---
name: clip-trim
description: Auto-trim dead air from clips. Detects leading/trailing silence in audio (or audio track of a video) AND leading/trailing black frames in video, then trims both. Pure ffmpeg silencedetect + blackdetect — no ML deps, no re-encode for video when possible. Folder mode trims every file in a directory in parallel. Use when the user has clips with dead intros, fade-up black frames, silent leading air, render-padding at start/end, or just wants every file in a folder cleaned up.
---


# clip-trim

Trim leading/trailing silence + black frames from any audio or video.

## Single file

```bash
python3 ~/.claude/skills/clip-trim/scripts/trim.py --input clip.mp4
# → clip_trimmed.mp4 — black frames + silence stripped at both ends
```

## Folder of clips

```bash
python3 ~/.claude/skills/clip-trim/scripts/trim.py --input ~/exports --recursive
# trims every audio/video file in parallel, writes <name>_trimmed.<ext>
```

## Tune detection

```bash
python3 ~/.claude/skills/clip-trim/scripts/trim.py --input clip.mp4 \
  --silence-db -40 \
  --silence-min 0.3 \
  --black-threshold 0.1 \
  --black-min 0.4 \
  --pad 0.05
```

- `--silence-db` — silence threshold in dB (default `-50`, lower = more aggressive)
- `--silence-min` — min silence duration to count (default `0.5s`)
- `--black-threshold` — pixel threshold for black detection (default `0.1`, lower = stricter)
- `--black-min` — min black duration (default `0.5s`)
- `--pad` — keep N seconds of padding (default `0.05`)

## Audio-only / video-only mode

```bash
python3 ~/.claude/skills/clip-trim/scripts/trim.py --input clip.mp4 --no-black
# only trims silence

python3 ~/.claude/skills/clip-trim/scripts/trim.py --input clip.mp4 --no-silence
# only trims black frames
```

## In-place (overwrite)

```bash
python3 ~/.claude/skills/clip-trim/scripts/trim.py --input clip.mp4 --in-place
# replaces original
```

## What it actually does

1. ffmpeg `silencedetect` filter on the audio → start/end silence ranges
2. ffmpeg `blackdetect` filter on the video → start/end black ranges  
3. Pick the conservative (later) start and conservative (earlier) end across both
4. Re-cut with `-ss` / `-to` — uses `-c copy` when possible (fast, no quality loss)

## Flags

- `--input` — file or folder
- `--recursive` — descend into subfolders
- `--output` — output file (single-file mode)
- `--in-place` — overwrite original
- `--no-silence` — skip silence detection
- `--no-black` — skip black-frame detection (audio files always skip)
- `--threads` — parallel folder workers (default 4)
- `--silence-db` / `--silence-min` / `--black-threshold` / `--black-min` / `--pad`

## Pairs well with

- `vid-rip` → rip clip → `clip-trim` to remove the inevitable leading silence
- `sample-pack` → trim before packaging samples
- `loudness-fix` → trim, then master