🎬 SubtitleAI-Pro-Extension - YouTube Subtitle Generator

An AI-powered YouTube subtitle generator that uses OpenAI's Whisper model to automatically transcribe videos in any language to English subtitles. This project consists of a Python Flask backend server and a Chrome extension that seamlessly integrates with YouTube to generate high-quality subtitles.

✨ Features

• 🤖 AI-Powered Transcription: Uses OpenAI's Whisper model for accurate speech-to-text conversion
• 🌍 Multi-Language Support: Transcribes videos in any language and translates to English
• ⚡ Real-Time Processing: Fast subtitle generation with multiple model size options
• 🎯 Browser Integration: Chrome extension automatically detects YouTube videos
• 📁 Easy Export: Download subtitles in standard SRT format
• 🚀 One-Click Operation: Generate subtitles with a single button click
• 🎨 Modern UI: Clean, intuitive interface with real-time status updates

🏗️ Project Structure

SubtitleAI-Pro-Extension/
├── 📁 Extension/                # Chrome Extension
│   ├── manifest.json           # Extension configuration
│   ├── popup.html             # Extension popup interface
│   ├── popup.js               # Extension popup logic
│   ├── content.js             # YouTube page integration
│   ├── background.js          # Background service worker
│   ├── styles.css             # Extension styling
│   └── 📁 icons/              # Extension icons
├── 📁 downloads/              # Temporary audio files
├── 📁 Preview/                # Screenshots of the application
├── gen.py                     # Core subtitle generation logic
├── server.py                  # Flask backend server
├── requirements.txt           # Python dependencies
└── README.md                  # This file

🛠️ Technology Stack

Backend

• Python 3.8+: Core programming language
• Flask: Web framework for API server
• Flask-CORS: Cross-origin resource sharing
• faster-whisper: Optimized Whisper implementation
• pytubefix: YouTube video downloading
• OpenAI Whisper: AI transcription model

Frontend

• Chrome Extension API: Browser integration
• JavaScript ES6+: Extension logic
• HTML5/CSS3: User interface
• Chrome Manifest V3: Modern extension framework

📋 Prerequisites

Before you begin, ensure you have the following installed:

• Python 3.8 or higher
• pip (Python package installer)
• Google Chrome browser
• Internet connection (for downloading Whisper models)

🚀 Quick Start

Step 1: Clone the Repository

git clone SubtitleAI-Pro-Extension
cd SubtitleAI-Pro-Extension

Step 2: Set Up Python Environment

# Create virtual environment (recommended)
python -m venv Sub
cd Sub
Scripts\activate  # On Windows

# Install dependencies
pip install -r requirements.txt

Step 3: Start the Backend Server

python server.py

You should see:

🚀 Starting YouTube Subtitle Generator Server...
📡 Server will run on http://localhost:5000
🎬 Ready to generate subtitles!
--------------------------------------------------
 * Running on http://localhost:5000

Step 4: Install Chrome Extension

1. Open Google Chrome
2. Navigate to chrome://extensions/
3. Enable "Developer mode" (toggle in top-right corner)
4. Click "Load unpacked"
5. Select the Extension folder from this project
6. The extension icon should appear in your Chrome toolbar

Step 5: Generate Subtitles

1. Navigate to any YouTube video
2. Click the SubtitleAI-Pro-Extension icon
3. Select your preferred model size:
   • Tiny: Fastest, lower accuracy
   • Base: Good balance (recommended)
   • Small: Better accuracy
   • Medium: High accuracy
   • Large: Best accuracy, slower
4. Click "Generate Subtitles"
5. Wait for processing to complete
6. Download the generated SRT file

🎛️ Model Sizes & Performance

Model	Size	Speed	Accuracy	Use Case
Tiny	~39 MB	⚡⚡⚡⚡⚡	⭐⭐⭐	Quick previews
Base	~74 MB	⚡⚡⚡⚡	⭐⭐⭐⭐	Recommended
Small	~244 MB	⚡⚡⚡	⭐⭐⭐⭐	Better quality
Medium	~769 MB	⚡⚡	⭐⭐⭐⭐⭐	High accuracy
Large	~1550 MB	⚡	⭐⭐⭐⭐⭐	Best quality

🔧 Configuration

Server Configuration

The server runs on http://localhost:5000 by default. To change this, modify server.py:

app.run(host='localhost', port=5000, debug=False)

Extension Configuration

The extension is configured to connect to localhost:5000. To change the server URL, modify the serverUrl in Extension/popup.js:

const serverUrl = 'http://localhost:5000';

📖 API Documentation

Generate Subtitles Endpoint

POST /generate-subtitles

Request Body:

{
  "url": "https://www.youtube.com/watch?v=VIDEO_ID",
  "model_size": "base"
}

Response:

{
  "success": true,
  "srt_content": "1\n00:00:00,000 --> 00:00:05,000\nHello, welcome to this video...\n\n",
  "video_title": "Sample Video Title",
  "subtitle_count": 42
}

Health Check Endpoint

GET /health

Response:

{
  "status": "healthy",
  "message": "Subtitle generator server is running"
}

🐛 Troubleshooting

Common Issues

1. "Server not responding" error

   • Ensure the Python server is running on port 5000
   • Check if another application is using port 5000
   • Verify firewall settings

2. "Failed to download audio" error

   • Check internet connection
   • Verify the YouTube URL is valid and accessible
   • Some videos may be restricted or private

3. Slow processing

   • Use a smaller model size (tiny/base)
   • Ensure adequate RAM (4GB+ recommended)
   • Close unnecessary applications

4. Extension not working

   • Refresh the YouTube page
   • Reload the extension in Chrome
   • Check browser console for errors

Performance Tips

• Use SSD storage for faster model loading
• Close unnecessary tabs to free up memory
• Use base model for best speed/accuracy balance
• Ensure stable internet for smooth downloads

🤝 Contributing

We welcome contributions! Please follow these steps:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• OpenAI for the Whisper model
• pytube developers for YouTube download capabilities
• Flask team for the excellent web framework
• Chrome Extension community for documentation and examples

📞 Support

If you encounter any issues or have questions:

1. Check the Troubleshooting section
2. Search existing GitHub Issues
3. Create a new issue with detailed information
4. Include error messages and system information

🚀 Roadmap

Upcoming Features

• Multiple language output support
• Batch processing for multiple videos
• Subtitle editing interface
• Auto-sync with video timing
• Cloud deployment option
• Firefox extension support

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Made with ❤️ by RajM012

Transform any YouTube video into accessible content with AI-powered subtitles!