Readit Newscomputerbuster commented on Oavif: Faster target quality image compression giannirosato.com/blog/pos... · Posted by u/computerbuster
Good. These files in a format that I can't easily manipulate with existing tools are a major hassle. Stay with GIF, JPEG, and PNG.
Existing tools really just need to do a better job keeping up.
computerbuster commented on Oavif: Faster target quality image compression giannirosato.com/blog/pos... · Posted by u/computerbuster
Thanks for posting this, really interesting!
I've been building a wordpress plugin that converts JPEG to AVIF on the local server (since everyone wants to sell a service to convert in the cloud).
As a photographer who wants high quality photos on their portfolio website I love how AVIF respects color more the webp.
Very cool use case! 4:4:4 support + 10-bit color make AVIF very compelling here.
computerbuster commented on Oavif: Faster target quality image compression giannirosato.com/blog/pos... · Posted by u/computerbuster
I mean to be fair writing is on the wall some when a superior format like jpegxl exists but is arbitrarily held back purely because Google's Chromium team wants to push the format they made over the format another Google team worked on.
Superior in file size, image quality, computation required for equivalent quality encoding, no arbitrary resolution caps, progressive decoding which also lets you create 'thumbnails' or resizes by just cutting the byte stream, while also having features to help legacy jpeg files benefit from newer compression losslessly. The only benchmark avif bests at is abhorrently low quality levels that no one genuinely uses.
I'm a big fan of JPEG XL, but even its most dedicated fans have given up the argument that it is the best for compression efficiency. AVIF's generational leap took place in August 2024 with Tune Still Picture in SVT-AV1-PSY, so much so that Google integrated it into their own encoder and has done very impressive work optimizing it further for the human visual system. JPEG XL's strongest quality is its featureset; lossless JPEG recompression, for example, is really incredible
computerbuster commented on Fast SSIMULACRA2 Implementation in Zig github.com/gianni-rosato/... · Posted by u/computerbuster
It does not match with the reference implementation in my side:
#!/bin/sh
# originally from https://jpegxl.info/images/precision-machinery-shapes-golden-substance-with-robotic-exactitude.jpg
# URL1="http://intercity-vpn.de/files/2025-10-04/upload/precision-machinery-shapes-golden-substance-with-robotic-exactitude.png"
# URL2="http://intercity-vpn.de/files/2025-10-04/upload/image-png-all-pngquant-q13.png"
curl "$URL1" -so test.png
curl "$URL2" -so distorted.png
# https://github.com/cloudinary/ssimulacra2/tree/main
ssimulacra2 test.png distorted.png
5.90462597
# https://github.com/gianni-rosato/fssimu2
fssimu2 test.png distorted.png
2.17616860Hi, author here – the README covers this in the Performance section: https://github.com/gianni-rosato/fssimu2?tab=readme-ov-file#...
If you run the `validate.py` script available in the repo, you should see correlation numbers similar to what I've pre-tested & made available in the README: fssimu2 achieves 99.97% linear correlation with the reference implementation's scores.
fssimu2 is still missing some functionality (like ICC profile reading) but the goal was to produce a production-oriented implementation that is just as useful while being much faster (example: lower memory footprint and speed improvements make fssimu2 a lot more useful in a target quality loop). For research-oriented use cases where the exact SSIMULACRA2 score is desirable, the reference implementation is a better choice. It is worth evaluating whether or not this is your use case; an implementation that is 99.97% accurate is likely just as useful to you if you are doing quality benchmarks, target quality, or something else where SSIMULACRA2's correlation to subjective human ratings is more important than the exactness of the implementation to the reference.
computerbuster commented on The Multimedia Renaissance giannirosato.com/blog/pos... · Posted by u/computerbuster
The past two years have seen significant advancements in video and image compression, particularly with the maturation of the SVT-AV1 video encoder and improvements to AVIF image compression. These developments, coupled with faster and more accessible developer tools, have made it easier to produce high-quality compressed media. I have a lot of optimism for the future with AV2 and the potential for further community-driven innovation in open-source compression technology.
> The error will be much smaller than the error between ssimu2 and actual subjective quality, so I wouldn't worry about it.