Shipping JPEG XL in Chrome

Chrome has introduced support for decoding JPEG XL images with the release of version 155. JPEG XL is a next-generation image format that offers improved compression (30-50% better than JPEG), lossless compression, built-in HDR support, and lossless JPEG transcoding. It is recommended to try both AVIF and JPEG XL for optimal results, particularly for high-fidelity or lossless compression, especially for photographic images or when fine-grained progressive decoding is desired.

The primary motivation for integrating JPEG XL into Chrome was to enhance web developer experience, as suggested by consistent feedback from web developers, especially during the Interop Process discussions. The JPEG XL implementation was developed using Rust to ensure memory safety, as image decoders are critical components in web browsers, susceptible to vulnerabilities in memory-unsafe languages like C++.

To address performance concerns, the developers leveraged SIMD hardware available on modern devices by utilizing a SIMD abstraction layer. This approach allowed the creation of a multi-platform library that maintains SIMD performance optimizations without compromising on memory safety. The performance of the Rust reimplementation was evaluated across various hardware platforms using state-of-the-art techniques, including fuzzing and AI review of the code.

No memory safety bugs were discovered throughout the implementation history, further validating the advantages of using Rust.

The Chrome team actively considers feedback from developers through various channels such as bugs, surveys, and the Developer Signals Project. The integration of JPEG XL in Chrome was based on the popularity and requests from web developers. The developers encourage the use of .jxl images and animations in web pipelines, urging developers, content creators, and platform owners to provide feedback and contribute to building a faster and safer web.