Lab Streaming Layer

Push raw EEG samples to the LSL network. Discoverable by OpenViBE, MNE-LSL, BCI2000, NeuroPype, LabRecorder.

pieeg-server --lsl                    # enable on startup
pieeg-server --lsl --lsl-name MyEEG   # custom stream name

Toggle at runtime via dashboard or WebSocket (lsl_start / lsl_stop).

Receive in Python

from pylsl import StreamInlet, resolve_stream
 
streams = resolve_stream('name', 'PiEEG')
inlet = StreamInlet(streams[0])
sample, timestamp = inlet.pull_sample()

WebSocket Control

{"cmd": "lsl_start"}
{"cmd": "lsl_stop"}
{"cmd": "lsl_status"}
{"cmd": "lsl_groups_get"}
{"cmd": "lsl_groups_set", "groups": [
  {"name": "EEG", "channels": [0, 1, 2, 3, 4, 5, 6]},
  {"name": "EOG", "channels": [7]}
]}

Channel Groups

Configure multiple LSL outlets, each streaming a subset of channels. Useful for separating EEG from EOG/EMG channels.

Interactive Setup

Use the regions setup wizard to define channel groups interactively:

pieeg-server --osc-regions-setup

This creates ~/.pieeg/lsl_groups.json that both OSC and LSL integrations use.

WebSocket Configuration

Example: Split 8-channel stream into EEG (Ch0–6) and EOG (Ch7):

{"cmd": "lsl_groups_set", "groups": [
  {"name": "EEG", "channels": [0, 1, 2, 3, 4, 5, 6]},
  {"name": "EOG", "channels": [7]}
]}

Each group creates a separate LSL stream named {GroupName}_{StreamName} (e.g., EEG_PiEEG, EOG_PiEEG).

If no groups are configured, a single default outlet streams all channels.

Stream Properties

Compatible Software

• OpenViBE — BCI design & experimentation
• MNE-Python — MEG/EEG analysis
• BCI2000 — general-purpose BCI system
• NeuroPype — neural data processing pipelines
• LabRecorder — LSL stream recording