Audio sync problems on LAV filters (1 Viewer)

[alexdepalma]

Hi all.
since few versions Im experiencing audio syn problems using LAV.
I used to have LAV audio sync settings set around 190ms. Now, every time I play a video file or Tv channel, even if I set this delay on lav to 190, at the time I open a vide or tv vhannel, the delay is reseted to 0ms. if manually changed, all goes fine, but on new oppening it goes again to 0.
tried new video delay options in MP config, but seems to have no efect on videos or tv.
maybe its not related with 1.21 pre but problem came few months a go. opening video file or what ever, seems to always reset LAV audio setting to 0ms.
so changing LAV audo parameter, seems to memorize the inserted value, but on opening of a video content within MP, the value goes 0, lav Audio config outside MP also goes to 0.so the 0 figure is memorized for the LAV config to be used in different programs

how can i trouble shoot this?

logs attached for a video file. Before playback, LAV was set to 190ms audio delay. On video start, lav opens on 0ms.

 

[Owlsroost]

@Sebastiii - any thoughts?

 

[Sebastiii]

I need to test again because we talk about this with @daWooky about the delay reset or not, I didn't remember exactly.
From memory, it should keep the delay set in config but I'm not sure anymore, will try to find where we talk about it

Edit : found the thread : [WiP] - Audio delay when using LAV Audio codec
So yes each start reset the delay to 0

 

[alexdepalma]

I need to test again because we talk about this with @daWooky about the delay reset or not, I didn't remember exactly.
From memory, it should keep the delay set in config but I'm not sure anymore, will try to find where we talk about it

Edit : found the thread : [WiP] - Audio delay when using LAV Audio codec
So yes each start reset the delay to 0

Yes and kept for the rest. And in my setup, the inserted value is not used. so, my recomendation is, may be, ad a tickbox in MP config to enable the function. On stop, the corrected or fine tuned value should be used, not zero or the defaulted. And the steps on the MP sliding bar should be in quarts of ms and not a full entire ms which seems to me too much. May be the max sliding could be 300 or 400 ms and split the rest in minor ms with neutral point on the inserted value in MPconfig (in any of my tvs and projector the delay is higher than 200ms.
I suppose the intention is to sync the processing delay of the tv or projector. So there could be a suggestion, to detect the display Name and adjust a delay for each. that would be absolutely perfect. Minimum for 2 displays and automaticaly adjust the delay on a function of the used display and in the event of dual display playback, made the average of both values. and leave the GUI sliding bar to fine tune. in this case, without memorizing the value.

And in may opinion, the set value should be the starting point and the fine tuned one (inside the MP GUI) the one finally recorded or used. The processing time of the display (TV or projector) depends on the screen it self and the "improvements" activated on the tv. That means, rarely will be changed, so the fine tuned value on the GUI will be the most accurate and the value inserted permanently on LAV for furder use. On the sliding bar I would also appreciate the actual value in figure to get an idea of the actual correction inserted. Many times I fine tune in very small amounts like 190 or 197... or 195ms. The gui must allow this very fine tune. 100ms ot 200 ms is too much. May be 2 sliders or a tick box for smaller amounts or simply a more steps would be good.

hope it helps and can be corrected.

Thanks @Sebastiii all my best wishes for the new year.
Alex

 

[Sebastiii]

All my best wished for the new year too
It should make a lot a modification in code

About this setting:

It's the delay step (need to change wording like "Delay interval step"), so if you want to have a step for each 10 ms (from GUI) you need to set 10 there in MP config.
For example, I have set mine to 400 to have each step of 400 ms because some video of mine has 1 or 2 sec of delay.

I suppose the quick addon that can be made is to add on option to keep the delay set in MP or from LAV Audio tray (stored) for each video/tv playback start.

What do you think?

 

[alexdepalma]

Keep the value is the best. and thanks for the tip. didn't know it was the step. May be change the text to Step delay interval will be more adequate. And yes, please, remember the value is the best. And an figure about the actual total delay. And may be a tick box and the actual figure next to the bar is not a big change.
If the box in MP config is the step. The starting delay value set in Lav will be a good add.

 

[alexdepalma]

The minimum step value is 10. Can you set it to 5? and additional box for the initial delay?
In my case ill start with 190 value with 190 ms of delay and a 5 ms step for fine tune.
and finally. The same thing for TV can be added?

 

[Sebastiii]

Will try to see what can be done

This will maybe take a while to have this coded, I can try but not much time but will ping you here for you to test
Maybe it's not that hard to add but need some code for sure.

What I can try is :
1- To set a bool to enable or not the resetting on start
2- Reduce the minimal value to 5
3- Trying to set a value start (like your 190 ms)

But to be able to play with this audio delay for LAV, the filter must be loaded in graphbuilder and in MP based on other setting the filter is removed added (on codec change) or on start etc. so it's surely not so easy to change the current code.

About the TV part, I was thinking it was already working but maybe it is not after all lol

 

[alexdepalma]

May be TV is working but as the value is restet to 0 every time and I need a permanent 190 on TV for his own delay, i don't see the change. The annoying problem is that for me to correct the TV delay I use in lav audio codec a 190ms delay. Thats permanent. And may be a very small amount to fine tune. Now I have a permanent 0. And all my playbacks are wrong. Before 1.19. All was fine. This add is really a good idea. 2 or 4 secs delay is probably due to a wrong video file and not a TV or projector lag, wich is actually the common thing, and the real power of the feature when audio goes to amp and video to a screen and things are processed separately.

I really hope you can fix it or alow to disable the feature and continue with the old system, adding the delay to LAV directly. With the actual system. Now, every playback is wrong. I didn't notice this new feature and I have been going crazy to fix it.... and actually evaluating even other software....



Many thanks!

 

[Sebastiii]

I have done some adding code without testing, are you able to test (will upload a build here asap)?
Thanks.