Your Daily Kinect Hack: A Laser Sword

I like the little mirror at the bottom. Realitycam.

I’ve decided that I’m going to keep posting videos of Kinect hacks for as long as it takes Microsoft to publish a completely awesome game for their little motorised Eye of Sauron. I appreciate that this may be some time, but I’ve got a two litre carton of orange juice here. No danger.

Today, you can watch a man wielding a sword made entirely of light. It looks pretty cool, and even makes a sort of warbling noise.

The star of the above video, a Mr. Yankeyan, he says:

“Proof of concept of tracking and rendering a lightsaber in real time using a Kinect hooked up to a PC. Imagine the possibilities.

Best viewed in fullscreen 480p. I track a wooden stick and I overlay the light glow on the computer. Drivers using OpenKinect, image processing, tracking, and rendering using OpenCV. Audio recorded and processed using Audacity and played using libao.”


  1. Madjar says:

    What did he do with a kinect that can’t be done with a normal camera ?

    • Muzman says:

      Made it track on a lightsaber effect in real time ?

    • pupsikaso says:

      You could do it with any camera, but you’d still need the software. And that’s what OpenKinect is.

    • Wurzel says:

      What a normal camera couldn’t do is tracking how far away each object is, as well as taking an image. It results in a much smoother and more accurate overlay of lightsaber, as essentially the Kinect camera has depth perception.

    • BAReFOOt says:

      You wouldn’t need distance for rendering a light blade on the handle. A normal camera and a feature tracking library suffice. I know because I’ve done that.

    • HybridHalo says:

      You would need two tracking points on the object to calculate any rotation – the same information can be used to calculate the objects distance from camera too.

      I can’t work out precisely what’s going on here – I can see the object is tracked in real-time, but is this achieved by simply pixel tracking the video or is he making use of the kinects depth awareness and IR dots?

      The latter, can’t be done on any camera, of course. I thought that was the whole point of OpenKinect – to make use of the depth calculations Kinect does.

      p.s. I do this for a living.

  2. pupsikaso says:

    “Imagine the possibilities”?

    Oh I can see it now… smashed windows and screens, maimed pets, broken teeth. At the very least include a wrist strap with that thing!

    • Quintin Smith says:

      The Kinect swordfighting game of my imagination would definitely cast you as an ordinary (janitor, chef) who’s forced to pick up a sword in times of need. Hence no training.

    • squidlarkin says:

    • BAReFOOt says:

      A wrist strap? What, is your hand that weak??
      Have you ever seen a tennis racket? Or a baseball bat?
      Normal, healthy, people don’t need a wrist strap. They got working hands instead!

    • Joshua says:

      Depends on the quality of the grip.

    • pupsikaso says:

      People can’t hold a tiny wii-mote in their hands, and you expect them to hold a toilet plunger handle?

    • DrGonzo says:

      Tennis players and the like do occasionally drop or throw their bats/whatevers. But they don’t have a giant expensive TV right in front of them. However, Jedi never drop their lightsabers.

  3. Bornemannen says:

    This going to revolutionize the cybersex industry.

    Yes, that where my mind took me…

  4. plugmonkey says:

    Well, I had commented on this thread, but when I tried to edit it RPS decided it was spam and deleted it.

    I mean, it might not have been the single wittiest thing that has ever been written on this forum, but I didn’t think it was THAT bad…

  5. Tei says:

    I would feel better, if all these people doing hacks using the open source code driver, also release his hacks as open source. If only, because It would be easy to fake a hack with this, ..having the code prove the hack is real.

    I dont see any noticeable lag on this one…

  6. DevilSShadoW says:

    I love how Microsoft with all it’s money has literally no clue what to do with the Kinect. HINT: LIGHTSABERS YOU IDIOTS!

    • drewski says:

      Lucasarts has probably copyrighted lightsabres in videogames. Wait for Star Wars: Jedi Slicing.

    • bill says:

      That would only have worked 10 years ago before starwars jumped the shark totally.

    • Kandon Arc says:

      There was a tech demo at E3 of this very thing on the xbox. A Jedi cutting his way through stormtroopers on Naboo if I recall. It wasn’t an officially announced game though.

    • Phydaux says:

      Who needs another Star Wars game? Lets have a Star Crash game, you’ll still get to wiggle a laser sword.

    • Jhoosier says:

      There was a game out for the Wii that had “laser swords”. Can’t recall the title, though. Something-something-Hero. It was about some guy who decided he wanted to be an assassin and went the the pawn shop and bought a laser sword. Cool concept.

  7. clownst0pper says:

    Having used a Kinect many times, it really is terrible. The responsiveness is appalling.

    On a side note, considering almost all games involve you being stationary (as there is no physical method to manually navigate) the limitations on games is imense. It’s just a terrible product.

    • Nallen says:

      The first thing I thought when I watched that was jesus, laaaag

  8. bill says:

    A 2 liter carton of orange? what are you, american?

    • drewski says:

      As if an American would ever use “litre”.

