I use the Atem Mini Pro Iso for data acquisition (x2 Sony camera HDMI inputs) -> mapping via Millumin -> x2 Christie LWU 701i videoprojectors via HDMI. The purpose is to project the picture of a person talking live while she is talking on stage (theater show).
I tried the PiP effect but it doesn't change the delay.
I also use one feed without the Atem : the camera feed is processed through a simple data acquisition card (HDMI to USBC 60Hz video capture). The same delay problem occurs with this setup.
There's no delay when I use direct HDMI connexion between camera and VP.
My analysis is that somehow Millumin adds delay in my setup. However I've been told when I was trained for Millumin that the software was capable of processing live feeds without delay.
Could you tell me how I can solve this delay issue ?
Quick update on my delay experimentations. Hopefully this might help someone else.
With the tests below I observed that my usual delay is -7 frames = 280ms.
Here are the configs tested (I had an issue with my HDMI VP2 and had to replace it with RJ45 adapters)
The first one is my usual setup. (VP 1 on the left white screen and VP2 on the right white screen)
So I have : Reality O to> Sony A7SIII -3 frames to> Atem to> Millumin -5f to> VP1 -7f and to> VP2 -11f
In this second picture I bypassed the Atem with a small USBC acquisition card from Amazon.
Reality O to> Sony A7SIII -3 frames to> Millumin -7f to> VP1 -9 and to> VP2 -13f
Third attempt I tried bypassing the computer all together (no acquisition and no software).
Reality O to> Sony A7SIII -2/3 frames to> VP1 -4f
Same attempt but with RJ45 adapters :
Reality O to> Sony A7SIII -3 frames to> VP2 -11/12f
All of this is shot at 25fps. A friend of mine working on live music told me he experimented a small decrease of the delay when he shot in 50p instead of 25p. I might try it.
There are 3 things I didn't test : a different camera (I also use Sony FS5), the Atem Output and the acquisition without Millumin. So in the end I don't really know if Millumin is to be accountable for some of the delay or if it's just the acquisition part (which seems unavoidable).
Someone else suggested to use VDMX or OBS for the acquisition part and sending to Millumin via Syphon. I'm not sure adding another software in the mix would help. Also because I don't know how to use those softwares and syphon (yet). But would you recommend it ?
My conclusion so far is that I will have to deal with some amount of delay (big surprise 🤡). It seems ok up until -4 or -5 frames. I'll keep testing some of the things listed above and let you know if it's useful.
To solve our problem (someone on stage 'talking live' and her image delayed) we might end up delaying the mic output. However for the one scene without mic I don't know how to solve this yet.
It is normal to have a delay when you capture a feed on your computer. Usually, the latency of Blackmagic card is 3 to 4 frames, thus your results.
That's why in some situation, people prefer to mix the camera directly on the ATEM (picture in picture) with the rest of the content (managed by Millumin).
Of course, if you capture at 50fps, the duration of your frame will be lower, thus your latency in milliseconds. Also, you might ask Blackmagic support what is their best device to reduce latency : indeed, the ATEM is a switcher, not really a capture card, so maybe the result would be slightly better with an Ultrastudio Recorder 3G for example (we did not run benchmark between the ATEM Mini Pro and Ultrastudio Recorder 3G, so I cannot tell exactly).
For info, all softwares running Blackmagic devices are using the same library provided by Blackmagic. So differences should be quite small betwen them. Also, we did our best to optimize Blackmagic support in Millumin, and I doubt you would see a difference with other softwares. For sure, we do not recommend to add more softwares if your goal is to reduce the latency ...
I think you can put a delay on the sound within the atem (software) to lip sync. Every cam has it's own delay time when mixing the audio and video after the camera.
Comments
Hello @Wahbiahmed,
I guess you want to use the Atem to directly capture the camera, then mix it with the output from the computer, so you have minimal delay.
So you have to learn how to do "picture in picture" with your Atem. See this tutorial.
Best. Philippe
Hello, I have the same issue with my setup.
