Public bug reported:

Binary package hint: ffmpeg

There has recently been a great deal of work done on improving the
Theora encoder (the "Thusnelda" branch). The resultant streams are still
within the spec, and the reference decoder still works on them, but
ffmpeg's decoder doesn't implement the full spec. Until recently, this
wasn't a problem, because the encoder didn't use those extensions. Now,
however, this means that ffmpeg doesn't support the (compliant) streams
produced by the new and improved encoder.

A sample is available via:
http://web.mit.edu/xiphmont/Public/theora/demo5.html ; I'm not attaching
it, since it's about 16MB, but here's a simple sequence to see the
problem:

$ wget http://web.mit.edu/xiphmont/Public/theora/matrix-580.ogg
$ ffmpeg -y -i matrix-580.ogg -vcodec huffyuv theora-old.avi
$ wget http://web.mit.edu/xiphmont/Public/theora/test50-skip5-acdc16.ogg
$ ffmpeg -y -i test50-skip5-acdc16.ogg -vcodec huffyuv theora-new.avi

As the files will be rather large (they're lossless), just hit 'q' after
a second or two has been encoded, so that ffmpeg will truncate the
output. Play both the theora-old.avi and theora-new.avi in something
supporting HuffYUV (mplayer or vlc will work). theora-old.avi will play
back properly; theora-new.avi will be severely corrupted.

Neither of the input files are corrupted; this can be tested by playing
them in mplayer, vlc or totem, all of which render the stream properly
on my system. (Possibly because they share backends, but in any case,
this should be easy to check.)

I am running ffmpeg 3:0.cvs20070307-5ubuntu7.1+medibuntu1 on Ubuntu
Hardy.

** Affects: ffmpeg (Ubuntu)
     Importance: Undecided
         Status: New

-- 
ffmpeg does not support Theora extensions
https://bugs.launchpad.net/bugs/259087
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