Right-click convert videos & images with FFmpeg — from anywhere in Windows.
Offspring is a tiny Windows 11 app 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.
Grab the latest Offspring-Setup-<version>.exe from the
Releases page and run
it. The installer is admin-only — that keeps every install in the same scope
(no stacked per-user + machine copies) and lets it trust the shell-extension
signing cert so the modern Windows 11 menu toggle works without prompts.
On first install, Offspring offers to download the LGPL essentials FFmpeg
build (~80 MB) into %LOCALAPPDATA%\Offspring\ffmpeg\. You can also point
the app at a pre-existing FFmpeg install from the Settings tab.
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
%LOCALAPPDATA%\Offspring\ffmpeg\ (downloaded on demand) 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:
Full inventory in SECURITY.md → Privacy / network connections.
MIT © 2026 Second March.