[mythtv] [mythtv-commits] Ticket #2512: Live tv studders little bit

[Daniel Kristjansson]

On Thu, 2006-10-19 at 00:03 +0100, Robin Neatherway wrote:
> > > Sorry.  Yes, the stuttering completely stops if I pause it about 3-5 seconds.
> >
> > I have exactly the same effect. I am also using DVB. And the effect is
> > not visible on all channels.
> >
> > Thomas
> 
> Basically this is a known issue that has been reported a lot of times.
> Noone seems to have the will to investigate it far enough to find a
> solution, especially seeing as it has such a simple (although highly
> irritating to have to use) workaround. It pops up on the list now and
> again, but always fades back into obscurity sadly.

There are many causes for stuttering and many have been fixed.
Unfortunately, 90% of the causes for stuttering are configuration
problems, so unless a someone mentions the things they have tried
and posts this on the users list, they are unlikely to be payed
much attention to by the developers. The particular problem where
a pause solves the problem is due to the way we ffmpeg estimates
the bitrate. In particular, it is sometimes wrong and it doesn't
update this estimate when the facts conflict with its estimate.
MythTV uses this estimate to set up the RingBuffer parameters,
and when the RingBuffer either tries to buffer too much or too
little data you get stutter.

BTW There is an active ticket for one of the stutter problems.
See #2552, I'm currently waiting for my initial patch to be tested.
I have good hardware and don't experience the stutter problems.

-- Daniel