Go Play 2

This is a working Airplay 2 Speaker implementation largely inspired by airplay2-receiver
The goal is to have an Opinionated implementation, with only some features but working very well.

Features

Can

Play AAC 44100Hz with Apple Music (buffered audio)
Play/Pause/Stop/Seek
Homekit pairing with iPhone Home App
Sync with HomePod mini
PTP supported
Working on a Rasbperry 1
Set Volume
Support PulseAudio (and can select sink)

P1 - Improve multi-room support (audio sync)
P2 - Play ALAC
P3 - Supports Spotify (RTP over UDP, type 96)
P4 - NIC hardware timestamp (linux)

Will not support

Windows build
Track information
Screen, Video, ... (other Airplay Features)
Airplay 1
NTP

Multi Room accuracy

The accuracy is around 1ms of offset between clocks.
Need to sync during playing (add silence of skip frames)

How to build ( works on Linux and MacOsX)

Clone the repository

git clone https://github.com/openairplay/goplay2.git

Build goplay2

go build

Dependencies

You need to have portaudio-dev, pulseaudio and lib-fdk-aac and go runtime installed to build this program

Ubuntu 21.4 build

sudo apt install golang-go libfdk-aac-dev

Rasbpian (buster)

fdk-aac is not provided by default, you have to change your source.list (as root or using sudo)

echo "deb http://www.deb-multimedia.org buster main non-free" >> /etc/apt/sources.list
apt-get update -oAcquire::AllowInsecureRepositories=true
apt-get install deb-multimedia-keyring -y
apt-get install libfdk-aac-dev

You also need to install go from https://golang.org/dl/ as version 1.16 is not supplied by buster (they only support 1.11)

Mac os build

Having xcode properly installed (clang needed)

brew install portaudio fdk-aac go

Docker image

You can build the image to test Linux build and that the service run properly

Build the image

docker build -t albanseurat/goplay2:latest .

Run the container

docker run -p 7000:7000 -it albanseurat/goplay2:latest

Acknowledgments

Docker build is intended to test building the program on Linux platform
Bonjour/mDns implementation needs to be changed to allow exposing airplay service outside docker container

Run

goplay2 by default run only on the ipv4 interface (because this issue on ipv6 parsing)

Linux

goplay2 should not be run as root to use pulseaudio server
goplay2 need to have special privileges to open PTP port (319,320)

to allow goplay2 to open port below 1024 you need to run

setcap 'cap_net_bind_service=+ep' ./goplay2

nb: should be re-run every time you build goplay2

Parameters

delay (ms) is subtracted from the local "clock"
Ex: It takes around 60ms on my mac to launch the audio stream at the Anchor Time

i (interface) used to listen (by default eth0)

n (name) used as accessory name (Bonjour)

sink (pulse audio sink name) to replace default sink

Example :

./goplay2 -sink alsa_output -i en0 -n aiwa

By AlbanSeurat

mstemen/goplay2