One of the cooler and lesser known features of JPEG XL is a mode to losslessly transcode from JPEG while achieving ~20% space reduction. It’s reversible too because the original entropy coded bitstream is untouched.

Notably GCP is rolling this out to their DICOM store API, so you get the space savings of JXL but can transcode on the fly for applications that need to be served JPEG.

Only know this because we have tens of PBs in their DICOM store and stand to save a substantial amount of $ on an absurdly large annual bill.

Native browser support is on our wishlist and our contacts indicate the chrome team will get there eventually.