VRPN and Processing developing environment

Working with OpenViBE signal processing scenarios and doing scenario/BCI design
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Peegee10
Posts: 2
Joined: Mon Oct 15, 2012 9:54 am

VRPN and Processing developing environment

Post by Peegee10 »

Hello everyone!

I would like to create a simple SSVEP Speller based on the OpenVibe SSVEP scenario. In the past I often used Processing as developing environment, because you quickly get some useful results, and I would like to use it again.

Unfortunately I haven't been able to find a VRPN library for Processing so far. Does anyone have an idea, how to include VRPN into Processing?

I'd welcome any help.

fabien.lotte
Posts: 112
Joined: Sun Mar 14, 2010 12:58 pm

Re: VRPN and Processing developing environment

Post by fabien.lotte »

Hi Peegee10,

We have actually done something similar with colleagues. We have connected OpenViBE and Processing via VRPN using Java (not for SSVEP but for motor imagery or P300 though, but the approach is exactly the same). To do so you have to use Java, since there is a VRPN library for java (which comes with the C++ VRPN library in the official package). We used Eclipse to do so which was rather convenient. In Eclipse you add the Processing packages so that you can call processing functions from your Java code, which Java code will be implementing the VRPN client. I have attached two java files doing that (one is the VRPN client, the other one uses this VRPN client and calls Processing functions) to give you an example. The main drawback of this solution is that you have to be able to code in Java. However, I don't know any solution to directly use VRPN in Processing.

I hope this helps,

Best regards,
Fabien
Attachments
OpenVibeConnectionStimulationTest.java.txt
the main file using the VRPN client and calling Processing functions
(8.74 KiB) Downloaded 239 times
ProcessOVTargetStimulations.java.txt
the VRPN (button) client
(2 KiB) Downloaded 244 times

hatma
Posts: 12
Joined: Wed May 08, 2013 11:10 pm

Re: VRPN and Processing developing environment

Post by hatma »

fabien.lotte wrote:
To do so you have to use Java, since there is a VRPN library for java (which comes with the C++ VRPN library in the official package).
Dear fabien.lotte

where to download the library?

best regards
hatma

r0b0t1t0
Posts: 2
Joined: Fri Jul 19, 2013 4:13 pm

Re: VRPN and Processing developing environment

Post by r0b0t1t0 »

Hi!!

i'm having the same problem, where should i download those files?? the thing is that i'm working with ssvep example and it show me the following error:

from SSVEP_VRPN_startstop: No response from server for ...


and then in the example, don't show me the training screen.

Thx a lot!!

jlegeny
Posts: 239
Joined: Tue Nov 02, 2010 8:51 am
Location: Mensia Technologies Paris FR
Contact:

Re: VRPN and Processing developing environment

Post by jlegeny »

hello r0b0t1t0,

you do not need to download additional files for the included SSVEP scenarios and application.

The problem you are running into can be due to several things. By default Windows firewall will cut off any application trying to connect to any network service and display a window on which it will ask you whether you want to allow access. This window appears the first time you run the application, and it often appears behind! your current window.

Other problem could be that there is more than one instance of SSVEP stimulator running (for example due to previous attempts). In that case the VRPN connection will not work with the same error.

Cheers
Jozef

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