event marker from matlab

Forum for discussion on different signal processing algorithms
Post Reply
imenefeki
Posts: 6
Joined: 29 Apr 2015, 08:08

event marker from matlab

Post by imenefeki » 30 Apr 2015, 05:07

Hi
i do the signal acquisition in matlab using FieldTrip Buffer then now i need to send the events marker from matlab to BCI2000 to use this states on offline.
How can i send the events marker ? thans you for your help !

pbrunner
Posts: 344
Joined: 17 Sep 2010, 12:43

Re: event marker from matlab

Post by pbrunner » 30 Apr 2015, 10:01

Please see the tutorial on events in the following BCI2000 Field Trip tutorial:

http://www.bci2000.org/wiki/index.php/P ... rip_buffer

Regards, Peter

imenefeki
Posts: 6
Joined: 29 Apr 2015, 08:08

Re: event marker from matlab

Post by imenefeki » 30 Apr 2015, 10:11

i try this but i need to write the markers event of the desynchronisation of mu and beta band . this event used in Feedback application!

pbrunner
Posts: 344
Joined: 17 Sep 2010, 12:43

Re: event marker from matlab

Post by pbrunner » 30 Apr 2015, 11:13

I am not sure if your use of Field Trip will work as the BCI2000 integration is only intended for signal processing and not for signal acquisition. But perhaps I do not fully understand your setup. Can you please provide a description of it?

As for the Field Trip event, you should be able to write back any state, as long as it exists in BCI2000 and as long as you have added it to FTStatesFromBuffer. An example is listed in the following thread:

http://www.bci2000.org/phpbb/viewtopic.php?t=1281

Regards, Peter

imenefeki
Posts: 6
Joined: 29 Apr 2015, 08:08

Re: event marker from matlab

Post by imenefeki » 30 Apr 2015, 12:11

thans Brunner for the ansewer.
i use FieldTripBuffer as an interface between BCI2000 ET MATLAB . i use the row data in matlab to calculate the power signal then matlab return a trigger to be recorded with the data row in real time! How can i send the trigger ? i should send it to BCI2000 or to the buffer ?

pbrunner
Posts: 344
Joined: 17 Sep 2010, 12:43

Re: event marker from matlab

Post by pbrunner » 30 Apr 2015, 14:51

I still do not fully understand the system that you would like to build. For example, if you are using BCI2000 to acquire data and File Trip to apply extract the signal power, then you could just use the HilbertFilter within BCI2000 without needing Field Trip.

http://www.bci2000.org/wiki/index.php/C ... bertFilter


If on the other hand you acquiring the data in Field Trip and try to pass it back to BCI2000 then this probably won't work as intended, BCI2000 will not store the data for offline inspection.


If for whatever reason you need to send markers back to BCI2000 from a Field Trip buffer, then you are limited to one marker per block cycle as detailed in the following thread:

http://www.bci2000.org/wiki/index.php/C ... bertFilter


Regards, Peter

imenefeki
Posts: 6
Joined: 29 Apr 2015, 08:08

Re: event marker from matlab

Post by imenefeki » 30 Apr 2015, 16:19

Thanks you so much for help ! it so clear to me now .

pbrunner
Posts: 344
Joined: 17 Sep 2010, 12:43

Re: event marker from matlab

Post by pbrunner » 30 Apr 2015, 17:48

You are welcome.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest