Audio Fade

Audio Fade

Apply fade-in at the start and fade-out at the end without changing clip length.

Rules

When this skill applies, read and follow skill-dependency-manager — run scripts as documented, install missing tools into .dependency/.

Quick Start

Default: 1 s fade-in and fade-out, output to <audio-dir>/audio-fade/<audio-name>:

.dependency/python/python .ai/audio-fade/fade.py --audio path/to/audio.wav

Fade-in only (keep full end level):

.dependency/python/python .ai/audio-fade/fade.py --audio path/to/audio.wav --no-fade-out

Custom durations (seconds):

.dependency/python/python .ai/audio-fade/fade.py --audio audio/sfx.wav -fi 0.05 -fo 0.15

Duration Guidelines

Fade-in + fade-out must stay shorter than file duration. Very short clips need smaller values.

Common Flags

--audio · -fi / --fade-in · -fo / --fade-out · --no-fade-in · --no-fade-out · -o / --output

.dependency/python/python .ai/audio-fade/fade.py --audio audio/sfx.wav -fi 0.03 -fo 0.08

Originals are never modified. Input must be a single audio file (--audio), not a directory. Supported: .wav, .mp3, .ogg, .flac, .aac, .m4a, .wma.

Fades use FFmpeg afade with the linear tri curve. The script probes clip duration and places fade-out at duration - fade_out.

Scope

• Fade shapes volume at clip boundaries without changing its duration.
• Trim removes silence or crops boundaries; use the audio-trim skill.
• Crossfade overlaps two clips and is not performed by this skill.

Agent Notes

1. Use the bundled script, not hand-written afade filters.
2. Looping BGM — avoid fade-out on loop assets; use --no-fade-out or fade-in only for one-shot intros.
3. Clicks with instant attack → --no-fade-in or lower -fi (e.g. 0.01).
4. Tail cut off abruptly after fade → increase -fo; tail too soft → decrease -fo.

CLI

Copy-paste commands: cli/audio-fade.md