$ mplayer /tmp/rendered.avi 
MPlayer dev-SVN-rUNKNOWN-4.1.2 (C) 2000-2007 MPlayer Team
CPU: AMD Athlon(tm) 64 Processor 3500+ (Family: 15, Model: 31, Stepping: 0)
3DNow supported but disabled
3DNowExt supported but disabled
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled for x86 CPU with extensions: MMX MMX2 SSE SSE2

Playing /tmp/rendered.avi.
AVI file format detected.
** empty list?!
AVI: No audio stream found -> no sound.
Could not determine number of frames (for absolute seek).
VIDEO:  [mp4v]  720x480  24bpp  30.000 fps  -17179870.0 kbps (-2097152.0 kbyte/s)
xscreensaver_disable: xscreensaver wid=10485761.
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4)
==========================================================================
Audio: no sound
Starting playback...
VDec: vo config request - 720 x 480 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.50:1 - prescaling to correct movie aspect.
VO: [xv] 720x480 => 720x480 Planar YV12 
V:   0.0   1/  1 ??% ??% ??,?% 0 0 

Exiting... (End of file)