

Two Kinects at once is now possible - kristofferR
http://kinecthacks.net/two-kinects-at-once/

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kristofferR
I'm sorry if you can't access the site, it's getting slammed right now. I'm
getting more memory soon, if you can't access it today you should check it out
tomorrow.

The video is here: <http://www.youtube.com/watch?v=5-w7UXCAUJE>

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kristofferR
Memory has been updated now :)

BTW, does anybody know why I can't edit my comment?

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sorbus
You can edit comments for an hour after they're posted, but not later.

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X-Istence
What if one were to strobe the IR for each of Kinects and only have the
camera's do the frame grab for depth when that Kinects IR is on?

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gojomo
That was my thought as well. Or, perhaps with added filters on the projector
or IR camera, using slightly different wavelengths of light from the different
sources.

Or, perhaps assuming a future more capable projector(?), interactively refrain
from drawing dots in already-covered areas.

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nitrogen
I'm glad to know that I'm not the only one who thought of these same ideas. I
suppose one reason I'm glad is because it reinforces my current belief that
too many patents are being granted on ideas that all of us would have created
given the same information.

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waterlesscloud
Willow Garage is working on multi-kinects as part of ROS (robot operating
system).

<http://www.youtube.com/watch?v=rYUFu64VXkg>

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paul9290
I didnt grasp the point of two kinects in the room and have it display on the
TV? Can anyone explain the point?

What I thought was hey with two kinects that cover my movement in say my
bedroom I could motion or snap to turn lights on and off(or even dim lights)
and other electrical appliances/entertainment from comfort of my
recliner/couch/seat, etc. Maybe that's what he was going for here?

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throw_away
with two cameras, he's able to make a better 3d model of the room. if you look
at the examples using just one device, it looks more like a popup book - plane
cutouts in front of other, occluded planes. still, even with two in this
orientation, he can't see the backs of what he's looking at. I wonder what the
minimal number and best orientation would be to get a believable 3d map of
everything.

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spc476
Four would be optimal (think four sided die---each vertex would be the
location of a Kinect) but I think three would work for most situations.

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ABrandt
Does anyone know why the image significantly smooths out at 2:08 in the video.
It seems to be caused by the speakers shadow, but I'm not sure why that would
happen.

Great work too, by the way. I'm astonished by how far the boundaries of this
hardware have been pushed in a matter of weeks.

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elblanco
Kinects project an IR field of dots that they use to measure their
surroundings -- these fields can interfere with one another if there are two
Kinects in the room. He likely just blocked the field from one Kinect while we
were viewing the capture from the other one thus enabling the Kinect to
perceive it's "own" field correctly.

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icegreentea
Anyone know how the calibration works? I honestly cannot think of a way the
checkerboard would help eliminate interference.

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kj12345
I think it's to calculate where the cameras are in the room. If you know where
the four corners of the board are in each view you can figure out the position
of each camera, and then the two views can be merged properly.

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joeyo
It's not only to calculate the position of the cameras (x,y,z) but also the
additional DoF of the lens orientation (roll,pitch,yaw). Any set of eight
points would work, but a checkerboard provides a nice surface with a known
geometry. The checkerboard is also handy for correcting lens aberration.

Here is the standard algorithm: <http://en.wikipedia.org/wiki/Eight-
point_algorithm>

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recoiledsnake
Won't the IR spots from one Kinect interfere from the ones from the others?

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slashcom
That was the worry and it is indeed the case. However, as demonstrated in the
video, the interference wasn't as bad as expected.

