libjxl-Xcode

JPEG-XL is a modern image format that can compress photos to much smaller file sizes than standard JPEGs while keeping the same visual quality, or deliver noticeably better quality at the same file size. libjxl-xcode is a project that brings this image format to Apple platforms, making it easy for iOS and Mac app developers to add JPEG-XL support to their applications.

The underlying JPEG-XL software is originally written in a way that can be difficult to integrate directly into Xcode, Apple's app-building tool. This project wraps that core software in a friendly package that fits naturally into the standard Apple development workflow. It supports three popular methods that developers use to add external code to their projects: CocoaPods, Carthage, and Swift Package Manager. Once installed, developers can write code in either Swift or Objective-C to encode and decode JPEG-XL images just as they normally would.

This is primarily for mobile and desktop app developers building apps for Apple's ecosystem, including iOS, macOS, tvOS, watchOS, and visionOS. For example, a photo-sharing startup wanting to cut bandwidth costs and make images load faster might choose JPEG-XL. A developer at that company would use this project to quickly plug the format into their existing iPhone app without having to manually configure complex build settings. It connects the open-source image format to the standard Apple tools developers already use.

The project is essentially a bridge rather than a standalone app. It does not invent new image technology; it simply makes an existing tool accessible to a new audience. One notable trade-off mentioned in the project notes is that it currently has trouble running on the Apple Watch simulator during development due to a technical limitation, though it works fine on actual watch hardware.