Markers#

This section demonstrates how to create an LSL (Lab Streaming Layer) stream with markers using the BrainAccess Board library.

For this example to work:

  1. Ensure that the BrainAccess Board is running and the device is properly connected.

  2. Run the example code provided below.

  3. Open the BrainAccess Board application and connect the Marker stream:

    • Go to the Configuration tab.

    • Select Lab Streaming Layer (LSL) in the “Select Source” dropdown menu.

    • Choose the marker stream and press Connect.

  4. View the markers in the viewer application.

Example: Creating a Marker Stream#

import time
import brainaccess_board as bb

# Create an LSL stream with markers
stim = bb.stimulation_connect(name="BrainAccessMarkers")

# Check if there are consumers for the stream
number = 0
print("Markers will not be sent until Markers LSL stream is connected to BrainAccess Board.")
while True:
    if stim.have_consumers():
        # Send a marker
        stim.annotate(str(number))
        print(f"Sent marker: {number}")
        number += 1
        time.sleep(1)

Description#

  • Creating the LSL Stream: The function stimulation_connect() establishes an LSL stream with the specified name (BrainAccessMarkers in this example).

  • Checking Consumers: The method have_consumers() checks if any applications are currently receiving data from this stream.

  • Sending Markers: The method annotate() sends a marker (str(number) in the example code) to the stream.

Use this setup to send markers in real-time for event tracking in experiments.