> > The speed obtainable by lossless JXL is significantly better than what the > email above suggests - first of all, jxl_cli's --speedtest option will run > two decodes by default.
I have verified it and this does seem to be the case. So make it a *15x* slowdown vs lossless WebP. That is still astronomical, and my point still stands. I've re-measured on my laptop with 'taskset -c 0 target/release/jxl_cli --num-threads 1 --num-reps 1 --warmup-reps 0 --speedtest' and I'm seeing a 20x slowdown in practice. Not sure why it's higher than the theory - the lack of AVX-512 on this machine is to blame. Moreover, the encoder can be configured to prioritize decoding speed over > maximum compression -- for example, setting --faster_decoding 1 does not > change the compressed size significantly, but doubles decoding speed. Then perhaps only fast-decoding lossless mode should be supported in web browsers. A 7.5x slowdown instead of 15x might be excusable, depending on the use case. Also, note that the linked image is almost 100 megapixels and strongly > benefits from multi-threaded decoding. Multi-threading helps with latency on some systems but does not meaningfully affect power usage. And given that a webpage contains not only images and the CPU is already busy processing the rest of it, multi-threading is less of a boon to latency in a web browser than in an image viewer. I do not mean to derail this thread into a discussion of the details of the lossless mode and what can be done about it. Rather, I believe the lossless compression mode of JPEG XL has not received enough attention on its cost-benefit analysis (unlike the lossy mode <https://cloudinary.com/blog/jpeg-xl-and-the-pareto-front>), and should not be included in a stable release in web browsers until compelling evidence for its use cases and trade-offs is provided. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CABaUXi4%2BVHb3VWNrQC0CyCpKWd13FOz2ak%2BaJRPrgTVhW1%2BhyQ%40mail.gmail.com.
