Search found 211 matches

by Thomas
Mon Mar 18, 2024 1:38 pm
Forum: Scenarios and BCI design
Topic: motor imaginary CSP online 4. xml crashes
Replies: 2
Views: 84

Re: motor imaginary CSP online 4. xml crashes

Hi,

In addition to Kyungho's answer, I had a look at the code, and the log actually means that you do not have any outputs on the box.
Have you changed any box configuration ?

I agree with Kyungho on the fact that upgrading to a newer version of OpenViBE would likely help.

Thomas
by Thomas
Wed Jan 31, 2024 9:59 am
Forum: Discussion about BCI and related topics
Topic: 3 Channel MI BCI
Replies: 5
Views: 456

Re: 3 Channel MI BCI

Hi,

You can try to run some motor imagery with only 3 channels, following the motor imagery exemples provided in OpenViBE.

Although it is possible, the low number of channels may lead to poor classification results.

Kind regards,
Thomas
by Thomas
Fri Jan 26, 2024 1:58 pm
Forum: OpenViBE News
Topic: OpenviBE 3.6.0 released
Replies: 0
Views: 732

OpenviBE 3.6.0 released

We are pleased to announce the release of OpenViBE-3.6.0 ( download ). This release comes with big a infrastructural update with the use of miniconda for the management of dependencies. This means that OpenViBE has now a more modern and harmonised dependency management across platforms. This notably...
by Thomas
Thu Jan 25, 2024 9:24 am
Forum: Scenarios and BCI design
Topic: Troubleshooting Brain Waves Monitoring
Replies: 4
Views: 172

Re: Troubleshooting Brain Waves Monitoring

Thanks for the details.

Could you also share your unity code to understand what are the values that you are logging ?

Thank you.
Thomas
by Thomas
Wed Jan 24, 2024 8:47 am
Forum: Scenarios and BCI design
Topic: Troubleshooting Brain Waves Monitoring
Replies: 4
Views: 172

Re: Troubleshooting Brain Waves Monitoring

Hi amemov, Thanks for your message. Unfortunately I don't know what settings you are using on each boxes of the scenario, but I am wondering, if the frequencies you are logging are not a sampling frequencies (the amount of samples per seconds) that are being received by Unity rather than the signal ...
by Thomas
Tue Jan 02, 2024 8:31 am
Forum: Scenarios and BCI design
Topic: Troubleshooting motor imagery spatial filter (mi-csp-2-train-CSP.xml)
Replies: 10
Views: 22020

Re: Troubleshooting motor imagery spatial filter (mi-csp-2-train-CSP.xml)

Hi,

That's strange indeed.

You could send me the files using any file transfer platform and I'll try to dig a bit more.

Thanks,
Thomas
by Thomas
Wed Dec 20, 2023 10:31 am
Forum: Boxes
Topic: GDF replay to XDF
Replies: 3
Views: 14459

Re: GDF replay to XDF

Hi Mike, If you were using OV 3.1, there is an issue with the stimulations recorded in GDF file in that version. If you are also recording stimulations, you might want to look at the following for explanation and fix: https://gitlab.inria.fr/openvibe/gdf-file-fixer/-/tree/master And you shouldn't ha...
by Thomas
Wed Dec 13, 2023 9:38 am
Forum: Boxes
Topic: GDF replay to XDF
Replies: 3
Views: 14459

Re: GDF replay to XDF

Hi Mike, There are some scale and offsets applied to data when storing to GDF. This could be the reason you are seeing differences. What version of OpenViBE are you using ? Note that from OpenViBE 3.3.1, when recording GDF with OpenViBE (GDF File Writer) and playing it back with OpenViBE (GDF File R...
by Thomas
Wed Dec 13, 2023 9:34 am
Forum: Scenarios and BCI design
Topic: Troubleshooting motor imagery spatial filter (mi-csp-2-train-CSP.xml)
Replies: 10
Views: 22020

Re: Troubleshooting motor imagery spatial filter (mi-csp-2-train-CSP.xml)

Hi membrane286, Did you make any progress on this ? The CSP Spatial Filter Trainer box is trying to get eigen vectors and eigen values from covariance matrices from its two signal inputs. The error message indicates that it failed at doing so. This could be for two reasons: - The matrix inversion on...
by Thomas
Fri Nov 24, 2023 3:15 pm
Forum: Designer
Topic: Saving Timestamps from Stimulations
Replies: 1
Views: 13471

Re: Saving Timestamps from Stimulations

Hi Faali002,

I've replied to the question on your post here.

Please let me know if my answer suits your needs.

Cheers,
Thomas
by Thomas
Fri Nov 24, 2023 3:13 pm
Forum: Discussion about OpenViBE
Topic: Timestamps for the Cues of Graz MI BCI Stimulator
Replies: 3
Views: 15026

Re: Timestamps for the Cues of Graz MI BCI Stimulator

Hi Faali002, You can save the stimulations in a CSV file with the CSV File Writer box. From OpenViBE 3.2.0 (although I suggest using the latest version of course), you can record stimulations only in a CSV file. For this you need to right click on the CSV File Writer box and select inputs > input 1 ...
by Thomas
Thu Nov 23, 2023 3:00 pm
Forum: Scenarios and BCI design
Topic: Time based epoching Box
Replies: 4
Views: 6162

Re: Time based epoching Box

Hi illusion, I looked at the data you sent me and understood what is going on. Basically, there are more features than expected because the TimeBaseEpoching creates more epochs than excpected. However this is not really a bug. This is due to the "epoching offset / sampling rate" ratio. If I take the...
by Thomas
Thu Nov 09, 2023 10:59 am
Forum: Scenarios and BCI design
Topic: Time based epoching Box
Replies: 4
Views: 6162

Re: Time based epoching Box

Hi illusion, Thanks for the detailed message. Indeed, numbers are not matching. I just tried with the default data file provided with OpenViBE saving data in CSV files to count samples, and the counts are ok for me. The Time Based Epoching is actually going from 0.5 to 4.5 seconds (starts at 0.5 and...
by Thomas
Thu Nov 09, 2023 10:06 am
Forum: Boxes
Topic: how to run classifier online and with pre=recorded EEG
Replies: 3
Views: 6885

Re: how to run classifier online and with pre=recorded EEG

Hi Jeff, Indeed you don't want to use the StimulationBasedEpoching since it would mean that you already know the class, and therefore don't need the classifier... The StimulationBasedEpoching is only needed for training, to filter each class in the corresponding input the classifier trainer. If you ...
by Thomas
Thu Nov 09, 2023 9:31 am
Forum: Box and application development
Topic: Graphic card crash / overflowing system load
Replies: 4
Views: 7586

Re: Graphic card crash / overflowing system load

Hi Esteban, Thanks for all the clarification. I didn't focus too much on the EDF File write, but now that you mention it, this box stores all the data it receives until the scenario stops, and then write it to the file. Until the data is written the file, it's stored in RAM of course, which explains...