OpenViBE forum

Hi Jeff, So I had a look at the code because there error messages were a bit surprising to me. I realised that the implementation of the EOG Denoising Calibration box does not play well with the stimulation based epoching. Indeed, the box automatically triggers the calibration processing when it sto...

Hi Jeff, What I can see from your screenshot is that the pipeline was too demanding and the real-time was not managed. I tested the scenario on some data I have here, with 96 channels, but could not reproduce the latency issue. What sampling frequency are you using in your data acquisition ? Would y...

Jeff, You can merge to signals together into one with the Signal Merge box ( documentaiton ). When you ran the scenario through the whole data, the display stopped because there was no more data, but the scenario kept running since it didn't know it had to stop. A Player Controller box is needed in ...

Hi Jeff, I see the epochs are generated on the OVTK_StimulationId_Number_03 stimulation. I guess there are quite a few in the data file. If you want the CWT to be calculated on the first epoch only, you could put in place a mecanism to stop the scenario when reaching the second epoch. To do so, you ...

Jeff, There are two options, First the easiest, is there a stimulation at the end of your EEG data ? It doesn't matter which stimulation it is, but it is important that it is unique in the stream and marking the end of the stream. If there is such a stim at the end of the file, then you can use it a...

The output of the CWT analysis is compatible with the StreamedMatrix stream type. Therefore you can write each of the outputs of the Continuous Wavelet Analysis box by connecting it to a CSV File Writer box (for a human readable output), or any other file writer box. The thing is that the file write...

Yes indeed that box documentation is quite light. If you double click on the box, you will see its two settings: The first one is the stimulation it is expecting in order to perform an action, here you want to write "OVTK_StimulationId_TrainCompleted" The second one is the action to perform, you wan...

Hi Jeff, First of all the scenario looks fine. As the the error message states, the box is not happy with the equation you typed. Indeed, the box is processing the incoming signals but does not know the channels F9, Fp1, etc. The variables that can be used are the letter of the alphabet in the same ...

Hi Jeff, Sorry for not replying earlier. I think you can use the Simple DSP box ( documentation ). You can use it with 2 inputs, one being a signal containing F9 and the other a signal containing F10, and type "a-b" as the equation. You can filter F9 and F10 from your signal using the "Channel Selec...

Hi Jeff,

I don't know if you've seen it already, but there is a Continuous Wavelet Analysis box in OpenViBE.

Here its documentation page: http://openvibe.inria.fr//documentation ... lysis.html

Hope this helps,
Thomas

I Jeff, Sorry my previous reply may have been ambiguous. By "double-arrow" button, I was referring to the button in between the "play" and the "double blue arrows" button. If you hover over it, it will say "executes the scenario as fast as possible" . The player Controller box, is configurable to do...

Hi Jeff,

There might be boxes to help you out with this one.
Could you explain a bit more how you want to achieve this ? Are you looking for classificaiton boxes, or some maths to process F9-F10 ?

Thanks,
Thomas

Hi Jeff, Thanks for the details and screenshots. Q1: The keyboard stimulator is here so that you set the sart and end point of the data that will be used for calibration. Let's say your input file is 5 minutes long, if you press 'a' at 1min and 'u' at 3mn, then calibration will be done on the data b...

Hi Jeff, Luckily you are indeed not the only one wanting to do this and it is therefore possible in OpenViBE. When you want to run a scenario reading a file for offline processing, instead of pressing the play button you can click on the double-arrow on the right side of the play button. This will e...

Hi Allen, Thanks for sharing your issues on the forum. Note that at the moment, the OpenViBE build should work on Ubuntu 18.04 & 20.04 as well as on Fedora 31. Any other version might require some work. From the log, I suspect you are running a OS that's neither Ubuntu or Fedora. You can modify the ...