libavutil    51. 32. 0 / 51. 22. 2
  libavcodec   53. 42. 4 / 53. 35. 0
  libavformat  53. 24. 2 / 53. 21. 1
  libavdevice  53.  4. 0 / 53.  4. 0
  libavfilter   2. 53. 0 /  2. 53. 0
  libswscale    2.  1. 0 /  2.  1. 0
  libpostproc  51.  2. 0 / 51.  2. 0
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...

Use -h to get full help or, even better, run 'man ffmpeg'