Apple reportedly added support for JPEG XL to the iPhone Camera app in iOS 18. That’s left many iPhone users wondering, what the heck is JPEG XL?
It’s intended to be the replacement for the classic JPEG image format with new features for use on the web. And apparently, iPhone users soon can take pictures in this format, not simply view them.
JPEG XL for iPhone photos going on the web
The original JPEG version launched way back in 1992. It’s a lossy format, which means it can reduce the size of image files by lowering the quality of the photo. It’s been a huge success, with billions of JPEG images taken every day.
The Joint Photographic Experts Group, a standards body that made the original, set out to create an improved version. Its description of the format says, “JPEG XL is designed to meet the needs of image delivery on the web and professional photography.”
JPEG XL is more flexible than its predecessor, offering both lossy and lossless options. It can reduce image files sizes by 20:1 or even 50:1. The format supports wide color gamut plus high dynamic range and high bit-depth images.
But the creators took backward compatibility into account. Existing JPEG files can be losslessly remade into JPEG XL and later restored to the exact same JPEG file.
Still, the new version offers capabilities far beyond the original. “JPEG XL further includes features such as animation, alpha channels, layers, thumbnails, lossless and progressive coding to support a wide range of use cases,” promises the trade group that developed it.
The developers thought about photo galleries, e-commerce, social media, user interfaces and cloud storage when designing JPEG XL. It can handle images up to 1 terapixel, and files use the .jxl extension.
The format is royalty-free, so no company can demand payments from software developers for building support for it into their applications.
Coming to the Camera app
While a recent unconfirmed report says JPEG XL support will appear in iPhone 16, it’s vey likely previous iPhone models will also get it with iOS 18.
And to be clear, there’s nothing in this report to indicate Apple intends to prefer the new format. The Camera app already supports HEIF, HEIF Max, ProRaw, ProRaw MAX and JPEG. It seems likely Apple simply will add another format to the list.
Or it could replace JPEG, as that’s the intent of the image format’s developers. If so, going to Settings -> Camera -> Formats in iOS 18 and choosing Most Compatible will cause photographs to be taken in JPEG XL.
However, there’s a wrinkle: at this point few web browsers support JXL images. Safari does, but others are still working toward implementing the image format. Still, Apple throwing it’s hefty weight behind the format will surely kickstart adoption.
