How to make AVI transparent...

Hi there

How can I make an AVI transparent?. Like I need to convert the background
color(say Red) of that AVI in to Transparent.

Ex.
I am doing AVI for file copying, similar what Explorer's got. Here I have
image of two folders and some moving objects. I want to make whole of its
background Transparent.

I am using TAnimate to this. But setting Animate's Transparent property to
TREU does not help me. We tried out making both Uncompressed and Microsoft
RLE AVI file formats.
We are using Delphi 3.1

TIA

RathnaRaj