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.
npx skills add xuansenpa1/skillrevise --skill ffmpeg-audio-processinggit clone --depth 1 https://github.com/xuansenpa1/skillreviseWrote 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.
[](https://agentmods.dev/skills/xuansenpa1/skillrevise/ffmpeg-audio-processing)<a href="https://agentmods.dev/skills/xuansenpa1/skillrevise/ffmpeg-audio-processing"><img src="https://agentmods.dev/badge/skills/xuansenpa1/skillrevise/ffmpeg-audio-processing/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.
<a href="https://agentmods.dev/skills/xuansenpa1/skillrevise/ffmpeg-audio-processing"><img src="https://agentmods.dev/badge/skills/xuansenpa1/skillrevise/ffmpeg-audio-processing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00020 | $0.01266 |
| Opus 5 | $0.00010 | $0.00633 |
| Sonnet 5 | $0.00004 | $0.00253 |
| Haiku 4.5 | $0.00002 | $0.00127 |
Grade A, and why
FFmpeg Audio Processing 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 8d 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.
This is a copy
100% identical to ffmpeg-audio-processing — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 168 lines — stays where its author put it; the contents beside it link to each section on GitHub.
FFmpeg Audio Processing Skill
Extract, normalize, mix, and process audio tracks from video files.
When to Use
- Extract audio from video
- Normalize audio levels
- Mix multiple audio tracks
- Convert audio formats
- Extract specific channels
- Adjust audio volume
Extract Audio
# Extract as MP3
ffmpeg -i video.mp4 -vn -acodec libmp3lame -q:a 2 audio.mp3
# Extract as AAC (copy, no re-encode)
ffmpeg -i video.mp4 -vn -c:a copy audio.aac
# Extract as WAV (uncompressed)
ffmpeg -i video.mp4 -vn -acodec pcm_s16le audio.wav
# Extract specific audio stream
ffmpeg -i video.mp4 -map 0:a:1 -c:a copy audio2.aac
Normalize Audio
# Normalize loudness (ITU-R BS.1770-4)
ffmpeg -i input.mp4 -af "loudnorm=I=-23:TP=-1.5:LRA=11" output.mp4
# Simple normalization
ffmpeg -i input.mp4 -af "volume=2.0" output.mp4
# Peak normalization
ffmpeg -i input.mp4 -af "volumedetect" -f null -
# Then use the detected peak to normalize
ffmpeg -i input.mp4 -af "volume=0.5" output.mp4
Volume Adjustment
# Increase volume by 6dB
ffmpeg -i input.mp4 -af "volume=6dB" output.mp4
# Decrease volume by 3dB
ffmpeg -i input.mp4 -af "volume=-3dB" output.mp4
# Set absolute volume
ffmpeg -i input.mp4 -af "volume=0.5" output.mp4
Channel Operations
# Extract left channel
ffmpeg -i stereo.mp3 -map_channel 0.0.0 left.mp3
# Extract right channel
ffmpeg -i stereo.mp3 -map_channel 0.0.1 right.mp3
# Convert stereo to mono
ffmpeg -i stereo.mp3 -ac 1 mono.mp3
# Convert mono to stereo
ffmpeg -i mono.mp3 -ac 2 stereo.mp3
Mix Audio Tracks
# Replace audio track
ffmpeg -i video.mp4 -i audio.mp3 -c:v copy -map 0:v:0 -map 1:a:0 output.mp4
# Mix two audio tracks
ffmpeg -i video.mp4 -i audio2.mp3 \
-filter_complex "[0:a][1:a]amix=inputs=2:duration=first" \
-c:v copy output.mp4
# Mix with volume control
ffmpeg -i video.mp4 -i bgm.mp3 \
-filter_complex "[0:a]volume=1.0[voice];[1:a]volume=0.3[music];[voice][music]amix=inputs=2:duration=first" \
-c:v copy output.mp4
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.
- 8d ago First seen · 168 lines · 20 tokens per session scan A 1bd65ef43995
FFmpeg Audio Processing is a skill published in the GitHub repository xuansenpa1/skillrevise (56 stars, last pushed 6d ago), licensed MIT. It adds 20 tokens to every session and 1,266 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to ffmpeg-audio-processing, differing in 2 lines, and is treated as a copy.
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