Jump to content
Dataton Forum
Sean

Looping Videos Across Multiple Display Servers

Recommended Posts

Hello all,

I'll often use Watchout on tradeshows where we need to simply loop videos in sync across multiple display servers for hours.  Most of the loop techniques I've tried end up with poor results over time.

Things I've tried-

Simply settings videos to free running and looping - movies drift out of sync very quickly

Putting content into a composition and setting the comp to free run and loop - out of sync over time.

Creating a loop using a jump cue to hop back to the beginning of the video file - movie doesn't get preloaded so we get a frame of black

Two timelines with the same video that trigger each other to loop - inconsistent.  Sometimes it will loop fine, sometimes a frame of black will pop up.

Putting content into a comp, duplicating the comp over and over so it spans hours and playing it straight through -  inconsistent due to composition preload bug.

Copying whole timeline over and over and playing it straight through for hours-  only consistent approach I've found.

 

What do you usually do to simply loop a video without it going out of sync?

I have a show coming up where I'll use two Watchpax 4s to loop some video files for an LED wall. They must remain in sync all day.

Thanks!

Share this post


Link to post
Share on other sites
2 hours ago, Sean said:

 

Creating a loop using a jump cue to hop back to the beginning of the video file - movie doesn't get preloaded so we get a frame of black

 

I like to place a still a layer below the videos with a duration longer than the video I want to loop. In my experience it keeps that black frame from appearing with the jump. see attached example:

loop.png

Share this post


Link to post
Share on other sites

Free run and loop does exactly what it says. Free run means FREE RUN, i.e. WATCHOUT releases control over the file and does not care about keeping in sync anymore.

You can loop using cue points but you should make sure that the loop cue sits a few fractions of a second inside the video cue - before it get's unloaded from the graphic cards memory - and you jump back into the first frame, not before the first frame! It can be helpful to have the same frame twice at the beginning and the end of the video. 

Share this post


Link to post
Share on other sites

Ok, makes sense with the free run and loop.

I've been able to get the jump cue to work with low resolution files like 1920x1080, but not so much with multiple 4k HAP files. 

Why would you put the same frame twice in this case?  If the frame is not being decoded in time I'm unsure of how an identical frame would help improve the loop.

Thanks!

Share this post


Link to post
Share on other sites
29 minutes ago, Sean said:

Ok, makes sense with the free run and loop.

I've been able to get the jump cue to work with low resolution files like 1920x1080, but not so much with multiple 4k HAP files. 

Why would you put the same frame twice in this case?  If the frame is not being decoded in time I'm unsure of how an identical frame would help improve the loop.

Thanks!

If you jump out at the middle of a frame and back into the middle of a frame two halves of the runtime of the frame is lost. Therefore doubling the frame can help to prevent a visible effect in this case. If everything is rather slow you'll probably can do without this.

Share this post


Link to post
Share on other sites
4 hours ago, RBeddig said:

If you jump out at the middle of a frame and back into the middle of a frame two halves of the runtime of the frame is lost. Therefore doubling the frame can help to prevent a visible effect in this case. If everything is rather slow you'll probably can do without this.

Oh ok. Interesting. I'll give that a shot.

 

5 hours ago, SFluster said:

I like to place a still a layer below the videos with a duration longer than the video I want to loop. In my experience it keeps that black frame from appearing with the jump. see attached example:

loop.png

This is my go to approach if there's a static image on the front and back of the video clip as well. 

Share this post


Link to post
Share on other sites

This of course works as long as the underlying layer remains in the memory of the graphic card. I thought that you needed a much tighter loop, similar to what you get from free running and looping.

Share this post


Link to post
Share on other sites

Yea I do need a tight loop in this case, but I'm also looking for techniques for any type of loop.

My assumption of free-running and looping was that it begins to preload the first few frames ahead of time while it was nearing the end of the video.  Are you saying the first few frames remain in video memory the entire time the cue is active?    I'd assume that if the CPU was not always decoding previous frames jumping backwards in time would always be a lot smoother than it usually is.

I really wish that jump cues had a toggle to preload the video it's jumping to.  Though, a method of syncing free running and looping videos should be the priority, in my opinion.

It seems odd that we are using workarounds for such a basic feature.

Thanks again!

Share this post


Link to post
Share on other sites

I experienced the black „flash“ when looping an aux-timeline as well (as stated and whined about in several posts) There are two work arounds. One is the (mentioned before) underlying still for the moment of jumping to the beginning. BUT, I found it to only be working when that still is on the main-timeline. Which is a pain. 

And leads to the second, most reliable solution. I created timelines with the duration of the whole day and just repeated the content, instead of trying to loop, jump or anything automatic. Ridiculous, I know. But that is what I would do in your case.

Share this post


Link to post
Share on other sites
On 9/26/2019 at 3:12 AM, Sean said:

a method of syncing free running and looping videos should be the priority, in my opinion.

Contrary to what's said above, looping and/or free-running videos are synchronized across computers. Or, at least that was the case when I was involved. I doubt it has changed since. If looping or free-running video gets out of sync across computers, I would have considered that a bug.

Mike

Share this post


Link to post
Share on other sites

I have been working on a Watchout installation that as the same troubles described above.

System:

- New Rig with 6x 4k Outputs and 16gb Ram

- 6x 4k HAP movies with 30 secs.

 

When I first ran a show for testing the system it was just that one movie in free run and loop on the main timeline.

2 days later and the videos are completely out of sync...

 

method 2 = Second approach was doing the loop trigger by cues...

result 2 = black frame while looping.

 

method 3 = Third approach was one task running 3 instances of the 30 secs movies without free run and looping with cross fade between them and at the end triggering a second task to preload a copy of this task and to run it. Basically "cross fadding" between the two task with preloads ... #$%@@$% 

result 3 = terrible frame dropping between the cross fade of the 30 secs video....

 

Free Run and Looping was a basic function that I ALWAYS USED and never with this outcomes...

Did Watchout lost the simplest function of free running and looping a simple clip?

 

Any one with troubles running 6x videos at 4k?

What are the best approaches

 

thanks

 

 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...