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shevy-java • today at 12:29 PM • 1 reply • view on HN

About three years ago I had to find a replacement for old .jpg files and .png files.

The main two contenders were .avif and .webp. For a few reasons, I selected .avif and in hindsight I think it was the better, choice. Both would be objectively better than jpg or png.

With JPEG XL ... hmmm. AVIF is not perfect, in particular when the compression rate is very high I noticed that some photos lose a lot of intrinsic quality that is not instantly obvious; I noticed this when I took various pictures over the years from outdoors. Still, AVIF beats jpg and png just about on every metric when compression is required. With JPEG XL I guess I have to re-evaluate, but right now I am still sticking to avif. The two factors that will be important for me is compression ratio and quality. I am ok with a bit of loss of quality, if the compression is better, but I am not sure JPEG XL beats AVIF here clearly either, so I am not sure what to do with JPEG XL.


Replies

F3nd0 • today at 2:20 PM

Both JPEG XL and WebP far exceed AVIF when it comes to lossless. For lossy, AVIF used to do better at low quality and JPEG XL at high quality. But apparently AV1 encoders have improved a lot since then, closing the distance. An article comparing the two was posted recently:

https://news.ycombinator.com/item?id=49690554

The author, who has worked on said AV1 encoders, has expressed doubt that JPEG XL encoders could improve much with only reasonable amounts of effort, but that was also only their personal (if educated) guess. With JPEG XL finally seeing adoption on the web, we will hopefully see work on the reference encoder resume in earnest soon.

So for now, I’d say you’re fine with AVIF. Unless you’re doing lossless, because AVIF sucks at lossless. (And JPEG XL has the unique feature of supporting lossless JPEG transcoding, too.)