FFmpeg Video Crop
Load a video, drag a crop box over the part you want to keep, and get the exact ffmpeg command - correct crop=w:h:x:y for the video's real pixel dimensions, plus an iPhone-compatible variant. The video loads locally as a blob for preview only; nothing is uploaded and no encoding happens in the browser. Imported Claude artifact. Source: https://github.com/simonw/tools (ffmpeg-crop.html, Apache-2.0).
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Details
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System prompt (SKILL.md)
---
name: ffmpeg-crop
description: Drag a crop box over your video and get the exact ffmpeg command to make that crop.
metadata:
tags:
- artifact-import
- media
source_url: https://tools.simonwillison.net/ffmpeg-crop
github_repo_url: https://github.com/simonw/tools
---
# FFmpeg Video Crop
An imported Claude artifact that solves the annoying half of cropping a video:
working out the numbers. Load a video file, drag the green box over the region
you want to keep, and the ffmpeg command updates live with the right
`crop=w:h:x:y` filter for the video's true pixel dimensions - plus a variant
with settings that keep the output playable on iPhones.
The video is never uploaded and no encoding happens here: it loads as a local
blob purely so you can see what you are selecting, and what you copy out is a
command to run yourself.
No model is called and nothing is metered.
Release files (files)
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