Comment by linolevan
1 day ago
I think people are really forgetting that JXL's encoders are bad right now. For instance, in TFA Jake presents
- The Firefox screenshot w/ lossless JXL at 66.9kB, when with a better encoder you get get it down to like 40.7kB (39% smaller) [1] (or 43kB if you need it to work with jxl-rs [2])
- The cat illustration w/ lossless JXL at 255.3kB, when with a better encoder you can get it down to 178kB (30% smaller) [3]
[1] https://www.linolevan.com/05-screenshot.jxl
Oh, that explains! I tried AVIF and JXL a few years ago and one of the two took ages to encode (a minute versus <1s for jpeg) to get similar compression ratios, and the other was somewhat reasonable on cpu complexity but significantly worse quality at the same size / much bigger to achieve the same quality as good old jpeg. I ended up concluding that jpeg is still the best for the specific image I was trying to lossily compress, but that was probably just the encoder then
Happy to see your version of the cat illustration doesn't come with massive decoder overhead. Are you planning to open source this encoder?
It's just a side project I'm working on with some friends. May release it if it's interesting to folks.
I would love to try it out.
1 reply →
> with a better encoder you can get it down to 178kB
What encoder?
Encoder I’m working on as a side project, not publicly released (but feel free to pull the included files to prove it to yourself)
Yeah, it's very cool that jixel was able to achieve such large efficiency improvements!
This is not jixel though. It was their own encoder
Thank You. I was about to post I suspect both of those images would have worked better with JXL lossless.
Curious what is the better encoder here referring to?
It's an unreleased one. There's a whole section in the article about lossless, which includes data on those images, but not this mystery unreleased encoder https://jakearchibald.com/2026/jpeg-xl-vs-avif/#lossless