Frame sync with 2 Playlist - advice

Christie Pandoras Box Version 6 - Q&A

Moderator: Moderator Group

Forum rules
When asking make sure to include the operating system and the revision of Pandoras Box you are using. If your question is related to hardware, please state if you are using coolux hardware (which one) or if you built your own.

Frame sync with 2 Playlist - advice

Postby azman » Wed Aug 12, 2020 4:27 am

Hi All,

I'm seeking any comments or experiences with syncing 2 playlist together (across a blended image) using Software Player licence system,
Hardware is a intel i9 with nvidia quadro - not concerned about hardware performance
Concerned about its accuracy in regards to sync with using playlists.

I have a requirement to link 2 playlist over a blended image, i.e Left playlist & Right Playlist
Playlist will be loaded from watchfolders.
Canvas pixel count exceeds 4k resolution limit on player licence, so need to create 2 split files.

Triggering playback control via WD,
DeviceSetParam(1,1,"Playback Transport", Play),DeviceSetParam(1,2,"Playback Transport", Play)
2 scripts - i.e. playlist LEFT on 1.1, Playlist Right on layer 1.2

Initial tests appear ok but....I'm cautious, having had issues with playlists (in earlier versions of PB)

If PB Player limit was based on bandwidth not pixel count would not have an issue
Canvas size - 7680 pixel on horizontal, whilst only using 800 pixels on vertical :cry:

Any info or comments would be appreicated
azman
 
Posts: 92
Joined: Tue Feb 02, 2010 11:43 pm

Re: Frame sync with 2 Playlist - advice

Postby Janina Baltaziewicz » Wed Sep 09, 2020 1:30 pm

Hi Azman,

As long as the two playlists really are identical and you keep them locked to time, they should remain in sync.
It could, though, be problematic if a Playlist did contain videos with different frame rates and frame rates different from the output frame rate, especially something like 30Hz vs. 29.97Hz.

For the trigger:
What you have should work, but with TCP you never know. If one of the packets containing a command was lost and it requires retransmission, the delay between the two arriving commands yould be noticeable.
Using UDP could help, but of course it's an unreliable protocol and if a packet is lost, it is lost.
My suggestion would be using the nowpointer to trigger the two Playlists in sync.
You can e.g. add a Cue on the first frame and use SeqGoToCue plus SeqSetState (play) to jump at the right place and just play.
Even here you could optimise reliability by jumping into the very frame and set up a short wait time, to give PB the time to load the files.

A completely different way to work around this problem would be to have content where the left and the right side of the image are not next to, but on top of each other.
You could then use Remapping to assign the correct positions later and wouldn't have to worry about the 4K limitation:
https://www.coolux.de/root/downloads/su ... _guide.htm

Cheers,
Janina
Janina Baltaziewicz
Customer Service Engineer
User avatar
Janina Baltaziewicz
 
Posts: 53
Joined: Tue Jun 14, 2016 2:08 pm


Return to Pandoras Box V6

Who is online

Users browsing this forum: No registered users and 18 guests

cron