[MEncoder-users] broken mencoder options (was: High quality encoding of anime and broken mencoder options)

[Jorge Peixoto de Morais Neto]

On Tue, 11 Mar 2008 11:10:11 +0100
Reimar Döffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de> wrote:

> On Sun, Mar 09, 2008 at 03:32:39PM -0300, Jorge Peixoto de Morais Neto wrote:
> > 2) the option vrc_override is broken (tested on mencoder from SVN
> > 13/02/2008). I have found other people on the internet complaining
> > about this.
> > 
> > #High quality encoding of anime:
> > [anime0]
> > lavcopts=vcodec=mpeg4:keyint=300:vmax_b_frames=2:vb_strategy=2:brd_scale=2:mbd=2:trell=yes:v4mv=yes:last_pred=3:predia=3:dia=3:mbcmp=2:cbp=yes:preme=2:vqcomp=0.6
> > 
> > #Even higher quality encoding of anime (but slower):
> > [anime1]
> > lavcopts=vcodec=mpeg4:keyint=300:vmax_b_frames=2:vb_strategy=2:brd_scale=2:mbd=2:trell=yes:v4mv=yes:last_pred=3:predia=3:dia=3:mbcmp=2:cbp=yes:preme=2:vqcomp=0.6:mv0=yes
> 
> You seem to be doing one-pass,
I do 2-pass encoding. I add vpass=1:turbo in the first pass, and
vpass=2 in the second pass.

> vrc_override AFAICT only works on the
> second pass. Can you test? If you confirm, I will update the
> documentation.
From the documentation:

        vrc_override=<options>
              User  specified  quality  for  specific parts (ending, credits, ...) (pass 1/2).  The options are
              <start-frame>, <end-frame>, <quality>[/<start-frame>, <end-frame>, <quality>[/...]]:
                 quality (2-31)
                      quantizer
                 quality (-500-0)
                      quality correction in %

From this information, I deduce that

mencoder -ovc lavc -o result.avi ../../testsource.avi -lavcopts vcodec=mpeg4:psnr:keyint=300:vmax_b_frames=2:vb_strategy=2:brd_scale=2:mbd=2:trell:v4mv:last_pred=3:predia=3:dia=3:mbcmp=2:cbp:mv0:preme=2:vqcomp=0.6:vrc_override=600,1201,28:vbitrate=640

Should get me fixed quantizer 28 for frames in [600; 1201]. This is not what I get though, as can be verified by looking in the resulting psnr_*.log