[MEncoder-users] Can mencoder be used to tell me whether a video contains high action scenes

[David Smith]

I need to convert to flv.  So what's the best way to do "crf"
using libavcodec options?  I see things like vqscale, vme, last_pred, preme,
qpel, temporal complexity masking, etc., but I have no idea how those all
fit together.  I have seen a few command line examples, but not real-world
examples of what these actually "mean".  The one I am currently using is:

mencoder IN.rm -o OUT.flv -sub captions.srt -oac mp3lame -lameopts abr:br=56
-srate 22050 -ovc lavc -lavcopts
vcodec=flv:vbitrate=196:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -mc 1 -of lavf
-vf harddup

It yields good results, but I am trying to find out if it's really
optimized.  I want to dynamicaly adjust the vbitrate because I just know
some of the files going in have very low bitrates, and some have very
high, rather than a "one size fits all" approach to bitrate.  Hope I'm
explaining this right.

Thanks again for any advice in this area of bitrate optimization.

>
> > If the vid contains a lot of movement then want to program the
> > converter to set a higher bitrate (or other parameters).
>
> Motion is only one of the reasons a video may be easy or difficult to
> compress, so that would not be useful.
>
> Your best bet is to look into the CRF option of x264.
>