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<p style="margin-top:0;margin-bottom:0">Hi all,</p>
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<p style="margin-top:0;margin-bottom:0"> I have been using Fieldtrip for the past few years for my offline EEG analysis, with good success. Recently, I have switched to helping build and design some online brain-computer interface systems and was looking toward
Fieldtrip to handle the signal processing aspect in real-time. However, I am having some trouble with getting the online EEG processing to work as I'd like. I was wondering if any of you could provide some guidance on getting started (and potentially optimization
areas) for the online EEG analysis from Fieldtrip, based on our setup below.<br>
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<p style="margin-top:0;margin-bottom:0">Details:<br>
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<p style="margin-top:0;margin-bottom:0">We are using the LabStreamingLayer (LSL) synchronization system to read in raw EEG data from a g.tec USB amplifier. I know that Fieldtrip has its own online buffer, but for various reasons we'd prefer to use the LSL system
to link together our EEG recording, Matlab processing, stimulus input/output.</p>
<p style="margin-top:0;margin-bottom:0">Data from the amplifier is brought in to Matlab through LSL, providing raw Chan X Sample data. We are establishing the header for Fieldtrip ourselves, inputting the required points to use the ft_datatype_raw format. We
have to use the raw datatype as the header information output is not in Fieldtrip's standard format. This allows us to run ft_preprocessing after defining a cfg of our choice.</p>
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<p style="margin-top:0;margin-bottom:0">However, just doing this processes takes around 1.5-1.8 seconds for Matlab to processes each EEG data chunk. We haven't even yet included
<span>any of the ft_analysis schemes for feature extraction, and are concerned the processing time might be too delayed through this route for real-time BCI. Does anyone have any experience with online BCI processing through Fieldtrip, or recommendations on
expediting this process? <br>
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<p style="margin-top:0;margin-bottom:0"><span>Thank you in advance for your help!
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<p style="margin-top:0;margin-bottom:0"><span>-Eli</span><br>
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