    • Starky says:

      Reminds me of an old (bad) joke…

      What do Americans and cars have in common?
      They both measure their drinks by the gallon.

    • Jhoosier says:

      We do say “2 liters”. That’s the standard volume for the largest soft drink container. Beyond that, I don’t think there’s any other metric name used, even smaller soft drink bottles are all in ounces. Except for cocaine, that still comes in (kilo)grams according to police shows.

      Speaking of police shows and liters: link to (around 1:05)

  9. Garg says:

    The thing I noticed is that he moved the rod only ever incredibly slowly; is this because moving it any faster causes the slow response time to be an issue? Can’t imagine a lightsaber game that would have you gingerly moving your lightsaber around like it’s made of glass.

    • clownst0pper says:

      It’s because the tracking is so poor. Even moving it as slowly as he does, watch the mirror, it’s still seconds behind. It needs to be 1:1 responsiveness which it is a million miles from!

    • Headless Monkey Boy says:

      “Can’t imagine a lightsaber game that would have you gingerly moving your lightsaber around like it’s made of glass.”

      Maybe not a game, but its relaistic in a way. I mean you wouldn’t want to touch the operational end of the device. I think if i were to come accross a light sabre i’d barely move it for fear of severing my nose.

    • Trayder says:

      Watch the original trilogy again. Vader barely moves his lightsaber when he fights Obi-Wan. He just walks forward while holding the saber still at one point.

      Original trilogy lightsaber battles are quite in reach, pity they’re nowhere near as good as we remember them.

    • Ozzie says:

      But they’re full of emotions, a quality the battles of the new trilogy lack.

    • Josh W says:

      Nostalgic emotions? :P Honestly the only emotion I remember in the first film is the concentration of trying to fight someone. Yes the second and third ones mixed talky emotional bits in better, but the prequel fight scenes reflect personality in the styles of fighting far more effectively, closer to the style of a martial arts film than an old fashioned sword fight scene (where both use the same techniques, but one is more aggressive than the other). Personally I think that the weakness of the emotional content of the fightscenes is down to the general weakness of the script, which doesn’t match up to the choreography.

  10. rocketman71 says:

    Nice, but laggy. That’s Kinect, I guess.

  11. indirectx says:


  12. noobnob says:

    A Kinect game can’t be any more awesome than this.

    • Soundofvictory says:


      …hahahahaha. I love the look of absolute apathy on the guy’s face too.

      In Soviet Russia Kinect plays you!

    • Tei says:

      Stating the obvious: after the video of the dude finishing a level of COD withouth shotting, heres a dude finishing a race withouth moving.

  13. Muzman says:

    Fuck all this game crap. When can we sort documents Minority Report style? That’s the future baby.
    (In a few years it won’t be super cool cops who can see the future though. It’ll be sweatshops filled with people sorting mail, ok-ing bank transactions, doing audits etc. Whatever’s left you still need human accounability for.)

    Seriously, I can’t really see the appeal of this sort of thing. It’s very clever (I’ve worked with older head and eye tracking systems in behavometric analyses and, at the time, actual tracking was pretty optional). But force feedback is surely what people want for proper racing games.
    Some combination would be better. It might be fun with a CoD type thing where you move a character with a controller but can look around corners etc with your own head. That sounds cool, in theory.

  14. Juror #9 says:

    FASTER FASTER (as someone else said above.)

  15. Sagan says:

    The main thing is, that Microsoft spent ginormous amounts of money on the body tracking AI. And it will be very hard for the open source developers to mimick that. Meaning that they won’t ever be able to reliably track your body. (and all the quick first tries are going to be glitchy and frustrating to use) So we shall see how far they can takes this, but I’d guess not much further.

    • Muzman says:

      First thing: I know sod all about the system of course, but I’d have thought this all was in hardware (or the Kinect hardware). If not this guy wrote in tracking software himself onto just the camera feeds? I’m impressed (real programmers may be less so).
      Second; It may not be that big a deal, since I doubt they’re trying to recreate the games system. What they’ve got means a cheapish off the shelf multipoint tracker with depth for use with all kinds of stuff. Unless you think there’s no way it’ll be able to just do, say, hands while you’re sitting down without all the skeletal prediction etc. Which might be fair enough. (I just recently looked up the specs and the cameras seem tiny and slow, so the tracking behind the full system is pretty remarkable, but it also explains the lag and response problems etc)

    • Tei says:

      “The main thing is, that Microsoft spent ginormous amounts of money on the body tracking AI. “

      Executives and lawyers have a huge salary.
      I think theres a lot of tools and code already about artificial vision. Artificial vision programs is what you do when you don’t know what to do, and people use to love the tools that make AV cheapist, like mathlab.
      The basic science is probably routine.

  16. foomanchu says:

    As awesome as this is, can’t someone hack it so I can use it as a webcam in Skype.

    I’d like to buy this but I need something so I can justify a purchase

  17. Catastrophe says:

    He should of added some effects to when he placed it on the chair he caught his arm and his arm fell off, then the saber sliced straight through the chair.

  18. Melf_Himself says:

    This guy does it better: