http://web.mit.edu/newsoffice/2010/pulse-camera-1004.html MIT did it a few years ago, a few different ways.

Here is a good read for you:

http://people.csail.mit.edu/mrub/vidmag/

Watch this demo from 7:53 on. It will show heart rate.

They say they are also using the colour camera. That could prove to be a potential problem.

http://gizmodo.com/kinect-2-full-video-walkthrough-the-xbox-sees-you-like-509155673

Yes!  And oh dear, when people play naked Kinect - the infrared reveals!

I wonder why they have the infrared out?  For some future accessory?

it measures the pulsations in the neck. How accurately, I don't know. However, they appear to be taking two different measurements in order to determine the pulse.

The method for doing this is describe in a recent patent awarded to Microsoft as well.

Basically an image is taken, then the differentiation of that image against the previous one is determined. This is then done about 100 times per second.

we'll see i remain skeptical about it, taking pictures 100 times per second may not be necessary, because if u think about it, human "normal" heart rate is about 60-100 times per minute. So if you have HR of 60 beats per minute, u just have to measure difference within that 1 second. So one picture each 500ms will do the job. But as you become more tachycardic, then of course measurement needs to be more frequent.

I do not see this working on ALL people, what about patients whom are on beta blockers that slows HR down artificially. And what about patient that I have pacemaker with set rate? u know, I will see once i get my hands on it. But anyways, I don't see it as a "game changer" anyways, myself.

I don't think it's a game changer, I think it is an attestment to the fidelity of Kinect 2 more so than anything. 

Yah i agreed with you. It is interesting from technology perspective, and I am just thinking about its use in the hospital, probably overkill though. I mean HR is something i can measure easily with my hand on the patient's wrist with my watch, but it's certainly nice if it can measure it.

I was just thinking about patients with atrial fibrillation, irregular arrhythmia, how that will work, it will confuse the shit out of the Kinect because there is no pattern to A-Fib, ur heart rhythm and heart rate is irregularly irregular.

Tell me again, how does the 1080p 30Hz rgb camera take pictures 100 times a second?

I am simply replying to a previous message, if u have two cameras, each with 60hz u can get close to that, but again, it's not necessary if u r tracking pulse on a human being, we are not freaking humming birds lol, we beat 60-100 RESTING, exercise ur target heart rate is 220-age x 85% so....yah don't need to do a 100 pic per second