how to rotate ogg/theora video 90 degrees? (having to reencode is ok)
Hi,
since openmoko does not support hardware rotation I thought I'd
reencode videos for it and rotate them to fit to the 240x320 display
mode. This turned out to to be somewhat tricky. In the following I use
the shortest debconf9 video I could find as an example:
1) /usr/share/doc/ffmpeg/html/libavfilter.html mentions that a
-vfilters option could do rotation. However, despite documentation it
does not exist: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=594108
2) trying to read generate ogg/theora with mencoder segfaults:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=594110
3) Finally on the #theora IRC channel I was adviced to use both
mencoder and mplayer with an intermediate file.
wget http://ftp.acc.umu.se/pub/debian-meetings/2009/debconf9/low/1050_Lightning_talk_Redirecting_require.ogv
mencoder 1050_Lightning_talk_Redirecting_require.ogv -oac pcm -ovc lavc -lavcopts vcodec=ffvhuff -vf scale=320:240,rotate=1 -o output.avi
ffmpeg -i output.avi -acodec libvorbis output.ogv
almost works in debian unstable. The only problem is that some video
frames are lost => The audio plays normally but last few seconds of
video are not played at all and video generally lacks behind audio.
Given the example file above, can anybody come up with a set of
commands that work in debian (stable, testing or unstable) and have
working av sync?
(Please do not suggest me to get potentially non-free stuff from
http://debian-multimedia.org/ -- I don't want to rely on software that
can not be included in debian if at all possible.)
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