Clean Background removal with blob detection

Yes, am a little ahead in the background removal. I have now removed the background noise that escaped from my first layer background removal algorithm. I've added a second layer of background removal that removes smaller moving particles without hassle. Now the blob detection is more meaningful. I am also working on an advanced blob detection to solve some problem I am facing with the current one.

Am also wondering how I can detect overlapping blobs that lie in the same distance from the Kinect. Ofcourse, its easy to separate blobs that are at different distances, but when 2 users shake their hands, I am wondering if I can detect them as different blobs.