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Ex9 renderer in fullscreen mode with alpha in bgnd color?

Hey everyone.

I was wondering if the alpha info in the beckground color of a ex9 renderer is also included when it’s set to fullscreen?
What i’m thinking about: Taking the DVI signal of the video output where my v4 rendering is running in fullscreen into a video mixer and blend it like a layer with transparency over other content going into that mixer. So background in the rendering would be transparency in the video mix. Is that possible?

curious about your answers.

helo franz,

that is definitely not possible in one signal. you’d need a professional grade card like the nvidia quadro sdi series that (if i understand it right) can output a key/alpha signal side-by-side to the color output. not sure though if that would work out of the box with vvvv.

What videomixer are you talking about that would accept that?? I would suggest you check out Luma or Chroma keying, most mixers can do that.

Thanks for your answers!

The question came to my mind cause a friend did that before with a quartz comp.
As far as he can remember the setup was like this: The DVI signal from the rendering computer would go through a signal processor (like the imagePRO-HD from barco) into a mac on which the videomix was done with catalyst (http://samsc-pm.com/index.php?option=com_content&task=view&id=6&Itemid=28)

As joreg said that this is not possible in one signal it makes me wonder how they could have done that cause quartz does also output just one signal, right?

Maybe they replaced the background via lumakey in catalyst. Anyone familiar with that software?

the image pro had nothing to do with it, the quartz file can have a alpha BG, and was played in catalyst, a media server, as a layer over a video file, much like playing a video file with a patch rendering ontop of it in vvvv.
Just layers, no magic…

@cat: got that. but as the quartz comp was generated on a separate computer and transferred to the media server via DVI. Means the alpha channel would have to be transferred via dvi, too. Don’t think that’s possible.

thanks anyway guys. have to learn more about all those technical details…