Hi All,

I'm ready to tear some hair out......was hoping someone might be able to give me a pointer or two.

We've gor the latest iPi software, six SONY PS cameras, a fast PC/graphics with 12GB RAM......

When we set up, we're getting 640x480 video at 40fps. We've tried leaving the background brightness at normal, dark, and darkest. When the camera is reading the video back, it appears that at least 4 of the cameras are tracking the light used for calibration. We stop for 3-4 seconds at each corner on the floor while doing the floor and again when 'drawing' the verticle lines from the upper part of our box to the floor.

When the system is finished, (after about 20 minutes), we don't have a box and it looks like tow of the floor lines are not being displayed.

I've attached a diagram and photo of uor setup. Suggestions are certainly welcome, if you're in the Denver area, you're welcome to visit.....

Thanks.

First, from the mocap accuracy perspective, I recommend to set cameras at different height to get better coverage of the actor: not only from the side, but also from the top and near the feet.

Next, to have a better look of the problems you are experiencing with calibration, please provide one of your calibration videos.

I'll vary the height and if it still doesn't work, will provide a copy. Any suggestions as to which cams should be at what height?

Varying camera heights will barely improve your calibration. It just wanted to note that usually it helps for action tracking. I suggest having two cameras at higher height (2.5 - 3m), and one at lower height (about 1m). Two high cameras should not be neighbor or opposite. For example, 2 & 6 - higher, and 4 - lower.

Have you tried to disable "Auto detect initial camera positon"? With your setup, you can just reset camera positions with "Full Circle" standard pattern and start calibration.
What is your typical marker misdetection rate? You can see it in the "Scene" tab after the marker detection phase is completed. Click on "Camera X" buttons in toolbar to see value for corresponding camera. The values larger than 20% are considered bad.

Yes, we've tried disabling both auto sensing boxes. Not sure about the mis detection rate, we're going to try again later this morning and I'll note the rate.

Cheers

Hi,

Do your cameras appear in the right order in iPi Recorder? You can drag-and-drop them so that camera 1 appears in at first place, camera 2 at the second, etc... That's a mistake I have already made, and as far I can remember, calibration failed.

That floor is very shiny and reflective. I don't know if it's contributing to your calibration problem but in my personal experience, a shiny floor can confuse the tracker because it may see a double image and a lot of extra motion--this was especially a problem when identifying ground points.

In my opinion, you should avoid shiny reflective surfaces as much as possible, whether you use PS3 Eye or Kinect.

G.

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

Watch a one minute excerpt on Vimeo now!