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Point Cloud questions

Posted: Sun Jun 10, 2007 4:17 pm
by markdc
I just watched the new point cloud videos and they look great. My question is about the wand and the ground plane. Are these things that we will have to construct ourselves or will they be sold as an accessory? Also is there a maximum number of cameras? Thanks.

-Mark

Re: Point Cloud questions

Posted: Mon Jun 11, 2007 12:29 pm
by VincentG
I believe that we will be selling them, shortly, on the website.

Currently I think that the upper limit of cameras/system is 12.

Re: Point Cloud questions

Posted: Mon Jun 11, 2007 2:38 pm
by Jim
Mark:

We will be selling the calibration square on the site, and lots of different size markers as well.

You can make your own calibration square by arranging 3 markers in a 3,4,5 right triangle. The "4" is the Z axis and the lenghts can just be entered into the software. Default is 300mm, 400mm, 500mm.

The wand is just a single marker on a stick, we are going to let the customer handle this one!

Yes, about 12 cameras right now seems to be good. We are working to get this to be higher. 4 cameras per hub and 3 main root hubs on the PC is good. You could do 4 root hubs on most PCI cards, or our little Shuttle boxes we use, that could give you 16 cameras.

Re: Point Cloud questions

Posted: Tue Jun 12, 2007 1:48 pm
by markdc
Thanks. I'm anxiously waiting for the release

-Mark

Re: Point Cloud questions

Posted: Sat Jun 16, 2007 7:42 pm
by leith
What is the limiting factor at this point for number of cameras? CPU? Mem? USB bandwidth? PCI bandwidth?

If CPU, are the drivers multi-threaded? Will processor upgrades help?

If USB bandwidth, would a second USB card solve the issue?

If PCI bandwidth, anyone seen a PCI express usb card (snicker)?

If one were to use multiple overlapping volumes, would they be able to share a sync signal between the volumes, collect the data in parallel, and basically create an array?

Mind churning... waiting for point cloud software delivery...

Re: Point Cloud questions

Posted: Sun Jun 17, 2007 1:20 am
by beckdo
Even though we're doing lots of the heavy lifting on the cameras themselves, ultimately the CPU performance is the key player here. The 12 camera limit is a soft limit by the way. I believe with a high end machine you could take it on up to 16 currently.

I can't say enough good things about the new V100 camera. With the new V100 cameras you're going to find that you can capture a pretty serious capture volume even with a moderate number of cameras; And the tracking is sublime =)

Take a look at the raw data from the high-speed marker tracking demonstration:

Raw high-speed tacking marker data

And if you didn't notice, the Point Cloud SDK is available as we speak.

Re: Point Cloud questions

Posted: Mon Jun 18, 2007 2:59 pm
by seanboyette
Jim -
two questions -
what is the output format - is it just CSV?
and the format is col 1 -tracked point #, X, y ,z?
and
are you going to have any special for cameras/software?

Re: Point Cloud questions

Posted: Mon Jun 18, 2007 3:16 pm
by Birch
what is the output format - is it just CSV?
and the format is col 1 -tracked point #, X, y ,z?
Correct, the sample output from the Calibration Tool is in CSV format :

"The exported data is formatted with the first column indicating the number of markers, the second column with a timestamp, and then 3 additional columns (x,y,z) per marker."
are you going to have any special for cameras/software?
We aren't running any specials at the moment, but subscribing to the OptiTrack newsletter (from the front page of the site) is a good way to keep informed about any potential promotions.

Re: Point Cloud questions

Posted: Mon Jun 18, 2007 3:26 pm
by seanboyette
Thanks for the prompt reply -

so example of output is:

2,timestamp,X,Y,Z,X,Y,Z
1,timestamp,X,Y,Z
2,timestamp,X,Y,Z,X,Y,Z
3,timestamp,X,Y,Z,X,Y,Z,X,Y,Z

Re: Point Cloud questions

Posted: Mon Jun 18, 2007 4:35 pm
by sboyette
Would it look like this if the second one lost a point:

3,timestamp,X,Y,Z,X,Y,Z,X,Y,Z
2,timestamp,X,Y,Z,,,,X,Y,Z