ATEM Television Studio Chromakey

Hello Everyone,

We are using the chromakey/green screen functionalities of the ATEM, and it seems very powerful when using a graphic from the switcher itself - our problem is that we need to be able to retrieve the transparent video (e.g. with the alpha channel) from the HDMI out, so we can use it directly in in a software we're developing.

So the big question is can we rely on the chromakey system of the ATEM and get the alpha video from the output so we can manage the composing on our side?

Thanks in advance

I don't think it's possible to output a video with alphachannel from atem.

As I know (which may be wrong), SDI and HDMI doesn't support any alphachannel.

But you may have a look at such sdi cards with internal keyer as the Decklink 3D extrem HD.
It has a built in keyer which you may be able to use along with decklink sdk.

If you could give some more info about what exactly you want to do, we maybe find a good solution.

cheers
sublan

Dual Link and 3G-SDI both support alpha channel in certain modes. However, the ATEM switcher does not support that output. I actually don't know of much gear that does. It is kinda a wonky part of the spec (that is a technical term).

Thanks for your replies!
And yes you're right it seems that if we want to use the Switcher for chromakey then we need to do everything on the switcher itself - as we're developing a software where the user can select there own background it seems that the best option is to look into the ATEM SDK

Or, as i suggested, you have a look at decklink cards with internal keying options like the HD extrem 3D and using it's decklink sdk.

This would be the better way, because there would be no need to send the chosen bg images over ethernet to ATEM which may lack in performance, especially when using it as live feature and not only as a setting.

cheers
sublan