Nexo

A blazing-fast, lightweight single static binary to convert images from JPG, PNG formats to Webp

Features

• Lightning Fast - Converts 30 .jpg (Dimensions: 5120 × 2880) images to .webp within 10s
• Ultra Lightweight - Single ~5MB binary, no external dependencies
• Zero Config - Just run and forget
• Multiple Formats - Supports JPG, JPEG, PNG
• Auto-Cleanup - Automatically deletes original images after conversion
• Cross-Platform - Works on macOS, Linux, and Windows

More aren't planned but feel free to add them yourself.

How It Works

1. Scan - Recursively scans the input directory for supported image formats
2. Queue - Creates a work queue with all found images
3. Process - Uses a worker pool (up to 8 concurrent workers) to convert images in parallel
4. Encode - Uses the high-performance gen2brain/webp library for WebP encoding
5. Cleanup - Removes original images after successful conversion
6. Exit - Automatically exits when all conversions are complete

Real-World Test Results

High-Resolution Batch Conversion:

• Images: 30 JPEG files
• Total Size: 313MB
• Per Image: 10.8MB, 5120 × 2880 pixels (5K resolution)
• Completion Time: 9.34 seconds
• Result: 30 high-resolution images converted to WebP in under 10s

Installation

Prerequisites

• Go 1.26+ (for building from source)
• Task (optional, for using Taskfile)

Quick Install

# Clone the repository
git clone <repository-url>
cd imgconverter

# Build the binary
task build

# Or with go directly
go build -o build/imgconverter -ldflags="-s -w" .

Usage

Basic Usage

1. Create a converter/ folder in the same directory as the binary
2. Put your images inside the folder
3. Run the binary:

./build/imgconverter

4. Done! All images are converted to .webp in the same directory and originals are removed

Custom Directory

You can specify a different input directory:

./build/imgconverter /path/to/your/images

Example Output

Success:

Found 42 image(s) to convert
Conversion completed!
Successful: 42
Time taken: 850ms

With Failures:

Found 50 image(s) to convert
Conversion completed!
Successful: 45
Failure: 5
Failed Images: corrupt1.png, corrupt2.jpg, missing.png, bad.png, error.jpg
Time taken: 1.23s

Building

Build for Current Platform

task build

Build for All Platforms

task build-all

This creates binaries for:

• macOS (Intel & Apple Silicon)
• Linux (AMD64 & ARM64)
• Windows (AMD64)

Troubleshooting

"converter directory not found"

The binary looks for a converter/ folder by default. Create it:

mkdir converter

Or specify a custom path:

./build/imgconverter /path/to/images

"No supported images found"

Ensure your images have supported extensions:

• .jpg or .jpeg
• .png

Permission Denied

Make the binary executable:

chmod +x build/imgconverter

Notes

1. This project was entirely created using AI, but the application has been thoroughly tested (only on macOS Sequoia).
2. This project was built primarily for my personal use, so I will not be merging pull requests or adding new features unless I need them myself. If you want to make changes or add features, feel free to fork this repository. It’s open-sourced so others can learn from it, use it as a base for their own projects, or even run the application as-is.