liblsl.dart: Lab Streaming Layer for Dart and Flutter, XDF reader and LSL Viewer

Dart and Flutter tools for Lab Streaming Layer (LSL) and XDF recordings: the liblsl bindings, a pure-Dart XDF reader and writer, and LSL Viewer, an XDF file viewer and LSL stream viewer for desktop, Android and the web.

LSL Viewer: XDF file viewer and LSL stream viewer

• Open XDF files (LabRecorder recordings) of any size, one tab per stream, in the browser (read locally, never uploaded) or on the desktop.
• View live LSL streams with filters, re-referencing, power spectra, signal quality and trigger decoding.
• Record LSL streams to XDF, and replay XDF recordings as LSL streams.
• Share LSL over the network: a WebSocket bridge and relay, so browsers can view and publish streams, and streams can cross networks multicast doesn't reach.
• OpenBCI Cyton and serial devices, including over WebSerial in the browser.

---

---

Open the web app · Downloads for Windows, macOS, Linux and Android (lsl_viewer <version> releases; desktop archives include the lsl command line tool) · Website · Bridge and relay setup guide · Source

Packages

Package	What it is
liblsl	Dart/Flutter bindings for liblsl, with full parity with the C library (JOSS paper)
xdf	Read and write XDF files in pure Dart (all platforms, including the web); pyxdf's algorithms, tested against pyxdf
signal_core	Format-agnostic multichannel signal engine (summary pyramids, filters) behind the viewer and xdf
lsl_tools	Record to XDF, the WebSocket bridge/relay, test outlets, and the lsl command line tool
lsl_viewer	The LSL Viewer app, built from signal_viewer and its _lsl, _xdf and _serial source providers
liblsl_test	Integration tests to try liblsl with Flutter on any platform
liblsl_timing / liblsl_analysis	Multi-device latency, sync and timing tests, and their analysis
peer_coordinator, liblsl_coordinator, webrtc_coordinator	Coordinating experiments across devices (LSL, WebSocket hub, WebRTC)

Getting Started

You're most likely interested in the liblsl package, which is the main package for liblsl.dart. You can find installation instructions and usage examples in the README of that package. API documentation, and the Dart package are available on pub.dev: https://pub.dev/packages/liblsl.

Working with the monorepo

This is a monorepo managed with melos and fvm. To get started, clone this repository including submodules:

git clone --recurse-submodules

Install fvm, then run:

cd liblsl.dart
fvm dart pub get

There are some helpful melos commands for working with the monorepo:

• fvm exec melos run <script>: run a script defined in the melos scripts section of the root pubspec.yaml across all packages. For example, melos run format runs dart format . in all packages.
• fvm exec melos run lint:all: run dart analyze and dart format for all packages, and fail if there are any warnings or formatting issues.
• fvm exec melos run test: run dart test for all packages.

The lint and test scripts at the very least should be run before pushing any changes. For more scripts available, see the pubspec.yaml file.

Contributing

See the CONTRIBUTING.md file for guidelines on how to contribute to this project.

Code of Conduct

This project and everyone participating in it must uphold Code of Conduct. By participating, you are expected to uphold this code.

Support

Please see the SUPPORT.md file for information on how to get support for liblsl.dart and where to ask questions or discuss potential features.

Security

Please see the SECURITY.md file for information on how to report security vulnerabilities for liblsl.dart.

License

This project is licensed under the MIT License - see the LICENSE file for details.