OpenViBE forum

Dear Openvibe team

In the file p300-speller-3-train-classifier.xml, from my understanding, the classifier training starts when the box 'classifier trainer' receives the OVTK_StimulationId_Train stimulation. Could you please tell me which box sends this stimulation? I checked the box 'Lua Stimulator' and its code ovpCBoxAlgorithmLuaStimulator.cpp but couldn't find it. My P300 speller code sometimes cannot start classifier training process and I believe it has not received the stimulation 'OVTK_StimulationId_Train'.

Thank you very much

-Jim

Hi Jim,

The Lua Stimulator executes Lua script, where the stimulations are sent and received.
In the classifier training scenario, the OVTK_StimulationId_Train stimulation is sent by the File reader.

As you can see in the acquisition scenario, this file contains the stimulation stream coming from the Lua Stimulator.

When you look at the Lua script p300-speller-target.lua, you can see that the OVTK_StimulationId_Train stimulation is sent when the Lua box receives OVTK_StimulationId_ExperimentStop, that comes from the P300 Speller Stimulator named "Flashing sequence".

Anyway, you can always trigger manually the training by using a defined stimulation in the classifier trainer, and a Keyboard stimulator.
For example, begin training with OVTK_StimulationId_Label_01.
Fast forward the scenario, and when you are sure that all data have been processed (time counter superior to the session duration), press 'a' in the keyboard stimulator. This should manually trigger the training.

hope this helps!

Laurent-

_________________
Follow us on twitter >> openvibebci

Checkout my (old) blog for some OpenViBE tips & tricks : here !

Dear Laurent

Thank you very much for your reply. I ended up adding a text in LuAstimulator.cpp to show that OVTK_StimulationId_Train has already been sent to make sure that I don't miss it. .

-Jim

Hi Jim,

If this solution fits your needs, I guess it's ok

However I must tell you again... Modifying the Lua Stimulator box itself is not the wisest/easiest solution.
Lua is a powerful scripting language, and you don't have to recompile everything after each modification of the script executed by the box

Bye

Laurent-

_________________
Follow us on twitter >> openvibebci

Checkout my (old) blog for some OpenViBE tips & tricks : here !