4 ms·
Your benchmark seems to lack options used. JPEG XL has two main knobs for quality and speed, as I've previously mentioned in [1], and the default effort 7 (whic
by lifthrasiir 4y ago
Your benchmark seems to lack options used. JPEG XL has two main knobs for quality and speed, as I've previously mentioned in [1], and the default effort 7 (which is, assuming that you didn't set any other options, presumably used in your benchmark) would definitely prefer compression ratio over compression speed. You will need multiple entries for JPEG XL with varying efforts for a fair compraison.
[1] https://news.ycombinator.com/item?id=33401540 https://news.ycombinator.com/item?id=33401540
- nigeltao 4y agoIIUC, the quality knob (not the effort knob) isn't relevant for lossless encoding. Knobs are also less relevant for lossless decoding, where there's only one correct output for any given input. In any case, my code (https://github.com/nigeltao/qoir/blob/main/adapter/jxl_adapter.cpp https://github.com/nigeltao/qoir/blob/main/adapter/jxl_adapt...) copy/pastes examples/encode_oneshot.cc from the libjxl repository, plus an additional JxlEncoderSetFrameLossless call. So I'm using whatever knob values that the libjxl example uses, i.e. the default knob values. If there are better knob values for lossless, let me know.
- pizza 4y agoJust want to mention that modular mode (the encoding technique for lossless mode) does have flags that let you have a bit of loss (by changing a quality flag), though by default what you said is correct, it is fully lossless.