[MPlayer-users] reducing pixelation in high movement video.

[steven]

I am looking for advice on how to improve the quality of my finished
video in particular reducing pixelation and suggestion of the best
codecs/ encoding parameters to use in my application.

I am recording to mini dv tape using an externally mounted camera with
560 lines resolution.  The camera is mounted on my helmet while mountain
biking.

I am capturing the video to my pc and editing it using kino.  I then
output that from kino to a dv file (where the output still looks good).
I am then converting it using mplayer to 2 different types of output.

The first output type is to DVD for playback on TV so file size is not
an issue. The second is to file for download over internet.  Here I am
looking to use a widely used codec so my friends can play it, and am
happy to trade off longer encoding times for better quality but would
like to keep file size down.

For the first (DVD) I used the following (based on guidelines from
mplayer manual.

mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=dvd -vf
scale=720:576,harddup -srate 48000 -af lavcresample=48000 \
-ofps $FPS -o $OF $IF \
-lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:
vbitrate=8000:keyint=15:trell:mbd=2:precmp=2:subcmp=2:cmp=2:
dia=-10:predia=-10:cbp:mv0:vqmin=1:lmin=1:dc=10

Even with this high bitrate I get a lot of pixelation.  For a 30min
video my file is 1.5GB.  I have tried fiddling with the parameters but
keep getting rc buffer underflow errors so have stuck with the above.
Any suggestions on how to improve quality would be most appreciated.


For the downloadable file version I have tried many things including
mpeg4, Xvid, wmv and mpeg1video, in both single pass and 2 pass.  The
mpeg1 results in large file sizes because I cannot reduce frame rate
below 25fps.  I have just read about x264 but have not yet had an
opportunity to try it.  I am mostly using a frame size of 352x288 to try
and reduce file size.

I am happy to trade of longer encoding times if it will result in better
quality for the action shots. Again, any suggestions on how to reduce
pixelation would be most appreciated.

Thank you and regards
Steven