OpenViBE forum

Hello, to setup a baseline scenario, you could use the lua scripting box to generate stimulations indicating the beginning and end of the baseline, and indicate to the user these stimulations with a sound (sound player box) or a picture for instance (display cue image box). Then you record/extract t...

Dear Patrick, I have never experimented myself with estimating engagement in EEG signals, but you could probably look at the following paper to try to reproduce what they did for instance: Berka, C., Levendowski, D. J., Lumicao, M. N., Yau, A., Davis, G., Zivkovic, V. T., ... & Craven, P. L. (2007)....

Dear Erin, Indeed, you could setup an auditory oddball using the Lua stimulator rather than the clock stimulator. Using a Lua script you can basically send stimulation whenever you want, including with variable intervals between trials/stimulations. I would recommand you to look at the lua script wh...

Dear Ryana, Indeed, you should use the lua stimulator to use these applications online. For the handball game, you can use the same lua script as the one used in the motor imagery scenario (e.g., the motor-imagery-bci-graz-stimulator.lua script that you can find in the motor-imagery-CSP scenarios di...

Hello all, just a quick information (I unfortunately do not have time to look into the scenarios in details): If you want to do P300 recognition from EEG signals with only two channels, I would suggest to use channels Cz or Pz for instance, and if you have 3 channels, Fz, Cz and Pz, see, e.g., the f...

Dear Morozov, To complement what Jussi has said, you can also look at the videolectures website, there are a number of tutorials on EEG signal processing and classification: http://videolectures.net/Top/Technology/Neurotechnology/ As Jussi said, you can start by using the motor imagery scenario from...

in the SSVEP scenario, squaring a signal band-pass filtered in a given frequency band and then averaging it over time actually means computing the power of the signal in that band. Alternatively you could indeed also use an FFT to compute the power of the signal in a given frequency bin, this would ...

That does sound possible indeed: some research groups have done that to classify images (among a flow of various images) based on a similar principle. They used ERP (Event Related Potentials) following image appearance to classify it as a target image or not (e.g., for military applications, to dete...

Dear Jackomo, Welcome to the openvibe forum! There does not seem to be anything particularly wrong with your scenario from the description you gave. Maybe you could send around your actual openvibe scenarios so we can look at them into more details? For information, a cross-validation accuracy of 65...

Hello Beginner, I have never heard of this PeerJ journal before, does anybody know this journal and its quality? At least, in the BCI community this journal is completely unknown and I didn't see anyone from this community in the scientific editors of this journal. That does not mean this paper/jour...

No there is no such scenario so far, the available scenarios being only BCI scenarios (so using only brain activity, not EOG/EMG artefacts recorded using EEG signals).
However it should be possible to build such a scenario with OpenViBE, so don't hesitate to share such a scenario if you make one!

Hi Roberto, Regarding your first question (normalization): - using the univariate statistic box, you should be able to compute the mean and variance of each of your feature (which the box can compute). - Once you got these mean/variance for each feature, you can normalize your features using the sim...

Hi Roberto, The output of the SVM in openvibe is between 0 and 1: if the outcome is closer to 0 it means the input data comes from one class, if it is closer to 1 it means the input data comes from the other class. In contrast, the LDA in openvibe gives an output which is negative if the input data ...

Dear Pwierzgala. I am glad that you have found the answer to your question, and thank you for sharing it! I am sorry that nobody answered you so far, but I guessed your question was an easy question only for people who have already tried to do what you want to do, which is in fact very specific (per...

Hello, I don't know exactly what kind of EMG processing you would like to do, but there are already a number of generic signal processing boxes in OpenVIBE (see http://openvibe.inria.fr/documentation/unstable/Doc_BoxAlgorithms.html ), to filter the signals, apply basic mathematical operations on it,...