waveform-editor

An Ableton Live extension that opens an audio clip in a sample-level waveform and pitch editor — a ProTools/Melodyne-style quality-of-life feature for spot-fixing pops, clicks, clipping, and tuning without leaving Live.

How it works

Live's extension API exposes no way to read or write a clip's raw samples in place, so the extension does a render → edit → new-clip round-trip:

1. Right-click an audio clip (or an arrangement time-selection on an audio track) → Edit clip / Edit selection.
2. The clip's pre-FX audio for that region is rendered to a temporary WAV and decoded. (Session clips, which aren't on the timeline, are read straight from their source file.)
3. A modal canvas editor opens with the audio. Edit it, audition with the built-in transport, then Apply.
4. Apply writes the result as a lossless 32-bit-float WAV, imports it, and drops it on a new audio track, time-aligned under the original.

The original clip is never modified — the edited copy lives on its own track so you can A/B and keep it or discard it.

The editor

Three tabs — Waveform, Pitch, and Spectral — share the same zoom/pan, undo/redo (up to 50 steps), and transport. Press Space to play/stop; the waveform tab plays from the selection (or the whole region), the pitch tab from a click-set play head.

Waveform tab

• Pencil — drag to freehand-redraw samples.
• Heal — drag across a span; it's smoothly bridged (Catmull-Rom), the fastest way to kill a click or de-clip a peak.
• Select — drag a range (auto-snaps to zero crossings; toggle with Z), then apply:
  • Fade In / Out with selectable curves.
  • Gain in dB.
  • Reverse.
  • Pitch bend in semitones.
• Per-channel lanes with optional Link (mirror edits across channels), zoom/pan (wheel, Ctrl/Cmd+wheel), and Ctrl/Cmd+A to select all.
• Spectro (toggle with G) — a per-channel spectrogram strip under each lane, locked to the same time axis (log-frequency, Nyquist at top). Clicks and pops show as bright vertical broadband streaks, so they're far easier to find than in the time-domain trace. Click/drag the strip to mark a range, then switch to Heal to repair it; drag the strip's top edge to resize it. It re-renders after each edit and follows zoom/pan.

Pitch tab

• Detects the monophonic pitch contour, segments it into notes, and lays them on a piano roll with a vertical keyboard.
• Drag a note up/down to retune — audio is transposed via TD-PSOLA (duration- and formant-preserving). Snaps to semitone; hold Alt for fine.
• Correct All snaps every note to the nearest semitone.
• Reset & Re-analyze reverts to the original audio and re-detects.

Spectral tab

A drawable, invertible log-frequency spectrogram per channel — paint directly on the spectrum to fix problems that are invisible in the waveform. Unlike the waveform tab's display-only Spectro strip, this keeps a full STFT and resynthesizes (weighted overlap-add) on each stroke, so edits round-trip back into the audio. The brush is time-pressed like a Photoshop brush: dwelling or overlapping passes deepen the effect, quick swipes barely touch it.

• Attenuate (A) — paint toward a noise floor to cut unwanted content (hum, bleed, broadband clicks).
• Restore (R) — paint the mask back toward the original (un-erase).
• Heal (H) — paint over a click/blemish to fill it from the surrounding frames.
• Draw (D) — synthesize fresh tones into empty spectrum.
• Brush size (S/M/L/XL) and Flow (Low → Instant) set how fast the brush bites; Heat/Rainbow toggle the color scheme.

Limitations

• The whole region is loaded into the editor, so length is bounded by memory and render time — very long clips will be slow. Use a time-selection for fine click repair.
• The edited clip is unwarped sounding audio; the original's warp markers and fades are not carried over.
• The render captures everything sounding on that track in the range, so the target clip should sit alone over the edited span.
• Pitch detection is monophonic — chordal or polyphonic material will mis-segment.

Get Started

Learn about building extensions: https://ableton.github.io/extensions-sdk/

Setup

The path to Ableton Live's Extension Host module is stored in .env as EXTENSION_HOST_PATH. The generator filled this in for you; edit it if your install moves.

Scripts

npm start                  # build + run in Live's Extension Host
npm run build              # production bundle of src/extension.ts
npm run build:dev          # dev bundle (sourcemaps, not minified)
npm run package            # build for production + create a .ablx archive