Hello, everyone! I could not reply for another 24 hours because I am a new user, and I just wanted to apologize and say that I did not mean to start a controversy.
The JPEG XL that someone mentioned sounds good from its website, almost too good to be true! I appreciate that update!
I have tried out both AVIF and JPEG XL on a test photo at their default settings.
Unfortunately, only JPEG and PNG files appear to be able to be uploading here, so I can’t post the results.
I’ll try to put a link to them (if allowed) and summarize:
All at the default settings, no changes made, just a simple convert command using “magick” from brew.sh on my Mac.
JPEG XL compressed size 2.0 MB, quality appears excellent
s@ecuredownload.us/day/JAM02024P01.jxl
AVIF compressed size 437 KB, quality appears excellent (honestly cannot tell a difference)
s@ecuredownload.us/day/JAM02024P01.avif
Original photo in PNG lossless format at 18.7 MB:
s@ecuredownload.us/day/JAM02024P01.png
Visual quality of both JPEG XL and AVIF seems to be visually the same as the PNG at their default settings.
File size of JPEG XL seems to be over four times larger/worse than AVIF at their default settings.
I did investigate if it was possible to change the JPEG XL settings from the default to get the file size down to match the AVIF, and I had to lower the quality parameter all the way down to 25% to get a 436 KB JPEG XL file (as close as possible to the 437 KB AVIF file).
The link to the 25% 436 KB JPEG XL file is here:
s@ecuredownload.us/day/JAM02024P01-q25.jxl
However, in this JPEG XL file that matches the size of the AVIF file, the quality is no longer excellent, but much lower.
My initial conclusion is that JPEG XL is developing but not yet ready or even close to matching the efficiency or the quality of AVIF, at least not at the same file size.
I hope this helps, with a real-world photo comparison.
Please don’t share the photo anywhere outside this forum. You do not have my permission.
Update: I noticed that the forum automatically loaded the AVIF file even though I used a plain text URL, but that the forum doesn’t support auto loading JPEG XL content yet from a plain text URL.
Update 2: removed images from public view as per recommendation of user stuck. You can still see them if you wish by removing the @ sign between the first two letters of the URL. If you don’t have time for this, the result was that AVIF at default settings vs. JPEG XL at default settings was same visual quality, but AVIF output was 4x smaller size than the JPEG XL output. So the advantage there goes to AVIF. When I left AVIF on default settings but changed the settings to get the file size down to the same size with JPEG XL, the quality of JPEG XL had to be lowered all the way to 25% and looked about 10 times worse visually.
So in summary:
Visual advantage at same file size is 10x in favor of AVIF.
File size advantage at same visual quality is 4x in favor of AVIF.
Winner is AVIF. Which is confusing because the JPEG XL website claims that it is the best of all image formats.
I would appreciate if someone else could help confirm with their own images.