What software is used for this?

Hi,

As a newby to creating animations (I´m a theatre maker) I have a question I hope you can help me with:

for a new project we would like to create an animated projection on the background horizon canvas as part of the decor (a sort of "living collage" to illustrate the theme of the scene). A bit like this: http://vimeo.com/13844867

Can anyone point me in the direction of what software is being used to create this? Or in other words: I would like to be able to isolate characters/figures/stuff from pictures (PNG?), cut them up and make them come alive. I also read something about creating a bone structure to make them move more easily?

Any tips are much appreciated!

Kind regards,

Charles