MScopes

Real-time music visualizer for macOS. It listens to whatever the Mac is playing — Apple Music, Spotify, a browser, a DAW — through a system audio tap, so it reacts to the digital signal itself: at any volume, on headphones, on speakers. It plays the classic AVS preset language of the Winamp era faithfully and adds a modern GPU effect layer on the same engine. An Apple Music visualizer plugin ships inside the app.

Download: MScopes.dmg — the latest release, signed and notarized (macOS 14.4 or later, Apple silicon and Intel); all versions on the Releases page. Home: mscopes.com. Source: this repository, BSD 3-Clause.

What it does

• System audio in. No cables, no loopback drivers: a CoreAudio process tap captures the mix the Mac is playing. First launch asks once for permission.
• Classic AVS presets, faithfully. The complete component set — nested Effect Lists with every blend mode, Superscope, Dynamic Movement / Shift / Distance Modifier, Color Modifier, Texer II, Triangle, Global Variables, Buffer Save, Set Render Mode, Custom BPM, the common APEs — running on our own EEL virtual machine. Line modes, 8-bit truncation and list persistence are reproduced, so decades-old presets look the way they did. Over a community archive of 13,440 presets, all but 10 (Windows-only components: Text, Picture, video, external DLLs) load and render.
• Modern effects on the same stack. Bloom, kaleidoscope, chromatic aberration, shockwave, glitch, anamorphic streaks, lens, radial blur, edge glow, duotone, heat shimmer, CRT, tone mapping, vignette — and pixel_shader: EEL scripts transpiled to Metal and run per pixel.
• A GPU engine. Zero-copy Metal backend over the framebuffer's own memory, deferred command buffers, the hot classic effects ported to compute kernels with the CPU loops as fallback. A steady 60 fps, paced by the display.
• Beat detection. Energy-flux onsets, BPM estimate and beat phase from the live signal, exposed to scripts the way AVS presets expect.
• Apple Music plugin. A visualizer inside Music, installed with one click from the app. Today it runs the bar/waveform renderer with the shared beat detector; the preset engine is linked in but not yet routed to it.
• Preset browser, albums, script editor, macro knobs. Point the app at your .avs library: every preset is listed and searchable, numbered sequences become albums that play in order.
• A headless renderer. vizrender turns a preset and a WAV into PNG frames, and builds with CMake on any platform — it is how the engine is tested, and how the pictures below were made.

Gallery

Built-in presets, rendered by the engine:

Presets from the Winamp era, unmodified .avs files played by MScopes (the work of their authors — Justin Frankel, lone, and others — and not part of this repository):

The app: its own header over the visuals, the sidebar alongside. Widget mode (View ▸ Widget Mode) keeps just the visuals in a small always-on-top window, and the Dock icon shows a live spectrum while music plays.

Presets

MScopes ships with its own presets. The thousands of community .avs presets from the Winamp era are content you bring: pick a library folder in the app and every .avs underneath is listed. Where to find packs, how albums work, and why some presets are black on their own: docs/PRESETS.md.

Building

The engine, the headless renderer and the self-tests need a C++17 compiler and CMake, on any platform:

tools/run-tests.sh                       # configure, build, run every test
build/cmake/vizrender presets/tests/05-set-render-mode.avs --audio song.wav --out frames
build/cmake/vizrender --list             # built-in presets; --builtin "<name>" renders one

The macOS app and the Music plugin are one XcodeGen project:

brew install xcodegen cmake
cd apple && xcodegen generate
xcodebuild -project MScopes.xcodeproj -scheme App -configuration Debug \
           -destination 'generic/platform=macOS' build

Building App also builds the plugin and embeds it; the app's Install… button copies it into ~/Library/iTunes/iTunes Plug-ins/ for Music. Notes on targets and dev aids: apple/README.md. Signing, notarization and the release DMG: docs/SIGNING.md.

Layout

core/                   the portable engine (plain C++; CMake builds it anywhere)
  effects/ script/      effect library + EEL VM and the EEL→MSL transpiler
  preset/               .avs (classic) and JSON preset loaders
  audio/                Analyzer (FFT → VizFrame) + BeatDetector
  gpu/                  GpuFx.h backend interface; metal/ implementation; a stub elsewhere
  platform/             the porting seams: fft, page memory, PNG output
  tests/ tools/         self-tests; vizrender
apple/                  one XcodeGen project: VizCore lib, the macOS App, the Music plugin
presets/tests/          the repo's own .avs fixtures (tools/make-test-presets.py)
tools/                  run-tests.sh, release.sh, preset archive helpers
docs/                   PRESETS.md, SIGNING.md, media/
CMakeLists.txt          engine + tools + tests, every platform

The engine has no Apple dependency outside core/platform/ and core/gpu/metal/; a Windows or Linux front-end would sit beside apple/.

Credits and license

BSD 3-Clause (LICENSE). MScopes is a fresh project, not a fork of the Winamp source tree. Its classic effects are re-implementations of the algorithms in the open-sourced vis_avs, credited in NOTICE.md together with Apple's iTunes Visual SDK. "Winamp", "Nullsoft" and "AVS" are the marks of their owners; MScopes is not affiliated with or endorsed by them.