Resolume Forum

Hi,

I have a 30 fps composition, with 30 fps DXV clips, no alpha, outputting to a 60 Hz screen, 30 fps SMPTE coming in through a Focusrite Scarlett interface, 30 fps SMPTE set in preferences.

When playing the clips in Timeline mode, everything works great. Unfortunately, I need to use SMPTE, and that's where my problems start.

1. Offset calculation

For instance, I set the SMPTE start offset to 00:00:00.27. When I trigger a different clip and go back to my previous one the offset now reads 00:00:00.22 - even though I have not changed anything. Interestingly, when I click the + button it changes from 22 to 28, so it's like it remembers that it's really 27, just displays it incorrectly. It also seems to work OK, so it's not that big of an issue.

However, when I restart Resolume, things go sideways. It still claims that the offset is 00:00:00.22, but now when I click + it goes 23,24, and... 00:00:01.00. So somehow, it treats the video as 25 fps offset-wise, and it's not possible to set the offset to 26th-29th frame. The first 25 frames are still correctly timed in the 30 fps video, so if I need an offset smaller than 25th frame - everything works great. The only way to fix this is to reimport the video.

Whenever I need an offset in the range of 25-29th frame I just set the in point of the video to 0.15 (fortunately, I can do that as the videos are not looped), and than recalculate the offset. So instead of 00:00:00.27 (which would be interpreted as 00:00:01.02) I set the in point to 0.15 and then the trigger to 00:00:01.12 - it's a quick hack, but it does the job, everything plays in sync.

This tells me that there is something wrong "under the hood" regarding SMPTE frame rates, and my second problem seems to confirm that.

2. SMPTE playback smoothness

When playing a 30 fps clip locked to a 30 fps SMPTE I can see some stuttering, a couple frames dropped every second, pretty much like it was playing it as a 25 fps video. SMPTE is properly received as 30 fps, and the "clip time" counter also "goes through" all 30 fps - there are no obvious dropped frames here. Sometimes, after many restarts, copying, pasting the clip etc I can get the playback to be ultra-smooth, just like it should be, so it definitely is possible But then, when I copy the clip, and paste it onto a new layer, with the same settings - it stutters again. I can even mix between layers with same settings, same clips, same SMPTE signal, and on one layer where the clip "magically" started working it works OK, on the other one - it doesn't.

Am I missing something here? Is there any other place where 25 fps can be set, causing all this trouble and confusion?

Thank you for your help!

Thank you for letting us know.

We're working on #1.
But even though the displays are not showing the correct offset values, the playback was stable and accurate in out tests.

#2.
Try setting your composition to Auto FPS.
(Assuming you have SMPTE fps set up properly any where and you are not using a drop frame TC.)

The Composition Rendering is not synced to the SMPTE, and the display refresh rate is not synced to the Composition rendering, so there are at least 2 stages in the render chain where the frames would have to match perfectly, so you don't see jitter.
Composition Auto FPS would give you a better chance for the clip and composition frames to match up.
I hope this explains what happens.

Hi,

Thank you for your insight!

Unfortunately, with the composition set to auto-fps I'm still getting mixed results. Once a particular clip starts playing properly then it's very stable and problem free. Some clips work right out of the box, some require numerous restarts and reimports, and I still can't get some to play smoothly.

Once the playback starts, if I change the playback mode to timeline then it continues smoothly, but I loose timecode chasing - it works more like a trigger to start the clip. I've been searching for a workaround until I can isolate the cause of this problems. Is there a way to map the transport mode to a midi controller? That way I could start with SMPTE, change to Timeline, and then when required briefly change back to SMPTE and to Timeline again - that'd give me a sort of a "jump to current timecode" feature, which will be sufficient for my current needs.

Still, having the clips render smoothly off SMPTE would be the best solution

adrianmik wrote: Wed Jun 20, 2018 13:14 Is there a way to map the transport mode to a midi controller?

Yes, you can map the Transport type to Midi.

Some clips work right out of the box, some require numerous restarts and reimports, and I still can't get some to play smoothly.

Are you sure these clips are DXV?

1. That's great, this will definitely make my setup perfectly usable in most cases

2. Yes, I am sure, that's what Resolume tells me too - when I used ProRes Proxy I had terrible choppiness in SMPTE mode, so no mistakes here for sure! After numerous trials and errors I've been able to get all of my clips to play properly, and now it's 100% repeatable. Still, I have no idea why some would "just work", and others would cause me so much trouble. They were all batch-converted from ProRes 422 Proxy to DXV (Normal Quality, No Alpha) using Compressor.

So it seems that my transition from Qlab to Resolume has been successful after all
I hope that everything will go well during my shows this weekend!

Thank you for your prompt help and support, even though the original cause of these problems still seems unidentified.

Hello,
just from my side (after 20 years of touring business as video director):
Timecode is a non-constant, analog and very "slow"signal...as we know.
So even on all the other systems, like pandoras box, catalyst ect. ,it will not work to see smooth clips, when you trigger ever frame new. If a TC "frame" start up only one millisecond to late, the rendere have to drop the next frame to be in time, cause the framelenght/time is fixed.

So using the TC just as a trigger is very common.
I use resolume exact the same way as you guys explained it.
Its not that handy, but it works.
I still hope that sometimes there will an option more in the timeline dropdown, called "Start TC" or so...

all best
flow