I have posted “Multitouch fever” where has a link from sport4minus.de who was producing multiouch table and open out the whole progress. Today we can see a very fine-developed final product loopArenaMTC which is Jens wunderling, the webmaster, crewed with MTC.

The interface is programmed in Processing 0091 using the proMidi Library. But it seems to me that the version in the video is kind of openSoundControl (from the page). And it mentioned it is using libavg, a graphic library, do the tracking.

Extended Reading:
touchLib (which TUIO is developed under this library, and it seems be developed with OpenCV: http://www.whitenoiseaudio.com/touchlib/
ReactTable: http://mtg.upf.edu/reactable/
NUIgroup: http://nuigroup.com
More Videos on Multitouch in nuigroup: http://nuigroup.com/log/comments/video_updates/
TouchTracer: http://nuigroup.com/forums/viewthread/268/