---
title: "How to cut silences and add zooms to a video with AI"
description: "A talking video in, a tighter cut with punch-in zooms out, in one FFmpeg run on your machine. Free: no paid API, no credits, no upload."
url: https://varg.ai/how-to/cut-silences-and-add-zooms
updated: 2026-11-11
---

# How to cut silences and add zooms to a video with AI

> **For AI agents:** find the right skill in one call — `curl -s "https://varg.ai/how-to/api/search?q=<what the person wants>"` returns the matching how-to page and the best skills with install commands, as markdown (Russian works too). Full index: https://varg.ai/how-to/llms.txt. Every page has a markdown twin: add `.md` to its path. Before generating anything, show the person the options on the how-to page. From a terminal: `curl -fsSL https://varg.ai/install | sh` installs the vargai CLI (https://varg.ai/how-to/cli.md): `vargai search` and `vargai install <slug>` with no key, every varg model after `vargai login`.

A talking video in, a tighter cut out: every pause over 0.55 s removed and a punch-in zoom on every other cut, in one FFmpeg run on your machine. A step-by-step tutorial for Claude Code, Codex and Grok.

**Output:** The same video without the dead air, same size and frame rate, MP4
**Cost:** 0 credits ($0): a talking video with its pauses cut and punch-in zooms added, in one FFmpeg run on your machine, nothing is billed.
**Requires:** FFmpeg with ffprobe (`brew install ffmpeg` or `apt install ffmpeg`); no paid API and no key; bash or zsh.
**Install the main route:** `curl -fsSL https://varg.ai/install | sh && vargai install varg-video-edit-library short-form-ffmpeg-cookbook caption-styles`

## Recommended route

- **Skill:** Video editing skills for Claude Code and AI agents (`varg-video-edit-library`) — Jump Cut and Jump-Zoom Punch-In as named edits, each with its FFmpeg, HyperFrames and Remotion recipe

## Run it

A talking video with its pauses cut and punch-in zooms added, in one FFmpeg run on your machine.

1. Cut the silences and add the zooms in one run:

```bash
IN=input.mp4; OUT=edit.mp4; ZOOM=1.15; FACE=0.5
IFS=x read W H <<< "$(ffprobe -v error -select_streams v:0 -show_entries stream=width,height -of csv=p=0:s=x "$IN")"
DUR=$(ffprobe -v error -show_entries format=duration -of csv=p=0 "$IN")
GRAPH=$(ffmpeg -hide_banner -nostats -i "$IN" -af silencedetect=noise=-35dB:d=0.55 -f null - 2>&1 | awk -v dur="$DUR" -v pad=0.12 -v z="$ZOOM" -v f="$FACE" -v w="$W" -v h="$H" '
  function keep(a, b) {
    zoom = (n % 2) ? sprintf(",crop=iw/%s:ih/%s:(iw-ow)/2:(ih-oh)*%s,scale=%d:%d", z, z, f, w, h) : ""
    printf "[0:v]trim=%.3f:%.3f,setpts=PTS-STARTPTS%s,setsar=1[v%d];[0:a]atrim=%.3f:%.3f,asetpts=PTS-STARTPTS[a%d];", a, b, zoom, n, a, b, n
    labels = labels sprintf("[v%d][a%d]", n, n); n++
  }
  /silence_start/ { s = $NF + pad }
  /silence_end/ { e = $5 - pad; if (e > s) { if (s > prev + 0.05) keep(prev, s); prev = e } }
  END { if (dur > prev + 0.05) keep(prev, dur); printf "%sconcat=n=%d:v=1:a=1[v][a]", labels, n }')
ffmpeg -hide_banner -loglevel error -y -i "$IN" -filter_complex "$GRAPH" -map "[v]" -map "[a]" -c:v libx264 -crf 20 -c:a aac -b:a 192k "$OUT"
```

2. Check the result: the new length, then the number of pauses over 0.55 s left, which is 0 when the cut is clean. To tune it, change the first line and run it again: ZOOM is the punch-in on every other kept stretch (1 turns it off), FACE is where the eyes sit (0 is the top of the frame, 1 the bottom); d= is the shortest pause that is cut and pad the air kept on each side of a cut:

```bash
ffprobe -v error -show_entries format=duration -of csv=p=0 edit.mp4
ffmpeg -hide_banner -nostats -i edit.mp4 -af silencedetect=noise=-35dB:d=0.55 -f null - 2>&1 | grep -c silence_start
```

