[MPlayer-dev-eng] TOOLS : a new shell script to rip DVD and encode DIVX

[Corey Hickey]

Seb wrote:
> Hi,
> 
> This is a new interactive shell script to rip DVD and encode 
> DIVX with the best options and parameters (I think).
> You can rip, encode audio, encode video, separately into
> different sessions. Type makedivx.sh --help for options.
> You can put it in the TOOLS directory.
> 
> Seb.
> 

(from the script)
-lavcopts vcodec=mpeg4:vpass=1:vbitrate=$rate:vhq

Your lavcopts could be tuned some.... mbd=2 should be used instead of
vhq, and trell is (in my opinion) a must. Other options that increase
quality significantly, in my experience, are:
cmp=2:subcmp=2
vmax_b_frames=1
v4mv
Some parameters that often help PSNR slightly are:
mv0 (requires mbd=2)
cbp (requires trell)


Also, the script has no provisions for encoding NTSC DVDs (I don't blame
you; I don't know much about PAL).
1. It doesn't use -ofps, which is needed for encoding 23.976fps
   progressive DVDs.
2. There's no way to specify inverse-telecine operations. Newbies might
   be likely to see the "deinterlace" option and think that is what they
   should use.


For best results, cropping out black bars is absolutely necessary. After
that, the picture must be scaled so both axes are multiples of 16 (and
to a size appropriate for the intended encoding bitrate).


Hmm.... I don't see anything else to comment on, yet. You've taken on a
difficult project. :)

-Corey