How to get marker data live-stream out of ARENA

zsero
Posts: 15
Joined: Thu Mar 03, 2011 5:05 pm

How to get marker data live-stream out of ARENA

Post by zsero »

Hello,

I am a Computer Science student and for my project I would like to use a OptiTrack system what my University has access to. What I would like to use it for is to get the real-time stream of 3DoF positions of about 6 markers.

My question is that although I understand that the best software for this purpose is the Tracking Tools, but my university has ARENA license so I have to use that one. The good thing is that I don't need any kind of rigid body information, I am perfectly happy with individual (x,y,z) coordinates for each marker. The most important part of the program would be the calibration, other then that I'm ok with a real-time stream of coordinates.

I would like to ask you that:
1. what would be the recommended way of getting out x,y,z coordinates of a real-time network stream coming from ARENA?
2. Do you have any C++ or Python sample program? (I mean a minimalistic, Can I use something like pyOSC to parse the network stream?

My other question is that how can I know if my University's version or ARENA is compatible with the 3-point calibration want? What is the oldest version what supports the 3-point calibration?
NaturalPoint - Mike
Posts: 1896
Joined: Tue Feb 01, 2011 8:41 am
Location: Corvallis, OR

Re: How to get marker data live-stream out of ARENA

Post by NaturalPoint - Mike »

With Arena, the best you could hope to get out of the system is rigid body information through the stream. There are some sample programs included that show how to extract data within the NatNet SDK installer, found here.
zsero
Posts: 15
Joined: Thu Mar 03, 2011 5:05 pm

Re: How to get marker data live-stream out of ARENA

Post by zsero »

[quote=NaturalPoint - Mike]With Arena, the best you could hope to get out of the system is rigid body information through the stream. There are some sample programs included that show how to extract data within the NatNet SDK installer, found here.[/quote]

Hi! In the meantime I've found out the NatNet SDK files and documentation and I've started looking at it. Do I understand it right that for experimenting I only need the ARENA USB dongle and some sample files? I mean that if I'm trying to develop a program what includes NatNet and I'd like to test it, I don't need to have the whole rig up and calibrated, but I can get the same results by playing back recorded tracks in ARENA? I mean just to generate the network stream.

By rigid body information, what do you mean? I can even specify like 4 points to be on one rigid object and then ARENA calculates the rotation, or I only get positions?
NaturalPoint - Mike
Posts: 1896
Joined: Tue Feb 01, 2011 8:41 am
Location: Corvallis, OR

Re: How to get marker data live-stream out of ARENA

Post by NaturalPoint - Mike »

You'll have to set the 4 points as a rigid body. They won't be able to move with relation to eachother when being tracked as a rigid body. You'll get the position and orientation of the centroid when using this for tracking.

Individual, Unlabeled marker position needs to go through Tracking Tools.

You should be able to extract the appropriate information from the NatNet stream with sample files and a USB dongle with a licensed version of arena.

Also, I forgot to mention: 3 marker calibration requires at minimum 1.6.0.
zsero
Posts: 15
Joined: Thu Mar 03, 2011 5:05 pm

Re: How to get marker data live-stream out of ARENA

Post by zsero »

OK, so do I understand right, that I cannot specify one point to be an individual "object" in ARENA? I mean, for example one finger to be tracked individually?

Or is it possible to make some kind of "dummy" deformable body just to get out the individual tracker information? I'm talking about cca. 6 trackers here, nothing more.

+ Feature request: a limited version or demo mode without license would be exteremely useful for cases like this. I mean for example ARENA would go to a mode where you could only play back files, not record or calibrate. But it would be perfect for
1. learning the interface,
2. developing 3rd party tools using NatNet,
3. experimenting/debugging broken scenes,
4. trying out new versions of the program prior to purchase
5. trying out how do different programs fit for different purposes, like ARENA user considering buying Tracking Tools, etc.

Since having access to the actual USB dongle in a multi-user environment isn't so easy, you could help learning and development around your system by implementing a demo mode.
NaturalPoint - Mike
Posts: 1896
Joined: Tue Feb 01, 2011 8:41 am
Location: Corvallis, OR

Re: How to get marker data live-stream out of ARENA

Post by NaturalPoint - Mike »

Deformable? No. The objects are rigid for identification purposes. Arena is the wrong software to use if you want individual deformable points. You'll need to use Tracking Tools.
zsero
Posts: 15
Joined: Thu Mar 03, 2011 5:05 pm

Re: How to get marker data live-stream out of ARENA

Post by zsero »

OK, deformable was just an idea. I want to track a single point, a fingertip of a user. Is it possible to do this in ARENA?
NaturalPoint - Mike
Posts: 1896
Joined: Tue Feb 01, 2011 8:41 am
Location: Corvallis, OR

Re: How to get marker data live-stream out of ARENA

Post by NaturalPoint - Mike »

No. You will need Tracking Tools to get the data for a single point.
zsero
Posts: 15
Joined: Thu Mar 03, 2011 5:05 pm

Re: How to get marker data live-stream out of ARENA

Post by zsero »

I've would have never thought that a $2000 software doesn't support the most simple function of a $800 one.

Even the big mammuth software companies always split their software in an inclusive way, and it's especially strange from hardware oriented company to limit higher-end software not to do basic functionality. I seriously don't understand since your market is clearly to sell more hardware, not to make your customers annoyed by forcing them to buy an other version too. Is it such a unique situation that someone wants to track a single finger after buying the $2000 high-end software?

I'd recommend your company to re-evaluate today's differentiation of your products as I believe it's not really the best one for your relationship with your customers.
NaturalPoint - Mike
Posts: 1896
Joined: Tue Feb 01, 2011 8:41 am
Location: Corvallis, OR

Re: How to get marker data live-stream out of ARENA

Post by NaturalPoint - Mike »

The issue is that Arena and Tracking Tools are both separate projects, not a different skin on the same project with features enabled or disabled based on licensing. The features, export methods, et. cetera are based on the needs of the particular product as it grew. Our upcoming version of Arena, however, will be based on a software merge with Tracking Tools and contain a number of the features that TT supports developed independently of Arena thusfar.

And, actually having looked back on it, you can get a single unlabeled marker out of Arena. You would need to use NatNet and stream with unlabeled markers checked. On the down side it would require some development to get the information via NatNet, however on the up side, it would be fairly independent of the version of either Arena or Tracking Tools moving forward.
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