• 1
  • 41
  • 42
  • 43(current)
  • 44
  • 45
  • 50
24p and audio sync issues
Nope, i have a Nvidia (680).

For me it's the contrary, i tried to played with every other options but his one, and couldn't get rid of the delay.
It's thanks to this topic and someone talking about this option being a game changer too, that i tried to change it.
And voilà, perfect sync Smile

This 24p issue is quite complex, and i think there is a lot where something can goes wrong and bring this problem to the user..

Just to be clear, the symptoms before adding the pause were this :

- big delay when starting playback
- sync back to normal when hitting "left" during playback (30 sec leap backward)
- buig delay back when pausing and playing again
So i could'nt use the delay global settings, because this big delay was only occurring at the playback launch or when going of pause.

For those who have these exact symptoms, pause before changing refresh might be the solution.

And here are my settings, if it can help anyone (i'll translate them from french to english so could be a little different from reality) :

SYSTEM / VIDEO OUTPUT :
- resolution : 1920x1080P
- simulate full screen with window : false
- vertical sync : always activated

VIDEO / PLAYBACK :
- adjust refresh rate to video : always
- pause during refresh rate frequency change : 2 sec
- playback sync with display : false

VIDEO / ACCELERATION :
- rendering method : DXVA
- decoding method : hardware accelerated
- activate hardware acceleration (DXVA2) : true
Reply
Ouch!
I spoke too soon, i still have some big lip-sync issues :

- after pausing/resuming a video, huge delay is back
- after a while even without pausing, it seems a delay is appearing

When it comes to playback, why can't it be as simple as with a Dune? Sad
Reply
Well i finally could get rid of my lip sync issues!

It's off topic, but as it might interest somebody I'll post my config :

SYSTEM / VIDEO OUTPUT :
- Display mode : Full screen
- Resolution : 1920x1080P
- Simulate full screen with window : no
- VSYNC : always

VIDEO / PLAYBACK :
- Adjust refresh rate : always
- Pause during refresh rate change : 1 sec
- Sync playback with display : no

VIDEO / ACCELERATION :
- Rendering method : DXVA-HD
- Decoding method : hardware accelerated
- Activate hardware acceleration (DXVA2) : yes
Reply
But if you don't sync playback with display then you're not running 24p. Correct me if I'm wrong here... Big Grin
Reply
(2014-10-22, 15:42)Xophile Wrote: But if you don't sync playback with display then you're not running 24p. Correct me if I'm wrong here... Big Grin

that's wrong. sync playback to display defines the source of the clock
Reply
It's the "adujst refresh rate" option that makes it run in 24p.

Some feedback, well i'm not quite done yet with lip-sync issue, arg.

When i start playback, audio is synced, when pausing/resuming, audio stays synced, but a desync seems to slowly occur in the length of the playback..

I think I'm going to try window mode with Aero deactivated.
Reply
Yes, but without syncing it to the refresh rate it is not doing what you think it is doing. Not quite.
Reply
(2014-10-22, 23:57)_Shorty Wrote: Yes, but without syncing it to the refresh rate it is not doing what you think it is doing. Not quite.

please try to explain what you think it does and how this is related to a/v sync
Reply
My reply was in response to djoole. I don't think vsync-off, in and of itself, has anything to do with a/v sync. My point was simply that having a 24 Hz refresh and 24 fps material does not necessarily give you video playback that is correct, since vsync is off and that means each frame of video isn't necessarily lining up with the display's frames. If you're not syncing playback to the display's refresh then I don't even see the point in switching to 24 Hz refresh in the first place.
Reply
24p material has a frame time of 41ms. it is very unlikely that system clock drifts that much in 90 min playing time that this would result in a frame drop/dupe. if the displays refresh rate is not accurate enough audio pass though has to drop packets.
the actual use case for sync playback to display is for refresh rate does not match fps exactly and audio is resampled. like PAL speeds up 24p material for 50Hz.
Reply
So you're telling me it wouldn't be a sea of constant tearing?
Reply
sync playback to display has nothing to do with tearing. if driver syncs to vblank (this is a different story) there can't be any tearing
Reply
Users continue to post their problems and hacks/solutions, but I am wondering if this issue is being addressed at the development level at all with the addition of new features.

I must admit, I finally gave up after trying numerous configurations and went back to 60p playback. Using Reclock as the audio renderer seemed to be the best answer but I'm wholly convinced the processing of my 60F7500 Samsung LED is to blame. Perfect sync appears impossible with some setups.
Reply
If playback is not synced to the display then when does the flip to the next media frame happen? Does it not occur on time relative to itself without regard for the display? Doesn't that pretty much guarantee tearing?

Warner, how could your display's electronics have anything to do with it? The problem is happening in the playback software before going out to your display. Your display is merely influencing decisions made concerning the setup of playback.
Reply
(2014-10-23, 22:18)_Shorty Wrote: If playback is not synced to the display then when does the flip to the next media frame happen? Does it not occur on time relative to itself without regard for the display? Doesn't that pretty much guarantee tearing?

you are referring to "sync to vblank" which is handled by the driver. if "sync playback to display" is checked, vertical retrace drives the clock
Reply
  • 1
  • 41
  • 42
  • 43(current)
  • 44
  • 45
  • 50

Logout Mark Read Team Forum Stats Members Help
24p and audio sync issues8
This forum uses Lukasz Tkacz MyBB addons.