UxPlay 1.65: AirPlay-Mirror and AirPlay-Audio server for Linux, macOS, and Unix (now also runs on Windows).

Now developed at the GitHub site https://github.com/FDH2/UxPlay (where all user issues should be posted).

Highlights:

• GPLv3, open source.
• Originally supported only AirPlay Mirror protocol, now has added support for AirPlay Audio-only (Apple Lossless ALAC) streaming from current iOS/iPadOS clients. There is no support for Airplay2 video-streaming protocol, and none is planned.
• macOS computers (2011 or later, both Intel and "Apple Silicon" M1/M2 systems) can act either as AirPlay clients, or as the server running UxPlay. Using AirPlay, UxPlay can emulate a second display for macOS clients.
• Support for older iOS clients (such as 32-bit iPad 2nd gen., iPod Touch 5th gen. and iPhone 4S, when upgraded to iOS 9.3.5, or later 64-bit devices), plus a Windows AirPlay-client emulator, AirMyPC.
• Uses GStreamer plugins for audio and video rendering (with options to select different hardware-appropriate output "videosinks" and "audiosinks", and a fully-user-configurable video streaming pipeline).
• Support for server behind a firewall.
• Raspberry Pi support both with and without hardware video decoding by the Broadcom GPU. Tested on Raspberry Pi 4 Model B and Pi 3 model B+.
• Support for running on Microsoft Windows (builds with the MinGW-64 compiler in the unix-like MSYS2 environment).

Packaging status (Linux and *BSD distributions)

.

• Install uxplay on Debian-based Linux systems with "sudo apt install uxplay"; on FreeBSD with "sudo pkg install uxplay". Also available on Arch-based systems through AUR.

• On Linux and *BSD the mDNS/DNS-SD (Bonjour/ZeroConf) local network services needed by UxPlay are usually provided by Avahi: if there is a firewall on the server that will host UxPlay, make sure the default network port for mDNS queries (UDP 5353) is open. (Uxplay can work without this port by using only the host's loopback interface, but its visibility to clients will be degraded.) See the Troubleshooting section below for more details. (With a firewall, you also need to open ports for UxPlay, and use the -p <n> option; see man uxplay or uxplay -h.)

• Even if you install your distribution's pre-compiled uxplay binary package, you may need to read the instructions below for running UxPlay to see which of your distribution's GStreamer plugin packages you should also install.

• For hardware-accelerated video decoding on Raspberry Pi, Ubuntu < 23.04 needs GStreamer to be patched (recommended but optional for Raspberry Pi OS (Bullseye), no longer needed for Manjaro >= 23.02). (Only these three distributions supply a kernel module maintained by Raspberry Pi outside the mainline Linux kernel that accesses the firmware decoder in the Broadcom GPU).

• To (easily) compile the latest UxPlay from source, see the section Getting UxPlay.

Detailed description of UxPlay

This project is a GPLv3 open source unix AirPlay2 Mirror server for Linux, macOS, and *BSD. It was initially developed by antimof using code from OpenMAX-based RPiPlay, which in turn derives from AirplayServer, shairplay, and playfair. (The antimof site is no longer involved in development, but periodically posts updates pulled from the new main UxPlay site).

UxPlay is tested on a number of systems, including (among others) Debian (10 "Buster", 11 "Bullseye", 12 "Bookworm"), Ubuntu (20.04 LTS, 22.04 LTS, 23.04; also Ubuntu derivatives Linux Mint 20.3, Pop!_OS 22.04 (NVIDIA edition)), Red Hat and clones (Fedora 38, Rocky Linux 9.2), OpenSUSE 15.4, Arch Linux 23.05, macOS 13.3 (Intel and M2), FreeBSD 13.2, Windows 10 and 11 (64 bit).

On Raspberry Pi 4 model B, it is tested on Raspberry Pi OS (Bullseye) (32- and 64-bit), Ubuntu 22.04 LTS and 23.04, Manjaro RPi4 23.02, and (without hardware video decoding) on OpenSUSE 15.4. Also tested on Raspberry Pi 3 model B+.

Its main use is to act like an AppleTV for screen-mirroring (with audio) of iOS/iPadOS/macOS clients (iPhone, iPod Touch, iPad, Mac computers) on the server display of a host running Linux, macOS, or other unix (and now also Microsoft Windows). UxPlay supports Apple's AirPlay2 protocol using "Legacy Protocol", but some features are missing. (Details of what is publicly known about Apple's AirPlay 2 protocol can be found here, here and here; see also pyatv which could be a resource for adding modern protocols.) While there is no guarantee that future iOS releases will keep supporting "Legacy Protocol", the recent iOS 16 release continues support.

The UxPlay server and its client must be on the same local area network, on which a Bonjour/Zeroconf mDNS/DNS-SD server is also running (only DNS-SD "Service Discovery" service is strictly necessary, it is not necessary that the local network also be of the ".local" mDNS-based type). On Linux and BSD Unix servers, this is usually provided by Avahi, through the avahi-daemon service, and is included in most Linux distributions (this service can also be provided by macOS, iOS or Windows servers).

Connections to the UxPlay server by iOS/MacOS clients can be initiated both in AirPlay Mirror mode (which streams lossily-compressed AAC audio while mirroring the client screen, or in the alternative AirPlay Audio mode which streams Apple Lossless (ALAC) audio without screen mirroring. In Audio mode, metadata is displayed in the uxplay terminal; if UxPlay option -ca <name> is used, the accompanying cover art is also output to a periodically-updated file <name>, and can be viewed with a (reloading) graphics viewer of your choice. Switching between Mirror and Audio modes during an active connection is possible: in Mirror mode, stop mirroring (or close the mirror window) and start an Audio mode connection, switch back by initiating a Mirror mode connection; cover-art display stops/restarts as you leave/re-enter Audio mode.

• Note that Apple video-DRM (as found in "Apple TV app" content on the client) cannot be decrypted by UxPlay, and the Apple TV app cannot be watched using UxPlay's AirPlay Mirror mode (only the unprotected audio will be streamed, in AAC format), but both video and audio content from DRM-free apps like "YouTube app" will be streamed by UxPlay in Mirror mode.

• As UxPlay does not support non-Mirror AirPlay2 video streaming (where the client controls a web server on the AirPlay server that directly receives content to avoid it being decoded and re-encoded by the client), using the icon for AirPlay video in apps such as the YouTube app will only send audio (in lossless ALAC format) without the accompanying video.

Possibility for using hardware-accelerated h264 video-decoding, if available.

UxPlay uses GStreamer "plugins" for rendering audio and video. This means that video and audio are supported "out of the box", using a choice of plugins. AirPlay streams video in h264 format: gstreamer decoding is plugin agnostic, and uses accelerated GPU hardware h264 decoders if available; if not, software decoding is used.

• VAAPI for Intel and AMD integrated graphics, NVIDIA with "Nouveau" open-source driver

  With an Intel or AMD GPU, hardware decoding with the open-source VAAPI gstreamer plugin is preferable. The open-source "Nouveau" drivers for NVIDIA graphics are also in principle supported: see here, but this requires VAAPI to be supplemented with firmware extracted from the proprietary NVIDIA drivers.

• NVIDIA with proprietary drivers

  The nvh264dec plugin (included in gstreamer1.0-plugins-bad since GStreamer-1.18.0) can be used for accelerated video decoding on the NVIDIA GPU after NVIDIA's CUDA driver libcuda.so is installed. (This plugin should be used with options uxplay -vd nvh264dec -vs glimagesink.) For GStreamer-1.16.3 or earlier, replace nvh264dec by the older plugin nvdec, which must be built by the user: See these instructions.

• Video4Linux2 support for the Raspberry Pi Broadcom 2835 GPU

  Raspberry Pi (RPi) computers (tested on Pi 4 Model B) can now run UxPlay using software video decoding, but hardware-accelerated decoding by firmware in the Pi's GPU is prefered. UxPlay accesses this using the GStreamer-1.22 Video4Linux2 (v4l2) plugin; the plugin from older GStreamer needs a patch to backport fixes from v1.22 (already applied in Raspberry Pi OS (Bullseye), and available for 1.18.4 and later in the UxPlay Wiki). Also requires the out-of-mainline Linux kernel module bcm2835-codec maintained by Raspberry Pi, so far only included in Raspberry Pi OS, and two other distributions (Ubuntu, Manjaro) available with Raspberry Pi Imager.

Note to packagers:

UxPlay's GPLv3 license does not have an added "GPL exception" explicitly allowing it to be distributed in compiled form when linked to OpenSSL versions prior to v. 3.0.0 (older versions of OpenSSL have a license clause incompatible with the GPL unless OpenSSL can be regarded as a "System Library", which it is in *BSD). Many Linux distributions treat OpenSSL as a "System Library", but some (e.g. Debian) do not: in this case, the issue is solved by linking with OpenSSL-3.0.0 or later.

