The OP used 123D Catch which uses a point cloud to generate a polygonal model ;-) I think in catch you can select non-connected bodies, maybe a laso sort of tool to delete background noise. I made a video today using blender to clean a Skanect model, which would be tools similar to what you'd need to do to a Catch model.
Note: I need to record sound for the video, and then a video wizard needs to make it pretty before it'll be public.
Last edited: May 12, 2016