[mythtv] Broken AV sync after mythtranscode

Adam Egger mythtv2005 at bdam.de
Sun Dec 25 18:06:12 EST 2005

On 12/25/05, Geoffrey Hausheer <mythtv0368 at phracturedblue.com> wrote:

> Basically, what I'm calling the 'big hammer', is some code that kicks
> in when all other hope is lost.  It just throws away all timestamps in
> the file, and uses its internal running count.  From then on, there is
> no attempt to keep AV in sync anymore.  This happens when the PTS
> jumps by more than 20 frames at once.  After that, it is unreasonable
> to try to fill in the empty frames.  If this only happens to the
> video, but not to the audio, the stream is broken, and there's not
> much we can do.  The 'big hammer' is better than nothing.  However, if
> all streams have the same (or similar) jump at the same time, we can
> just reset the offset and move on.  This is what I need to code.
> Unfortunately, because audio and video are processed independently, it
> isn't that easy to detect this case.  I'll need to think about the
> best way to do it.  I'll let you know after I come up with a
> reasonable fix.

Geoff, thank you very much for r8381 ;) This one fixed almost all my
A/V issues. All my transcoded files lose 40% of data and are perfectly
synchronous :D Great!
The only small issue I still have are some green frames on every cut
point. Is it a known issue? Here's a small (1MB) transcoded file with
a cut point at the beginning:

Thanks again,

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