## Best skills for this

1. **Video editing skills for Claude Code and AI agents** (`varg-video-edit-library`, varg, live) — Start here: Jump Cut and Jump-Zoom Punch-In as named edits, each with its FFmpeg, HyperFrames and Remotion recipe
   - Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg`
   - Codex: `npx skills add vargHQ/skills --skill varg-video-edit-library -a codex -y`
   - Cursor: `npx skills add vargHQ/skills --skill varg-video-edit-library -a cursor -y`
   - Any agent, with the vargai CLI: `vargai install varg-video-edit-library`
   - Details: https://varg.ai/how-to/skills/varg-video-edit-library.md
2. **Herk Edit Kit** (`herk-edit-kit`, Nate Herk, live) — Alternative: Talking-head edits read from the transcript: silence and flub cuts, then motion graphics
   - Claude Code: `git clone https://github.com/nateherkai/herk-edit-kit.git`
   - Codex: `git clone https://github.com/nateherkai/herk-edit-kit.git`
   - Any agent, with the vargai CLI: `vargai install herk-edit-kit`
   - Details: https://varg.ai/how-to/skills/herk-edit-kit.md · Example: https://s3.varg.ai/how-to/previews/bb31cdd5a172/herk-edit-kit.mp4
3. **OpenMontage Silence Cutter & Auto Reframe** (`openmontage-jump-cut-reframe`, Calesthio, live) — Alternative: Automatic jump cuts from silencedetect, plus a face-tracked 16:9 to 9:16 reframe
   - Claude Code: `git clone https://github.com/calesthio/OpenMontage.git && cd OpenMontage && make setup`
   - Any agent, with the vargai CLI: `vargai install openmontage-jump-cut-reframe`
   - Details: https://varg.ai/how-to/skills/openmontage-jump-cut-reframe.md
4. **SmartCut (capcut-ai-editor)** (`capcut-smartcut-mcp`, mrbuslov, live) — Alternative: Cuts silences and duplicate takes inside your CapCut project, when you finish the edit there
   - Any MCP client: `pip install -e .  (inside the cloned repo), then add the venv python to your MCP config`
   - Any agent, with the vargai CLI: `vargai install capcut-smartcut-mcp`
   - Details: https://varg.ai/how-to/skills/capcut-smartcut-mcp.md
5. **FFmpeg Skill** (`ffmpeg-skill`, Shogo Kajiyama, live) — Alternative: 42 FFmpeg tools for agents with a machine-readable contract
   - Claude Code: `npx ffmpeg-skill`
   - Codex: `npx ffmpeg-skill --codex`
   - Cursor: `npx ffmpeg-skill --cursor`
   - Any agent, with the vargai CLI: `vargai install ffmpeg-skill`
   - Details: https://varg.ai/how-to/skills/ffmpeg-skill.md · Example: https://s3.varg.ai/how-to/previews/564622beb60d/ffmpeg-skill.mp4
6. **Short-form FFmpeg cookbook: copyable commands for Reels** (`short-form-ffmpeg-cookbook`, varg, live) — Adds: The next commands: crop to 9:16, burn captions, music under the voice
   - Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg`
   - Codex: `npx skills add vargHQ/skills --skill short-form-ffmpeg-cookbook -a codex -y`
   - Cursor: `npx skills add vargHQ/skills --skill short-form-ffmpeg-cookbook -a cursor -y`
   - Any agent, with the vargai CLI: `vargai install short-form-ffmpeg-cookbook`
   - Details: https://varg.ai/how-to/skills/short-form-ffmpeg-cookbook.md
7. **Caption Styles: 17 pro caption looks with presets** (`caption-styles`, varg, live) — Adds: Word-timed captions on the tightened cut
   - Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg`
   - Codex: `npx skills add vargHQ/skills --skill caption-styles -a codex -y`
   - Cursor: `npx skills add vargHQ/skills --skill caption-styles -a cursor -y`
   - OpenClaw: `npx clawhub@latest install caption-styles`
   - Gemini CLI: `npx skills add vargHQ/skills --skill caption-styles -a gemini-cli -y`
   - Any agent, with the vargai CLI: `vargai install caption-styles`
   - Details: https://varg.ai/how-to/skills/caption-styles.md · Example: https://s3.varg.ai/files/72c55813-c0fa-4cf2-9f64-ec4f7ed0e7ae/file_4d3d0dbdc222.mp4

## Ask the person first

Put these choices in front of the person before spending anything. Paste the example link next to each option: people pick a look by seeing it.

