QOI - The “Quite OK Image Format” for fast, lossless image compression

Single-file MIT licensed library for C/C++

See qoi.h for the documentation and format specification.

Why?

Compared to stb_image and stb_image_write QOI offers 20x-50x faster encoding, 3x-4x faster decoding and 20% better compression. It's also stupidly simple and fits in about 300 lines of C.

Example Usage

qoiconv.c converts between png <> qoi
qoibench.c a simple wrapper to benchmark stbi, libpng and qoi

MIME Type, File Extension

The recommended MIME type for QOI images is image/qoi. While QOI is not yet officially registered with IANA, I believe QOI has found enough adoption to prevent any future image format from choosing the same name, thus making a MIME type collision highly unlikely (see #167).

The recommended file extension for QOI images is .qoi

Limitations

The QOI file format allows for huge images with up to 18 exa-pixels. A streaming en-/decoder can handle these with minimal RAM requirements, assuming there is enough storage space.

This particular implementation of QOI however is limited to images with a maximum size of 400 million pixels. It will safely refuse to en-/decode anything larger than that. This is not a streaming en-/decoder. It loads the whole image file into RAM before doing any work and is not extensively optimized for performance (but it's still very fast).

If this is a limitation for your use case, please look into any of the other implementations listed below.

Improvements, New Versions and Contributing

The QOI format has been finalized. It was a conscious decision to not have a version number in the file header. If you have a working QOI implementation today, you can rest assured that it will be compatible with all QOI files tomorrow.

There are a lot of interesting ideas for a successor of QOI, but none of these will be implemented here. That doesn't mean you shouldn't experiment with QOI, but please be aware that pull requests that change the format will not be accepted.

Likewise, pull requests for performance improvements will probably not be accepted either, as this "reference implementation" tries to be as easy to read as possible.

Tools

floooh/qoiview - native QOI viewer
pfusik/qoi-fu - QOI Plugin installer for Windows Explorer, Finder, GNOME, GIMP, Paint.NET and XnView
iOrange/QoiFileTypeNet - QOI Plugin for Paint.NET
iOrange/QOIThumbnailProvider - Add thumbnails for QOI images in Windows Explorer
Tom94/tev - another native QOI viewer (allows pixel peeping and comparison with other image formats)
qoiconverterx QOI <=> PNG converter available on the Mac App Store
kaetemi/qoi-ma - QOI Bitmap I/O Plugin for 3ds Max
rtexviewer - texture viewer, supports QOI
rtexpacker - texture packer, supports QOI
DmitriySalnikov/godot_qoi - QOI GDNative Addon for Godot Engine
dan9er/farbfeld-convert-qoi - QOI <=> farbfeld converter
LTMX/Unity.QOI - QOI Importer and Exporter for the Unity3D Game Engine
Ben1138/unity-qoi - QOI Importer(only) support for the Unity3D Game Engine
xiaozhuai/jetbrains-qo - QOI Support for Jetbrains' IDE.
serge-ivamov/QOIql - MacOS QuickLook plugin for QOI
tobozo/kde-thumbnailer-qoi - QOI Thumbnailer for KDE
walksanatora/qoi-thumbnailer-nemo - QOI Thumbnailer for Nemo
hzeller/timg - a terminal image viewer with QOI support
LuisAlfredo92/Super-QOI-converter - A program to convert JPG, JPEG, BMP, and PNG to QOI
- Console version: Available for Linux, OSX and Windows
- GUI version: Available only for windows
tacent view - Image and texture viewer, supports QOI
colemanrgb/qoi2spr - A variety of applications for decoding and encoding of QOI images on RISC OS

