I'm having trouble with the calibration step. I've followed the directions but I'm getting a lot of yellow in either of the Kinects when I'm rotating with the board. The Kinect which is facing the boards gets good data but as I turn the board towards the second Kinect, the first one starts getting more and more yellow points. It looks like this is due to the interference (when I block either one of the Kinects, the other sees the board perfectly well -- no yellow at all regardless of the angle).
During the calibration in iPi Studio the green dots that are supposed to mark the edges of the plane end up all over the place, in the middle of the board most of the time -- because there's just a big hole in the middle of the board most of the time.
I've used different materials for the board: white foamcord, thick cardboard and something like a particle board, with the same results. I've tried offseting the Kinects so that one is pointing slightly up and the other one slightly down, without much improvement.
How did you avoid this problem? Are your Kinects at exactly the same horizontal level? In my setup the Kinects are about 3 meters apart and the distance to the actor from each Kinect is about 2.5 meters.
Any suggestions on troubleshooting?

I get yellow along the far edge if I rotate the board too far; I think this is normal. You should try to avoid getting too much yellow so don't over-rotate the board. A little yellow is okay though so long as enough of the plane can be recognized with adequate depth by the software to define the angle of the plane.

The green dots, by the way, do no mark the edge of the plane, they just define the angle of the plane relative to the camera. In other words, if your calibration is good, all you should ever see in each frame is three green dots some where on the surface of the board--just as you described. :)

In Studio, how does your camera positions look after you bring the scene calibration data into a motion tracking project? Just curious because what you describe so far doesn't sound unusual in my experience and I'm getting perfect calibration results.

For best results, make sure you're taking advantage of the Kinect's full depth range. Red is foreground and blue is background. The middle range is colored green, so ideally calibration should occur in the middle of that area. You should see all three colors (plus black for 'distant' background and yellow for 'unknow'). If all you see is mostly one or two colors in your video, you may need to push the cameras back or shoot in a bigger room. When you do your actual motion performances, you should make your T-Pose in the middle of the green area. (You can see the videos I recorded last week to see what this should look like--the links were posted earlier in this thread, or you can just visit my blog.)

Hope this helps.

G.

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!

can you add a dual kinects demo that has several turns?

Suer, Do you mean several Body Turns, Or Camera Turns?

I just want to be sure of your request.

Thanks



can you add a dual kinects demo that has several turns?[/quote]

@mrbones i mean body turn. with one kinect, my problem is that; on body turn kinect cannot see one arm.then it lose reference and the rest calculation is wrong. i have to correct the pose at a specific frame. i have to watch all calculation period and pause it, correct pose and go on forward tracking.

I am very happy with two Kinect cameras. In the example below, of a man turning 90 degrees to kneel, with only one camera I would have occlusion problems with the right hand and the right knee; they would fly all over the place. No such problems with two Kinect cameras. The trick is to calibrate the two cameras carefully beforehand, and it's not hard to do.

http://youtu.be/tPLrV2PH2YM

Hey guys,

Here is one test with a single kinect:
http://kim.shade.ca/temp/xnlSTA_singleK ... Jump01.avi

I just got a second one and am attempting to calibrate. As was mentioned by another user, it does seem like the kinect rays are interfering with one another. To avoid this, I put a furry blanket over my calibration board and it reduced the missing (yellow) depth data.

However, when I look at the overlap of my two depth maps, my T pose is off, as if calibration had failed. I wish I could adjust the calibration by moving my cameras around with translate/rotate tools. Either that or more control over the tracking of the board.. maybe something similar to character tracking, except for board tracking. Something to refit the pose of the calibration board.

Otherwise great job iPiSoft guys, so far so good!

-Kim

UPDATE: I just noticed you actually can translate/rotate the cameras around to adjust scene calibration! Awesome!
UPDATE: I found that it is important to rotate the calibration plane about a precise axis. Otherwise there will be an offset in the two depth clouds.
WARNING: Always turn off the power on your kinect when you are done recording. Last week I left my computer running during the night while it was tracking my animation, also leaving my single kinect connected to my usb port and powered on. When I came back the next morning, smoke was coming out of my computer. My power supply had surged, destroying all of my three hard drives. It might be a coincidence, but watch out!

I posted this info the other day in the Gallery section but forgot to mention it here: the 'preview' version of Happy Box premiered on Gothtober last Saturday. The announcement thread is here:

'Happy Box' preview is live at Gothtober!

To see the short, just go to gothtober.com and click on the 29th.

I want to point out that this is a 'preview' version of Happy Box as I had to cut a lot of corners to make the deadline for Gothtober. The final version will have lip sync animation, a few bug fixes and improvements, and a tighter edit. It will come out later this month, and a full HD release should follow in December. In the meantime, please enjoy this version for what it is. :)

The final version of Happy Box will appear at [urlhttp://www.littlegreendog.com]www.littlegreendog.com[/url]. I'll be sure to make that announcement when it's ready.

G.

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!