@nomercy-entertainment/ffmpeg-static

Fetches the NoMercy FFmpeg fork binary for the current platform, on first use.

This is the fork the NoMercy MediaServer ships: custom muxers, AACS/BD+ decrypt, libass subtitle burn-in, and the codec set the product relies on. It is not stock ffmpeg — fixtures, transcodes, and probes produced with it match what the product produces in production. One package, so every CI action and every NoMercy library that needs ffmpeg resolves the same binary the same way.

Binaries come from the nomercy-ffmpeg GitHub releases. The package downloads the matching per-platform artifact, extracts it, caches it under the OS temp dir, and returns an absolute path.

Install

npm install @nomercy-entertainment/ffmpeg-static

Programmatic use

import { ensureFfmpeg, ensureFfprobe } from '@nomercy-entertainment/ffmpeg-static';

const ffmpeg = await ensureFfmpeg(); // absolute path, downloaded on first call
const ffprobe = await ensureFfprobe();

// then spawn it
import { spawnSync } from 'node:child_process';
spawnSync(ffmpeg, ['-version'], { stdio: 'inherit' });

ffmpegPath() and ffprobePath() are aliases for ensureFfmpeg() / ensureFfprobe(). Every call resolves the same cached path; only the first call downloads.

CLI use

The package installs two bins that print a resolved absolute path, so non-JS CI steps can capture the binary without writing any JavaScript:

FFMPEG=$(npx nomercy-ffmpeg-path)
FFPROBE=$(npx nomercy-ffprobe-path)

"$FFMPEG" -i input.mkv -c copy output.mp4

The path is printed to stdout; errors go to stderr with a non-zero exit code.

Environment overrides

| Variable | Effect | | --- | --- | | NOMERCY_FFMPEG | Absolute path to a pre-supplied ffmpeg. If it runs, it is returned as-is — no download. Use it to point at a CI cache or the MediaServer's bundled copy. | | NOMERCY_FFPROBE | Same, for ffprobe. | | NOMERCY_FFMPEG_VERSION | Override the pinned fork release tag (default v1.0.36). Lets CI bump the binary without a package release. | | NOMERCY_FFMPEG_FFVERSION | Override the upstream ffmpeg version in the asset name (default 8.1.1). |

Resolution order for each tool:

1. The NOMERCY_FFMPEG / NOMERCY_FFPROBE env var, if it points at a runnable binary.
2. A binary already cached from a previous run.
3. The matching platform artifact from the fork's GitHub release — downloaded, extracted, cached, and the archive cleaned up.

Supported platforms

| OS | Arch | Release artifact | | --- | --- | --- | | Windows | x64 | windows-x86_64.zip | | Linux | x64 | linux-x86_64.tar.gz | | Linux | arm64 | linux-aarch64.tar.gz | | macOS | arm64 | darwin-arm64.tar.gz | | macOS | x64 | darwin-x86_64.tar.gz |

On an unsupported platform, resolution throws with the supported list and a pointer to NOMERCY_FFMPEG. Set that env var to use a binary you supply.

License

MIT — see LICENSE in the repository root.