$ sudo mencoder file.wmv -ofps 23.976 -ovc xvid -oac copy -o file.avi
mencoder: Symbol `ff_codec_bmp_tags' has different size in shared object, consider re-linking
MEncoder SVN-r33713-4.6.1 (C) 2000-2011 MPlayer Team
success: format: 0  data: 0x0 - 0x330bed40
ASF file format detected.
[asfheader] Audio stream found, -aid 1
[asfheader] Video stream found, -vid 2
VIDEO:  [WMV3]  1280x720  24bpp  1000.000 fps  4608.0 kbps (562.5 kbyte/s)
[V] filefmt:6  fourcc:0x33564D57  size:1280x720  fps:1000.000  ftime:=0.0010
xvid: using library version 1.3.2 (build xvid-1.3.2)
Opening video filter: [expand osd=1]
Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1
==========================================================================
Opening video decoder: [dmo] DMO video codecs
Win32 LoadLibrary failed to load: /usr/lib/codecs/wmv9dmod.dll
IMediaObject ERROR: 0x82de94a  could not open DMO DLL (0x0 : 0)
Failed to create DMO filter
ERROR: Could not open required DirectShow codec wmv9dmod.dll.
You need to upgrade/install the binary codecs package.
Go to http://www.mplayerhq.hu/dload.html
VDecoder init failed :(
Opening video decoder: [dmo] DMO video codecs
Win32 LoadLibrary failed to load: /usr/lib/codecs/wmvdmod.dll
IMediaObject ERROR: 0x82de94a  could not open DMO DLL (0x0 : 0)
Failed to create DMO filter
ERROR: Could not open required DirectShow codec wmvdmod.dll.
You need to upgrade/install the binary codecs package.
Go to http://www.mplayerhq.hu/dload.html
VDecoder init failed :(
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Unsupported PixelFormat 61
Unsupported PixelFormat 53
Unsupported PixelFormat 61
Unsupported PixelFormat 53
Selected video codec: [ffwmv3] vfm: ffmpeg (FFmpeg WMV3/WMV9)
==========================================================================
audiocodec: framecopy (format=161 chans=2 rate=44100 bits=16 B/s=16002 sample-5945)
Movie-Aspect is undefined - no prescaling applied.
videocodec: XviD (1280x720 fourcc=44495658 [XVID])
xvid: par=0/0 (vga11), displayed=1280x720, sampled=1280x720
xvid: you must specify one or a valid combination of 'bitrate', 'pass', 'fixed_quant' settings
FATAL: Cannot initialize video driver.
Movie-Aspect is undefined - no prescaling applied.
videocodec: XviD (1280x720 fourcc=44495658 [XVID])
xvid: par=0/0 (vga11), displayed=1280x720, sampled=1280x720
xvid: you must specify one or a valid combination of 'bitrate', 'pass', 'fixed_quant' settings
FATAL: Cannot initialize video driver.

Exiting...