audio-engine

A headless, networked audio server written in Rust that uses GStreamer to stream and receive audio across devices. Designed for low-latency audio control in distributed home systems like Raspberry Pi clusters, laptops, or PCs.

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Dependencies

• Rust / Cargo
• GStreamer

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Set up

On linux, first install GStreamer

sudo apt-get install libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio gstreamer1.0-tools gstreamer1.0-plugins-base-apps

and if cargo is installed, just run

cargo run

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Current Capabilities

• One-way audio streaming from one device to another
  • Plays all output of one device on another
  • allows for one way microphone pass, but not bidirectional
• Simple Axum-based HTTP server to start sender or receiver on request

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TO-DO

• dicover devices running engine
• play audio locally
• play audio remote (files, streams, etc.)
• mic broadcast / sending
• spotify

How to use

There are 5 end points:

• send which takes as input the source (pulsesrc for example), device (can be found with pactl list sources short) a host to send audio to and a port. Returns a success message and session_id which is needed to terminate the pipe if needed.
  • request body example: {"source":"pulsesrc","device":"alsa_output.pci-0000_00_1f.3.analog-stereo.monitor","host":"192.168.1.69","port":"5004"}
  • return example: {"host":"192.168.1.69","port":"5004","status":"success","session_id":"e6ad85f3-391f-4d60-b883-7172324deab5"}
• receive which takes as input just the port (the same as the one used on a send request). Returns a success message and session_id which is needed to terminate the pipe if needed.
  • request body example: {"port":"5004"}
  • return example: {"status":"success","session_id":"149bcfbe-cdf0-41b8-afc6-86704d04d1da"}
• stop_send which takes as input the session id, and then terminates the send session. Returns a success message if ok.
  • request body example: {"session_id":"e6ad85f3-391f-4d60-b883-7172324deab5"}
  • return example: {"status":"success","session_id":null"}
• stop_receive which takes as input the session id, and then terminates the send session. Returns a success message if ok.
  • request body example: {"session_id":"149bcfbe-cdf0-41b8-afc6-86704d04d1da"}
  • return example: {"status":"success","session_id":null"}
• fetch_sendable_devices which will return a list of audio devices that a source device can use to send audio thru the stream, this will include microphone inputs, full desktop audio outputs and any other such sources.
  • It is a get request so no body
  • return example: {"device_list":[{"source":"pulsesrc","device":"alsa_output.pci-0000_00_1f.3.analog-stereo.monitor"},{"source":"pulsesrc","device":"alsa_input.pci-0000_00_1f.3.analog-stereo"},{"source":"pulsesink","device":"alsa_output.pci-0000_00_1f.3.analog-stereo"}]}

If running an intance, can use curl to send requests, for example:

curl -H 'Content-Type: application/json' -d '{"port":"5004"}' -X POST 127.0.0.1:3000/receive
curl -H 'Content-Type: application/json' -d '{"source":"pulsesrc","device":"alsa_output.pci-0000_00_1f.3.analog-stereo.monitor","host":"192.168.1.69","port":"5004"}' -X POST 127.0.0.1:3000/send