Encoding speed is not really a concern for web uses, where the image is decoded potentially millions or even billions of times more than it is encoded.
I agree, PSNR is a terrible measure of quality. The study "Benchmarking JPEG XL lossy/lossless image compression" (https://research.google/pubs/benchmrking-jpeg-xl-lossylossle...) which you are an author on included a controlled subjective evaluation done by EPFL using an ITU recommend methodology. The subjective results concluded:
"HEVC with SCC generally results in better rate/distortion performance when compared to JPEG XL at low bitrates (< 0.75), better preserving sharp lines and
smooth areas"
It is known that AVIF performs better than HEVC. Can you say why it was not included in your 2020 subjective evaluation? It would be nice to not need to speculate on the relative quality of AVIF v JPEG XL at web bitrates.
I agree, PSNR is a terrible measure of quality. The study "Benchmarking JPEG XL lossy/lossless image compression" (https://research.google/pubs/benchmrking-jpeg-xl-lossylossle...) which you are an author on included a controlled subjective evaluation done by EPFL using an ITU recommend methodology. The subjective results concluded:
"HEVC with SCC generally results in better rate/distortion performance when compared to JPEG XL at low bitrates (< 0.75), better preserving sharp lines and smooth areas"
It is known that AVIF performs better than HEVC. Can you say why it was not included in your 2020 subjective evaluation? It would be nice to not need to speculate on the relative quality of AVIF v JPEG XL at web bitrates.