I've put together an updated version of the Sponza scene with uncompressed PNG and compressed AVIF textures. I wrote about the process and compared the results against KTX.
www.ludicon.com/castano/blog...
#webgpu #web3d #sparkjs
New Halide blog post on post-processing for chroma as it is relevant to compression efficiency: halide.cx/blog/chroma-...
Seems like you can get a roughly 2% efficiency improvement with 4:2:0 decoder output just with smarter post-processing for chroma. Pretty neat!
#avif #webp #jpeg
the 2nd part of my dithering visual article is finally out!
🔗 visualrambling.space/dithering-pa...
this one mainly explores the threshold map and how it generates those unique visual patterns
hope you enjoy this as much as I enjoyed making it!
made with #threejs & #animejs
SVT-AV1 4.0.0 is here!
Changelog: gitlab.com/AOMediaCodec...
SVT-AV1-PSY's porting efforts are fully complete, and this release also features huge AVIF improvements. Maybe the most exciting release to date by my standards – SVT-AV1 is finally a real perceptual encoder!
#av1 #avif #compression
Happy Holidays! Introducing fcvvdp, a faster CVVDP implementation: github.com/halidecx/fcv...
Compared to the reference implementation running on the CPU, fcvvdp is faster (~15%) despite being single-threaded. It sees stronger wins with user time (up to ~15x) and memory usage (>90% less memory).
Here’s the talk: https://youtube.com/watch?v=NtLHRX4uFhw
SVT-AV1-HDR 3.1.3 "Cyclonus" is out! Including all-new features from SVT-AV1, plus code cleanups and stability fixes.
Get the newest version of this all-purpose AV1 video encoder! ffmpeg and HandBrake builds are available by clicking the link below:
github.com/juliobbv-p/s...
Enhancing HDR on Instagram for iOS With Dolby Vision: https://engineering.fb.com/2025/11/17/ios/enhancing-hdr-on-instagram-for-ios-with-dolby-vision/ #av1 #vp9 #hdr
Oh that's awesome to hear! Considering we also get user-defined QMs in AV2 (that's the one I'm most excited for, thanks Julio) I'm expecting AV2F (or whatever it will be called, if it happens) to be very good
I spoke with @juliobbv.bsky.social at VideoLAN Dev Days in London!
Here are our slides, discussing SVT-AV1-PSY: giannirosato.com/files/svt-av...
I'll find access to the video & post it soon!
Thanks @ericportis.com – glad you’re enjoying my work :)
Introducing oavif: faster target quality image compression
giannirosato.com/blog/post/oa...
oavif can be up to 63% faster than traditional target quality encoders. Learn how in the attached blog post!
#av1 #avif #compression
fssimu2 has its first release! github.com/gianni-rosat...
fssimu2 is a fast SSIMULACRA2 implementation in Zig, with support for distortion map output. It is ~23% faster than the reference implementation at ~40% less memory usage, while being 99.97% accurate. Give it a look if you're interested!
New Halide blog post!
halide.cx/blog/consist...
Quality and speed define an image encoder's compression performance. Consistency is a close third, and easily overlooked in image encoder design. What value does it provide, and how can we measure it?
#avif #webp #jxl #jpegxl #compression
The Halide Compression website (halide.cx) now has an Atom feed – just paste the URL into your favorite RSS reader and you should be good to go!
New blog post about my experiences using spark.js with three.js:
www.ludicon.com/castano/blog...
Re-posts and feedback appreciated!
(I should clarify, this isn't a tech support question – I am interested in working with Imgix to improve your WebP compression)
Is the source code for your site available anywhere?
Hey, not sure if this is the right place to reach you about Imgix, but I have a couple of questions about WebP deployment – if you could shoot me a message here on Bluesky to continue that'd be great (up to you, I know this is kind of out of the blue)
Anyone using rss/atom readers can now type `giannirosato.com` into their reader to get my website's atom feed
I got to interview Julio Barba from Google for the Halide blog: halide.cx/blog/julio-b...