Getting UxPlay

Either download and unzip UxPlay-master.zip, or (if git is installed): "git clone https://github.com/FDH2/UxPlay". You can also download a recent or earlier version listed in Releases.

• A recent UxPlay can also be found on the original antimof site; that original project is inactive, but is usually kept current or almost-current with the active UxPlay github site (thank you antimof!).

Building UxPlay on Linux (or *BSD):

Debian-based systems:

(Adapt these instructions for non-Debian-based Linuxes or *BSD; for macOS, see specific instruction below). See Troubleshooting below for help with any difficulties.

You need a C/C++ compiler (e.g. g++) with the standard development libraries installed. Debian-based systems provide a package "build-essential" for use in compiling software. You also need pkg-config: if it is not found by "which pkg-config", install pkg-config or its work-alike replacement pkgconf. Also make sure that cmake>=3.4.1 is installed: "sudo apt-get install cmake" (add build-essential and pkg-config (or pkgconf) to this if needed).

Make sure that your distribution provides OpenSSL 1.1.1 or later, and libplist 2.0 or later. (This means Debian 10 "Buster" based systems (e.g, Ubuntu 18.04) or newer; on Debian 10 systems "libplist" is an older version, you need "libplist3".) If it does not, you may need to build and install these from source (see instructions at the end of this README). If you have a non-standard OpenSSL installation, you may need to set the environment variable OPENSSL_ROOT_DIR (e.g. , "export OPENSSL_ROOT_DIR=/usr/local/lib64" if that is where it is installed).

In a terminal window, change directories to the source directory of the downloaded source code ("UxPlay-*", "*" = "master" or the release tag for zipfile downloads, "UxPlay" for "git clone" downloads), then follow the instructions below:

Note: By default UxPlay will be built with optimization for the computer it is built on; when this is not the case, as when you are packaging for a distribution, use the cmake option -DNO_MARCH_NATIVE=ON.

If you use X11 Windows on Linux or *BSD, and wish to toggle in/out of fullscreen mode with a keypress (F11 or Alt_L+Enter) UxPlay needs to be built with a dependence on X11. Starting with UxPlay-1.59, this will be done by default IF the X11 development libraries are installed and detected. Install these with "sudo apt-get install libx11-dev". If GStreamer < 1.20 is detected, a fix needed by screen-sharing apps (e.g., Zoom) will also be made.

• If X11 development libraries are present, but you wish to build UxPlay without any X11 dependence, use the cmake option -DNO_X11_DEPS=ON.

1. sudo apt-get install libssl-dev libplist-dev". (unless you need to build OpenSSL and libplist from source).
2. sudo apt-get install libavahi-compat-libdnssd-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev.
3. cmake . (For a cleaner build, which is useful if you modify the source, replace this by "mkdir build; cd build; cmake ..": you can then delete the build directory if needed, without affecting the source.) Also add any cmake "-D" options here as needed (e.g, -DNO_X11_DEPS=ON or -DNO_MARCH_NATIVE=ON).
4. make
5. sudo make install (you can afterwards uninstall with sudo make uninstall in the same directory in which this was run).

The above script installs the executable file "uxplay" to /usr/local/bin, (and installs a manpage to somewhere like /usr/local/share/man/man1 and README files to somewhere like /usr/local/share/doc/uxplay). The uxplay executable can also be found in the build directory after the build process, if you wish to test before installing (in which case the GStreamer plugins must already be installed)

Building on non-Debian Linux and *BSD

• Red Hat, or clones like CentOS (now continued as Rocky Linux or Alma Linux): (sudo dnf install, or sudo yum install) openssl-devel libplist-devel avahi-compat-libdns_sd-devel gstreamer1-devel gstreamer1-plugins-base-devel (+libX11-devel for fullscreen X11) (some of these may be in the "CodeReady" add-on repository, called "PowerTools" by clones)

• OpenSUSE: (sudo zypper install) libopenssl-devel libplist-2_0-devel (formerly libplist-devel) avahi-compat-mDNSResponder-devel gstreamer-devel gstreamer-plugins-base-devel (+ libX11-devel for fullscreen X11).

• Arch Linux (Also available as a package in AUR): (sudo pacman -Syu) openssl libplist avahi gst-plugins-base.

• FreeBSD: (sudo pkg install) libplist gstreamer1. Either avahi-libdns or mDNSResponder must also be installed to provide the dns_sd library. OpenSSL is already installed as a System Library.

Running UxPlay

Installing plugins (Debian-based Linux systems)

Next install the GStreamer plugins that are needed with sudo apt-get install gstreamer1.0-<plugin>. Values of <plugin> required are:

1. "plugins-base"
2. "libav" (for sound),
3. "plugins-good" (for v4l2 hardware h264 decoding)
4. "plugins-bad" (for h264 decoding).

Plugins that may also be needed include "gl" for OpenGL support (which may be useful, and should be used with h264 decoding by the NVIDIA GPU), and "x" for X11 support, although these may already be installed; "vaapi" is needed for hardware-accelerated h264 video decoding by Intel or AMD graphics (but not for use with NVIDIA using proprietary drivers). If sound is not working, "alsa"", "pulseaudio", or "pipewire" plugins may need to be installed, depending on how your audio is set up.

• Also install "gstreamer1.0-tools" to get the utility gst-inspect-1.0 for examining the GStreamer installation.

Installing plugins (Non-Debian-based Linux or *BSD)

• Red Hat, or clones like CentOS (now continued as Rocky Linux or Alma Linux): (sudo dnf install, or sudo yum install) gstreamer1-libav gstreamer1-plugins-bad-free (+ gstreamer1-vaapi for Intel/AMD graphics). You may need to get some of them (in particular gstreamer1-libav) from rpmfusion.org (which provides packages including plugins that RedHat does not ship for license reasons). [In recent Fedora, the libav plugin package is renamed to "gstreamer1-plugin-libav", which now needs the RPM Fusion package ffmpeg-libs for the patent-encumbered code which RedHat does not provide: check with "rpm -qi ffmpeg-libs" that it lists "Packager" as RPM Fusion; if this is not installed, uxplay will fail to start, with error: no element "avdec_aac" ].

• OpenSUSE: (sudo zypper install) gstreamer-plugins-libav gstreamer-plugins-bad (+ gstreamer-plugins-vaapi for Intel/AMD graphics). In some cases, you may need to use gstreamer or libav* packages for OpenSUSE from Packman "Essentials" (which provides packages including plugins that OpenSUSE does not ship for license reasons; recommendation: after adding the Packman repository, use the option in YaST Software management to switch all system packages for multimedia to Packman).

• Arch Linux (sudo pacman -Syu) gst-plugins-good gst-plugins-bad gst-libav (+ gstreamer-vaapi for Intel/AMD graphics).

• FreeBSD: (sudo pkg install) gstreamer1-libav, gstreamer1-plugins, gstreamer1-plugins-* (* = core, good, bad, x, gtk, gl, vulkan, pulse, v4l2, ...), (+ gstreamer1-vaapi for Intel/AMD graphics).

Starting and running UxPlay

Since UxPlay-1.64, UxPlay can be started with options read from a configuration file, which will be the first found of (1) a file with a path given by environment variable $UXPLAYRC, (2) ~/.uxplayrc in the user's home directory ("~"), (3) ~/.config/uxplayrc. The format is one option per line, omitting the initial "-" of the command-line option. Lines in the configuration file beginning with "#" are treated as comments and ignored.

Run uxplay in a terminal window. On some systems, you can toggle into and out of fullscreen mode with F11 or (held-down left Alt)+Enter keys. Use Ctrl-C (or close the window) to terminate it when done. If the UxPlay server is not seen by the iOS client's drop-down "Screen Mirroring" panel, check that your DNS-SD server (usually avahi-daemon) is running: do this in a terminal window with systemctl status avahi-daemon. If this shows the avahi-daemon is not running, control it with sudo systemctl [start,stop,enable,disable] avahi-daemon (on non-systemd systems, such as *BSD, use sudo service avahi-daemon [status, start, stop, restart, ...]). If UxPlay is seen, but the client fails to connect when it is selected, there may be a firewall on the server that prevents UxPlay from receiving client connection requests unless some network ports are opened: if a firewall is active, also open UDP port 5353 (for mDNS queries) needed by Avahi. See Troubleshooting below for help with this or other problems.

• By default, UxPlay is locked to its current client until that client drops the connection; since UxPlay-1.58, the option -nohold modifies this behavior so that when a new client requests a connection, it removes the current client and takes over.

