MuJing (幕境) — Learn English Vocabulary Through Movies and Real Context

MuJing (幕境) is a free, open-source desktop app that lets you learn English vocabulary through movies, TV shows, and documents. Instead of memorizing isolated word lists, you encounter words in their original narrative context — the scene where they were actually used — making vocabulary stick far more naturally.

Why Context Beats Flashcards

Traditional vocabulary apps show you a word and a definition. MuJing shows you the word inside the movie scene where it appeared — with audio, subtitles, and visual context. Research consistently shows that words learned in context are retained 2-3x longer than words learned in isolation.

The key insight: you’re not studying English — you’re watching content you enjoy, and learning happens as a side effect.

How It Works

┌─────────────┐     ┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│  Load Media  │ ──▶ │  Generate   │ ──▶ │  Study with  │ ──▶ │  Watch with  │
│  (MKV/SRT/   │     │  Word Bank  │     │  Context     │     │  Danmaku     │
│   PDF/TXT)   │     │             │     │  Spelling    │     │  Review      │
└─────────────┘     └─────────────┘     └─────────────┘     └─────────────┘

1. Select your content — import an MKV video, subtitle file, PDF, or text document
2. Generate a word bank — MuJing extracts vocabulary and tags frequency levels (CET-4, CET-6, GRE, etc.)
3. Study in context — each word shows its original scene, pronunciation, definition, and example sentences
4. Watch with danmaku — during playback, studied words float across the screen as subtitle overlays for passive review

Key Features

Supported Input Formats

Video Player Controls

The built-in player is designed for language learners:

• Auto-pause after each subtitle line — practice shadowing (repeating what you hear)
• A/D keys — navigate between subtitle segments
• S key — repeat current segment
• Click any word — instant dictionary lookup + add to word bank

Installation

Available for Windows and macOS. Download from GitHub Releases — one-click installer packages available for both platforms.

Built with Kotlin (99.8%) + Compose Desktop. Open source under GPL-3.0. 3,800+ GitHub stars.

Practical Workflow Example

Want to learn English from Spider-Man?

1. Load the MKV file → MuJing extracts all dialogue
2. Filter to words at your level (e.g., CET-4 vocabulary)
3. Study each word with its movie clip: “I’m getting better. It was not magic.”
4. Practice spelling while the clip replays
5. Watch the full movie — your studied words appear as floating danmaku reminders

Compared to Other Tools

MuJing’s advantage: you use your own content, it works completely offline, and it’s free. The tradeoff is it’s desktop-only and requires you to source your own media.

How LearnAI Team Could Use This

• Language-learning demos — Use MuJing to show how authentic media becomes structured vocabulary practice.
• AI education examples — Compare context-rich study workflows against isolated flashcard memorization.
• Workshop activities — Have learners import a short clip, extract vocabulary, and build a study routine.
• Curriculum design — Adapt the contextual-learning pattern for other subjects where examples matter more than definitions.

Real-World Use Cases

• English learners studying vocabulary from movies, TV shows, and subtitles they enjoy.
• Teachers preparing vocabulary lists from assigned videos or reading materials.
• Self-study students practicing listening, spelling, and review offline on desktop.
• Exam prep learners filtering extracted words by CET-4, CET-6, GRE, or core vocabulary levels.