genesys-ffmpeg-minimal

Minimal static ffmpeg builds for the Genesys SDK MP3 asset baker. Produces a small CLI that transcodes loose audio in .dist to MP3 (WAV / FLAC / AIFF / OGG / AAC / M4A → MP3 via libmp3lame).

Build scripts in this repo are MIT. Published binaries are GPL-2.0-or-later (FFmpeg) and LGPL-2.0-or-later (LAME). See RECIPE.md.

Why a separate repo?

• Full BtbN ffmpeg builds are ~130 MB; this recipe targets ~5–15 MB.
• GPL/LAME native builds are slow and platform-specific — keep them out of the monorepo.
• Genesys pins a release tag + SHA256 from here in vendor:ffmpeg.

Layout

configure-flags.sh     # shared ./configure recipe (Genesys scope)
VERSION                # line 1: ffmpeg version, line 2: recipe revision
scripts/
  build-windows-mingw.sh   # MSYS2 MinGW64 — primary path
  build-linux-gnu.sh       # glibc static
  build-macos.sh             # stub (phase 2)
  build-lame.sh / build-ffmpeg.sh
  package.sh / smoke-test.sh
fixtures/                # WAV fixture + generator
.github/workflows/       # CI + release

Inspired by wo80/ffmpeg-audio-only configure patterns and BtbN/FFmpeg-Builds LAME linkage — not a fork; recipe is trimmed to Genesys inputs only.

Local build (Windows + MSYS2 MinGW64)

1. Open MSYS2 MinGW 64-bit.

2. Install toolchain:

   pacman -S --needed mingw-w64-x86_64-{gcc,make,pkg-config,nasm,yasm} zip curl python

3. From repo root:

   bash ./scripts/build-windows-mingw.sh

4. Output: dist/genesys-ffmpeg-minimal-<ffmpeg>-r<recipe>-win64-static.zip containing bin/ffmpeg.exe and VERSION.txt.

CI

• CI (push/PR): builds win64-static + linux64-static, runs smoke test.
• Release (tag v* or manual): uploads both archives to GitHub Releases.

Smoke test

bash ./scripts/smoke-test.sh artifacts/win64-static/bin/ffmpeg.exe

Genesys integration (monorepo)

After a release is published:

1. Pin tag + checksum in packages/sdk/scripts/vendor-ffmpeg.ts.
2. Download genesys-ffmpeg-minimal-*-win64-static.zip → vendor/ffmpeg/win32-x64/bin/.
3. Run pnpm --filter @gnsx/genesys.sdk test -- test/mp3-audio-compiler.integration.test.ts.

Roadmap

• First green CI on main
• Tag v0.1.0 with measured binary sizes in release notes
• macOS arm64/x64 jobs
• linux-arm64
• Wire Genesys vendor-ffmpeg.ts to this repo (replace BtbN)

Bump checklist

When changing configure-flags.sh:

1. Increment recipe version (line 2 of VERSION).
2. Re-run smoke tests on all platforms.
3. Tag a new release; bump pin in Genesys monorepo.