losc

OSC 1.0 implementation for lua and luajit.

Compatible with lua 5.1 >= 5.4 luajit 2.0 and luajit 2.1.0-beta3

Features

• Implements the complete OSC 1.0 specification.
• Pure lua implementation, no platform dependent libraries.
• Support for extended OSC types.
• Plugin system for transport layers.
• Address pattern matching.
• Scheduled bundle evaluation (plugin dependent).

Installation

luarocks install losc

Or clone this repo and copy the losc directory into your lua project.

Basic usage

local losc = require'losc'
local plugin = require'losc.plugins.udp-socket'

local udp = plugin.new {sendAddr = 'localhost', sendPort = 9000}
local osc = losc.new {plugin = udp}

-- Create a message
local message = osc.new_message {
  address = '/foo/bar',
  types = 'ifsb',
  123, 1.234, 'hi', 'blobdata'
}

-- Send it over UDP
osc:send(message)

Command line utilities

losc provides two command line tools, loscsend/loscrecv that can be used to send and receive OSC data via UDP.

Note that both tools requires lua-socket.

loscsend - Send an OSC message via UDP.

usage: loscsend ip port address [types [args]]
supported types: b, d, f, h, i, s, t
example: loscsend localhost 57120 /test ifs 1 2.3 "hi"

loscrecv - Dump incoming OSC data.

usage: loscsend port
example: loscrecv 9000

API

The API is divided into two parts:

1. Opaque high level API exposed through the losc.lua module.
2. Low level API exposing serialization/deserialization functions and types based on plain lua tables.

The two API:s are decoupled from each other which makes it possible to implement new high level API:s on top of the low level API functions if needed.

Read more about it in the documentation.

Benchmarks

Generated with lua 5.1.5 (using struct) running on a 2.3 GHz Intel i5 processor.

Message pack:
 -> Iterations:  1000
 -> Time:  5.765507 ms
 -> Avg:  0.005765507 ms
 -> Bytes:  48000
Message unpack:
 -> Iterations:  1000
 -> Time:  5.715137 ms
 -> Avg:  0.005715137 ms
 -> Bytes:  48000
Bundle pack:
 -> Iterations:  1000
 -> Time:  15.804163 ms
 -> Avg:  0.015804163 ms
 -> Bytes:  120000
Bundle unpack:
 -> Iterations:  1000
 -> Time:  11.864412 ms
 -> Avg:  0.011864412 ms
 -> Bytes:  120000

Note on performance

The OSC serialization functions are implemented differently depending on the lua interpreter in use and locally available packages. losc will always work out-of-the-box regardless of lua version since lua-struct is a bundled dependency.

To achieve better performance for lua versions < 5.3 it is recommended to install the struct package locally.

License

MIT License

Copyright (c) 2021 David Granström

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.