IRL (in real life) OBS scene switcher (and Proxy)

Why?

I needed a small and simple tool which can proxy TCP and UDP connections, like RTMP or SRT live-streams, and can react upon the availability of these streams.

In simple terms:

This tool monitors a live-stream from your camera feed (SRT or RTMP) and when it detects a connect or disconnect it can switch scenes in Open Broadcaster Studio / OBS (https://obsproject.com/).

How?

This is a keep-it-simple portable console application that can run on Windows, Linux, MacOS. It can run natively or in a container. Whatever your infrastructure this should work somehow.

It offers a simple JSON formatted configuration file (config.json) where you define the TCP or UDP ports that you use to deliver RTMP (using TCP) or SRT (using UDP) streams to.

Furthermore you configure the target IP and Port where you want the data to be delivered to as well as a couple of timeouts.

Features

• forward any stream using srt, rtmp, tcp or plain udp protocols to any IP
• IPv4 and IPv6 and mixed scenarios supported (not on macOS currently)
• switch OBS scenes (by using OBS WebSocket) automatically based on simple rules
  • after n seconds (configurable) upon connect
  • when the data rate is at least over a configurable rate in kbit/s or below
• write a file when a successful connection is made (semaphore)

Limitations

Each remote client is mapped to a port of the local server therefore:

• on macOS currently only IPv4 is supported
• The original IP of the client is hidden to the server the packets are forwarded to.
• The number of concurrent clients is limited by the number of available ports in the server running the proxy.

Pre-Requisites

This tool is using the .NET 6.0 framework which can be freely downloaded here: dotnet 6

Configuration

config.json contains the OBS WebSocket configuration and a list of forwarding rules, for instance :

{
  "OBSWebSocketConnection": {
    "OBSWebSocketHost": "localhost",
    "OBSWebSocketPort": 4444,
    "OBSWebSocketPassword": "password",
    "OBSsceneOnConnect": "connected",
    "OBSsceneOnDisconnect": "disconnected",
    "SemaphoreFileWhenConnected": "IRL-Connected.sem"    
  },
  "ProxyConnections": [
    {
      "localPort": 7777,
      "protocol": "srt",
      "forwardHost": "127.0.0.1",
      "forwardPort": 10000,
      "timeOut": 500,
      "switchToConnectedTime": 1000
	  "minimalkBitperSecond": 400
    }  
  ]
}

• OBSWebSocketHost : The hostname/ip adress of the OBS WebSocket server
• OBSWebSocketPort : The port of the OBS WebSocket server as you configured it
• OBSWebSocketPassword : the password of the OBS WebSocket server as you configured it
• OBSsceneOnConnect : the OBS scene to be used when a successful connection is reported
• OBSsceneOnDisconnect : the OBS scene to be used when a disconnect happened
• SemaphoreFileWhenConnected: a file which will be created when a successful connection is made and removed when there is no connection
• localport : The local port the forwarder should listen to.
• localip : An optional local binding IP the forwarder should listen to. If empty or missing, it will listen to ANY_ADDRESS.
• protocol : The protocol to forward. tcp,rtmp,udp or srt
• forwardHost : The ip the traffic will be forwarded to.
• forwardPort : The port the traffic will be forwarded to.
• timeOut : The timeout in milliseconds to detect disconnects - this is the time after the switch to the disconnected OBS scene is made
• switchToConnectedTime : The wait time in milliseconds after a successful connect before switching to the connected OBS scene
• minimalkBitperSecond : The minimum kbit per second (bits not bytes!) of transfer rate to be and stay in the connected OBS scene

running in a container

This software can be run almost on any platform and comes with a Dockerfile in the irl-obs-switcher directory.

You can easily build the docker image yourself by running this inside the irl-obs-switcher directory:

docker build -t irl-obs-switcher .

This will build the image and name it "irl-obs-switcher". The default config.json will be in the /app directory inside the container and can easily be swapped/edited as you like.

Most probably you will want to change the forward hosts and OBS host settings to use the correct mapped ip adress depending on your environment.

make it run

on Windows

Run the irl-obs-switcher file after you installed dotnet 6.

on Linux

Same as on Windows - preferably you use the Docker/Container version.

on macOS

To run this on macOS install dotnet 6 and download a release like on the other operating systems. Unpack the ZIP file and chmod +x the irl-obs-switcher file. Then run it in a terminal.

You can find screenshots showcasing each step in the /documentation/mac-settings/ folder.

configuration of OBS Studio

In the obs-settings folder of there is a .json file which you can import into OBS and get some sample "connected" and "disconnected" scenes. Essentially this looks like this:

connected scene

disconnected scene

larix broadcaster settings

To stream you can use something like Larix Broadcaster on iOS (or any other SRT or RTMP capable software). Be aware that, depending if you are using RTMP (=TCP) or SRT (=UDP) you have to configure all parts properly.

Also, the IP Adress 192.168.178.9 is just an example I was using - apply your host/ip of where the irl-obs-switcher is listening and then forwarding to your OBS.