save FFT data and band data in a file?

Comments

• wjcroft Mount Shasta, CA

  February 2023

  The Networking Widget allows sending FFT or Bands to other apps. So you could send via LSL to OpenViBE and write a file there.

  https://docs.openbci.com/Software/OpenBCISoftware/GUIWidgets/#networking
  http://openvibe.inria.fr/how-to-use-labstreaminglayer-in-openvibe/
  http://openvibe.inria.fr/documentation/3.3.0/Doc_BoxAlgorithm_CSVFileWriter.html

  There is no direct file output of these streams.
• lunarbrain India

  February 2023

  @wjcroft thank you so much again. I figured that out already. I will share an app with the community soon.
• lunarbrain India

  February 2023

  Here is the sample app to get the stream of band power data from OpenBCI GUI via UDP connection to write to files. Also, we can't send FFT data.

      const dgram = require('dgram')
      const server = dgram.createSocket('udp4')
      const fs = require('fs')
      const log = []
  
      // create seperate log files for channels 
      for (let i = 0; i < 15; i++) {
          log[i] = fs.createWriteStream(`ch-${i}-bandpower.csv`, {
              flags: 'a'
          });
      }
  
      // listen to UDP server from OpenBCI GUI
      server.on('listening', () => {
          console.log("UDP server listening")
      })
  
      // read new data from UDP Stream
      server.on('message', (msg, rinfo) => {
  
          // convert buffer data to utf8 format 
          const stream = msg.toString('utf8')
  
          // conver string to json and get data object 
          const bandpower = JSON.parse(stream).data
  
          // iterate over data object to get bandpower associated with each channel 
          for (let i = 0; i < bandpower.length - 1; i++) {
              log[i].write(`${bandpower[i]}\n`);
          }
      })
  
      const PORT = 12345
      const HOST = '127.0.0.1'
      server.bind(PORT, HOST)