Re-encoding from JPEG to AVIF will always drop quality. Lossless re-encoding from JPEG to JPEG XL makes a pixel perfect reproduction, while shrinking file size.
jxl can also extract the original jpeg bit-for-bit, meaning you can save space on disk and still serve exactly the same images as some clients expect. no rewrites.
But if you’re going through the trouble of re-encoding you might as well re-encode to AVIF, no?
Re-encoding from JPEG to AVIF will always drop quality. Lossless re-encoding from JPEG to JPEG XL makes a pixel perfect reproduction, while shrinking file size.
jxl can also extract the original jpeg bit-for-bit, meaning you can save space on disk and still serve exactly the same images as some clients expect. no rewrites.