High-Volume Image Processor

Build a Node.js command-line tool that efficiently processes a large directory of images by generating multiple optimized variants of each image. The tool must process images in batches to maximize throughput and minimize memory usage.

Requirements

Input

• Accept a directory path containing source images (JPEG/PNG)
• Accept an output directory path for processed images
• Images should be at least 1920x1080 pixels

Output Variants

For each source image, generate three variants:

1. Thumbnail: 200px wide, maintaining aspect ratio
2. Medium: 800px wide, maintaining aspect ratio
3. Large: 1920px wide, maintaining aspect ratio

All variants should be:

• Saved as both WebP and JPEG formats
• Compressed with quality setting of 50
• Named using pattern: {original-name}-{size}.{ext} (e.g., photo-thumbnail.webp)

Performance Requirements

• Process multiple images concurrently (use available CPU cores minus 1)
• Generate all variants of a single source image together in one batch operation
• Display processing progress showing: current file, completed count, total count, elapsed time

Command-Line Interface

node process-images.js --input ./source-images --output ./optimized-images

Test Cases

• When processing a directory with 3 images, creates 18 output files (3 images × 3 sizes × 2 formats) @test
• When processing with 4 CPU cores available, uses concurrency of 3 @test
• Thumbnail variants are approximately 200px wide @test
• Output files include both .webp and .jpg extensions @test

Dependencies { .dependencies }

gatsby-plugin-sharp { .dependency }

Provides high-performance image processing capabilities with Sharp library integration.

@generates