I barely slept last night: Why is 10-bit 4:2:0 AVIF sometimes able to compete with JXL in visually lossless quality? Logically this should be IMPOSSIBLE because 75% of color information doesn't exist.>90 = visually lossless.>Distortion not noticeable by an average observer in a flicker test at 1:1 from a normal viewing distance.>This corresponds to the typical output of cjxl -d 0.5 / -q 95 or libjpeg-turbo 4:4:4 quality 95.That last part is very important.https://github.com/cloudinary/ssimulacra2cjxl in.png out.jxl -q 95Q_95 JXL SSIMU2= 90.16234362495 KBhttps://files.catbox.moe/5vvoqz.jxlavifenc --sharpyuv -d 10 -y 420 --cicp 1/13/1 -a tune=iq -q 85 in.png out.avifQ_85 AVIF SSIMU2= 90.63495388469 KBhttps://files.catbox.moe/drgb7g.avif
If anyone is wondering why I'm even testing 4:2:0 AVIF when 4:4:4 AVIF exists, it's because it's an inherent limitation of AVIF HW decoding that is now showing up on Android 15 devices. If you have one this AVIF should decode on your stock google files browser without having to download a third party image viewer.
Here is the libjpeg-turbo 4:4:4 quality 95 JPG.JPG 4:4:4 SSIMU2= 89.82046347799 KB
Another bizarre example of this happening. Neither of these images is Anime and that's the only image source I expected to achieve high quality in 10-bit AVIF 4:2:0 desu.cjxl in.png out.jxl -q 96Q_96 JXL SSIMU2= 90.12365188973 KBhttps://files.catbox.moe/almuaz.jxlavifenc --sharpyuv -d 10 -y 420 --cicp 1/13/1 -a tune=iq -q 84 in.png out.avifQ_84 AVIF SSIMU2= 90.55000812950 KBhttps://files.catbox.moe/4uw9e1.avif
JPG 4:4:4 SSIMU2= 90.076725051654 KB
nobody cares