• In Mirror mode, GStreamer has a choice of two methods to play video with its accompanying audio: prior to UxPlay-1.64, the video and audio streams were both played as soon as possible after they arrived (the GStreamer "sync=false" method), with a GStreamer internal clock used to try to keep them synchronized. Starting with UxPlay-1.64, the other method (GStreamer's "sync=true" mode), which uses timestamps in the audio and video streams sent by the client, is the new default. On low-decoding-power UxPlay hosts (such as Raspberry Pi 3 models) this will drop video frames that cannot be decoded in time to play with the audio, making the video jerky, but still synchronized.

The older method which does not drop late video frames worked well on more powerful systems, and is still available with the UxPlay option "-vsync no"; this method is adapted to "live streaming", and may be better when using UxPlay as a second monitor for a Mac computer, for example, while the new default timestamp-based method is best for watching a video, to keep lip movements and voices synchronized. (Without use of timestamps, video will eventually lag behind audio if it cannot be decoded fast enough: hardware-accelerated video-decoding helped to prevent this previously when timestamps were not being used.)

• In Audio-only mode the GStreamer "sync=false" mode (not using timestamps) is still the default, but if you want to keep the audio playing on the server synchronized with the video showing on the client, use the -async timestamp-based option. (An example might be if you want to follow the Apple Music lyrics on the client while listening to superior sound on the UxPlay server). This delays the video on the client to match audio on the server, so leads to a slight delay before a pause or track-change initiated on the client takes effect on the audio played by the server.

The -vsync and -async options also allow an optional positive (or negative) audio-delay adjustment in milliseconds for fine-tuning : -vsync 20.5 delays audio relative to video by 0.0205 secs; a negative value advances it.)

• you may find video is improved by the setting -fps 60 that allows some video to be played at 60 frames per second. (You can see what framerate is actually streaming by using -vs fpsdisplaysink, and/or -FPSdata.) When using this, you should use the default timestamp-based synchronization option -vsync.

• Since UxPlay-1.54, you can display the accompanying "Cover Art" from sources like Apple Music in Audio-Only (ALAC) mode: run "uxplay -ca <name> &" in the background, then run a image viewer with an autoreload feature: an example is "feh": run "feh -R 1 <name>" in the foreground; terminate feh and then Uxplay with "ctrl-C fg ctrl-C".

One common problem involves GStreamer attempting to use incorrectly-configured or absent accelerated hardware h264 video decoding (e.g., VAAPI). Try "uxplay -avdec" to force software video decoding; if this works you can then try to fix accelerated hardware video decoding if you need it, or just uninstall the GStreamer VAAPI plugin. If your system uses the Wayland compositor for graphics, use "uxplay -vs waylandsink". See Usage for more run-time options.

Special instructions for Raspberry Pi (tested on R Pi 4 model B 8GB and R Pi 3 model B+):

• If you use the software-only (h264) video-decoding UxPlay option -avdec, it now works better than earlier, with the new default timestamp-based synchronization to keep audio and video synchronized.

• For best performance, the Raspberry Pi needs the GStreamer Video4linux2 plugin to use its Broadcom GPU hardware for decoding h264 video. This needs the bcm2835_codec kernel module which is maintained oustide the mainline Linux kernel by Raspberry Pi in the the Raspberry Pi kernel tree, and the only distributions for R Pi that are known to supply it include Raspberry Pi OS, Ubuntu, and Manjaro (all available from Raspberry Pi with their Raspberry Pi Imager). Other distributions generally do not provide it: without this kernel module, UxPlay cannot use the decoding firmware in the GPU.

For use of the GPU, use raspi-config "Performance Options" (on Raspberry Pi OS, use a similar tool on other distributions) to allocate sufficient memory for the GPU (on R. Pi 3 model B+, the maximum (256MB) is suggested). Even with GPU video decoding, some frames may be dropped by the lower-power 3 B+ to keep audio and video synchronized using timestamps.

• The plugin in the latest GStreamer-1.22 release works well, but older releases of GStreamer will not work unless patched with backports from GStreamer-1.22. Raspberry Pi OS (Bullseye) now has a working backport. For a fuller backport, or for other distributions, patches for the GStreamer Video4Linux2 plugin are available with instructions in the UxPlay Wiki.

The basic uxplay options for R Pi are uxplay [-vs <videosink>]. The choice <videosink> = glimagesink is sometimes useful. On a system without X11 (like R Pi OS Lite) with framebuffer video, use <videosink> = kmssink. With the Wayland video compositor, use <videosink> = waylandsink. When using the Video4Linux2 plugin to access hardware video decoding, an option -v4l2 may be useful: for convenience, this also comes combined with various videosink options as -rpi, -rpigl -rpifb, -rpiwl, respectively provided for X11, X11 with OpenGL, framebuffer, and Wayland systems. You may find that just "uxplay", (without -v4l2 or -rpi* options, which lets GStreamer try to find the best video solution by itself) provides the best results (the -rpi* options may be removed in a future release of UxPlay.)

• If you are using Raspberry Pi OS (Bullseye) with Video4Linux2 from unpatched GStreamer-1.18.4, you need the -bt709 option with UxPlay-1.56 or later. Also don't use options -v4l2 and -rpi* with it, as they cause a crash if the client screen is rotated. (These issues do not occur when the latest GStreamer-1.18.4 patch from the UxPlay Wiki has been applied.)

• Tip: to start UxPlay on a remote host (such as a Raspberry Pi) using ssh:

   ssh user@remote_host
   export DISPLAY=:0
   nohup uxplay [options] > FILE &

Sound and video will play on the remote host; "nohup" will keep uxplay running if the ssh session is closed. Terminal output is saved to FILE (which can be /dev/null to discard it)

Building UxPlay on macOS: (Intel X86_64 and "Apple Silicon" M1/M2 Macs)

Note: A native AirPlay Server feature is included in macOS 12 Monterey, but is restricted to recent hardware. UxPlay can run on older macOS systems that will not be able to run Monterey, or can run Monterey but not AirPlay.

These instructions for macOS assume that the Xcode command-line developer tools are installed (if Xcode is installed, open the Terminal, type "sudo xcode-select --install" and accept the conditions).

It is also assumed that CMake >= 3.13 is installed: this can be done with package managers MacPorts (sudo port install cmake), Homebrew (brew install cmake), or by a download from https://cmake.org/download/. Also install git if you will use it to fetch UxPlay.

Next install libplist and openssl-3.x. Note that static versions of these libraries will be used in the macOS builds, so they can be uninstalled after building uxplay, if you wish.

• If you use Homebrew: brew install libplist openssl@3

• if you use MacPorts: sudo port install libplist-devel openssl3

Otherwise, build libplist and openssl from source: see instructions near the end of this README; requires development tools (autoconf, automake, libtool, etc.) to be installed.

Next get the latest macOS release of GStreamer-1.0.

Using "Official" GStreamer (Recommended for both MacPorts and Homebrew users): install the GStreamer release for macOS from https://gstreamer.freedesktop.org/download/. (This release contains its own pkg-config, so you don't have to install one.) Install both the gstreamer-1.0 and gstreamer-1.0-devel packages. After downloading, Shift-Click on them to install (they install to /Library/FrameWorks/GStreamer.framework). Homebrew or MacPorts users should not install (or should uninstall) the GStreamer supplied by their package manager, if they use the "official" release.

• ADDED 2023-01-25: in the latest release (now 1.22.2) something in the GStreamer macOS binaries appears to not be working (UxPlay starts receiving the AirPlay stream, but the video window does not open). If you have this problem, use the GStreamer-1.20.6 binary packages until a fix is found. You could instead compile the "official" GStreamer-1.22.x release from source: GStreamer-1.22.0 has been successfully built this way on a system using MacPorts: see the UxPlay Wiki.

Using Homebrew's GStreamer: pkg-config is needed: ("brew install pkg-config gstreamer"). This causes a large number of extra packages to be installed by Homebrew as dependencies. The Homebrew gstreamer installation has recently been reworked into a single "formula" named gstreamer, which now works without needing GST_PLUGIN_PATH to be set in the enviroment. Homebrew installs gstreamer to (HOMEBREW)/lib/gstreamer-1.0 where (HOMEBREW)/* is /opt/homebrew/* on Apple Silicon Macs, and /usr/local/* on Intel Macs; do not put any extra non-Homebrew plugins (that you build yourself) there, and instead set GST_PLUGIN_PATH to point to their location (Homebrew does not supply a complete GStreamer, but seems to have everything needed for UxPlay).

Finally, build and install uxplay: open a terminal and change into the UxPlay source directory ("UxPlay-master" for zipfile downloads, "UxPlay" for "git clone" downloads) and build/install with "cmake . ; make ; sudo make install " (same as for Linux).

