[MPlayer-dev-eng] Potential source of A-V sync issues

[Guillaume POIRIER]

On 2/1/06, Matthias Hopf <mat at mshopf.de> wrote:
> Hi all,
>
> I'm currently rewriting part of the mencoder main loop as I get a whole
> bunch of skipped + duplicated frames (typically leveling out) when
> encoding some TCed material (transport streams) to avis. I'm already
> testing an early patch, that works very well for me, but I really have
> to rewrite it (it was only a hack so far).
>
> While analyzing the code, I noticed, that skip_flag is initialized with
> 0 at the begining of the while (!at_eof) - but as only one frame can be
> skipped at a time, skip_flag might still be positive (but not
> negative!). The following patch moves the definition of skip_flag
> outside the main loop, but I haven't really tested it.
>
> Please ignore the v_jitter_sum variable in the patch - it is a leftover
> from my current work. The lines numbers won't match exactly as well.

I don't know anything about mencoder's code, so I can't tell you much
about your patch.

However, I'd be interested if you could upload a _short_ sample
somewhere (you could try ftp://213.144.138.186/MPlayer/incoming/) to
see if your problem is reproductible on my machine.

I'd also suggest trying Corey Hickey's patches to improve MEncoder:
http://archives.free.net.ph/thread/20060217.023945.cb6b19b8.en.html
http://archives.free.net.ph/thread/20060217.090827.3fadf13f.en.html

They have fixed one of the big problem I had with MEncoder, so they
may be of some help for you too.

Guilaume
--
Just because code is syntactically "valid" GNU C doesn't mean gcc can
always compile it.
  Steven Bosscher - 2005-01-01
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11203#c14