Let's be fair, WebP lossless is pretty good, it has a couple advantages:
1. Almost always produces smaller files than PNG, even after PNG optimizers
2. Supported by all web browsers.
WebP lossless' disadvantage comes in that the maximum dimensions of the file are limited to 16383×16383. I find images larger than that on a frequent basis, it's not a very high limit. It also only supports 8-bit per color images. Good enough for screenshots, not good enough for some editors.
Lossless is a category of codecs where file size is almost the only factor anyone cares about. Pretty much all of them are fast enough to not bother measuring with encode or decode speeds.
JPEG XL will perform even better in lossless mode than WebP lossless does, but it's not currently supported by any browser (it's in Safari beta and behind a config flag in Firefox Nightly).
>but it's not currently supported by any browser (it's in Safari beta and behind a config flag in Firefox Nightly)
Your comment is 100% accurate, but it's notable that JPEG XL is coming this fall across the release versions of macOS, iOS, iPadOS, and then standalone Safari (itself being compatible back to macOS 12). Not just in Safari, but in the core media content subsystem of the core OS as well, meaning it can be immediately supported by third party apps as well effortlessly.
Given the extremely rapid uptake of Apple OS updates, by year end it will have a substantial compatible base.
Of course webp has a massive compatible base right now yet sees almost no adoption. Hopefully the quality and functional benefits of JPEG XL finally get us over that hump.
You could see another comment I made on this story. :) WebP lossy has poor enough visual quality and poor enough file size gains over JPEG (especially after MozJPEG has really squeezed the most they could out of the 1993 format), that it's wholly unappealing to anyone that would possibly care about lossy formats. Google never really advertised that WebP lossless is a thing, so in the minds of many, WebP is a failed JPEG replacement and PNG stands unopposed (even though that's untrue for a subset of images PNG supports).
1. Almost always produces smaller files than PNG, even after PNG optimizers
2. Supported by all web browsers.
WebP lossless' disadvantage comes in that the maximum dimensions of the file are limited to 16383×16383. I find images larger than that on a frequent basis, it's not a very high limit. It also only supports 8-bit per color images. Good enough for screenshots, not good enough for some editors.
Lossless is a category of codecs where file size is almost the only factor anyone cares about. Pretty much all of them are fast enough to not bother measuring with encode or decode speeds.
JPEG XL will perform even better in lossless mode than WebP lossless does, but it's not currently supported by any browser (it's in Safari beta and behind a config flag in Firefox Nightly).