Vivian

If you want to do mocap on the cheap, put some visible, high contrast markers (half-polystyrene balls stuck on a black suit) on your target person, then film them with two cameras (one from in front, one lateral, as close to planar as possible and the same distance away from your world-zero). You also need to make a little tri-axis cartesian thingy, like three sticks at mutual right angles with poly balls on the end, that will act as your world-zero. Then hand-digitise using image-J (freeware, I'll dig out the plug-ins you need if you're interested) - literally click on the markers stuck on your joints and save the coordinates in each plane, then combine em into 3D. The more frames you digitise the higher res results you get, so if you only need guideline results you should be able to do it quite quickly. Seriously, I work in a biomechanics lab and its totally possible, we do similar stuff all the time - the results will suck, scientifically speaking, especially next to high-end solutions like qualisys or viacom, but they should be dandy as a basis for animations.