OpenBCI Forum OpenBCI Forum
Sign In · Register
Sign In · Register
Categories
Discussions
Activity
Sign In · Register
Home › Search
  1. Questions about the focus widget

    Andrey1994
    by Andrey1994 · May 2021
    There is no training phase, predefined coefficients are used.
  2. OpenVibe: motor-imagery-bci-2-classifier [resolved]

    mhadji05
    by mhadji05 · April 2021
    In the Surface Laplacian Box -> Spatial Filter coefficients there is this (4; 0; -1; 0; -1; -1; 0; 0; -1; 0; 0; 4; 0; -1; 0; 0; -1; -1; 0; -1)
  3. Adding FILTERS to the openBCI_GUI

    nejemia
    by nejemia · October 2020
    Widget. Is there any place I can get the coefficients without running the Matlab (I do not have the DSP Toolbox....).
  4. Adding FILTERS to the openBCI_GUI

    eegstud24
    by eegstud24 · May 2020
    I tried to add a 16-24 Hz bandpass filter recently, so if you need an example you can look at the link below that shows the changes I made to the widget. Note that you need access to Matlab or some ot
  5. SampleIndex drops and the order of index is not right

    jnvandermeer
    by jnvandermeer · April 2020
    Packet loss is only bad if the 50 Hz noise is really high, and the srate is 125 Hz. Then the notch filter goes crazy if one packet is lost, and you see a burst because the on-line filter coefficients
  6. large millivolt data values / FbEEG Full Band EEG

    wjcroft
    by wjcroft · May 2019
    In terms of removing the DC offset, all you have to be concerned with is removing components below say .5 Hz. So that can be achieved for example with a Butterworth bandpass from .5 to 45 Hz, or a hig
  7. what are the filters needed when using python to process Cyton RAW data

    EdmundWang
    by EdmundWang · November 2018
    # 2) Calculate the coefficients, store in variables
  8. How to choose the coefficients for a Surface LaPlacian filter (spatial filter)?

    hackr
    by hackr · September 2017
    @Paski Thanks for the link. I guess I'm trying to better understand the logic for determining the coefficients that they use. That way, I can understand how to change their values to try to improve my
  9. How to choose the coefficients for a Surface LaPlacian filter (spatial filter)?

    Paski
    by Paski · September 2017
    Hi Hackr, see this link. There you will find the coefficients. https://www.bci2000.org/mediawiki/index.php/User_Tutorial:Configuring_Online_Feedback
  10. How to choose the coefficients for a Surface LaPlacian filter (spatial filter)?

    hackr
    by hackr · September 2017
    In the OpenViBE classification examples, they have this spatial filter labeled LaPlacian Surface. It takes 2 coefficients for every 1 input channel as parameters. I am wondering how one goes about det
  11. detecting 150 and 200 Hz in GUI

    wjcroft
    by wjcroft · February 2017
    If you are in the U.S., you want to have a notch filter at 60 Hz, to cancel out mains noise. There are tutorials on the web on how to construct the filter coefficients. And also some here,
  12. detecting 150 and 200 Hz in GUI

    krupalmistry
    by krupalmistry · February 2017
    For peak detection around 60 Hz, how to change the filter coefficients? 
  13. detecting 150 and 200 Hz in GUI

    wjcroft
    by wjcroft · February 2017
    3. Filter coefficients can be changed.
  14. GUI v2 freezing, wrong sample rate?

    djfletch42
    by djfletch42 · January 2017
    Sorry, that was just copy and pasted from the original code. I didn't finish editing the comments. Those coefficients are for the 125Hz sampling rate. I did clone the distribution from github, but I f
  15. GUI v2 freezing, wrong sample rate?

    pushtheworld
    by pushtheworld · January 2017
    @djfletch42 the ganglion was originally 256Hz, then BLE said nope, and it's 200Hz. Thanks so much for taking a crack at the filter coefficients, I will add this to the patch.
  16. GUI v2 freezing, wrong sample rate?

    djfletch42
    by djfletch42 · January 2017
    In case it's helpful, I did go through and calculate the filter coefficients for the 125Hz sampling rate. This code will incorporate the new filter coefficients into DataProcessing.pde. I used Matlab
  17. Buying Dry / Active Electrodes

    wjcroft
    by wjcroft · November 2015
    no significant effects . Bivariate correlation coefficients were calculated to assess the relationship between electrode pairs during the simultaneous in vivo recordings, indicating a significant pos
  18. Butterworth vs Bessel DSP bandpass filters

    dschoepf
    by dschoepf · October 2015
    I was just wondering why the Butterworth filter was selected for all filtering in the EEG Processing.  I imagine the maximally flat frequency response is the enviable characteristic, but wouldn't a Be
  19. DSP Digital Signal Processing basics

    wjcroft
    by wjcroft · June 2015
    The filters and FFT in OpenBCI_GUI are also great examples. Second link above shows how the filter coefficients can be modified for your application.
  20. filter phase delays / Fidlib, MNE-Python

    chipaudette
    by chipaudette · March 2015
    will need to be much longer (ie, have many more coefficients) that an IIR filter with the same roll-off.
Next

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Sign In Register

© Vanilla Keystone Theme 2026

Powered By Vanilla