LoupixDeck.Plugin.Audio

Audio integration plugin for LoupixDeck, built against LoupixDeck.PluginSdk.

Windows via WASAPI (NAudio), Linux via pactl (PulseAudio / pipewire-pulse). Sound playback on Linux uses paplay. Formats libsndfile cannot decode (mp3, m4a) are decoded by ffmpeg and piped into paplay, or played by mpv; plain ffplay is used only when no specific playback device is selected, because it offers no way to target one. Selecting a device therefore needs ffmpeg plus paplay, or mpv — with none of them present the sound is skipped rather than played on the wrong device.

Commands

Audio.OutputDevices / Audio.InputDevices — open a touch-screen folder listing the active audio endpoints; a sub-folder per device shows the live volume and a mute toggle (the first rotary adjusts volume).

Audio.CurrentOutput — a touch-screen button that shows the active output device's alias and opens the output-device picker when pressed. The label refreshes every two seconds, so it can lag a default-device change made outside the app (from the OS sound settings or pactl) by a few seconds, and reads "No device" when none is set.

It takes the same five tile parameters as Audio.OutputDevices (see below), which set the look of the picker it opens.

Audio.CycleOutput — make the next output device the system default, so one button switches between speakers and headset. The button shows the device in use; on a dial the new name flashes next to it. Without a device list it walks the devices the output picker shows (the ones not hidden in the settings). The devices parameter limits it to a list, in that order, separated by |, for example Speakers|Headset. An entry is a device's alias, its name or its id; when nothing matches exactly, a part of the alias or name does. Windows device names such as Speakers (Realtek(R) Audio) contain a closing parenthesis, which a binding cannot carry, so name that device by a part (Realtek) or give it an alias. A device in the list that is not connected is skipped.

Audio.VolumeUp / Audio.VolumeDown / Audio.MuteToggle — act on one device, assigned from the command menu (Audio → Output/Input Devices). The volume step is editable per assignment.

On a touch key Audio.MuteToggle shows its state live when the showState parameter is on: a speaker or microphone in white with the level below it, crossed out in red with "Muted" while muted. A newly assigned toggle has it on. The key is drawn on a transparent background, so the wallpaper shows through. A toggle assigned before the parameter existed keeps its static icon; assign it again to get the live look.

Audio.Mute / Audio.Unmute / Audio.SetMute — set a device's mute state instead of toggling it, so running the command twice does the same thing as running it once. That is what a macro or multi-action needs. Audio.SetMute takes the state (muted, on by default) as a parameter. The application counterparts are Audio.AppMute / Audio.AppUnmute / Audio.AppSetMute.

The first entry under Output Devices and Input Devices, "Default Output" and "Default Input", follows whatever device is the system default at the moment the command runs (the binding stores @default or @defaultInput instead of a device id). "Mic Mute" at the top of the menu is a mute toggle bound to the default input, so it keeps working when the microphone changes.

Audio.Mixer — open a per-application mixer on the touch screen. Tap a tile to select an application, the first rotary then adjusts it and its press mutes. It lists the applications playing on any output device, not just the default one, so a virtual mixer that routes each application to a device of its own does not hide them. The Windows audio engine is left out, and the system sounds session is listed as "System Sounds".

Each tile shows the application's icon, its level and its name. On Windows the icon and the name (the executable's file description, for example "Google Chrome") come from the executable. On Linux the name comes from the application's .desktop file and the icon from the hicolor icon theme or /usr/share/pixmaps, Flatpak exports included; only PNG icons are read, so an application that ships only an SVG icon shows a speaker, as does one without an icon. The command has two parameters, so every assignment can look different (five parameters):

• layout — Top (icon above level and name, the default), Left (icon on the left, name over two lines), Background (faded icon behind a large level) or Arc (faded icon inside an arc that shows the level).

• font — Smooth (the default) draws the text in LoupixDeck's anti-aliased font. Pixel draws it in a 5x7 bitmap font that sits exactly on the panel's pixels: uppercase, 12 characters per line on a 90 px key. A name the bitmap font cannot spell (for example Chinese or Cyrillic) is drawn in the smooth font automatically.

