video overlay for projection

[scrutor]

Hi,

I have a question about video editing and real time overlays, I'm planning to project a computer screen and videos for a concert on an auditorium's wall, since not everything is white there i would like to black out the parts where I have no white surface to project on. I have to project photos and possibly a visualizer on the walls. Is there a software that can do this or is there any other way that its possible?
on the picture below you can see my idea of how i want to make it work

thank you for your help in advance.

scrutor[/img]

[Bjs]

Sound's crazy to me ... the part about blanking out area's ?

Why not just make a screen you can hang up for the project ... and project all onto it .

An ordinary queen size white bed sheet on a lite pine frame would suffice as a temp solution .

As for the other , there is software capable of performing such function , but for "realtime" display function , the pc spec's would need to have serious grunt under the hood to pull this off .. and some of the product's are not cheap .

If you know what is being planned before hand , you may want to create the content prior ... it's less cpu intensive this way ... just like showing a dvd via the projector unit .

It's how I do it for the local group .

[mats.hogberg]

If you want to play a video, you could overlay a BMP with some AviSynth filter. So you'd play the AVS and project its output. Can't see how to do this for projecting "what's on screen" tho...

/Mats