#icns #icons #apple #image #image-format #file-format #parser


A library for reading and writing Apple Icon Image (.icns) files

2 releases

0.1.2 Jul 16, 2023
0.1.1 Jul 16, 2023
0.1.0 Jul 6, 2023

#2067 in Parser implementations


561 lines


The ICNS format is a file format used by Apple to store icons for macOS applications. This crate provides a simple API for reading and (and soon)writing ICNS files.


  • Write ICNS files
  • Read ICNS files


Here's a simple example of how to read an ICNS file:

You can find this example in examples/encode.rs or run it with:

cargo run --example encode
use std::fs::File;
use std::io::prelude::*;
use image::open;
use icns_rs::{IcnsEncoder, IconFormats};

fn main() -> std::io::Result<()> {
    // Open the image
    let image = match open("example.png") {
        Ok(image) => image,
        Err(e) => {
            println!("Error opening file: {}", e);
            return Ok(());

    // Create the encoder
    let mut encoder = IcnsEncoder::new();


    // Encode the image
    let data = match encoder.build() {
        Ok(data) => data,
        Err(e) => {
            println!("Error encoding image: {}", e);
            return Ok(());

    // Write data to file
    let mut file = File::create("example.icns")?;



This project is licensed under the GPLv3 license. See the LICENSE file for more details.


Contributions are welcome! Feel free to open an issue or submit a pull request.


This project is heavily inspired by:

When I started building this, I didn't know there already was a ICNS lib for rust, but, after looking at it, it was not up to my standards because of the lack of ARGB, RGB, and, Mask support. I wanted to create a modern package that was easy to use and had a simple API. I also wanted to make sure that it was well documented and had a good test suite. I hope you enjoy using this package as much as I enjoyed making it!.


~60K SLoC