ffmpeg -i input.mkv -c:v libxvid -s:v 640x360 -b:v 1100000 -c:a libmp3lame -ac 2
ffmpeg version N-39267-g4082198 Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar 25 2012 20:28:42 with gcc 4.6.2
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
-enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
libxvid --enable-zlib
  libavutil      51. 44.100 / 51. 44.100
  libavcodec     54. 12.100 / 54. 12.100
  libavformat    54.  3.100 / 54.  3.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 65.102 /  2. 65.102
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 10.100 /  0. 10.100
  libpostproc    52.  0.100 / 52.  0.100
Input #0, matroska,webm, from 'input.mkv':
  Metadata:
    creation_time   : 2011-09-19 16:30:37
  Duration: 00:21:30.33, start: 0.000000, bitrate: 6043 kb/s
    Stream #0:0(eng): Video: h264 (High), yuv420p, 1280x720, SAR 1:1 DAR 16:9, 2
3.98 fps, 23.98 tbr, 1k tbn, 47.95 tbc
    Stream #0:1: Audio: ac3, 48000 Hz, 5.1(side), s16, 448 kb/s (default)
File 'out.avi' already exists. Overwrite ? [y/N] y
w:1280 h:720 pixfmt:yuv420p tb:1/1000000 sar:1/1 sws_param:
[scale @ 0000000004206B20] w:1280 h:720 fmt:yuv420p sar:1/1 -> w:640 h:360 fmt:y
uv420p sar:1/1 flags:0x4
Output #0, avi, to 'out.avi':
  Metadata:
    creation_time   : 2011-09-19 16:30:37
    ISFT            : Lavf54.3.100
    Stream #0:0(eng): Video: mpeg4 (xvid / 0x64697678), yuv420p, 640x360 [SAR 1:
1 DAR 16:9], q=2-31, 1100 kb/s, 23.98 tbn, 23.98 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, 2 channels, s16 (de
fault)
Stream mapping:
  Stream #0:0 -> #0:0 (h264 -> libxvid)
  Stream #0:1 -> #0:1 (ac3 -> libmp3lame)
Press [q] to stop, [?] for help
Input stream #0:1 frame changed from rate:48000 fmt:s16 ch:6 to rate:48000 fmt:s
16 ch:2
frame=   27 fps=0.0 q=6.0 size=     180kB time=00:00:01.12 bitrate=1310.0kbits/s
frame=   56 fps= 55 q=6.0 size=     393kB time=00:00:02.33 bitrate=1377.9kbits/s
frame=   86 fps= 57 q=6.0 size=     649kB time=00:00:03.58 bitrate=1481.7kbits/s
frame=  115 fps= 57 q=6.0 size=     868kB time=00:00:04.79 bitrate=1481.7kbits/s
frame=  144 fps= 57 q=6.0 size=    1076kB time=00:00:06.00 bitrate=1468.1kbits/s
frame=  174 fps= 57 q=6.0 size=    1311kB time=00:00:07.25 bitrate=1480.0kbits/s
frame=  187 fps= 57 q=6.0 Lsize=    1413kB time=00:00:07.88 bitrate=1468.1kbits/s