• transparent (on by default) — no tile background: the wallpaper (or the device's black) shows through, and the level's track becomes translucent. The selected tile is still marked by its frame.

• outlined (on by default) — a dark outline around the text, which keeps it legible on a transparent tile over a busy wallpaper. In the smooth font the outline is drawn by LoupixDeck and is a little heavier than the bitmap font's one pixel.

• scroll — which tiles run a name that is wider than the tile: All (the default), Selected (only the tile with the frame) or Off. A scrolling name moves left at a constant speed and comes back in from the right; a name that is not allowed to scroll is cut with an ellipsis. The layout Left never scrolls, it breaks the name over two lines. Scrolling redraws the folder about ten times a second for as long as a name is running.

An assignment saved before these parameters existed uses the defaults (transparent background, outlined text, everything scrolls); untick the two options for a solid tile without outline.

Audio.OutputDevices and Audio.InputDevices open the device list with the same tiles and take the same five parameters. A tile shows the device's icon (speaker, or microphone for inputs), its volume and its name; the default device is named in bold, white type (no selection frame), and a muted device is greyed out and struck through. Tapping a tile opens that device's volume, mute and default controls. The levels follow the devices while the folder is open. A list saved before the tiles existed picks up the new look with the defaults.

The tiles are drawn at the size of the key, so they stay sharp on a calibrated key (74 px, for example). That needs LoupixDeck with Plugin SDK 1.28.0 or newer; an older LoupixDeck receives a 90 px picture and scales it to the key, which softens the pixel font.

Audio.AppVolumeUp / Audio.AppVolumeDown / Audio.AppMuteToggle / Audio.AppSetVolume — act on one application, assigned from the command menu under Audio → Applications. A binding stores the process name, so it survives that application restarting. "Foreground App" follows the focused window on Windows, and on Linux for X11 and XWayland windows (resolved with xprop, which must be installed). A native Wayland window carries no _NET_WM_PID, so under a Wayland session the dial stays empty for applications that do not go through XWayland.

Audio.VolumeTile / Audio.AppVolumeTile — a touch key that shows one device's or one application's level and mute state live, drawn like a mixer tile (a muted target is greyed out and struck through); pressing it toggles mute. Assigned from the command menu: "Volume Tile" under a device, and "Mute Toggle" under an application when the menu is opened for a touch key. On a button or dial an application's "Mute Toggle" is still Audio.AppMuteToggle, which keeps its static icon. It takes the target plus the tile parameters layout, font, transparent and outlined described below; a name that does not fit is cut, as a single key does not scroll. An application that is not playing is shown greyed out at 0 %. The existing mute and volume buttons keep their look; the tile is a separate command to pick.

Audio.SetVolume / Audio.AppSetVolume — set a device or an application to a fixed level in percent, editable per assignment.

Audio.SetDefaultDevice — make one device the system default. On Linux the already-playing streams are moved across to it as well.

Audio.PlaySound — play an audio file. Set a sound folder in the plugin settings; its files then appear in the command menu under Audio → Play Sound, with sub-folders as sub-menus. Every press starts its own playback, so repeated presses overlap — unless stop on second press is enabled, where a press while the sound is still running stops it instead.

Audio.StopSounds — stop every sound this plugin is currently playing. Works regardless of the stop on second press setting and affects only the plugin's own playback, not the audio of other applications.

Settings

• Sound folder — folder scanned for .wav, .mp3, .flac, .m4a and .aiff files (.ogg on Linux only — Windows has no Vorbis decoder).
• Stop on second press — off by default. When on, pressing a sound button again stops that sound rather than layering a second playback on top. A sound that already ended on its own simply starts again. Buttons sharing the same file share the toggle.
• Playback device — one toggle per output device; enable exactly one to route Audio.PlaySound there. With none enabled the system default is used. A selected device that is currently unplugged keeps its selection and stays listed, so unplugging it does not silently reset the choice.
• Device aliases — short names replacing the OS device names.
• Side-strip volume bars — vertical bars or stacked horizontal segments.

Build & deploy

dotnet build LoupixDeck.Plugin.Audio.csproj -c Release

Copy the build output together with plugin.json into LoupixDeck/plugins/audio/.