I use the Atem Mini Pro Iso for data acquisition (x2 Sony camera HDMI inputs) -> mapping via Millumin -> x2 Christie LWU 701i videoprojectors via HDMI. The purpose is to project the picture of a person talking live while she is talking on stage (theater show).
I tried the PiP effect but it doesn't change the delay.
I also use one feed without the Atem : the camera feed is processed through a simple data acquisition card (HDMI to USBC 60Hz video capture). The same delay problem occurs with this setup.
There's no delay when I use direct HDMI connexion between camera and VP.
My analysis is that somehow Millumin adds delay in my setup. However I've been told when I was trained for Millumin that the software was capable of processing live feeds without delay.
Could you tell me how I can solve this delay issue ?
Thank you in advance !
Hello @Axl,
What delay do you have ? 50-100 ms ? 1 second ?
Do you have a delay if you directly display the feed of the camera on the Atem Mini Pro ?
Best. Philippe
Hello Philippe,
Thank you for your quick answer ! Unfortunately I couldn’t make more tests before the Christmas break.
I will rebuild the setup in January and let you know.
Hello,
Quick update on my delay experimentations. Hopefully this might help someone else.
With the tests below I observed that my usual delay is -7 frames = 280ms.
Here are the configs tested (I had an issue with my HDMI VP2 and had to replace it with RJ45 adapters)
The first one is my usual setup. (VP 1 on the left white screen and VP2 on the right white screen)
So I have : Reality O to> Sony A7SIII -3 frames to> Atem to> Millumin -5f to> VP1 -7f and to> VP2 -11f
In this second picture I bypassed the Atem with a small USBC acquisition card from Amazon.
Reality O to> Sony A7SIII -3 frames to> Millumin -7f to> VP1 -9 and to> VP2 -13f
Third attempt I tried bypassing the computer all together (no acquisition and no software).
Reality O to> Sony A7SIII -2/3 frames to> VP1 -4f
Same attempt but with RJ45 adapters :
Reality O to> Sony A7SIII -3 frames to> VP2 -11/12f
All of this is shot at 25fps. A friend of mine working on live music told me he experimented a small decrease of the delay when he shot in 50p instead of 25p. I might try it.
There are 3 things I didn't test : a different camera (I also use Sony FS5), the Atem Output and the acquisition without Millumin. So in the end I don't really know if Millumin is to be accountable for some of the delay or if it's just the acquisition part (which seems unavoidable).
Someone else suggested to use VDMX or OBS for the acquisition part and sending to Millumin via Syphon. I'm not sure adding another software in the mix would help. Also because I don't know how to use those softwares and syphon (yet). But would you recommend it ?
My conclusion so far is that I will have to deal with some amount of delay (big surprise 🤡). It seems ok up until -4 or -5 frames. I'll keep testing some of the things listed above and let you know if it's useful.
To solve our problem (someone on stage 'talking live' and her image delayed) we might end up delaying the mic output. However for the one scene without mic I don't know how to solve this yet.
Hello @Axl,
Thank you for your feedback.
It is normal to have a delay when you capture a feed on your computer. Usually, the latency of Blackmagic card is 3 to 4 frames, thus your results.
That's why in some situation, people prefer to mix the camera directly on the ATEM (picture in picture) with the rest of the content (managed by Millumin).
Of course, if you capture at 50fps, the duration of your frame will be lower, thus your latency in milliseconds. Also, you might ask Blackmagic support what is their best device to reduce latency : indeed, the ATEM is a switcher, not really a capture card, so maybe the result would be slightly better with an Ultrastudio Recorder 3G for example (we did not run benchmark between the ATEM Mini Pro and Ultrastudio Recorder 3G, so I cannot tell exactly).
For info, all softwares running Blackmagic devices are using the same library provided by Blackmagic. So differences should be quite small betwen them. Also, we did our best to optimize Blackmagic support in Millumin, and I doubt you would see a difference with other softwares. For sure, we do not recommend to add more softwares if your goal is to reduce the latency ...
Best. Philippe
I think you can put a delay on the sound within the atem (software) to lip sync. Every cam has it's own delay time when mixing the audio and video after the camera.