What's the use of the codes in"Open BCI Sketch"?
Hello, I tried to measure EOG with Ganglion. I imported each code of "Open BCI Sketch" into processing one by one and ran it, but the results in the Open BCI GUI didn't seem to make a significant difference. What does each code in Open BCI Sketch mean and what can it be used for?
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Hi, Cui,
I am unclear WHY you are running the GUI inside Processing? Almost all OpenBCI users are better off, just using the 'standalone' pre-compiled binaries on the Downloads page:
https://openbci.com/downloads
The reason the GUI files are provided, are to help users who want to make customizations to the GUI code or add their own custom features.
https://github.com/OpenBCI/OpenBCI_GUI/tree/master/OpenBCI_GUI
If you are not in that category of adding code, then you should be using the Downloads version. The files shown in the link above and your screenshot, are ALL component source files for the GUI. These are '.pde' files that are interpreted by the Processing language. They are NOT to be 'imported' and run separately. Please study the Getting Started tutorials.
https://docs.openbci.com/GettingStarted/GettingStartedLanding/
Your desire to measure EOG is most similar to the EMG tutorial.
William
Hello, I have to import any program from Sketch to run the Open BCI GUI, does that mean I can open any program?
By the way, I found a question when I was collecting EOG. According to the theory, when my eyeballs are moving horizontally or vertically, EOG is a square wave. But there seems to be a program that prevents baseline shift from showing square waves, as shown in the image (I guess this waveform is not original). How do I make it display the original square wave pattern?And is it related to filtering? Is the 0.5Hz filtering software or hardware?
I'm just not understanding what you are trying to accomplish with the GUI. Did you read my earlier links? The standalone GUI does not need the Processing app and does not 'import' sketches or programs. Just follow the Getting Started tutorials and forget about running the GUI from the Processing app.
EEG amplifiers can be 'DC-coupled', that is, capable of accurately reproducing the EOG DC wave forms. Cyton (ADS1299 chip) is an example of this.
Ganglion is NOT DC-coupled. So distorts the DC waveforms. But you can still see the general effect. Ganglion is capable of EEG, ECG, and EMG. But limited as you see with EOG.
OK, I got it!Thanks.
But this is a question for me, how do I get it to show a square wave?
You cannot obtain an EOG square wave from Ganglion. It is not capable of returning pure DC potentials. I'm sure you could derive some type of signal processing on the samples and determine which direction the eyes are looking. In general, in EEG applications, EOG is mainly used to de-artifact the EEG. Not as a separate signal to track.
Just ignore the DC levels, and detect on the sharp signal transitions up or down. For example running a high-pass filter on the samples will tend to ignore the distorted DC levels and emphasize the sharp transitions.
OK,I’ll try to write a post-processing program.Thakns again!