Adding 3D object to Video Clip

Question

I have been a long time dabbler with Blender (back in the NaN days) but I've never really become proficient at it. Thus I am finding it difficult to do everything I need for this one project using tutorials. I am trying to:

1. Motion track a single point on a video - Done
2. Add a particle stream at an offset point to the motion tracked point - Done
3. Match the duration to a mouth movement. - Done
4. Render that all back out. - Fail

This fails because of my lack of knowledge. What I have tried:

1. render out with a background image of the video clip - fail, only get the particles with a black background.
2. Setup nodes with the movie and the render as inputs - fail, either only get the video, or the particles with a black background.

I have tried various iterations of this but I have never been able to get the video to render out.

Blend File

Any assistance would be appreciated.

Answer 1

Your problem is in the Compositor - you don't have your render layer hooked up to a Composite output node, in fact I didn't find any nodes when I switched on 'Use Nodes' so I rigged up a simple set up. Your scene didn't have enough light so I turned on AO, and I set your Shading tab to use alpha instead of render sky. I hooked the render layer alpha to the mix factor of the color mix node, and plugged the image node into the other color as a background(this is wher eyour video footage goes). The file should help a little to fix the original file hopefully. redone file