[LAU] OT - Audio and Video Synch

[Len Ovens]

On Sat, 19 Oct 2013, Ralf Mardorf wrote:

> On Fri, 2013-10-18 at 15:38 -0700, Len Ovens wrote:
>> So if you are looking from a distribution POV, you have no control of
>> what the audience will play your video on.
>
> Assumed you would have the perfect player, the picture is absolutely
> identical to the original, the sound is completely equal to it's source,
> on every consumers gear, then light still is faster than sound. Do you
> sync for the smart phone or for the drive-in theater?

Yes of course. The brain is used to dealing with audio lag at varying 
distances. I was playing around with VLC which has a sync control. It 
seems I could set it to be off a bit but my brain seems to correct it with 
in some seconds... Or maybe every time I change the sync the audio and 
video restart from a known point of sync and then drift...

As you said before, the brain notices leading sound much sooner than 
lagging sound. That would be the way it is in nature. The drive-in 
theaters I have seen have in-car sound (often using the car's radio), so 
the delay is minimal. I wonder if indoor theater operators set the audio 
ahead just a bit so it hits the second or third row in sync. It would 
probably mess with the surround sound too much. I will say I have not 
noticed sync problems in the theater even though we always sit at the back 
as my son doesn't see well above horizontal.


--
Len Ovens
www.ovenwerks.net