Image Processing with Sharp

Sharp is a high-performance Node.js image processing library built on libvips.

Why Sharp?

Performance

• Fast: Up to 4x faster than ImageMagick
• Memory Efficient: Uses libvips streaming architecture
• Concurrent: Handles multiple operations efficiently

Features

• Resize, crop, and rotate images
• Format conversion (JPEG, PNG, WebP, etc.)
• Compression and optimization
• Metadata extraction

Implementation

Basic Operations

import sharp from 'sharp';

// Resize
await sharp(inputBuffer)
  .resize(800, 600)
  .toFile('output.jpg');

// Compress
await sharp(inputBuffer)
  .jpeg({ quality: 80 })
  .toBuffer();

// Crop
await sharp(inputBuffer)
  .extract({ left: 100, top: 100, width: 400, height: 300 })
  .toFile('cropped.jpg');

In The Workbench

Our file compressor uses Sharp for:

1. Image Compression: Reduce file sizes while maintaining quality
2. Format Conversion: Convert between JPEG, PNG, and WebP
3. Resizing: Adjust dimensions for optimization
4. Quality Control: Apply lossy or lossless compression

Compression Example

const compressed = await sharp(imageBuffer)
  .jpeg({ 
    quality: compressionLevel,
    mozjpeg: true // Better compression
  })
  .toBuffer();

Best Practices

1. Stream Processing: Use streams for large files
2. Batch Operations: Process multiple images concurrently
3. Format Selection: Choose appropriate formats (WebP for web, JPEG for photos)
4. Quality Balance: Find balance between file size and quality

Performance Tips

• Use toBuffer() for in-memory processing
• Leverage Sharp's built-in optimizations
• Cache processed images when possible
• Use appropriate quality settings for use case