[mythtv] Jitter with time stretch

[David Engel]

On Mon, Jul 16, 2018 at 11:59:46AM -0400, Peter Bennett wrote:
> On 07/16/2018 11:37 AM, David Engel wrote:
> > > I already have a flag stored in the decoder and accessed from mythplayer
> > > using "decoder->GetfpsMultiplier()" It takes values 1 or 2, 1=normal,
> > > 2=doubled frames as with mediacodec.
> > Excellent!
> > 
> > > I am currently using fpsMultiplier only in AVSync where frame_delay is
> > > calculated from frame_interval. I need to take that out and change the
> > > calculation of frame_interval itself to use fpsMultiplier instead.
> > So are you going to make the avsync_predictor_enabled change then or
> > do you want me to do it?  I have time for it today.
> I have created a new patch that changes frame_interval calculation, and
> attached it to the ticket. I also set the buffers to 8 instead of 4. With 4
> buffers there still was a slight jiggle in the 2x speedup playback, that is
> gone with 8 buffers. See what you think.

I already noticed the new patch and am about to build.

> FF seems to be working OK with this patch. The failure is rather random. The
> re-init handles it with a slight pause when it does happen. Do you think
> there is any point in trying to change FF to use software decoding?

I used my Shield almost exclusviely for watching yesterday.  There are
still some rough edges like the IllegalStateException and hangs when
left in the background for too long, but we're definitely very close
being able to use it full time.  In fact we're close enough that I
think I'm going to pick up one or two Shields for my mom on the Prime
Day sale.

> I think I am almost ready to commit this. First I will do some testing on
> Linux with different playback profiles, and on raspberry Pi, to make sure
> nothing got broken. I want to split it into a few commits to separate some
> things that were not exclusively for mediacodec, and separate out the FFmpeg
> fix. Anything that is logically separate I will make a separate commit. I
> see no sign that Aman plans to commit the FFmpeg fix. That needs to be
> committed to the MythTV private FFmpeg repository as well.

Sounds good on the commit.  Maybe give Aman a gentle reminder.  If he
got busy with other things, he could have just forgotten.

David
-- 
David Engel
david at istwok.net