[mythtv] "ffmpeg resync" changes

[Matt]

Hello,

   I just had a general question.  When I see Isaac committing a
change, such as 8200 (http://cvs.mythtv.org/trac/changeset/8200), and
it says that it's an ffmpeg resync.  What exactly does that mean?  Is
it that there's been a change in the ffmpeg code that Issac is
accounting for in myth?  Just curious... I read the commits list
almost everyday, so I can have a better understanding of what's going
on in myth and I see this one pop up from time to time.

Thanks!
Matt