ffmpeg -i bemeneti.ogg kimeneti.flv

kim@debiankim:~$ ffmpeg -i /home/kim/Firefox_screenGrab.ogv /home/kim/Firefox_screenGrab.flv
FFmpeg version SVN-r0.5.6-4:0.5.6-3, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --extra-version=4:0.5.6-3 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libdirac --enable-libgsm --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --disable-stripping --disable-vhook --enable-runtime-cpudetect --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libfaad --enable-libdc1394 --enable-shared --disable-static
  libavutil     49.15. 0 / 49.15. 0
  libavcodec    52.20. 1 / 52.20. 1
  libavformat   52.31. 0 / 52.31. 0
  libavdevice   52. 1. 0 / 52. 1. 0
  libavfilter    0. 4. 0 /  0. 4. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Dec 31 2011 15:16:11, gcc: 4.4.5
Input #0, ogg, from '/home/kim/Firefox_screenGrab.ogv':
  Duration: 00:05:47.53, start: 0.000000, bitrate: 574 kb/s
    Stream #0.0: Invalid Codec type -1
    Stream #0.1: Video: theora, yuv420p, 1024x768, PAR 1:1 DAR 4:3, 15 tbr, 15 tbn, 15 tbc
Output #0, flv, to '/home/kim/Firefox_screenGrab.flv':
    Stream #0.0: Video: flv, yuv420p, 1024x768 [PAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 90k tbn, 15 tbc
Stream mapping:
  Stream #0.1 -> #0.0
[flv @ 0x88625d0]removing common factors from framerate
Press [q] to stop encoding
frame= 5212 fps= 17 q=24.8 Lsize=   12993kB time=347.47 bitrate= 306.3kbits/s
video:12912kB audio:0kB global headers:0kB muxing overhead 0.632136%
kim@debiankim:~$