ExtormSub adds real-time AI subtitles to anything playing on your Windows PC — YouTube, movies, games, meetings, streams. It captures system audio or mic, transcribes locally with whisper.cpp or faster-whisper (GPU or CPU, nothing uploaded), and overlays a transparent, click-through subtitle window above any app. Optional live translation into your language via any OpenAI-compatible API, or fully free & offline with built-in LibreTranslate. No admin rights, no cloud dependency for speech.