Toaster: Live Music Visualizer

Toaster turns your TV into a music display for the room. It listens and writes what it hears out as live code: named lines typed onto the screen, big enough to read from the sofa, lighting up as they play over moving visuals. It finds the beat, the kick, clap and hats, the bass line, the chords and the key, and keeps rewriting the code as the song goes on. It's a live reconstruction for show, not an exact transcription.

The code is Strudel, the open-source live-coding environment for music.

It runs with nothing pressed. The first time, it opens on the demo beat; after that, on whatever you picked last, with an ID card showing the tempo and key, and a new background every 32 bars.

What it listens to
• Your iPhone as the mic: Toaster hears the room, so the music on your speakers, a DJ or a band becomes code (Apple TV 4K, 2nd generation or later, with an iPhone on iOS 17 or later)
• Your own internet radio: add a station by typing its stream address, with a name if you like, and it's kept on your Apple TV. When a stream sends the song's title, Toaster shows it and looks for the cover
• The demo beat, built in, to start right away

What you see
• 13 backgrounds, including a spectrum, a tunnel, a spiral, a pitch wheel, a spectrogram, rain and a scope
• Chrome: a pool of liquid chrome that the kick drops beads into
• Worlds: close-ups of everyday materials filmed as planets, cutting to the next one on the kick, in looks such as film, ink, risograph, cyanotype, thermal, night vision, CRT and VHS
• Scenery: eleven animated scenes, from a lake and a campfire to a city in the rain and a koi pond
• A mosaic that cuts a radio song's cover, or one of a dozen bundled artworks, into squares and scrambles them in time with the music
• A dot orb, punchcard or domino blocks, a liquid glass lens over the code, and five color themes
• Drop effects, off until you turn them on: when the kick comes back after a break, a retro desktop floods with pop-up windows, a crash screen flashes up, or a frozen window smears across the visuals

Your iPhone as the camera
With Continuity Camera, your iPhone puts you behind the code: tinted to the theme, with your eyes and mouth blown up, or drawn as text, with seven effects including cut-out, glass, dots and voxels. Your hands work as a remote: frame a window with your fingers to see through one of 16 filters, make a circle with your hands to open a portal, and hold up two fingers for the next theme or a fist to hush the code.

The Siri Remote
Click up or down to change the background, left or right to move between your stations. Swipe to change the background's look or the theme. Play/Pause turns the background changes off and on, and a click in the middle opens the picker with everything else: what to listen to, the picture, the size of the code and the camera.

Top Shelf
With Toaster in the top row of the Home Screen, its scenes play across the Top Shelf. Pick one and Toaster opens on it.

Everything Toaster hears and sees stays on your Apple TV. No account, no ads, no tracking.

Toaster is a native port of Toaster, the open-source app by Colin (github.com/StopBanning/toaster), used under its MIT licence. It is an independent app, not made by or affiliated with the Strudel project.