• Running UxPlay while checking for GStreamer warnings (do this with "export GST_DEBUG=2" before runnng UxPlay) reveals that with the default (since UxPlay 1.64) use of timestamps for video synchonization, many video frames are being dropped (only on macOS), perhaps due to another error (about videometa) that shows up in the GStreamer warnings. Recommendation: use the new UxPlay "no timestamp" option "-vsync no" (you can add a line "vsync no" in the uxplayrc configuration file).

• On macOS with this installation of GStreamer, the only videosinks available seem to be glimagesink (default choice made by autovideosink) and osxvideosink. The window title does not show the Airplay server name, but the window is visible to screen-sharing apps (e.g., Zoom). The only available audiosink seems to be osxaudiosink.

• The option -nc is always used, whether or not it is selected. This is a workaround for a problem with GStreamer videosinks on macOS: if the GStreamer pipeline is destroyed while the mirror window is still open, a segfault occurs.

• In the case of glimagesink, the resolution settings "-s wxh" do not affect the (small) initial OpenGL mirror window size, but the window can be expanded using the mouse or trackpad. In contrast, a window created with "-vs osxvideosink" is initially big, but has the wrong aspect ratio (stretched image); in this case the aspect ratio changes when the window width is changed by dragging its side; the option "-vs osxvideosink force-aspect-ratio=true" can be used to make the window have the correct aspect ratio when it first opens.

Using GStreamer installed from MacPorts (not recommended):

To install: "sudo port install pkgconf"; "sudo port install gstreamer1-gst-plugins-base gstreamer1-gst-plugins-good gstreamer1-gst-plugins-bad gstreamer1-gst-libav". The MacPorts GStreamer is old (v1.16.2) and built to use X11: use the special CMake option -DUSE_X11=ON when building UxPlay. Then uxplay must be run from an XQuartz terminal, and needs option "-vs ximagesink". On a unibody (non-retina) MacBook Pro, the default resolution wxh = 1920x1080 was too large, but using option "-s 800x600" worked. The MacPorts GStreamer pipeline seems fragile against attempts to change the X11 window size, or to rotations that switch a connected client between portrait and landscape mode while uxplay is running. Using the MacPorts X11 GStreamer seems only possible if the image size is left unchanged from the initial "-s wxh" setting (also use the iPad/iPhone setting that locks the screen orientation against switching between portrait and landscape mode as the device is rotated).

Building UxPlay on Microsoft Windows, using MSYS2 with the MinGW-64 compiler.

• tested on Windows 10 and 11, 64-bit.

1. Download and install Bonjour SDK for Windows v3.0 from the official Apple site https://developer.apple.com/download

2. (This is for 64-bit Windows; a build for 32-bit Windows should be possible, but is not tested.) The unix-like MSYS2 build environment will be used: download and install MSYS2 from the official site https://www.msys2.org/. Accept the default installation location C:\mysys64.

3. Next update MSYS2 and install the MinGW-64 compiler and cmake (MSYS2 packages are installed with a variant of the "pacman" package manager used by Arch Linux). Open a MSYS2 MinGW x64 terminal from the MSYS2 64 bit tab in the Windows Start menu, then run

   pacman -Syu mingw-w64-x86_64-cmake mingw-w64-x86_64-gcc
   

   The compiler with all required dependencies will be installed in the msys64 directory, with default path C:/msys64/mingw64. Here we will simply build UxPlay from the command line in the MSYS2 environment (this uses "ninja" in place of "make" for the build system).

4. Download the latest UxPlay from github (to use git, install it with pacman -S git, then "git clone https://github.com/FDH2/UxPlay"), then install UxPlay dependencies (openssl is already installed with MSYS2):

   pacman -S mingw-w64-x86_64-libplist mingw-w64-x86_64-gstreamer mingw-w64-x86_64-gst-plugins-base

   Note that libplist will be linked statically to the uxplay executable. If you are trying a different Windows build system, MSVC versions of GStreamer for Windows are available from the official GStreamer site, but only the MinGW 64-bit build on MSYS2 has been tested.

5. cd to the UxPlay source directory, then "mkdir build" and "cd build", followed by

   cmake ..

   ninja

6. Assuming no error in either of these, you will have built the uxplay executable uxplay.exe in the current ("build") directory. The "sudo make install" and "sudo make uninstall" features offered in the other builds are not available on Windows; instead, the MSYS2 environment has /mingw64/... available, and you can install the uxplay.exe executable in C:/msys64/mingw64/bin (plus manpage and documentation in C:/msys64/mingw64/share/...) with

   cmake --install . --prefix /mingw64

   To be able to view the manpage, you need to install the manpage viewer with "pacman -S man".

To run uxplay.exe you need to install some gstreamer plugin packages with pacman -S mingw-w64-x86_64-gst-<plugin>, where the required ones have <plugin> given by

1. libav
2. plugins-good
3. plugins-bad

Other possible MSYS2 gstreamer plugin packages you might use are listed in MSYS2 packages.

You also will need to grant permission to the uxplay executable uxplay.exe to access data through the Windows firewall. You may automatically be offered the choice to do this when you first run uxplay, or you may need to do it using Windows Settings->Update and Security->Windows Security->Firewall & network protection -> allow an app through firewall. If your virus protection flags uxplay.exe as "suspicious" (but without a true malware signature) you may need to give it an exception.

Now test by running "uxplay" (in a MSYS2 terminal window). If you need to specify the audiosink, there are two main choices on Windows: the older DirectSound plugin "-as directsoundsink", and the more modern Windows Audio Session API (wasapi) plugin "-as wasapisink", which supports additional options such as

uxplay -as 'wasapisink low_latency=true device=\"<guid>\"' 

where <guid> specifies an available audio device by its GUID, which can be found using "gst-device-monitor-1.0 Audio": <guid> has a form like \{0.0.0.00000000\}.\{98e35b2b-8eba-412e-b840-fd2c2492cf44\}. If "device" is not specified, the default audio device is used.

If you wish to specify the videosink using the -vs <videosink> option, some choices for <videosink> are d3d11videosink, d3dvideosink, glimagesink, gtksink. With Direct3D 11.0 or greater, you can get the ability to toggle into and out of fullscreen mode using the Alt-Enter key combination with option -vs "d3d11videosink fullscreen-toggle-mode=alt-enter". For convenience, this option will be added if just -vs d3d11videosink (by itself) is used.

The executable uxplay.exe can also be run without the MSYS2 environment, in the Windows Terminal, with C:\msys64\mingw64\bin\uxplay.

Usage

Options:

-n server_name (Default: UxPlay); server_name@hostname will be the name that appears offering AirPlay services to your iPad, iPhone etc, where hostname is the name of the server running uxplay. This will also now be the name shown above the mirror display (X11) window.

-nh Do not append "@hostname" at the end of the AirPlay server name.

-vsync [x] (In Mirror mode:) this option (now the default) uses timestamps to synchronize audio with video on the server, with an optional audio delay in (decimal) milliseconds (x = "20.5" means 0.0205 seconds delay: positive or negative delays less than a second are allowed.) It is needed on low-power systems such as Raspberry Pi without hardware video decoding.

-vsync no (In Mirror mode:) this switches off timestamp-based audio-video synchronization, restoring the default behavior prior to UxPlay-1.64. Standard desktop systems seem to work well without use of timestamps: this mode is appropriate for "live streaming" such as using UxPlay as a second monitor for a mac computer, or monitoring a webcam; with it, no video frames are dropped.

-async [x] (In Audio-Only (ALAC) mode:) this option uses timestamps to synchronize audio on the server with video on the client, with an optional audio delay in (decimal) milliseconds (x = "20.5" means 0.0205 seconds delay: positive or negative delays less than a second are allowed.) Because the client adds a video delay to account for latency, the server in -async mode adds an equivalent audio delay, which means that audio changes such as a pause or a track-change will not take effect immediately. This might in principle be mitigated by using the -al audio latency setting to change the latency (default 0.25 secs) that the server reports to the client, but at present changing this does not seem to have any effect.

-async no. This is the still the default behavior in Audio-only mode, but this option may be useful as a command-line option to switch off a -async option set in a "uxplayrc" configuration file.

-s wxh (e.g. -s 1920x1080 , which is the default ) sets the display resolution (width and height, in pixels). (This may be a request made to the AirPlay client, and perhaps will not be the final resolution you get.) w and h are whole numbers with four digits or less. Note that the height pixel size is the controlling one used by the client for determining the streaming format; the width is dynamically adjusted to the shape of the image (portrait or landscape format, depending on how an iPad is held, for example).

-s wxh@r As above, but also informs the AirPlay client about the screen refresh rate of the display. Default is r=60 (60 Hz); r must be a whole number less than 256.

