[Theora] trying to encode from dvd using mplayer

David Kuehling dvdkhlng at gmx.de
Tue Dec 14 01:21:48 PST 2004

>>>>> "zikzak" == zikzak  <zikzak at tele2.fr> writes:

> I added the ti.sharpness and the keyframe you mentioned before and I
> must say that it is a big help.  I have a much better image in the
> output file and I can increase the video quality option one more step
> (from 6 to 7 in my test).  Does the new keyframe value is saving bytes
> ?  

Don't know.  Just used those values since they are closer to the default
keyframe distances used by mencoder for encoding to MPEG4/DivX.  In
theory it should give some improvements.  Too large keyframe distance
might cause certain artefacts, but since I was never able to spot one of
these, I assume that Theora is designed for this kind of use...

If you have particularly noisy input data you might also try to play
around with `ti.noise_sensitivity'...  but using mplayer's denoise
filter (for example: `-vf hqdn3d=2:2:2') might give better quality.

BTW encoding time can be shortened a lot by using the theora-mmx branch.
Last time I tried it, it worked quite well and the resulting files could
be played back flawlessly with the normal theora.

Try:  (not sure about that)

  svn co http://svn.xiph.org/trunk/theora-mmx   

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