Caesium Command Line Tools

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caesiumclt is a command line tool for image compression written in Rust, supporting lossy, lossless, and maximum size compression. Based on libcaesium.

Table of Contents

• Features
• Getting Started
  • Binaries
  • Installation from Source
• Usage
  • Examples
• Development
  • Requirements
  • Build

Features

• Quality-based lossy compression
• Lossless compression - the very same image is returned
• Maximum size compression - the image is compressed to a specific size
• Resize images
• Convert to different formats
• EXIF metadata preservation
• Recursive directory compression
• Folder structure preservation
• File timestamp preservation
• Custom suffix for output files
• Fast and customizable multithreaded processing

Supported formats

Format	Lossy	Lossless
JPEG	✅	✅
PNG	✅	✅
WebP	✅	✅
TIFF	❌	✅

Getting started

Binaries

You can download the latest binaries from the releases page. Supported platforms are:

• Windows (x86_64)
• macOS (x86_64/aarch64)
• Linux (x86_64/aarch64)

Installation from source

If you have Rust installed, you can install the tool using Cargo:

cargo install --git https://github.com/Lymphatus/caesium-clt caesiumclt

If you instead want to build the tool refer to the Development section.

Usage

For a full list of all flags and options refer to the full docs.

Examples

Losslessly compress image1.jpg, located in the home directory, into a folder called output

$ caesiumclt --lossless -o ~/output/ ~/image.jpg

Compress image1.jpg, located in the home directory, into a folder called output with lossy compression and quality set to 80

$ caesiumclt -q 80 -o ~/output/ ~/image.jpg

Losslessly compress image1.jpg, located in the home directory, into a folder called output and keeps EXIF metadata and original file date information

$ caesiumclt --lossless -e --keep-dates -o ~/output/ ~/image.jpg

Losslessly compress Pictures folder and subfolders, located in the home directory, into a folder called output

$ caesiumclt --lossless -R -o ~/output/ ~/Pictures

Losslessly compress Pictures folder and subfolders, located in the home directory, into a folder called output retaining the input folder structure

$ caesiumclt --lossless -RS -o ~/output/ ~/Pictures

Development

Requirements

• Rust >= 1.79.0

Build

cargo build