-o turns on an "overscanned" option for the display window. This reduces the image resolution by using some of the pixels requested by option -s wxh (or their default values 1920x1080) by adding an empty boundary frame of unused pixels (which would be lost in a full-screen display that overscans, and is not displayed by gstreamer). Recommendation: don't use this option unless there is some special reason to use it.

-fs uses fullscreen mode, but only works with X11, Wayland or VAAPI.

-p allows you to select the network ports used by UxPlay (these need to be opened if the server is behind a firewall). By itself, -p sets "legacy" ports TCP 7100, 7000, 7001, UDP 6000, 6001, 7011. -p n (e.g. -p 35000) sets TCP and UDP ports n, n+1, n+2. -p n1,n2,n3 (comma-separated values) sets each port separately; -p n1,n2 sets ports n1,n2,n2+1. -p tcp n or -p udp n sets just the TCP or UDP ports. Ports must be in the range [1024-65535].

If the -p option is not used, the ports are chosen dynamically (randomly), which will not work if a firewall is running.

-avdec forces use of software h264 decoding using Gstreamer element avdec_h264 (libav h264 decoder). This option should prevent autovideosink choosing a hardware-accelerated videosink plugin such as vaapisink.

-vp parser choses the GStreamer pipeline's h264 parser element, default is h264parse. Using quotes "..." allows options to be added.

-vd decoder chooses the GStreamer pipeline's h264 decoder element, instead of the default value "decodebin" which chooses it for you. Software decoding is done by avdec_h264; various hardware decoders include: vaapih264dec, nvdec, nvh264dec, v4l2h264dec (these require that the appropriate hardware is available). Using quotes "..." allows some parameters to be included with the decoder name.

-vc converter chooses the GStreamer pipeline's videoconverter element, instead of the default value "videoconvert". When using Video4Linux2 hardware-decoding by a GPU,-vc v4l2convert will also use the GPU for video conversion. Using quotes "..." allows some parameters to be included with the converter name.

-vs videosink chooses the GStreamer videosink, instead of the default value "autovideosink" which chooses it for you. Some videosink choices are: ximagesink, xvimagesink, vaapisink (for intel graphics), gtksink, glimagesink, waylandsink, osximagesink (for macOS), kmssink (for systems without X11, like Raspberry Pi OS lite) or fpsdisplaysink (which shows the streaming framerate in fps). Using quotes "..." allows some parameters to be included with the videosink name. For example, fullscreen mode is supported by the vaapisink plugin, and is obtained using -vs "vaapisink fullscreen=true"; this also works with waylandsink. The syntax of such options is specific to a given plugin, and some choices of videosink might not work on your system.

-vs 0 suppresses display of streamed video, but plays streamed audio. (The client's screen is still mirrored at a reduced rate of 1 frame per second, but is not rendered or displayed.) This feature (which streams audio in AAC audio format) is now probably unneeded, as UxPlay can now stream superior-quality Apple Lossless audio without video in Airplay non-mirror mode.

-v4l2 Video settings for hardware h264 video decoding in the GPU by Video4Linux2. Equivalent to -vd v4l2h264dec -vc v4l2convert.

-bt709 A workaround for the failure of the older Video4Linux2 plugin to recognize Apple's use of an uncommon (but permitted) "full-range color" variant of the bt709 color standard for digital TV. This is no longer needed by GStreamer-1.20.4 and backports from it.

-rpi Equivalent to "-v4l2 ". Use for "Desktop" Raspberry Pi systems with X11.

-rpigl Equivalent to "-rpi -vs glimagesink". Sometimes better for "Desktop" Raspberry Pi systems with X11.

-rpifb Equivalent to "-rpi -vs kmssink" (use for Raspberry Pi systems using the framebuffer, like RPi OS Bullseye Lite).

-rpiwl Equivalent to "-rpi -vs waylandsink", for Raspberry Pi "Desktop" systems using the Wayland video compositor (use for Ubuntu 21.10 for Raspberry Pi 4B).

-as audiosink chooses the GStreamer audiosink, instead of letting autoaudiosink pick it for you. Some audiosink choices are: pulsesink, alsasink, pipewiresink, osssink, oss4sink, jackaudiosink, osxaudiosink (for macOS), wasapisink, directsoundsink (for Windows). Using quotes "..." might allow some parameters to be included with the audiosink name. (Some choices of audiosink might not work on your system.)

-as 0 (or just -a) suppresses playing of streamed audio, but displays streamed video.

-al x specifies an audio latency x in (decimal) seconds in Audio-only (ALAC), that is reported to the client. Values in the range [0.0, 10.0] seconds are allowed, and will be converted to a whole number of microseconds. Default is 0.25 sec (250000 usec). (This replaces the -ao option introduced in v1.62, as a workaround for a problem that is now fixed).

-ca filename provides a file (where filename can include a full path) used for output of "cover art" (from Apple Music, etc.,) in audio-only ALAC mode. This file is overwritten with the latest cover art as it arrives. Cover art (jpeg format) is discarded if this option is not used. Use with a image viewer that reloads the image if it changes, or regularly (e.g. once per second.). To achieve this, run "uxplay -ca [path/to/]filename &" in the background, then run the the image viewer in the foreground. Example, using feh as the viewer: run "feh -R 1 [path/to/]filename" (in the same terminal window in which uxplay was put into the background). To quit, use ctrl-C fg ctrl-C to terminate the image viewer, bring uxplay into the foreground, and terminate it too.

-reset n sets a limit of n consecutive timeout failures of the client to respond to ntp requests from the server (these are sent every 3 seconds to check if the client is still present, and synchronize with it). After n failures, the client will be presumed to be offline, and the connection will be reset to allow a new connection. The default value of n is 5; the value n = 0 means "no limit" on timeouts.

-nc maintains previous UxPlay < 1.45 behavior that does not close the video window when the the client sends the "Stop Mirroring" signal. This option is currently used by default in macOS, as the window created in macOS by GStreamer does not terminate correctly (it causes a segfault) if it is still open when the GStreamer pipeline is closed.

-nohold Drops the current connection when a new client attempts to connect. Without this option, the current client maintains exclusive ownership of UxPlay until it disconnects.

-FPSdata Turns on monitoring of regular reports about video streaming performance that are sent by the client. These will be displayed in the terminal window if this option is used. The data is updated by the client at 1 second intervals.

-fps n sets a maximum frame rate (in frames per second) for the AirPlay client to stream video; n must be a whole number less than 256. (The client may choose to serve video at any frame rate lower than this; default is 30 fps.) A setting of 60 fps may give you improved video but is not recommended on Raspberry Pi. A setting below 30 fps might be useful to reduce latency if you are running more than one instance of uxplay at the same time. This setting is only an advisory to the client device, so setting a high value will not force a high framerate. (You can test using "-vs fpsdisplaysink" to see what framerate is being received, or use the option -FPSdata which displays video-stream performance data continuously sent by the client during video-streaming.)

-f {H|V|I} implements "videoflip" image transforms: H = horizontal flip (right-left flip, or mirror image); V = vertical flip ; I = 180 degree rotation or inversion (which is the combination of H with V).

-r {R|L} 90 degree Right (clockwise) or Left (counter-clockwise) rotations; these image transforms are carried out after any -f transforms.

-m generates a random MAC address to use instead of the true hardware MAC number of the computer's network card. (Different server_name, MAC addresses, and network ports are needed for each running uxplay if you attempt to run two instances of uxplay on the same computer.) If UxPlay fails to find the true MAC address of a network card, (more specifically, the MAC address used by the first active network interface detected) a random MAC address will be used even if option -m was not specified. (Note that a random MAC address will be different each time UxPlay is started).

-t timeout [This option was removed in UxPlay v.1.61.]

-vdmp Dumps h264 video to file videodump.h264. -vdmp n dumps not more than n NAL units to videodump.x.h264; x= 1,2,... increases each time a SPS/PPS NAL unit arrives. To change the name videodump, use -vdmp [n] filename.

-admp Dumps audio to file audiodump.x.aac (AAC-ELD format audio), audiodump.x.alac (ALAC format audio) or audiodump.x.aud (other-format audio), where x = 1,2,3... increases each time the audio format changes. -admp n restricts the number of packets dumped to a file to n or less. To change the name audiodump, use -admp [n] filename. Note that (unlike dumped video) the dumped audio is currently only useful for debugging, as it is not containerized to make it playable with standard audio players.

-d Enable debug output. Note: this does not show GStreamer error or debug messages. To see GStreamer error and warning messages, set the environment variable GST_DEBUG with "export GST_DEBUG=2" before running uxplay. To see GStreamer information messages, set GST_DEBUG=4; for DEBUG messages, GST_DEBUG=5; increase this to see even more of the GStreamer inner workings.

