Offspring is a tiny cross-platform app (Windows 11 + macOS) that adds
video/image conversion shortcuts to your right-click menu. Drop a .mov
on a shortcut, get a trimmed-down .mp4 or a Discord-ready .gif in
the same folder. No windows to open, no command lines, no upload to a
web service.
- Ships a classic right-click submenu on every video and image (always on) — one click per preset.
- Optionally populates your Send to menu.
- Optionally integrates with the Windows 11 modern right-click menu (top-level, no "Show more options") via a signed sparse MSIX package.
- Manages a curated list of presets — GIFs for Discord, compressed MP4s, cropped 9:16 verticals, 1080p downscales — that you can freely edit, reorder, and add to from the Presets tab. Every preset can set its own crop, max file size, palette, and dither for GIFs.
- Streams per-file progress in a small always-on-top window while FFmpeg does the work.
Grab the latest installer from the Releases page:
- Windows:
Offspring-Setup-<version>.exe(Standard) orOffspring-Studio-Setup-<version>.exe(no-network variant — see SECURITY.md). Standard is a per-user install; no admin prompt unless you're upgrading from a pre-0.4.4 per-machine build. - macOS:
Offspring_<version>_universal.dmg. Drag to Applications. Signed + notarized; Gatekeeper allows it on first launch. To enable the Finder right-click integration, after first launch open System Settings → Keyboard → Keyboard Shortcuts → Services → Files and Folders and tick Offspring….
On first launch, Offspring downloads an FFmpeg build into the per-user
data folder if one isn't already on PATH — BtbN's static GPL build on
Windows (~160 MB to %LOCALAPPDATA%\Offspring\ffmpeg\), evermeet.cx's
universal static build on macOS (to
~/Library/Application Support/Offspring/ffmpeg/).
You can also point the app at a pre-existing FFmpeg install from the
Settings tab (e.g. /opt/homebrew/bin/ffmpeg for a Homebrew install).
Updates: Offspring never pings GitHub on its own. It only checks for updates when you click Settings → Check for updates, and even then it just shows a banner — the new installer doesn't download until you click "Download" in that banner. Every installer is signed offline with an Ed25519 minisign key whose public counterpart is pinned in the binary; the in-app updater verifies the signature against that key and refuses to launch any installer whose signature is missing or doesn't match. See SECURITY.md and THREAT_MODEL.md for the full picture.
Offspring does not bundle FFmpeg. It invokes whatever FFmpeg lives in
its per-user data folder (downloaded on demand —
%LOCALAPPDATA%\Offspring\ffmpeg\ on Windows,
~/Library/Application Support/Offspring/ffmpeg/ on macOS) or the path
you configured in Settings. FFmpeg is © the FFmpeg developers, licensed
under the LGPL v2.1+, and its source
is available at https://ffmpeg.org/download.html.
Because Offspring calls FFmpeg as a separate executable (no linking), the LGPL does not propagate to Offspring's own code. Offspring itself is MIT.
Full third-party attributions live in NOTICE.md.
Offspring makes no analytics, telemetry, or phone-home calls. The app makes zero outbound requests on its own — every network call is explicitly user-initiated:
- GitHub Releases update check when you click Settings → Check for updates.
- Installer download when you click Download in the update banner that follows.
- FFmpeg download when you click Download FFmpeg on first run (or any time later if you uninstall FFmpeg).
Full inventory in SECURITY.md → Privacy / network connections.
MIT © 2026 Second March.