I have shots of people walking down a street, and I'm trying to track a graphic above peoples heads. Ideally, I'd like the graphics to bob as they walk, and twist in 3d space if someone moves their head or walks at an angle. I have Mocha and the default AE tracker at my disposal. Are either of these capable of achieving this? I have a decent grasp on how to track in 2d space, but as far as tracking the rotation and angle of a persons head position, and having the graphic acting accordingly, I have no idea. Or would it be more realistic of me to fudge the perspective animation manually?
Mocha and the AE tracker will give you 2d information. Depending on the shot you may be able to animate the scale and 3d rotation to fake a 3d move. Ideally a 3d tracker would be better suited for the job. Boujou or SynthEyes are a couple of the best- pricey though.