Troubleshooting

Note: uxplay is run from a terminal command line, and informational messages are written to the terminal.

0. Problems in compiling UxPlay.

One user (on Ubuntu) found compilation failed with messages about linking to "usr/local/lib/libcrypto.a" and "zlib". This was because (in addition to the standard ubuntu installation of libssl-dev), the user was unaware that a second installation with libcrypto in /usr/local was present. Solution: when more than one installation of OpenSSL is present, set the environment variable OPEN_SSL_ROOT_DIR to point to the correct one; on 64-bit Ubuntu, this is done by running export OPENSSL_ROOT_DIR=/usr/lib/X86_64-linux-gnu/ before running cmake.

1. Avahi/DNS_SD Bonjour/Zeroconf issues

The DNS_SD Service-Discovery ("Bonjour" or "Zeroconf") service is required for UxPlay to work. On Linux, it will be usually provided by Avahi, and to troubleshoot this, you should use the tool avahi-browse. (You may need to install a separate package with a name like avahi-utils to get this.)

On Linux, make sure Avahi is installed, and start the avahi-daemon service on the system running uxplay (your distribution will document how to do this, for example: sudo systemctl <cmd> avahi-daemon or sudo service avahi-daemon <cmd>, with <cmd> one of enable, disable, start, stop, status. You might need to edit the avahi-daemon.conf file (it is typically in /etc/avahi/, find it with "sudo find /etc -name avahi-daemon.conf"): make sure that "disable-publishing" is not a selected option). Some systems may instead use the mdnsd daemon as an alternative to provide DNS-SD service. (FreeBSD offers both alternatives, but only Avahi was tested; see here.)

• uxplay starts, but either stalls or stops after "Initialized server socket(s)" appears (without the server name showing on the client).

If UxPlay stops with the "No DNS-SD Server found" message, this means that your network does not have a running Bonjour/zeroconf DNS-SD server. Before v1.60, UxPlay used to stall silently if DNS-SD service registration failed, but now stops with an error message returned by the DNSServiceRegister function: kDNSServiceErr_Unknown if no DNS-SD server was found: other mDNS error codes are in the range FFFE FF00 (-65792) to FFFE FFFF (-65537), and are listed in the dnssd.h file. An older version of this (the one used by avahi) is found here. A few additional error codes are defined in a later version from Apple.

If UxPlay stalls without an error message and without the server name showing on the client, this is either pre-UxPlay-1.60 behavior when no DNS-SD server was found, or a network problem.

• Avahi works at first, but new clients do not see UxPlay, or clients that initially saw it stop doing so after they disconnect.

This is usually because Avahi is only using the "loopback" network interface, and is not receiving mDNS queries from new clients that were not listening when UxPlay started.

To check this, after starting uxplay, use the utility avahi-browse -a -t in a different terminal window on the server to verify that the UxPlay AirTunes and AirPlay services are correctly registered (only the AirTunes service is used in the "Legacy" AirPlay Mirror mode used by UxPlay, but the AirPlay service is used for the initial contact).

The results returned by avahi-browse should show entries for uxplay like

+   eno1 IPv6 UxPlay                                        AirPlay Remote Video local
+   eno1 IPv4 UxPlay                                        AirPlay Remote Video local
+     lo IPv4 UxPlay                                        AirPlay Remote Video local
+   eno1 IPv6 863EA27598FE@UxPlay                           AirTunes Remote Audio local
+   eno1 IPv4 863EA27598FE@UxPlay                           AirTunes Remote Audio local
+     lo IPv4 863EA27598FE@UxPlay                           AirTunes Remote Audio local

If only the loopback ("lo") entries are shown, a firewall on the UxPlay host is probably blocking full DNS-SD service, and you need to open the default UDP port 5353 for mDNS requests, as loopback-based DNS-SD service is unreliable.

If the UxPlay services are listed by avahi-browse as above, but are not seen by the client, the problem is likely to be a problem with the local network.

2. uxplay starts, but stalls after "Initialized server socket(s)" appears, with the server name showing on the client (but the client fails to connect when the UxPlay server is selected).

This shows that a DNS-SD service is working, but a firewall on the server is probably blocking the connection request from the client. (One user who insisted that the firewall had been turned off turned out to have had two active firewalls (firewalld and ufw) both running on the server!) If possible, either turn off the firewall to see if that is the problem, or get three consecutive network ports, starting at port n, all three in the range 1024-65535, opened for both tcp and udp, and use "uxplay -p n" (or open UDP 7011,6001,6000 TCP 7100,7000,7001 and use "uxplay -p").

3. Problems after the client-server connection has been made:

If you do not see the message raop_rtp_mirror starting mirroring, something went wrong before the client-server negotiations were finished. For such problems, use "uxplay -d " (debug log option) to see what is happening: it will show how far the connection process gets before the failure occurs. You can compare your debug output to that from a successful start of UxPlay in the UxPlay Wiki.

If UxPlay reports that mirroring started, but you get no video or audio, the problem is probably from a GStreamer plugin that doesn't work on your system (by default, GStreamer uses the "autovideosink" and "autoaudiosink" algorithms to guess what are the "best" plugins to use on your system). A different reason for no audio occurred when a user with a firewall only opened two udp network ports: three are required (the third one receives the audio data).

Raspberry Pi devices work best with hardware GPU h264 video decoding if the Video4Linux2 plugin in GStreamer v1.20.x or earlier has been patched (see the UxPlay Wiki for patches). This is fixed in GStreamer-1.22, and by backport patches from this in distributions such as Raspberry Pi OS (Bullseye): use option -bt709 with the GStreamer-1.18.4 from Raspberry Pi OS. This also needs the bcm2835-codec kernel module that is not in the standard Linux kernel (it is available in Raspberry Pi OS, Ubuntu and Manjaro).

• If this kernel module is not available in your Raspberry Pi operating system, or if GStreamer < 1.22 is not patched, use option -avdec for software h264-decoding.

Sometimes "autovideosink" may select the OpenGL renderer "glimagesink" which may not work correctly on your system. Try the options "-vs ximagesink" or "-vs xvimagesink" to see if using one of these fixes the problem.

Other reported problems are connected to the GStreamer VAAPI plugin (for hardware-accelerated Intel graphics, but not NVIDIA graphics). Use the option "-avdec" to force software h264 video decoding: this should prevent autovideosink from selecting the vaapisink videosink. Alternatively, find out if the gstreamer1.0-vaapi plugin is installed, and if so, uninstall it. (If this does not fix the problem, you can reinstall it.)

There are some reports of other GStreamer problems with hardware-accelerated Intel HD graphics. One user (on Debian) solved this with "sudo apt install intel-media-va-driver-non-free". This is a driver for 8'th (or later) generation "*-lake" Intel chips, that seems to be related to VAAPI accelerated graphics.

If you do have Intel HD graphics, and have installed the vaapi plugin, but -vs vaapisink does not work, check that vaapi is not "blacklisted" in your GStreamer installation: run gst-inspect-1.0 vaapi, if this reports 0 features, you need to export GST_VAAPI_ALL_DRIVERS=1 before running uxplay, or set this in the default environment.

You can try to fix audio problems by using the "-as audiosink" option to choose the GStreamer audiosink , rather than have autoaudiosink pick one for you. The command "gst-inspect-1.0 | grep Sink | grep Audio" " will show you which audiosinks are available on your system. (Replace "Audio" by "Video" to see videosinks). Some possible audiosinks are pulsesink, alsasink, osssink, oss4sink, and osxaudiosink (macOS).

The "OpenGL renderer" window created on Linux by "-vs glimagesink" sometimes does not close properly when its "close" button is clicked. (this is a GStreamer issue). You may need to terminate uxplay with Ctrl-C to close a "zombie" OpenGl window. If similar problems happen when the client sends the "Stop Mirroring" signal, try the no-close option "-nc" that leaves the video window open.

4. GStreamer issues (missing plugins, etc.):

• clearing the user's GStreamer cache with rm -rf ~/.cache/gstreamer-1.0/* may be the solution to problems where gst-inspect-1.0 does not show a plugin that you believe is installed. The cache will be regenerated next time GStreamer is started. This is the solution to puzzling problems that turn out to come from corruption of the cache, and should be tried first.

If UxPlay fails to start, with a message that a required GStreamer plugin (such as "libav") was not found, first check with the GStreamer tool gst-inspect-1.0 to see what GStreamer knows is available. (You may need to install some additional GStreamer "tools" package to get gst-inspect-1.0). For, e.g. a libav problem, check with "gst-inspect-1.0 libav". If it is not shown as available to GStreamer, but your package manager shows the relevant package as installed (as one user found), try entirely removing and reinstalling the package. That user found that a solution to a "Required gstreamer plugin 'libav' not found" message that kept recurring was to clear the user's gstreamer cache.

