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Hacked Kinect is now a 3D video capture tool

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Re: Hacked Kinect is now a 3D video capture tool

#12
post #8
post #3

Earlier quoted context omitted.

The Kinect works by projecting an infra-red grid on to the room so you can't use 2 of them in the same space (unless you modify the hardware somehow)

Could you synchronize two Kinect devices on one clock and then toggle the display/capture of that grid every odd or even 10ms span? So, only one grid is displayed and processed during its 'slice' of time, with the grids strobing rather than continuously projected. Software-only, or would that result in too jerky of a motion capture?

10ms seems like a reasonably small period of time. I believe it is considered to be effectively instantaneous in UI.

Edit: Although, I suppose the "refresh rate" of the entire system would then be 20ms, which might be noticeable. Chop that down to 5ms per Kinect, and it might be viable.

Re: Hacked Kinect is now a 3D video capture tool

#14
post #7

Don't miss: a) His other video of the system where he shows that measurements of 3d objects exactly match real counterparts: http://www.youtube.com/watch?v=f1ieKe_ts0k b) His homepage of other experiments: http://idav.ucdavis.edu/~okreylos/index.html

Neat. I did something similar for my graduate thesis project a couple of years ago, but to play pool/billiards on the computer using real cue sticks (for practice and feel) http://mixedrealitybilliards.com

Re: Hacked Kinect is now a 3D video capture tool

#15
post #8

Earlier quoted context omitted.

Could you synchronize two Kinect devices on one clock and then toggle the display/capture of that grid every odd or even 10ms span? So, only one grid is displayed and processed during its 'slice' of time, with the grids strobing rather than continuously projected. Software-only, or would that result in too jerky of a motion capture?

10ms seems like a reasonably small period of time. I believe it is considered to be effectively instantaneous in UI. Edit: Although, I suppose the "refresh rate" of the entire system would then be 20ms, which might be noticeable. Chop that down to 5ms per Kinect, and it might be viable.

Only one "eye" [Kinect] has to notice/process the movement; the other can infer, during the integration step, that the "rest" of a moving object comes with it, rather than stretching out.

Re: Hacked Kinect is now a 3D video capture tool

#16
post #8
post #3

Earlier quoted context omitted.

The Kinect works by projecting an infra-red grid on to the room so you can't use 2 of them in the same space (unless you modify the hardware somehow)

Could you synchronize two Kinect devices on one clock and then toggle the display/capture of that grid every odd or even 10ms span? So, only one grid is displayed and processed during its 'slice' of time, with the grids strobing rather than continuously projected. Software-only, or would that result in too jerky of a motion capture?

Absolutely you can. That's exactly how LED matrix displays work (look up charlieplexing).

Unless the 3d environment is rapidly changing, you don't need that many frames per second from each device to capture a good image.

25 fps is one frame every 40ms.

Re: Hacked Kinect is now a 3D video capture tool

#18

I'm not in this space or planning on investing time into this but I just wanted to say Kudos to Microsoft for creating something that developers are excited about again... even if they didn't indent to do that. I'd start hacking on this if I wasn't invested in a different direction.

I wouldn't give MS too much credit. They bought the hardware from the company that created it.

Re: Hacked Kinect is now a 3D video capture tool

#19
post #11

Idea: Please, someone somehow need to attach via software a Kinnect and a 3D printer.

I have a 3d printer, but not a Kinect. Range data is not very good at all at creating 3d models. What you really want is that plus a turntable so you can get multiple views. To get a printable model, you need a mesh with no holes. A single range image has lots of holes, so you can't really print the image without filling them by taking multiple images and matching them. That said, I do think I'll make a 3d scanner based on this thing.

Re: Hacked Kinect is now a 3D video capture tool

#20

I'm not in this space or planning on investing time into this but I just wanted to say Kudos to Microsoft for creating something that developers are excited about again... even if they didn't indent to do that. I'd start hacking on this if I wasn't invested in a different direction.

Please keep in mind that the folks who did this did so while being threatened with prison by a cowardly anonymous Microsoft spokesperson.
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