[Theora] ffmpeg2theora with mmx patches is available on konvalo.org

[Ivan Popov]

On Wed, Mar 30, 2005 at 09:02:25PM +0200, Ivan Popov wrote:
> It contains also all of the frequently used functions needed by an encoder,
> so you would prefer it to the theora-encoder script unless you need
> sophisticated video filtering.

Looking at movies from Prelinger Archives, many of them are
telecined and interlaced.

ffmpeg2theora does not seem to do detelecining,
nor can mplayer do that (so it is impossible to supply the filtering args
to theora-encoder).

Good results at recoding to Theora can be achieved by consequent application of

 mencoder -vf filmdint -fps 29.97 -ofps 23.976 \
          [possibly more filtering] \
          -ovc lavc -lavcopts vbitrate=<a-high-bitrate> \
          [-ovc copy does not produce a valid result] \
          -o intermediate.avi \
           ...

 theora-encoder ... intermediate.avi

(ffmpeg2theora seems to have problems accepting the intermediate avi file
as input, the resulting sound is broken)

Do not forget -s and -S pixel aspect ratio options,
very often pixels are not suare.

Cheers,
--
Ivan