Audio Waveforms

Railcut displays real amplitude waveforms on audio clips. This makes it easier to find beats, cuts, pauses, and sync points without having to play the audio.

Enabling waveforms

Go to → Settings → Cache and turn on Show Waveforms. Waveforms are off by default to avoid unnecessary processing on comps where you don’t need them.

How waveform generation works

When you open a comp with audio layers and waveforms are enabled, Railcut:

1. Reads the source file path from each audio layer
2. Checks the disk cache for existing waveform data
3. If not cached, uses a bundled ffmpeg process to extract the audio and compute amplitude samples
4. Writes the result to the cache
5. Renders the waveform on the clip

A “Generating Audio Waveforms” toast notification appears while extraction is running. Extraction is fast for most files — a few seconds per clip.

Tip

Waveform data is cached by source file. Once generated, waveforms load instantly on subsequent opens — even across AE sessions.

Supported formats

Audio-only files:

• .wav, .mp3, .aac, .aiff / .aif, .flac, .ogg, .m4a

Video containers (audio track extracted):

• .mp4, .mov, .mxf, .mkv, and most other common video containers with an embedded audio track

What doesn’t get waveforms

These layer types don’t generate waveforms:

• Precomps — audio is rendered internally by AE, not a source file
• Solids, text, shape, adjustment, null, camera, light — no audio source

If your footage layer has audio but Railcut isn’t showing a waveform, check that the footage isn’t missing or offline in AE.

Note

If your footage files are stored on a path containing non-ASCII characters (e.g., accented letters, Japanese or Chinese characters), waveform extraction may fail silently. This is a known limitation of the audio extraction engine.

Cache management

Open → Settings → Cache to manage the waveform cache.

Controls:

• Show Waveforms toggle
• Max waveform cache size — limits total disk space used by the waveform cache. Options: 256 MB, 512 MB, 1 GB, 2 GB (default), 5 GB, Unlimited. When the limit is reached, older entries are pruned automatically.
• Regenerate for This Comp — re-extracts waveform data for all audio layers in the current comp
• Clear All Waveform Cache — removes all cached waveform data

Clearing the cache only removes Railcut’s waveform data files — it has no effect on your AE project or source footage.

Waveform display

Waveforms scale with the clip as you zoom in or out on the timeline. Zoom in to see individual beats more clearly.

Waveform generation runs as a background process and doesn’t block editing. The toast notification disappears when all waveforms for the current comp are ready.