[mythtv] AVSync2 Improvements

[David Engel]

On Tue, Feb 12, 2019 at 10:56:31AM -0700, John P Poet wrote:
> On Tue, Feb 12, 2019 at 10:31 AM David Engel <david at istwok.net> wrote:
> 
> > On Tue, Feb 12, 2019 at 11:01:19AM -0500, Peter Bennett wrote:
> > > I have been using the latest patch
> > https://code.mythtv.org/trac/attachment/ticket/13383/20190208_1644_catchup_plus.patch
> > > for a couple of days and it looks good now.
> > >
> > > Mark- you said you may have some improvements - I plan to commit it
> > anyway
> > > and those can always be done afterwards.
> > >
> > > You said that making the wait into a series of short waits may improve
> > > things. Currently on a desktop system everything is between -5 and +5 ms
> > so
> > > I don't know if much improvement is possible. Also on thinking about it I
> > > don't know how that would help, if the operating system is going to delay
> > > resuming a process on one wait, would it be less likely to delay it on a
> > > bunch of smaller waits?
> > >
> > > If I don't hear anything back I will commit that patch to master and
> > > fixes/30.
> >
> > Peter,
> >
> > Perhaps you must have missed my report on IRC.  The 0208 patch causes
> > problems with live TV.  When starting live TV or changing channels,
> > playback stutters badly until it is briefly paused or skipped back.  I
> > don't know if earlier patches did this since I didn't test them on
> > live TV.
> >
> 
> I have not had a chance to try the last couple of patch candidates.  For
> me, that Live TV issue is "long standing" and seems to depend on the source
> material -- mpeg2 is fine, but H.264 with large key-frame distance has that
> behavior.  In other words, the new avsync does not 'create' that problem,
> at least for me.

In my experience, it used to be an issue but hasn't been since v30 and
the already committed avsync2.  Playback syncs up fairly quickly now
(without the current patch) whereas before it could take minutes to
sync up.

David
-- 
David Engel
david at istwok.net