"Bluescreeneffects" without blue Background

i’m totally new to vvvv and i’m not sure if its the right application for what i like to do. So i hope you can help me!

I like to do the following:
Put a Camera (Video or Webcam) in a room. Then “calibrate” the still Image of the empty room. Now whenever somebody is going in this room, you can press a button and the camera is taking a picture. I think there is no problem with this ;)
Now comes the hard part: I Like to cut everything out in the taken picture which wasn’t there wenn the Camera was Calibrated! So for example: if one person is going to the room an take a picture, i like to have only a picture from the person, so i can change the background of the picture (the room) to what ever i want! Normaly i would take the picture in front of an blue wall, but i like do do it in a normal room!

I hope you understand what i mean…

Is this possible with vvvv!? Any hints or examples how this can be done?

Thanks for your Help!!

Is this possible with vvvv!?


Any hints or examples how this can be done?

have a look at these pages
pixelshader for newbies
difference between 2 textures


once needed something similar…

so here the shader i used. with option, to just show the alphachannel and adjusting its contrast.


bg_suppress.fx (3.8 kB)