In Operation
qoiconv lets us convert existing PNG files to the QOI format, as well as convert them back. The syntax is simple.
From testing a range of image files, we saw image compression times over 30 times faster than the Libpng library. The compression QOI provides is, on average, about the same as that of PNG, but it does depend on the image data. We did see files significantly larger with QOI.
There are only a few native image viewers that support the .qoi file. On the first page of this articles we installed qoiview and tev.
Here’s a high resolution image displayed with qoiview.
For a more featureful image viewer that supports QOI, check out tev.
Summary
QOI is pretty feature-complete. It’s not designed to be a complex format, but it combines several simple ideas. QOI can also be compressed with general compression algorithms.
With time, hopefully more software will support the QOI format. But it’s already useful for compressing and archiving images.
qoiconv is written in C, but there are implementations available for other languages including Go, Rust, Python, Java, Dart, and Lua.
For more command-line image compression tools, explore our roundup. All free and open source goodness.
Website: qoiformat.org
Support: GitHub Code Repository
Developer: Dominic Szablewski
License: MIT License
QOI is written in C. Learn C with our recommended free books and free tutorials.
Pages in this article:
Page 1 – Introduction and Installation
Page 2 – In Operation and Summary
Related Software
| Console Based Image Compression Tools | |
|---|---|
| MozJPEG | Mozilla JPEG Encoder Project |
| pngquant | Utility and a library for lossy compression of PNG images |
| SVGO | Node.js library and command-line application for optimizing SVG files |
| Oxipng | Multithreaded PNG optimizer, forked from Optipng |
| libjxl | Reference implementation of JPEG XL |
| libjpeg-turbo | JPEG image codec |
| QOI | The Quite OK Image Format |
| YOGA | Yummy Optimizer for Gorgeous Assets |
| pngcrush | Optimizer for PNG files |
| jpegoptim | Optimize JPEG files. Lossless and lossy compression available |
| OptiPNG | Advanced PNG optimizer |
| Guetzli | Perceptual JPEG encoder with excellent compression density at high quality |
| ECT | Fast and effective C++ file optimizer |
| Crunch | Lossy PNG image file optimization |
| zopflipng | PNG optimisation tool using zopfli |
| JPEG Archive | Utilities for archive JPEGs for long term storage |
| optimizt | CLI image optimization tool |
| picopt | Multi format lossless image optimize |
| tinifier | CLI tool for compressing images using the TinyPNG API |
Read our verdict in the software roundup.
 Explore our comprehensive directory of recommended free and open source software. Our carefully curated collection spans every major software category.This directory is part of our ongoing series of informative articles for Linux enthusiasts. It features hundreds of detailed reviews, along with open source alternatives to proprietary solutions from major corporations such as Google, Microsoft, Apple, Adobe, IBM, Cisco, Oracle, and Autodesk. You’ll also find interesting projects to try, hardware coverage, free programming books and tutorials, and much more. Discovered a useful open source Linux program that we haven’t covered yet? Let us know by completing this form. |