Handwave.

A browser instrument, played by hand.

Handwave is a standalone browser instrument for controlling a vocoder with hand gestures, designed to be usable without music-production expertise.

Play Handwave View source Explore how it works ↓

0 installs
runs on your webcam

Handwave browser vocoder performance console — Handwave: a browser vocoder controlled by hand tracking, with presets and live performance controls.

01 / THE BUILD

The starting point

Gesture-controlled vocoder demos are compelling but often depend on specialist tools, DAWs, or unclear setup. The goal was to make a local, private, beginner-friendly instrument that works from the browser first.

02 / THE BUILD

The experience

01
Demo mode produces synthetic hand values and tone so the instrument is usable before permissions.
02
Simple Performance Mode exposes presets and plain-language controls for voice clarity, brightness, smoothness, and note snap.
03
Calibration wizard captures primary hand, pinch range, and comfortable reach.
04
Advanced panel keeps MIDI CC mapping available without crowding the main performance view.

03 / THE BUILD

Under the hood

Vite + React frontend with pure domain modules for hand math, calibration, smoothing, pitch snapping, and presets. MediaPipe handles hand tracking, Web Audio AudioWorklet runs the vocoder DSP, and optional Web MIDI sends CC values to external tools.

INTERACTIVE / SYSTEM WALKTHROUGH

From a gesture to a sound.

Follow the signal through Handwave. Select a step to see what happens and inspect its source.

Microphone → Audio engine is a separate sound input.

STEP 1 / 5

Camera

The performance starts with a front-facing camera stream. Video frames supply movement; the camera adapter does not request audio.

IN: Your hand in the camera view
OUT: A video stream for the tracker

Camera access starts only when the player requests it. A denied request returns a readable error.

src/adapters/camera.ts ↗

Optional branch: MIDI

The control state can also produce rate-limited MIDI CC messages for a selected external output. This branch sends control values, not audio. It needs explicit MIDI access.

Inspect MIDI adapter ↗

Source reviewed · 47c98d8 · September 27, 2026

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