Graphics

Sorry to revisit this topic (I think I did a bit over a year ago but I lost the notes) but I cannot solve this simple puzzle.
I want to use 2 video inputs to create a keyed element within Xpression.
I know it can be done, I have used it many times before but deleted the projects because I went in a different direction.

Video Input-1 has a video signal and video input-2 has it's key signal. i need to use those 2 materials mapped to a single quad to use as a keyable element within my scenes.

The magic sauce lives in understanding the relationships between material attributes such as "Previous Stage" and "Current stage" Alpha blending, etc.
Is it me that I cannot find practical usage examples of these attributes or is it that they don't exist?

Any guidance would be appreciated.


Thank you ROSS

In recent versions of XPression you can enable an option in the Input 2 settings of the hardware setup to indicate Input 2 is an alpha for Input 1. Then you can just use a normal live source material with Input 1 as normal and it will have the alpha automatically applied to it. This is much more efficient as the video/alpha are combined at the hardware level and it is impossible to have a frame drift between them.



#XPression

Thank you B. for that solution - it works quite efficiently but... I dont necessarily want my video inputs to always work as a key pair.
I could have several xpression scenes that use two distinct video feeds in NON PAIRED MODE.

I assume I require a script to enable and disable the hardware keying on a per scene basis?

Thank you again

#XPression