H264 Ringing Artefacts on ATEM Recording (ISOG2)

Hello,
I got client material here, 3 cameras from a greenscreen situation recorded with ATEM Mini Extreme ISO G2.

The material is well lighted and filmed so far. The recorded streams have the typical H264 noise and blocking artefacts (espacially in the red and blue channel - very noisy) but I can handle it with Neat.

Unfortunately the material shows also the H264 ringing artefact (aka halo or ghost). A thin but present dark black line around the object in the foreground - directly on its contour at the transition to the green background.

This artifact naturally makes green screen keying enormously challenging - to say it in warm words.

And yes I know, H264 is not the codec to choose if you want to key something out. What a client knows is not always the same, a compositing artist knows.

I would like to ask, is there a way to do recordings with the ATEM with other "non-gop" codecs, Prores, DNxHR or is this planed for the future? Or is there a way to further adjust the quality of the H264 recording?

I understand that Blackmagic wants this handy feature to record all incoming signals smooth and easily via USB-C and at one point there is an amount of data per second limitation. But it would be very nice to have the option, the possibilty to record with production-codecs if you want to. In this case, for example, with a reduced number of recorded cameras?

On the other hand I have to say, the overall quality of the H264 recording could be much better. The streams are recorded with 50Mbit/s, nevertheless the material is very noisy. And the usecase "Greenscreen" ist very typical for a studio situation, but also very typical to produce ringing artefacts during H264 compression. In my opinion, this could be reconsidered.

Well, any tips on what to try if the customer wants to stick with this recording method?
Personally, I would be in favor of recording directly into the cameras in this case anyway.

Thank you

Blackmagic Design take water to their ecosystem.
Atem iso with Blackmagic Design cam mean you can have every cam that record braw and an project for resolve to edit full resolution braw


Inviato dal mio iPhone utilizzando Tapatalk

The thing is, my client doesn't use blackmagic cameras. And according to the manual, if you use the ATEM with blackmagic cameras, you also can not record all cams in raw out of the ATEM.

The thing is, my client doesn't use blackmagic cameras. And according to the manual, if you use the ATEM with blackmagic cameras, you also can not record all cams in raw out of the ATEM.

the iso feature is that you have a h264 output, but record also a Resove project that edit all braw from Blackmagic Design cam, every cam record internally and later you relink to Resolve project.

Screenshot 2025-06-20 alle 11.10.01.png (30.11 KiB) Viewed 712 times

also my old pro, without resolve project i can enable internal recording of braw on my pockets.

but if your client not use Blackmagic Design cam, you cannot do that.

try to ask to your client to check and remove sharpening of camera, usually halo or ringing artefact are from in camera sharpening than compression, post sharp in camera not give them more high freq dectails, but give you headace for key later, eventually you can add later with neat video, which had a better and more controllable sharpening in post.
If you key with Resolve, in fusion tab, in the matte node there are some value to smooth and shrink grow edge that could help you to reduce halo, but it's better to avoid in the original shooting