Go check it out if you're interested in what the next decade of multimedia tech might look like!
Completely redesigned my website with Zola (www.getzola.org) – check it out at giannirosato.com
Let me know if any links are broken if you link to my site – it should be fully backwards compatible with my old link hierarchy
The “AV1 is a disaster” myth
Here’s what’s actually true:
- SVT-AV1 is fast, fully multithreaded and packed with SIMD.
- It scales beautifully on modern CPUs.
- It beats x264, x265, and VP9 in bitrate vs runtime.
AV1 on CPU isn’t a disaster. It’s quietly winning.
Tune 3: Still Picture is coming to SVT-AV1: https://gitlab.com/AOMediaCodec/SVT-AV1/-/merge_requests/2489#note_2704093242
Formerly Tune 4 in SVT-AV1-PSY. Thank you @juliobbv.bsky.social !
I have the same hope … let’s see if it pans out 🤞
Yeah I think they do – JPEG XL is great, and I’m happy it’s seeing more adoption on the web! I remain worried about its status since Google removed support from Chrome, but since Apple added support systemwide I am relieved to see that driving adoption
:( hope you and the computer both get better soon
![“[sorry for the spam] Just wanted to say that theguardian.com is on `tune=iq` for the last two weeks (we serve AVIF to non-JXL-supporting browsers) and we couldn’t be more happy. Encoder consistency is much, much higher (still not as good as JXL, but that’s just an impression, not a rigorous assessment): some highly compressible images where delicate detail was being obliterated grown even ~3× in filesize and look much better while unnecessarily weighty images shrank, mostly without any perceptible degradation. Interestingly, we kept the same quality values (which differ by dpr) and as much as we can say, the overall bandwidth stayed more or less the same (I can’t see any change in the graph), so it’s likely the massive reduction of rare weighty images offset small images growing.
Huge thanks to juliobbv for his work on `tune=iq` and to whomever else worked on it. And to friends at our image CDN (Fastly). And to everyone here as without this server, I wouldn’t even know about it…
As always, we welcome improvements to any and all encoders. So the idea of “splitting Julio” couldn’t sound more exciting 😉.”](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:lj7y6n7ouwe2276ubo5cizaa/bafkreiabxrmpl67iegnifzu64fdckai6yjodzjneksoknqebyndshcjila@jpeg)
“[sorry for the spam] Just wanted to say that theguardian.com is on `tune=iq` for the last two weeks (we serve AVIF to non-JXL-supporting browsers) and we couldn’t be more happy. Encoder consistency is much, much higher (still not as good as JXL, but that’s just an impression, not a rigorous assessment): some highly compressible images where delicate detail was being obliterated grown even ~3× in filesize and look much better while unnecessarily weighty images shrank, mostly without any perceptible degradation. Interestingly, we kept the same quality values (which differ by dpr) and as much as we can say, the overall bandwidth stayed more or less the same (I can’t see any change in the graph), so it’s likely the massive reduction of rare weighty images offset small images growing. Huge thanks to juliobbv for his work on `tune=iq` and to whomever else worked on it. And to friends at our image CDN (Fastly). And to everyone here as without this server, I wouldn’t even know about it… As always, we welcome improvements to any and all encoders. So the idea of “splitting Julio” couldn’t sound more exciting 😉.”
Exciting #avif news – libaom’s tune iq (derived from SVT-AV1-PSY’s Tune 4) is used across The Guardian’s website now. They say they serve mostly AVIF, with JPEG XL shipped when supported. Very exciting stuff! Thanks @juliobbv.bsky.social!
Post: “This is one of the craziest ideas l've ever seen. He converted a drawing of a bird into a spectrogram (PNG -> Soundwave) then played it to a Starling who sung it back reproducing the PNG.” Response: “Ok fine. Sure. Whatever. We can save PNGs to birds. I give up. You win world”
New post! After my previous post about image compression, a few people asked me to try different encoder settings. So I went ahead and tested a couple of them :)
www.rachelplusplus.me.uk/blog/2025/07...
