lazywebp - image converter

CLI tool and native macOS app to batch convert images to Webp. Handles single files, multiple files, and entire directories with concurrent processing, atomic writes, and mtime-based skip logic.

Quick Start

npx lazywebp photo.png

Converts photo.png to photo.webp in the same directory.

Install

Global (adds lazywebp to your PATH):

npm install -g lazywebp

Run without installing (via npx):

npx lazywebp photo.png

From source:

git clone https://github.com/keiver/lazywebp.git
cd lazywebp
npm install && npm run build && npm link

Usage

# Convert a single file (output next to source)
lazywebp photo.png

# Convert multiple files at once
lazywebp photo.png banner.jpg logo.gif

# Convert all images in a directory
lazywebp images/

# Convert to a separate output directory
lazywebp -o output/ images/

# Custom quality (1-100, default: 90)
lazywebp -q 80 photo.png

# Recursive subdirectory processing
lazywebp -r images/

# Combine flags
lazywebp -q 75 -r -o dist/ src/assets/

Options

| Flag | Description | |---|---| | -q, --quality <n> | WebP quality 1-100 (default: 90) | | -o, --output <dir> | Output directory (default: next to source) | | -r, --recursive | Process subdirectories recursively | | -h, --help | Show help message | | -v, --version | Show version number |

Features

• Accepts multiple input files and directories in a single command
• Skips files that haven't changed (compares mtime)
• Gracefully skips non-image files with a warning
• Atomic writes via temp file + rename
• Concurrent processing (up to 4 workers)
• Color space conversion (display-p3 / RGB to sRGB)
• Auto-rotation based on EXIF data
• Recursive subdirectory support with mirrored output structure

Supported Formats

JPG, JPEG, PNG, GIF, BMP, TIFF, WebP

macOS App — Lazy Webp

Native SwiftUI app that wraps the CLI. Drag and drop images or folders to convert them — output is generated next to each source file.

Requirements

• macOS 14+
• Swift 6.2+
• The lazywebp CLI must be installed and available in your PATH

Run in development

cd app
swift run

Install to /Applications

cd app
./install-app.sh

This builds a release binary, creates an app bundle at /Applications/Lazy Webp.app (dev.keiver.lazywebp), and signs it locally.

App Features

• Drag-and-drop files and folders
• File picker dialog
• Quality slider (1-100)
• Per-file size and savings display
• Live progress tracking with cancel support
• Always-on-top floating window
• Menu bar icon with quick access
• Launch at login option
• Install to /Applications from the menu bar

Requirements

| Component | Requires | |---|---| | CLI | Node.js 18+, Sharp | | macOS App | macOS 14+, Swift 6.2+ |

npm Scripts

| Script | Description | |---|---| | npm run dev | Run directly from TypeScript source | | npm run build | Compile to JavaScript in dist/ | | npm start | Run compiled build | | npm test | Run tests | | npm run test:watch | Run tests in watch mode |

License

MIT