What is ffmpeg-toolkit?

An agent for creating or improving GitHub community files, which are repository documents that guide bug reports, feature requests, pull requests, ownership, and contribution rules.

Use it to generate issue templates, a pull-request template, CODEOWNERS, labels, and other files in the repository's .github directory.

It gives contributors consistent forms and instructions, making project issues easier to report, review, and maintain.

ffmpeg-toolkit — Skill for Claude Code and Codex by jakenuts

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add jakenuts/agent-skills --skill ffmpeg-toolkit

Clone the repo

git clone --depth 1 https://github.com/jakenuts/agent-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/jakenuts/agent-skills/ffmpeg-toolkit/github.svg)](https://agentmods.dev/skills/jakenuts/agent-skills/ffmpeg-toolkit)

Your own site

<a href="https://agentmods.dev/skills/jakenuts/agent-skills/ffmpeg-toolkit"><img src="https://agentmods.dev/badge/skills/jakenuts/agent-skills/ffmpeg-toolkit/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/jakenuts/agent-skills/ffmpeg-toolkit"><img src="https://agentmods.dev/badge/skills/jakenuts/agent-skills/ffmpeg-toolkit.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,991 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00060	$0.02991
Opus 5.5	$0.00024	$0.01196
Sonnet 5.5	$0.00012	$0.00598
Haiku 4.5	$0.00006	$0.00299

Measured 2mo ago against content hash f385febeb1a5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

ffmpeg-toolkit scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/ffmpeg-toolkit/SKILL.md · 271 lines

How it starts

The opening of the file, as written. The whole thing — 271 lines — stays where its author put it; the contents beside it link to each section on GitHub.

FFmpeg Toolkit

Transcode

# Convert to MP4 (H.264 + AAC)
ffmpeg -i input.mov -c:v libx264 -preset medium -crf 23 \
       -c:a aac -b:a 128k output.mp4

# Convert to WebM (VP9 + Opus)
ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 \
       -c:a libopus -b:a 128k output.webm

Resize

# Specific dimensions
ffmpeg -i input.mp4 -vf "scale=1920:1080" output.mp4

# Aspect-ratio preserve with padding (letterbox/pillarbox)
ffmpeg -i input.mp4 -vf "scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2" output.mp4

# Crop to fill (no black bars)
ffmpeg -i input.mp4 -vf "scale=1920:1080:force_original_aspect_ratio=increase,crop=1920:1080" output.mp4

# Scale to width, auto height
ffmpeg -i input.mp4 -vf "scale=1280:-2" output.mp4

# Scale to percentage (50%)
ffmpeg -i input.mp4 -vf "scale=iw/2:ih/2" output.mp4

Trim and Cut

# Cut from timestamp + duration (re-encode recommended for accuracy)
ffmpeg -i input.mp4 -ss 00:00:30 -t 00:00:15 -c:v libx264 -c:a aac output.mp4

# Cut from start to end timestamp
ffmpeg -i input.mp4 -ss 00:00:30 -to 00:00:45 -c:v libx264 -c:a aac output.mp4

# Stream copy (faster, but may lose frames at non-keyframe cut points)
ffmpeg -i input.mp4 -ss 00:00:30 -t 00:00:15 -c copy output.mp4

# Fast seek for large files (put -ss before -i)
ffmpeg -ss 00:10:00 -i large_video.mp4 -t 00:05:00 -c copy clip.mp4

Note: Re-encoding is recommended for trimming. Stream copy (-c copy) can silently drop video if the seek point doesn't align with a keyframe.

Speed Adjustment

# 2x speed (video and audio)
ffmpeg -i input.mp4 -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" \
       -map "[v]" -map "[a]" output.mp4

# 0.5x speed (slow motion)
ffmpeg -i input.mp4 -filter_complex "[0:v]setpts=2.0*PTS[v];[0:a]atempo=0.5[a]" \
       -map "[v]" -map "[a]" output.mp4

# Video only (no audio)
ffmpeg -i input.mp4 -filter:v "setpts=0.5*PTS" -an output.mp4

# Extreme slow motion (0.25x) - chain atempo filters (each limited to 0.5-2.0)
ffmpeg -i input.mp4 -filter_complex "[0:v]setpts=4.0*PTS[v];[0:a]atempo=0.5,atempo=0.5[a]" \
       -map "[v]" -map "[a]" output.mp4

Read the full file on GitHub · 271 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 271 lines · 60 tokens per session scan A f385febeb1a5

Subscribe to this mod's changes

ffmpeg-toolkit is a skill published in the GitHub repository jakenuts/agent-skills (2 stars, last pushed 3mo ago), licensed MIT. It adds 60 tokens to every session and 2,991 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Git and workflow Writing and docs

ffmpeg-toolkit next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
ffmpeg-toolkitjakenuts/agent-skills	Skill	2	3mo ago	MIT	A	60	Claude Code, Codex
merge-batchdiegosouzapw/OmniRoute	Skill	83k	6d ago	MIT	A	46	Claude Code
prowler-commitprowler-cloud/prowler	Skill	15k	today	Apache-2.0	A	44	Claude Code, Codex
gh-auth-isolationgithub/gh-aw	Skill	5.6k	today	MIT	A	20	Claude Code, Codex
comet-githubrpamis/comet	Skill	3.3k	yesterday	MIT	A	72	Claude Code, Codex
github-skillzeenie-ai/OpenCompany	Skill	1.1k	2d ago	MIT	A	51	Claude Code
release-helperSahir619/fable-method	Skill	2.3k	1mo ago	MIT	A	43	Claude Code