[Newbie question] about TCP Tagging

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seanypoo
Posts: 7
Joined: Wed Feb 22, 2017 5:55 pm

[Newbie question] about TCP Tagging

Post by seanypoo »

Hello

Could some developers provide a better tutorial about TCP Tagging please?

I have read many times http://openvibe.inria.fr/tcp-tagging/. still very confuse.

The examples (Python, Java, C++) provided on the site is for any external applicaitons.

What about if I dont have an applicaiton, If I only use the P300 speller acquisition xml example.

under C++ example, It also said "The class is used by e.g. the P300 Stimulator and Graz Visualization boxes bundled with OpenViBE."

so, How to use tcp tagging to add event marker into it?

Do I need modify the codes of any boxes in P300 speller acquisition?

Thanks
Sean

jtlindgren
Posts: 778
Joined: Tue Dec 04, 2012 3:53 pm
Location: INRIA Rennes, FRANCE

Re: [Newbie question] about TCP Tagging

Post by jtlindgren »

Hi Sean,

openvibe boxes such as the P300 Stimulator and Graz Visu use the TCP Tagging C++ client code to connect to the Acquisition Server's TCP Tagging module (server). If you send such boxes some stimulation they don't recognize, they just pass it through the server as-is. There's currently no box to just send stimulations to the server.


Cheers,
Jussi

seanypoo
Posts: 7
Joined: Wed Feb 22, 2017 5:55 pm

Re: [Newbie question] about TCP Tagging

Post by seanypoo »

So, Does it mean the TCP Tagging C++ client code has to run parallel with P300 Stimulator? If this is correct.
Typically the client is used as a class inside the Stimulator code itself, hopefully in such at thread that is able to send the stimulation asap after the corresponding event is rendered.
I ran the P300-xdawn-acquisition.xml example AND tcp-tagging-client.py together. I should get this data is correct (I mean the format is correct). see below:
These are independent. The python client is just an illustration how to send a stimulation to the server using Python.


Image
After the three columns data is the EEG data.
If thats stimulation stream directed to CSV file, the last column is the stimulation duration. If you use P300 Stimulator and the python script together, what you should see in such a file is a union of stimulations sent by both (both of them work as separate clients).
Now, If I refer to the diagram from http://openvibe.inria.fr/send-stimulati ... on-server/
As mentioned, the document is deprecated and should be used only for illustration of previous techniques. The second picture you've made doesn't seem appropriate, the idea is that if your stimulator *is an external application* (whereas in OpenVibE P300 scenarios *it is not*), then the TCP Tagging client should be used *inside* that external application and it should send the stimulations to the Acquisition Server after the corresponding events (e.g. flashes) have been rendered. By stimulator in this case I mean whatever visualization/rendering tool that is playing the events. Right after the event has been shown to the user, the corresponding stimulation should be sent to the TCP Tagging (in the server).

Hope this helps,
Jussi

seanypoo
Posts: 7
Joined: Wed Feb 22, 2017 5:55 pm

Re: [Newbie question] about TCP Tagging

Post by seanypoo »

Thanks Jussi, I feel much clear now. Cheers Sean.

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