SDI with Fill and Key
Fill and key gives you perfect transparent graphics on top of your video sources with hardware switchers like the Blackmagic Design Atem switchers range.
Grafias provide you with a View Output URL and you use this URL in the free OBS Studio software. You will need a dedicated laptop or computer with a Blackmagic Design Decklink card or the portable Blackmagic Ultrastudio HD. On this computer you need to install OBS Studio. The software will use grafias output url and gives you a fill and key to use in production.
Ultrastudio HD mini and Decklink Duo2 gives you fill and key from grafias
Paste the View Output URL overlay from grafias to a browser source in OBS Studio.