openclaw-voc-skill/claude-code/fmode-ffmpeg

fmode-ffmpeg

Claude Code skill + CLI that runs ffmpeg / ffprobe through a bundled static binary (ffmpeg-static / ffprobe-static). No system ffmpeg install required.

Run ffmpeg / ffprobe directly

# print the bundled binary paths
npx fmode-ffmpeg@latest which
npx fmode-ffmpeg@latest which-ffprobe

# run ffmpeg (everything after `--` is passed through)
npx fmode-ffmpeg@latest exec -- -y -i input.mp4 -ar 16000 -ac 1 out.wav

# run ffprobe
npx fmode-ffmpeg@latest probe -- -v quiet -print_format json -show_format input.mp4

# ffmpeg -version
npx fmode-ffmpeg@latest version

Install the Claude Code skill

# project-level → ./.claude/skills/fmode-ffmpeg
npx fmode-ffmpeg@latest workspace

# user-level → ~/.claude/skills/fmode-ffmpeg
npx fmode-ffmpeg@latest install

Then prompt Claude Code, e.g. 把 input.mp4 转成 16kHz 单声道 wav 音频。

Binary resolution order

1. FFMPEG_PATH / FFPROBE_PATH environment variable (if the file exists)
2. bundled static binary (ffmpeg-static / ffprobe-static)
3. ffmpeg / ffprobe on PATH

The bundled binary is verified before use (it is actually launched with -version). If ffmpeg-static's download was incomplete/corrupt, fmode-ffmpeg deletes it, clears the download cache, re-downloads once, and re-verifies; if it still won't run it falls back to system ffmpeg/FFMPEG_PATH with a clear hint.

• FMODE_FFMPEG_NO_REPAIR=1 — skip the auto re-download (fail fast to fallback).
• FMODE_FFMPEG_REPAIR_TIMEOUT_MS — bound the re-download (default 180000).

Windows / antivirus note

If you see not a valid Win32 application / EFTYPE, or the binary "works once then stops", antivirus (e.g. Windows Defender) may be quarantining or altering the downloaded ffmpeg.exe. The most reliable fix is to install ffmpeg yourself (or whitelist it) and point FFMPEG_PATH (and FFPROBE_PATH) at it — that path takes priority and skips the bundled download entirely.

Commands

Command	Description
which / which-ffprobe	print resolved binary path
exec -- <args> / run -- <args>	run ffmpeg with passthrough args
probe -- <args>	run ffprobe with passthrough args
version	ffmpeg -version
workspace / install	install the Claude Code skill
check / smoke / path	verify install / run smoke test / print target

License

MIT