DataHub
| Developer(s) | Christian Kothe; Chadwick Boulay. |
|---|---|
| Development status | -in development- |
| Written in | C, C++, Python, Java, C#, MATLAB |
| Operating system | Windows, Linux, MacOS, Android, iOS |
| Type | Data collection |
| License | Open source |
| Website | LSL webpage |
Resources
| Downloads | |
|---|---|
| Manuals | |
| Templates | |
The DataHub Makes use of the lab streaming layer. The lab streaming layer (LSL) is a system for the unified collection of measurement time series in research experiments that handles both the networking, time-synchronization, (near-) real-time access as well as optionally the centralized collection, viewing and disk recording of the data.
Installation
Our support for LSL is mainly done in python. Download python here: Please choose a 64 bit version.. Run the installer and make sure to add Python to the file path (it's an option in the installer).
Open a command prompt, start with upgrading the pip installer by typing:
c:>python -m pip install --upgrade pip
Then:
c:>pip install pylsl
more info: cross platform pylsl
Versions
The TSG uses the version 1.15.0. Open a command and type the following to find the version used:
c:>python
>>> import pylsl
>>> print(pylsl.__version__)
Usage
Python
Example demonstrating how to send LSL stream and marker data:
1#!/usr/bin/env python3.10
2# -*- coding: utf-8 -*-
3
4import time
5import random
6import keyboard
7from pylsl import StreamInfo, StreamOutlet
8
9from pylsl import local_clock
10
11# --- Setup Marker Stream ---
12print("Setting up marker stream...")
13marker_info = StreamInfo(
14 name="MarkerStream",
15 type="Markers",
16 channel_count=1,
17 nominal_srate=0, # Irregular sampling
18 channel_format="string",
19 source_id="MarkerSource"
20)
21marker_outlet = StreamOutlet(marker_info, chunk_size=1)
22
23# --- Setup Data Stream ---
24print("Setting up data stream...")
25data_info = StreamInfo(
26 name="TestStream",
27 type="TestData",
28 channel_count=4,
29 nominal_srate=100,
30 channel_format="float32",
31 source_id="TestStream_Source"
32)
33
34channels = data_info.desc().append_child("channels")
35for name in ["A", "B", "C", "D"]:
36 chan = channels.append_child("channel")
37 chan.append_child_value("name", name)
38 chan.append_child_value("unit", "unitless")
39 chan.append_child_value("type", "TestData")
40
41data_outlet = StreamOutlet(data_info, chunk_size=1)
42
43# --- Start Streaming ---
44print("Start streaming... Press 'q' to stop.")
45marker_outlet.push_sample(["Start"])
46
47while not keyboard.is_pressed('q'):
48 random_numbers = [random.randint(1, 2) for _ in range(4)]
49 data_outlet.push_sample(random_numbers)
50 time.sleep(0.01)
51
52marker_outlet.push_sample(["Stop"])
53print("Streaming stopped.")
Matlab
Please, read the instructions on the GitHub labstreaminglayer website (https://github.com/labstreaminglayer/liblsl-Matlab) on how to prepare Matlab to work with LSL. You can either use the latest release for your Matlab version, or if that doesn't workout well, build it from the source files. Make sure to add the liblsl-Matlab folder to your path recursively to make it available to your own scripts.
A short example for sending lsl streaming data:
1%% instantiate the library
2disp('Loading library...');
3lib = lsl_loadlib();
4
5% make a new stream outlet
6disp('Creating a new streaminfo...');
7info = lsl_streaminfo(lib,'BioSemi','EEG',8,100,'cf_float32','sdfwerr32432');
8
9disp('Opening an outlet...');
10outlet = lsl_outlet(info);
11
12% send data into the outlet, sample by sample
13disp('Now transmitting data...');
14while true
15 outlet.push_sample(randn(8,1));
16 pause(0.01);
17end
A short example for receiving lsl streaming data:
1%% instantiate the library
2disp('Loading the library...');
3lib = lsl_loadlib();
4
5% resolve a stream...
6disp('Resolving an EEG stream...');
7result = {};
8while isempty(result)
9 result = lsl_resolve_byprop(lib,'type','EEG'); end
10
11% create a new inlet
12disp('Opening an inlet...');
13inlet = lsl_inlet(result{1});
14
15disp('Now receiving data...');
16while true
17 % get data from the inlet
18 [vec,ts] = inlet.pull_sample();
19 % and display it
20 fprintf('%.2f\t',vec);
21 fprintf('%.5f\n',ts);
22end