**How tight?**

- Light: only pauses over 0.8 s
- Standard: pauses over 0.55 s
- Tight jump cuts: pauses over 0.35 s

**Zoom?**

- Punch in to 115% on every other cut — [Jump-Zoom Punch-In](https://varg.ai/how-to/skills/jump-zoom-punch-in.md) · example: https://s3.varg.ai/how-to/previews/7121432ced16/take-jump-zoom-punch-in.mp4
- Stronger, 125% (best from a 4K source)
- No zoom, cuts only — [Jump Cut](https://varg.ai/how-to/skills/jump-cut.md) · example: https://s3.varg.ai/how-to/previews/c4027cc6cd21/take-jump-cut.mp4

**After the cut?**

- Word captions — [Caption Styles: 17 pro caption looks with presets](https://varg.ai/how-to/skills/caption-styles.md) · example: https://s3.varg.ai/files/72c55813-c0fa-4cf2-9f64-ec4f7ed0e7ae/file_4d3d0dbdc222.mp4
- AI b-roll over the jumps — [varg AI](https://varg.ai/how-to/skills/varg-ai.md) · example: https://s3.varg.ai/how-to/previews/7df061df8dcb/varg-ai.mp4
- Nothing, export

## How to cut silences and add zooms to a video: step by step

1. Check the take with ffprobe (size, frame rate, length) and never overwrite the source: every step writes a new file
2. Find the pauses from the audio, not from the transcript: silencedetect at -35 dB for 0.55 s or longer; on a noisy room raise the floor to -30 dB
3. One FFmpeg run: keep every stretch of speech with 0.12 s of air on each side, and scale every other kept stretch to 115% so each jump cut reads as a change of camera
4. Set FACE to where the eyes sit (0 is the top of the frame, 1 the bottom) so the zoom holds the eye line; stay at 130% or less on 1080p, past that the picture goes soft
5. Watch every join once with sound; a pause right before a number or a punchline is a beat, so bring it back by raising the minimum pause
6. Ums, retakes and flubs are not pauses: cut those from the transcript next (How to edit your own video footage), then captions and export

## Set up varg

varg is one API key for the models these skills drive — Seedance 2.5, Kling 4, Veo 3.1, Wan 3, Nano Banana 2.1, GPT Image 2.5, ElevenLabs v4 and 200+ more — billed in credits, with a cost estimate before anything runs.

- Any agent with a terminal: `curl -fsSL https://varg.ai/install | sh` (Windows: `irm https://varg.ai/install.ps1 | iex`), then `vargai login` and every model is a command — `vargai generate_video …`, `vargai estimate_cost …` (https://varg.ai/how-to/cli/)
- Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg` (skill + hosted MCP)
- Codex, Cursor, Gemini CLI, OpenClaw: `npx skills add vargHQ/skills --skill varg-ai -a <agent> -y`
- Grok and any agent that reads SKILL.md: `npx skills add vargHQ/skills --skill varg-ai`, or point it at the skill's SKILL.md
- Claude.ai, ChatGPT, any MCP client: connect `https://mcp.varg.ai/mcp`
- API key: https://varg.ai/dashboard/api · Model specs: https://varg.ai/models/llms.txt

## Related tutorials

- [How to edit a product video for TikTok and Reels with AI](https://varg.ai/how-to/edit-a-product-video-for-tiktok.md): Raw product footage (a creator clip, an unboxing, last month's winning ad) recut into a 9:16 ad: hook at second 0, no dead air, captions, one CTA, one file per hook.
- [How to cut a podcast into short video clips with AI](https://varg.ai/how-to/cut-a-podcast-into-short-video-clips.md): Find the best moments in a long video, cut them, reframe to 9:16 and burn captions.
- [How to turn photos into a slideshow video with AI](https://varg.ai/how-to/turn-photos-into-a-slideshow-video.md): Your photos cut to music, with motion, transitions on the beat and titles.
- [How to edit your own video footage with AI](https://varg.ai/how-to/edit-your-own-video-footage.md): Cut silences and flubs, reframe 16:9 to 9:16, add captions and b-roll to footage you shot.
- [How to make AI b-roll for your video](https://varg.ai/how-to/make-ai-b-roll-for-your-video.md): Cutaway footage for every mention in a voiceover or interview: generated clips, collage or stock-style shots, cut in on time.
- [How to change something inside a video with AI](https://varg.ai/how-to/change-something-inside-a-video.md): Swap a product, restyle a scene, change lighting or the look of an existing clip while keeping the motion.