If it fails to start with an error like 'no element "avdec_aac"' this is because even though gstreamer-libav is installed. it is incomplete because some plugins are missing: "gst-inspect-1.0 | grep avdec_aac" will show if avdec_aac is available. Some distributions (RedHat, SUSE, etc) provide incomplete versions of libav because of patent issues with codecs used by certain plugins. In those cases there will be some "extra package" provider like RPM fusion (RedHat) or packman (SUSE) where you can get complete packages (your distribution will usually provide instructions for this). The packages needed may be "libav*" or "ffmpeg*" packages: the GStreamer libav plugin package does not contain any codecs itself, it just provides a way for GStreamer to use ffmpeg/libav codec libraries which must be installed separately. For similar reasons, distributions may ship incomplete packages of GStreamer "plugins-bad", which is where "license-problematical" plugins go.

To troubleshoot GStreamer execute "export GST_DEBUG=2" to set the GStreamer debug-level environment-variable in the terminal where you will run uxplay, so that you see warning and error messages; see GStreamer debugging tools for how to see much more of what is happening inside GStreamer. Run "gst-inspect-1.0" to see which GStreamer plugins are installed on your system.

Some extra GStreamer packages for special plugins may need to be installed (or reinstalled: a user using a Wayland display system as an alternative to X11 reported that after reinstalling Lubuntu 18.4, UxPlay would not work until gstreamer1.0-x was installed, presumably for Wayland's X11-compatibility mode). Different distributions may break up GStreamer 1.x into packages in different ways; the packages listed above in the build instructions should bring in other required GStreamer packages as dependencies, but will not install all possible plugins.

The GStreamer video pipeline, which is shown in the initial output from uxplay -d, has the default form

appsrc name=video_source ! queue ! h264parse ! decodebin ! videoconvert ! autovideosink name=video_sink sync=false

The pipeline is fully configurable: default elements "h264parse", "decodebin", "videoconvert", and "autovideosink" can respectively be replaced by using uxplay options -vp, -vd, -vc, and -vs, if there is any need to modify it (entries can be given in quotes "..." to include options).

5. Mirror screen freezes:

This can happen if the TCP video stream from the client stops arriving at the server, probably because of network problems (the UDP audio stream may continue to arrive). At 3-second intervals, UxPlay checks that the client is still connected by sending it a request for a NTP time signal. If a reply is not received from the client within a 0.3 sec time-window, an "ntp timeout" is registered. If a certain number (currently 5) of consecutive ntp timeouts occur, UxPlay assumes that the client is "dead", and resets the connection, becoming available for connection to a new client, or reconnection to the previous one. Sometimes the connection may recover before the timeout limit is reached, and if the default limit is not right for your network, it can be modified using the option "-reset n", where n is the desired timeout-limit value (n = 0 means "no limit"). If the connection starts to recover after ntp timeouts, a corrupt video packet from before the timeout may trigger a "connection reset by peer" error, which also causes UxPlay to reset the connection.

• When the connection is reset, the "frozen" mirror screen of the previous connection is left in place, but does not block new connections, and will be taken over by a new client connection when it is made.

6. Protocol issues, such as failure to decrypt ALL video and audio streams from old or non-Apple clients:

• NEW As UxPlay only connects to one client at any time, it can work without the client pairing setup, allowing faster connections.

This is allowed by disabling "Supports Legacy Pairing" (bit 27) in the "features" code UxPlay advertises on DNS-SD Service Discovery. Most clients will then not attempt to setup the "shared secret key" for pairing.

• This new behavior (since UxPlay-1.65) can be reverted to the previous behavior by uncommenting the previous "FEATURES_1" setting (and commenting out the new one) in lib/dnssdint.h, and then rebuilding UxPlay.

A protocol failure may trigger an unending stream of error messages, and means that the audio decryption key (also used in video decryption) was not correctly extracted from data sent by the client. This should not happen for iOS 9.3 or later clients. However, if a client uses the same older version of the protocol that is used by the Windows-based AirPlay client emulator AirMyPC, the protocol can be switched to the older version by the setting OLD_PROTOCOL_CLIENT_USER_AGENT_LIST in UxPlay/lib/global.h. UxPlay reports the client's "User Agent" string when it connects. If some other client also fails to decrypt all audio and video, try adding its "User Agent" string in place of "xxx" in the entry "AirMyPC/2.0;xxx" in global.h and rebuild uxplay.

Note that Uxplay declares itself to be an AppleTV3,2 with a sourceVersion 220.68; this can also be changed in global.h. It had been thought that it was necessary for UxPlay to claim to be an older 32 bit AppleTV model that cannot run modern 64bit tvOS, in order for the client to use a "legacy" protocol for pairing with the server. However, UxPlay still works if it declares itself as an AppleTV6,2 with sourceVersion 380.20.1 (an AppleTV 4K 1st gen, introduced 2017, running tvOS 12.2.1). It was previously thought that use of "legacy" protocol requires bit 27 ("SupportsLegacyPairing") of the "features" plist code (reported to the client by the AirPlay server) to be set, but it was recently discovered that it was possible to switch that off (after a small protocol modification) to eliminate a 5 second delay by the client in making connections to the server.

The "features" code and other settings are set in UxPlay/lib/dnssdint.h.

Changelog

1.65 2023-05-31 Eliminate pair_setup part of connection protocol to allow faster connections with clients (thanks to @shuax #176 for this discovery); to revert, uncomment a line in lib/dnssdint.h. Disconnect from audio device when connection closes, to not block its use by other apps if uxplay is running but not connected. Fix for AirMyPC client (broken since 1.60), so its older non-NTP timestamp protocol works with -vsync.

1.64 2023-04-23 Timestamp-based synchronization of audio and video is now the default in Mirror mode. (Use "-vsync no" to restore previous behavior.) A configuration file can now be used for startup options. Also some internal cleanups and a minor bugfix that fixes #192.

1.63 2023-02-12 Reworked audio-video synchronization, with new options -vsync (for Mirror mode) and -async (for Audio-Only mode, to sync with client video). Option -vsync makes software h264 decoding of streamed videos with option -avdec viable on some recent Raspberry Pi models. Internal change: all times are now processed in nanoseconds units. Removed -ao option introduced in 1.62.

1.62 2023-01-18 Added Audio-only mode time offset -ao x to allow user synchronization of ALAC audio playing on the server with video, song lyrics, etc. playing on the client. x = 5.0 appears to be optimal in many cases. Quality fixes: cleanup in volume changes, timestamps, some bugfixes.

1.61 2022-12-30 Removed -t option (workaround for an Avahi issue, correctly solved by opening network port UDP 5353 in firewall). Remove -g debug flag from CMAKE_CFLAGS. Postpend (instead of prepend) build environment CFLAGS to CMAKE_CFLAGS. Refactor parts of uxplay.cpp

1.60 2022-12-15 Added exit with error message if DNSServiceRegister fails (instead of just stalling). Test for Client's attempt to using unsupported AirPlay 2 "REMOTE CONTROL" protocol (with no timing channel), and exit if this occurs. Reworked metadata processing to correctly parse DMAP header (previous version worked with DMAP messages currently received, but was not correct).

1.59 2022-12-12 remove "ZOOMFIX" compile option and make compilation with X11-dependence the default if X11 development libraries are detected (this now also provides fullscreen mode with a F11 or Alt+Enter key toggle); ZOOMFIX is now automatically applied for GStreamer < 1.20. New cmake option -DNO_X11_DEPS compiles uxplay without X11 dependence. Reworked internal metadata handling. Fix segfault with "-vs 0".

1.58 2022-10-29 Add option "-nohold" that will drop existing connections when a new client connects. Update llhttp to v8.1.0.

1.57 2022-10-09 Minor fixes: (fix coredump on AUR on "stop mirroring", occurs when compiled with AUR CFLAGS -DFORTIFY_SOURCE); graceful exit when required plugins are missing; improved support for builds on Windows. Include audioresample in GStreamer audio pipeline.

1.56 2022-09-01 Added support for building and running UxPlay-1.56 on Windows (no changes to Unix (Linux, *BSD, macOS) codebase.)

1.56 2022-07-30 Remove -bt709 from -rpi, -rpiwl, -rpifb as GStreamer is now fixed.

1.55 2022-07-04 Remove the bt709 fix from -v4l2 and create a new -bt709 option (previous "-v4l2" is now "-v4l2 -bt709"). This allows the currently-required -bt709 option to be used on its own on RPi without -v4l2 (sometimes this give better results).

1.54 2022-06-25 Add support for "Cover Art" display in Audio-only (ALAC) mode. Reverted a change that caused VAAPI to crash with AMD POLARIS graphics cards. Minor internal changes to plist code and uxplay option parsing.

