how do i...

[substream]

change the background of a picture or a video?
As an example, I am going to record my kids with little poster boards with the letters of the alphabet. I would like to change the background to reflect a scene that goes with the letter. P would be a back ground with the Paris skyline in it.

Could i use a white background, or will it have to be blue? Will the posterboards and kids clothes have to be a different color than the background?

I'll be using Vegas for the editing. a Hi8 will record the takes.

[BJ_M]

look in your manual and the tutorials for "Chroma Key/"Green Screen" effect"