Ghost Hunting with Kinect

Paranormal Activity 4

I don’t usually try to undersell the capabilities of the Kinect.  Being a Microsoft Kinect for Windows MVP, I actually tend to promote all the things that Kinect currently does and one day will do.  In fact, I have a pretty big vision of how Kinect, Kinect 2, Leap Motion, Intel’s Perceptual Computing camera and related gestural technologies will change the way we interact with our environment.

Having said that, let me just add that Kinect cannot find ghosts.  It might reveal bugs in the underlying Kinect software – but it cannot find ghosts.

Nevertheless, “experts” are apparently using Kinect sensors to reveal the presence of ghosts.  Here’s a clip from Travel Channel’s Ghost Adventures.  It’s an episode called Cripple Creek and you’ll want to skip ahead to about 3:50 (ht to friend Josh Blake for finding this).

The logic of this is based on some very sophisticated algorithms the Kinect uses to identify “skeletons” – or outlines of the human form.  The current Kinect can spot two skeletons at a time including up to 20 joints on each skeleton.  Additionally, it has a “seated mode” that allows it to identify partial skeletons from about the waist up – this tends to be a little more dodgy though.  All of this skeleton information is provided primarily to allow developers to create games that track the human body and, typically, animate an onscreen avatar that emulates the player’s movements.

The underlying theory behind using it for ghost hunting is that, since when someone passes in front of the Kinect sensor the Kinect will typically register a skeleton, it follows that if the Kinect registers a skeleton someone must have passed in front of it.


Unfortunately, this is not really the case.  There are lots of forum posts from developers asking how to work around peculiarities with the Kinect skeletons while anyone who has played a Kinect game on XBox has probably noticed that the sensor will occasionally provide false positives (which for gaming, is ultimately better than false negatives).  In fact, even my dog would sometimes register as a skeleton when he ran in front of me while I was playing. 

Perhaps you’ve also noticed that in an oddly shaped room, Kinect is prone to register false speech commands.  This happens to me especially when I’m trying to watch my favorite ghost hunting show on Netflix – probably because of the feedback from the television itself (which the Kinect tends to be very good at cancelling out if you take the trouble to configure it according to instructions – but I don’t).  I know this isn’t a ghost pausing my TV show, though, because the Kinect isn’t set up to hear anything I don’t hear.  Just because the Kinect emulates some human features – like following simple voice commands like “Play” and “Pause” – doesn’t mean it’s something from The Terminator, The Matrix or Minority Report.  It is no more psychic than I am and it doesn’t have super hearing.

Kinect 2 IR

Similarly, skeleton tracking on Kinect isn’t specially fitted to see invisible things.  It uses a combination of an infrared camera and a color camera to collect data which it interprets as a human structure.  But these cameras don’t see anything the human eye can’t see with the lights on.  Those light photons that are being collected by the sensors still have to bounce off of something visible, even if you can’t see the light beams themselves.  Perhaps part of the illusion is that, because we can’t see the infrared light being emitted and collected by the Kinect, people assume that what it detects also can’t be seen?

Here’s another episode of Ghost Adventures on location at the haunted Talumne Hospital.  It’s especially remarkable because the Kinect here is doing exactly what it is expected to do.  As the subject lifts himself off the bed, he separates his outline from the background and Kinect for Windows’ “seated mode” identifies his partial skeleton from approximately the waist up.  The intrepid ghost hunters then scream out “It was in your gut!”  Television gold.

Apparently the use of unfamiliar (and misunderstood) technology provides a veneer of seriousness to what these people do on their shows.  Another piece of weird technology all these shows use is something called EVP – electronic voice phenomena.  Here the idea is that you put out a tape recorder or digital recorder and let it run for a while – often with a white noise machine in the background.  Then you play it back later and you start hearing things you didn’t hear at the time.  The trick is that if you run these recordings through software intended to clean up audio in order to discover voices, they remarkably discover voices that you never heard but which must be the voice of ghosts.

I can’t help feeling, however, that it isn’t the world of extrasensory phenomena that is mysterious and baffling to us.  It’s all the crazy new technologies that appear every day that is truly supernatural and overwhelming.  Perhaps tying all of these frightening technologies to our traditional myths and collective superstitions is just a way of making sense of it all and normalizing it.