1.53 2022-06-13 Internal changes to audio sync code, revised documentation, Minor bugfix (fix assertion crash when resent audio packets are empty).

1.52 2022-05-05 Cleaned up initial audio sync code, and reformatted streaming debug output (readable aligned timestamps with decimal points in seconds). Eliminate memory leaks (found by valgrind). Support for display of ALAC (audio-only) metadata (soundtrack artist names, titles etc.) in the uxplay terminal.

1.51 2022-04-24 Reworked options forVideo4Linux2 support (new option -v4l2) and short options -rpi, -rpifb, -rpiwl as synonyms for -v4l2, -v4l2 -vs kmssink, and -v4l2 -vs waylandsink. Reverted a change from 1.48 that broke reconnection after "Stop Mirroring" is sent by client.

1.50 2022-04-22 Added -fs fullscreen option (for Wayland or VAAPI plugins only), Changed -rpi to be for framebuffer ("lite") RPi systems and added -rpigl (OpenGL) and -rpiwl (Wayland) options for RPi Desktop systems. Also modified timestamps from "DTS" to "PTS" for latency improvement, plus internal cleanups.

1.49 2022-03-28 Addded options for dumping video and/or audio to file, for debugging, etc. h264 PPS/SPS NALU's are shown with -d. Fixed video-not-working for M1 Mac clients.

1.48 2022-03-11 Made the GStreamer video pipeline fully configurable, for use with hardware h264 decoding. Support for Raspberry Pi.

1.47 2022-02-05 Added -FPSdata option to display (in the terminal) regular reports sent by the client about video streaming performance. Internal cleanups of processing of video packets received from the client. Added -reset n option to reset the connection after n ntp timeouts (also reset after "connection reset by peer" error in video stream).

1.46 2022-01-20 Restore pre-1.44 behavior (1.44 may have broken hardware acceleration): once again use decodebin in the video pipeline; introduce new option "-avdec" to force software h264 decoding by libav h264, if needed (to prevent selection of vaapisink by autovideosink). Update llhttp to v6.0.6. UxPlay now reports itself as AppleTV3,2. Restrict connections to one client at a time (second client must now wait for first client to disconnect).

1.45 2022-01-10 New behavior: close video window when client requests "stop mirroring". (A new "no close" option "-nc" is added for users who wish to retain previous behavior that does not close the video window).

1.44 2021-12-13 Omit hash of aeskey with ecdh_secret for an AirMyPC client; make an internal rearrangement of where this hash is done. Fully report all initial communications between client and server in -d debug mode. Replace decodebin in GStreamer video pipeline by h264-specific elements.

1.43 2021-12-07 Various internal changes, such as tests for successful decryption, uniform treatment of informational/debug messages, etc., updated README.

1.42 2021-11-20 Fix MAC detection to work with modern Linux interface naming practices, MacOS and *BSD.

1.41 2021-11-11 Further cleanups of multiple audio format support (internal changes, separated RAOP and GStreamer audio/video startup)

1.40 2021-11-09 Cleanup segfault in ALAC support, manpage location fix, show request Plists in debug mode.

1.39 2021-11-06 Added support for Apple Lossless (ALAC) audio streams.

1.38 2021-10-8 Add -as audiosink option to allow user to choose the GStreamer audiosink.

1.37 2021-09-29 Append "@hostname" to AirPlay Server name, where "hostname" is the name of the server running uxplay (reworked change in 1.36).

1.36 2021-09-29 Implemented suggestion (by @mrbesen and @PetrusZ) to use hostname of machine runing uxplay as the default server name

1.35.1 2021-09-28 Added the -vs 0 option for streaming audio, but not displaying video.

1.35 2021-09-10 now uses a GLib MainLoop, and builds on macOS (tested on Intel Mac, 10.15 ). New option -t timeout for relaunching server if no connections were active in previous timeout seconds (to renew Bonjour registration).

1.341 2021-09-04 fixed: render logger was not being destroyed by stop_server()

1.34 2021-08-27 Fixed "ZOOMFIX": the X11 window name fix was only being made the first time the GStreamer window was created by uxplay, and not if the server was relaunched after the GStreamer window was closed, with uxplay still running. Corrected in v. 1.34

Building OpenSSL >= 1.1.1 from source.

If you need to do this, note that you may be able to use a newer version (OpenSSL-3.0.1 is known to work). You will need the standard development toolset (autoconf, automake, libtool). Download the source code from https://www.openssl.org/source/. Install the downloaded openssl by opening a terminal in your Downloads directory, and unpacking the source distribution: ("tar -xvzf openssl-3.0.1.tar.gz ; cd openssl-3.0.1"). Then build/install with "./config ; make ; sudo make install_dev". This will typically install the needed library libcrypto.*, either in /usr/local/lib or /usr/local/lib64.

(Ignore the following for builds on MacOS:) On some systems like Debian or Ubuntu, you may also need to add a missing entry /usr/local/lib64 in /etc/ld.so.conf (or place a file containing "/usr/local/lib64/libcrypto.so" in /etc/ld.so.conf.d) and then run "sudo ldconfig".

Building libplist >= 2.0.0 from source.

(Note: on Debian 9 "Stretch" or Ubuntu 16.04 LTS editions, you can avoid this step by installing libplist-dev and libplist3 from Debian 10 or Ubuntu 18.04.) As well as the usual build tools (autoconf, automake, libtool), you may need to also install some libpython*-dev package. Download the latest source with git from https://github.com/libimobiledevice/libplist, or get the source from the Releases section (use the *.tar.bz2 release, not the *.zip or *.tar.gz versions): download libplist-2.3.0, then unpack it ("tar -xvjf libplist-2.3.0.tar.bz2 ; cd libplist-2.3.0"), and build/install it: ("./configure ; make ; sudo make install"). This will probably install libplist-2.0.* in /usr/local/lib. The new libplist-2.3.0 release should be compatible with UxPlay; libplist-2.2.0 is also available if there are any issues.

(Ignore the following for builds on MacOS:) On some systems like Debian or Ubuntu, you may also need to add a missing entry /usr/local/lib in /etc/ld.so.conf (or place a file containing "/usr/local/lib/libplist-2.0.so" in /etc/ld.so.conf.d) and then run "sudo ldconfig".

Disclaimer

All the resources in this repository are written using only freely available information from the internet. The code and related resources are meant for educational purposes only. It is the responsibility of the user to make sure all local laws are adhered to.

This project makes use of a third-party GPL library for handling FairPlay. The legal status of that library is unclear. Should you be a representative of Apple and have any objections against the legality of the library and its use in this project, please contact the developers and the appropriate steps will be taken.

Given the large number of third-party AirPlay receivers (mostly closed-source) available for purchase, it is our understanding that an open source implementation of the same functionality wouldn't violate any of Apple's rights either.

UxPlay authors

[adapted from fdraschbacher's notes on RPiPlay antecedents]

The code in this repository accumulated from various sources over time. Here is an attempt at listing the various authors and the components they created:

UxPlay was initially created by antimof from RPiPlay, by replacing its Raspberry-Pi-adapted OpenMAX video and audio rendering system with GStreamer rendering for desktop Linux systems; the antimof work on code in renderers/ was later backported to RPiPlay, and the antimof project became dormant, but was later revived at the current GitHub site to serve a wider community of users.

The previous authors of code included in UxPlay by inheritance from RPiPlay include:

• EstebanKubata: Created a FairPlay library called PlayFair. Located in the lib/playfair folder. License: GNU GPL
• Juho Vähä-Herttua and contributors: Created an AirPlay audio server called ShairPlay, including support for Fairplay based on PlayFair. Most of the code in lib/ originally stems from this project. License: GNU LGPLv2.1+
• dsafa22: Created an AirPlay 2 mirroring server AirplayServer (seems gone now), for Android based on ShairPlay. Code is preserved here, and see here for the description of the analysis of the AirPlay 2 mirror protocol that made RPiPlay possible, by the AirplayServer author. All code in lib/ concerning mirroring is dsafa22's work. License: GNU LGPLv2.1+
• Florian Draschbacher (FD-) and contributors: adapted dsafa22's Android project for the Raspberry Pi, with extensive cleanups, debugging and improvements. The project RPiPlay is basically a port of dsafa22's code to the Raspberry Pi, utilizing OpenMAX and OpenSSL for better performance on the Pi. License GPL v3. FD- has written an interesting note on the history of Airplay protocol versions, available at the RPiPlay github repository.

Independent of UxPlay, but used by it and bundled with it:

• Fedor Indutny (of Node.js, and formerly Joyent, Inc) and contributors: Created an http parsing library called llhttp. Located at lib/llhttp/. License: MIT