Shisu-ko

Live Japanese subtitles for YouTube from a local Whisper server, scannable with Yomitan, mined into Anki with screenshot and audio.

Shisu-ko shows live Japanese subtitles on YouTube in Firefox and Chrome. A small server on your own computer transcribes the video's audio with OpenAI's Whisper a little ahead of where you are watching, and the extension draws the result over the player as ordinary page text. Nothing is sent to anyone: the server runs on your machine, and its only network traffic is fetching the video's audio from YouTube and the one-time model download. **What you get** - **Subtitles a few seconds after a video opens.** The server keeps transcribing ahead of the playhead and caches every line, so seeking back or rewatching is instant. Live streams work too. - **Text a dictionary can read.** Subtitles are real page text, so [Yomitan](https://yomitan.wiki/) or any popup dictionary scans them. Hovering a line pauses the video, the dictionary popup keeps it paused, and moving back over the video resumes it. - **A transcript panel** with every line so far. A timestamp jumps there, a pickaxe mines it. - **Sentence mining without pressing anything.** The moment Yomitan adds a card, Shisu-ko attaches a screenshot of the frame you were reading and an MP3 clip of the whole sentence, through AnkiConnect. The pickaxe on a line, or Alt+Shift+M, does the same on demand, into the newest card or into your Downloads folder. - **Your hardware, your model.** Whisper large-v3 by default on an NVIDIA GPU; one flag switches to the Japanese-specialised kotoba-whisper (about 6x faster) or to a small model on the CPU. **You need the companion server** The extension does nothing on its own. Download the server from the project page, start it, and the extension finds it at http://127.0.0.1:8790: - Windows: run `server\setup.cmd` once, then `server\run.cmd`. - Linux and macOS: `bash server/setup.sh` once, then `server/run.sh`. - Also available as a Nix flake and as a Docker image with GPU support. Requirements: Python 3.10 or newer, Node.js 20+ or Deno (yt-dlp needs a JavaScript runtime for YouTube), and an NVIDIA GPU with about 4 GB of free VRAM for large-v3; without a GPU, use a small model on the CPU. Optional: Yomitan for lookups, Anki with the AnkiConnect add-on for mining. **Shortcuts** - Alt+Shift+S turns Shisu-ko on or off (the switch in the popup header). - Alt+Shift+T toggles the transcript panel. - Alt+Shift+M mines the current sentence. - Left and Right jump to the previous or next subtitle (can be turned off). **Privacy** The extension talks only to the server on your own computer and, if you use mining, to Anki on your own computer. It has no account, no analytics and no remote code. The privacy policy on this page lists exactly what is exchanged with those two programs. Shisu-ko is free software under the MIT license. Source code, setup guide, server options and troubleshooting: https://github.com/Multysquid/shisu-ko