Adding an animated model into footage


I want to add an animated quadbot model to real life video footage.
What I did was checking “transparent” under the “Film” tab (Render properties). It looks like this renders only the model without any background which is what I want, but when I try to add the model to the footage through the node editor it renders with a black background and doesn’t show the footage. I also have a mask to mask out a car going through the footage so as if it appears in front of the model. What am I doing wrong if I want to make it look as if the model is in the footage ?





Use AlphaOver node to add robot over the BG. Then add car on top of that with either Mix (use mask in factor input) or inject mask to BG with SetAlpha and AlphaOver it on top of previous over. Working from back to front towards camera is usually the most logical way to set things up. Car does not create a hole inside robot, it covers the robot. Result is the same but logic is different.

Thanks, this solved it. To be 100% sure this is what you meant?


If you mask the windows at 50% grey, you’ll be able to see the robot through them :slight_smile:

Cool! Do I Make a new mask for that or just add new points in the existing mask?

I tried to remake this exercise with a textured quadbot however i ran into a small problem: the visual indicator for a keyframe for my mask dissappeared (for all keyed frames). Is there a way to enable them again or is this a bug ?



Open up a dope sheet in a window and set it to Mask. Then you can see all your keyframes and even move them around if you need to.