Implementations & Bindings of QOI

pfusik/qoi-fu - Fusion, transpiling to C, C++, C#, D, Java, JavaScript, Python, Swift and TypeScript
kodonnell/qoi - Python
JaffaKetchup/dqoi - Dart, with Flutter support
Cr4xy/lua-qoi - Lua
superzazu/SDL_QOI - C, SDL2 bindings
saharNooby/qoi-java - Java
MasterQ32/zig-qoi - Zig
rbino/qoix - Elixir
NUlliiON/QoiSharp - C#
aldanor/qoi-rust - Rust
zakarumych/rapid-qoi - Rust
takeyourhatoff/qoi - Go
DosWorld/pasqoi - Pascal
elihwyma/Swift-QOI - Swift
xfmoulet/qoi - Go
erratique.ch/qoic - OCaml
arian/go-qoi - Go
kchapelier/qoijs - JavaScript
KristofferC/QOI.jl - Julia
shadowMitia/libqoi - C++
MKCG/php-qoi - PHP
LightHouseSoftware/qoiformats - D
mhoward540/qoi-nim - Nim
wx257osn2/qoixx - C++
Tiefseetauchner/lr-paint - Processing
amstan/qoi-fpga - FPGA: verilog
musabkilic/qoi-decoder - Python
mathpn/py-qoi - Python
JohannesFriedrich/qoi4R - R
shraiwi/mini-qoi - C, streaming decoder
10maurycy10/libqoi/ - Rust
0xd34df00d/hsqoi - Haskell
418Coffee/qoi-v - V
Imagine-Programming/QoiImagePlugin - PureBasic
Fabien-Chouteau/qoi-spark - Ada/SPARK formally proven
mzgreen/qoi-kotlin - Kotlin Multiplatform
Aftersol/Simplified-QOI-Codec - C99, encoder and decoder, freestanding
AuburnSounds/gamut - D
AngusJohnson/TQoiImage - Delphi
MarkJeronimus/qoi-java-spi - Java SPI
aumouvantsillage/qoi-racket - Racket
rubikscraft/qoi-stream - C99, one byte at a time streaming encoder and decoder
rubikscraft/qoi-img - NodeJS typescript, bindings to both QOIxx and qoi-stream
grego/hare-qoi - Hare
MrNocole/ZTQOI - Objective-C
bpanthi977/qoi - Common Lisp
Floessie/pam2qoi - C++
SpeckyYT/spwn-qoi - SPWN
n00bmind/qoi - Jai
SixLabors/ImageSharp - C# image proccesing library
zertovitch/gid - Ada
nazrin/lil - Lua image library

QOI Support in Other Software

Amiga OS QOI datatype - adds support for decoding QOI images to the Amiga operating system.
SerenityOS - supports decoding QOI system wide through a custom cpp implementation in LibGfx
Raylib - supports decoding and encoding QOI textures through its rtextures module
Rebol3 - supports decoding and encoding QOI using a native codec
c-ray - supports QOI natively
SAIL - image decoding library, supports decoding and encoding QOI images
Orx - 2D game engine, supports QOI natively
IrfanView - supports decoding and encoding QOI through its Formats plugin
ImageMagick - supports decoding and encoding QOI, since 7.1.0-20
barebox - bootloader, supports decoding QOI images for splash logo, since v2022.03.0
KorGE - & KorIM Kotlin 2D game engine and imaging library, supports decoding and encoding QOI natively since 2.7.0
DOjS - DOS JavaScript Canvas implementation supports loading QOI files
XnView MP - supports decoding QOI since 1.00
ffmpeg - supports decoding and encoding QOI since 5.1
JPEGView - lightweight Windows image viewer, supports decoding and encoding of QOI natively, since 1.1.44
darktable - photography workflow application and raw developer, supports decoding since 4.4.0
KDE - supports decoding and encoding QOI images. Implemented in KImageFormats
EFL - supports decoding and encoding QOI images since 1.27.
Swingland - supports QOI decoding/loading via the ImageIO API of this Java Swing reimplemenation for Wayland
Imagine - supports decoding and encoding QOI images since 1.3.9
Uiua - supports decoding and encoding QOI images since 0.8.0

Packages

AUR - system-wide qoi.h, qoiconv and qoibench install as split packages.
Debian - packages for binaries and qoi.h
Ubuntu - packages for binaries and qoi.h

Packages for other systems tracked at Repology.

theo77186 / qoi