SDI output with key and fill signals

Hi there.

The only post about this topic I could find here is 2 years old so I figured I should ask again.

Does anyone knows about outputing key and fill to discrete SDI outputs on blackmagic/aja cards like those Decklink Duo2 Mini?

I think it is completely possible to route only the alpha channel from a video clip or some 3d render independently to a separate output and use them with broadcast systems to overlay my project on top of an IMAG signal.

Does anyone have experience with this method?

Thanks a lot any input is appreciated!

tomalley I use the notchblock inside disguise, the. it’s absolutely no problem to separate the key and fill ; as the output is RGBA. In a standalone version I imagine having two outputs with two image2d, one extracting the RGB value of a image2d and one the key… somehow … make sure you uncheck output premultiplied alpha