How to achive a movie with 3d models like this one

Hi, for a university project i’ve got to create a a movie using what ever techniques i want.

I plan to use a mixture of techniques, mainly using a 3d model of my character in a pre recorded realtime enviroment.

like the raving rabbid adverts below

What i was wondering was is it possible to do this with blender. If so how?

Do i have to assign the movie of the real enviroment as a background or something else?

if i can’t do this in blender rendering, then could you please suggest a program that could help my plight ^^.

thx in advance

Yes you can, but you need a software for the 3D tracking, which will analyse your video and build the environment in 3D before exporting it to Blender. There are free softwares for that like Voodoo or Icarus.

Once you have tracked the shot, you export a camera and bring that into Blender. So to do those kinds of shot, you give up the ability to animate the camera. The camera is derived from the footage and the footage sits as a background plate some distance from the camera. All your 3D elements go in between the camera and the footage plane.