juliobbv

4 ms·

1.
by juliobbv 11d ago
By "small", it's meant in a relative sense. JXL's coded blocks can be as big as 64x64, and block boundaries can create visible seams. Example: https://juliobbv.com/pics/photo.jxl These seams are esp
2.
by juliobbv 11d ago
> Sure, that was kind of my point, but I think it's important to point out it's the default. I had read somewhere else in the comments that they just "happened" to use 2 passes (that I now realized was also written by
3.
by juliobbv 11d ago
Yes, he'll fix the speedtest flag thing (which BTW, several people were accidentally using it wrong because the feature is unergonomic AF, but it's convenient to blame the user for "holding it wrong" right?). No, single-
4.
by juliobbv 11d ago
Ah, no worries! I can't speak for Iris and Aperture, but both "tune IQ" modes in SVT-AV1 and libaom had extensive human evaluations to make sure they weren't accidentally being benchmaxxed at the expense of subjective qu
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by juliobbv 11d ago
> I find it misleading to call AVIF's "up to four passes" "very flexible". Wow, what a way to misquote me. Let me repeat what I actually said: > Progressive AVIF is very flexible: it supports up to four passes
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by juliobbv 12d ago
Let's be productive: https://pengbins.github.io/aomanalyzer.io/ - Upload the problematic image to the AOM analyzer - Press 'L' to show tiles view - How many tiles (yellow rectangles) do you count
7.
by juliobbv 12d ago
> AFAIK "their choice" here is just the default Well, the default in avifenc can always be changed. Do keep in mind there's no "one size fits all" implementation, as customers desire different loading tradeoffs.
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by juliobbv 12d ago
I'm not following.... the demo involves you look at images as they get decoded. Objective benchmarks are beside the point here.
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by juliobbv 12d ago
Worth mentioning: their demo only uses two passes for progressive AVIF -- it's just their choice. You can have up to two more intermediate passes, so at 30% you can have something much closer to the original image. Even still, the demo
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by juliobbv 12d ago
Maybe you're just bad at reading text. Again, read the post carefully. Look around... nobody else had the same interpretation as you, so maybe that should clue you in something might be off with yours. The post literally goes over know
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by juliobbv 12d ago
I invite you to re-read the post carefully, with the attention it deserves. Hint: at no point the blog post says JXL will not be improved.
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by juliobbv 12d ago
Hi there! I'm Julio (co-developer of libaom and SVT-AV1's tune IQ). Here there are some points worth mentioning, because I'm catching a whiff of bad faith with your comment that honestly needs to be called out: - The inclusio
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by juliobbv 12d ago
It saddens me to see discourse on the internet about AV1's ancestry being focused on Google's VPx line of contributions, while diminishing those coming from Daala (entropy coder...) and Thor (QMs...), as well as inter-company coll
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by juliobbv 12d ago
The quick answer is: you can have up to four passes. With progressive AVIF, you let the browser avoid rendering previous passes if a subsequent one has already been downloaded. It's more efficient and saves battery.
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by juliobbv 12d ago
The quick answer is: you can have up to four passes. With progressive AVIF, you let the browser avoid rendering previous passes if a subsequent one has already been downloaded. It's more efficient and saves battery.
16.
by juliobbv 12d ago
Thanks to AV1's inter encoding, overhead is overall minimal as each pass can refine on previous ones. Think of it as a mini-video. Because of this, in the case of images with a lot of repeated patterns, progressive AVIF encoding can ac
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by juliobbv 12d ago
BTW, you can configure the AVIF encoder to have another in-between pass or two so the quality jump isn't as big. The JXL folks just happened to go with only two total passes.
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by juliobbv 12d ago
> A lower resolution image layered below the full resolution image, which is loaded and rendered first. I'm curious, where did you learn progressive AVIF works like this? Have you actually read the spec, or does your understanding c
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by juliobbv 12d ago
Progressive AVIF is very flexible: it supports up to four passes, at configurable quality and dimension scaling levels. You can have any given pass reference up to two previous ones for refinement (thanks to AV1's strong inter-encoding
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by juliobbv 1mo ago
Dude... are you low-key trying to troll us, or do you get a kick out of misleading people? How can you manage to be confidently wrong this much? It saddens me to see this kind of slop written on HN of all places, and to not have it even que
21.
by juliobbv 3mo ago
You can adjust how much "effort" the avif encoder puts on images. The default speed in libavif (-s 6 in avifenc) is fast enough, and it has been used by big CDNs to encode AVIFs for years. You can make the encoder as fast or slow
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by juliobbv 8mo ago
Especially when the a big subset of adults misunderstand of the actual scope of what "nsfw" actually consists of, and unfortunately the lgbt space isn't immune to such harmful perspectives. I've been noticing people in t
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by juliobbv 1y ago
> AVIF is better at low to medium quality, and JXL is better at medium to high quality. BTW, this is no longer true. With the introduction of tune IQ (Image Quality) to libaom and SVT-AV1, AVIF can be competitive with (and oftentimes bea
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Show HN: AvifHash v0 – Compact and efficient image placeholders(juliobbv.com)
8 points by juliobbv 2y ago|0 comments
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by juliobbv 2y ago
Sounds good! Let me know if you have any questions about SVT-AV1-PSY (I'm a developer). You can check if deltaq is being used in pictures, by opening the AVIFs in aomanalyzer ( https://pengbins.github.io/aomanalyzer.io&#
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by juliobbv 2y ago
This is cool stuff! BTW, I see that you're using `avifenc` with `aomenc` to encode AVIF, so there are few suggestions that overall increase image quality per size: - `deltaq-mode=2` or `deltaq-mode=3` each enable different flavors of v