PDF-Shrinker

A command-line tool to compress PDF files while maintaining reasonable quality.

Overview

PDF-Shrinker is a Node.js command-line utility that leverages Ghostscript to compress PDF files efficiently. It offers multiple compression levels, allowing you to balance file size reduction with output quality based on your specific needs.

Features

• 🗜️ Multiple compression levels (from light to maximum)
• 📊 Real-time progress tracking
• 📏 Detailed compression statistics (before/after sizes, ratio)
• 🎮 Simple command-line interface
• 🚀 Fast processing
• 📝 Verbose mode for debugging

Prerequisites

• Node.js (version 12 or later)
• Ghostscript (must be installed and available in your PATH)

Installation

Local Installation

# Clone the repository
git clone https://github.com/msoltanov/pdf-shrinker.git
cd pdf-shrinker

# Install dependencies
npm install

# Make the script executable
chmod +x index.js

Manual Package Installation (Offline)

For offline/manual installation, download the following .tgz packages from the npm registry:

1. Download these packages from npmjs.com:

   • https://registry.npmjs.org/chalk/-/chalk-4.1.2.tgz
   • https://registry.npmjs.org/cli-progress/-/cli-progress-3.12.0.tgz
   • https://registry.npmjs.org/commander/-/commander-13.1.0.tgz

2. Copy the downloaded .tgz files to your project directory

3. Install each package manually:

npm install ./chalk-4.1.2.tgz
npm install ./cli-progress-3.12.0.tgz
npm install ./commander-13.1.0.tgz

Note: Some packages might have dependencies that need to be installed separately. Check package.json inside each .tgz file for required dependencies.

Verify Ghostscript Installation

Ensure Ghostscript is installed by running:

gs --version

If not installed, you can install it using:

• Ubuntu/Debian: sudo apt-get install ghostscript
• macOS: brew install ghostscript
• Windows: Download from Ghostscript website

Usage

Basic Usage

pdf-shrinker -i input.pdf -o output.pdf

If installed locally, run:

./index.js -i input.pdf -o output.pdf

Command Line Options

Option	Description
-i, --input <file>	Input PDF file (required)
-o, --output <file>	Output PDF file (optional, defaults to input-compressed.pdf)
-l, --level <1-5>	Compression level (optional, defaults to 3)
-v, --verbose	Show detailed processing information
-h, --help	Display help information

Compression Levels

PDF-Shrinker offers four compression levels:

Level 1: Light Compression

• Best quality output
• Minimal file size reduction
• Ideal for: Documents with many high-quality images that must remain high-resolution

Level 2: Lower Compression

• Good quality output
• Moderate file size reduction
• Ideal for: General purpose documents with mixed content

Level 3: Medium Compression (default)

• Average quality but still acceptable for most purposes
• Significant file size reduction
• Ideal for: Documents that need to be emailed or stored with limited space

Level 4: Higher Compression

• Reduced quality but still acceptable for most purposes
• Significant file size reduction
• Ideal for: Documents that need to be emailed or stored with limited space

Level 5: Maximum Compression

• Lowest quality
• Maximum file size reduction
• Ideal for: Archiving, when file size is critical and some quality loss is acceptable

Examples

Basic Compression (Level 3)

pdf-shrinker -i large-document.pdf -o compressed-document.pdf

Light Compression with Highest Quality (Level 1)

pdf-shrinker -i large-document.pdf -o high-quality-compressed.pdf -l 1

Maximum Compression with Lowest Quality (Level 5)

pdf-shrinker -i large-document.pdf -o max-compressed.pdf -l 5

Verbose Mode for Debugging

pdf-shrinker -i large-document.pdf -o compressed-document.pdf -v

Performance Results

Based on testing, you can expect approximately:

• Level 1: 20-40% reduction in file size
• Level 2: 40-60% reduction in file size
• Level 3: 60-70% reduction in file size
• Level 4: 70-80% reduction in file size
• Level 5: 80-95% reduction in file size

Actual results may vary depending on the content of your PDF files.

Troubleshooting

Common Issues

• "Command not found": Ensure the tool is installed globally or you're running from the correct directory
• "Ghostscript not found": Make sure Ghostscript is installed and added to your PATH
• "Permission denied": Make sure the script is executable (chmod +x index.js)
• "Error: Input file not found": Check that the input file path is correct

Getting Help

If you encounter any issues, please:

1. Run in verbose mode (-v) to see detailed information
2. Check that Ghostscript is properly installed
3. Ensure you have read/write permissions for the input and output locations

License

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

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.