One of the results you might see when you run a Chrome dev tools lighthouse audit on your site is that you need to use a modern image format on your site such as WebP, JPEG XR or JPEG2000. What are these formats? What’s the current state of browser support for them? Let’s dive in and take a look.
JPEG 2000
JPEG 2000 was originally proposed by the Joint Photographic Experts Group as an improvement to the JPG format. It was created in the year 2000.
For web applications, it supports transparency and compresses better than JPG compression algorithm. One of the reasons that it was not widely adopted at the time is that it is comparatively computationally intensive to encode and decode images, which slowed the standard’s adoption.
Should you being using JPEG 2000? Modern support on the web for JPEG 2000 is slim: It’s supported by Safari browsers and Chrome iOS (as it’s built on top of Safari). As I mentioned with JPEG XR, it can pay off to use it if you have the time and/or tooling to generate all the modern formats for the different browsers that you need. If you’re tight on time, just using a properly compressed progressive JPEG (85% compression is the recommend amount).
For more info about JPEG 2000, check out these sources:
https://en.wikipedia.org/wiki/JPEG_2000
https://petapixel.com/2015/09/12/jpeg-2000-the-better-alternative-to-jpeg-that-never-made-it-big/
High Performance Images by Colin Bendell, Tim Kadlec, Yoav Weiss, Guy Podjarny, Nick Doyle & Mike McCall from O’Reilly Press