[MPlayer-users] How do I avoid YV12 <-> BGR 16 bit conversion on playback

[cmisip]

I get this output on playback.

VDec: vo config request - 320 x 240 (preferred csp: Planar YV12)
Could not find matching colorspace - retrying with -vf scale...
Opening video filter: [scale]
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
No accelerated colorspace conversion found
SwScaler: using unscaled Planar YV12 -> BGR 16-bit special converter
VO: [fbdev] 320x240 => 320x240 BGR 16-bit

I am playing the video in a zaurus 5600 so I dont have much cpu cycles
to spare.  I read that doing software scaling realtime is a big cpu
hit.  I was wondering If I need special encode parameters to prepare the
video so that this colorspace conversion is not needed on playback.  

Thanks for any info.