Live generates a string of midinotes with velocity 0 to 20 and back to 0. The velocity channel is used to tell the game engine which frame of the loop will be displayed. In this case, a loop of a growing flower is playing from frame 0 to 20 and back. So you can re-animate the flower by changing the velocities. Framerate can be changed by changing bpm in live. This technique also allows you to change in and out points of the loop live.