TalkEdit/FFmpeg_COMPLIANCE.md

FFmpeg Compliance Checklist

Purpose: quick, practical checklist to ensure your TalkEdit distribution complies with FFmpeg licensing and packaging requirements.

1. Choose the FFmpeg build strategy

• Prefer an LGPL-only build (no GPL-only encoders) for minimal obligations.
• If you require GPL encoders (x264/x265/fdk-aac), document the decision and prepare to comply with GPL obligations.

2. Linking vs external binary

• Prefer spawning an external ffmpeg binary from Rust (invoke process) rather than statically linking FFmpeg into your app.
• If you link or bundle as a library, treat it as a third-party component and follow license terms strictly.

3. Bundling binary in installers

• If bundling ffmpeg binaries in installers, include the appropriate license files (COPYING.LGPL, COPYING.GPL) in the installer and app About/Legal.
• Include a plain-language notice in the installer/readme that explains which codecs/encoders are present and any implications.

4. Source & build-info disclosure

• For GPL components, you must provide access to the corresponding source or provide a written offer. Record the exact FFmpeg commit/configure flags used.
• Add a third_party/ffmpeg/BUILD_INFO.txt in the repo (or in release artifacts) containing:
  • FFmpeg git commit or version
  • configure flags used
  • date and builder identity (automated CI username)
  • link to the exact source tarball or repo snapshot

5. Make GPL components opt-in

• Default distribution: ship LGPL-only binary or no binary and invoke system ffmpeg when available.
• Offer an optional "codec pack" download or advanced installer that includes GPL encoders; make users explicitly accept terms before download.

6. Patent/licensing notice for codecs

• Add a short note in the README/installer explaining that certain codecs (H.264/AAC) may be patent-encumbered and that distributors may require separate licensing.

7. Platform-specific recommendations

• Linux: Prefer calling system FFmpeg (packaged by distro) or instruct users to install via package manager. If bundling, consider AppImage guidance.
• macOS: Prefer Homebrew/optional download; if bundling, include license files and sign/ notarize appropriately.
• Windows: If shipping ffmpeg.exe, include license files and a link to the source/build info; include checksums for shipped binaries.

8. Build automation & compliance artifacts

• Add a CI step that builds or fetches the FFmpeg binary, captures ffmpeg -buildconf, and writes BUILD_INFO.txt into the release artifacts.
• Produce a LICENSES folder in each installer containing FFmpeg license text and any third-party license texts used by your chosen build.

9. User-visible legal UI

• Add an About > Legal pane listing third-party components and linked license files.
• If downloading binaries on first run, show an explicit notice with a link to license and source information and require an OK from the user.

10. Pre-release legal checklist

• Verify whether chosen build enables GPL libraries; if yes, prepare source or written offer before publishing.
• Ensure installer contains license files and links to source/build-info.
• Add a short FAQ entry about codec patents and user options.

Notes & Next Steps

• This checklist is practical guidance, not legal advice. For final release compliance, consult legal counsel experienced in open-source licensing.
• I can add a small CI script snippet that records ffmpeg -buildconf and uploads BUILD_INFO.txt to release assets — tell me which CI you use and I'll draft it.