On: Google unkills JPEG XL?

[m348e912]

A full-resolution, maximum-size JPEG XL image (1,073,741,823 × 1,073,741,824):

Uncompressed: 3.5–7 exabytes Realistically compressed: Tens to hundreds of petabytes

Thats a serious high-res image

[xnorswap → m348e912]

At 600DPI that's over a marathon in each dimension.

I do wonder if there are any DOS vectors that need to be considered if such a large image can be defined in relatively small byte space.

I was going to work out how many A4 pages that was to print, but google's magic calculator that worked really well has been replaced by Gemini which produces this trash:

    Number of A4 pages=0.0625 square meters per A4 page * 784 square miles   =13,200 A4 pages.

No Gemini, you can't equate meters and miles, even if they do both abbreviate to 'm' sometimes.

[threeducks → xnorswap]

> I do wonder if there are any DOS vectors that need to be considered if such a large image can be defined in relatively small byte space.

You can already DOS with SVG images. Usually, the browser tab crashes before worse things happen. Most sites therefore do not allow SVG uploads, except GitHub for some reason.

[Intralexical → xnorswap]

"Google's magic calculator" was probably just a wrapper to GNU Units [0], which produces:

  $ units
  You have: (1073741823/(600/inch))**2 / A4paper  
  You want:  
         Definition: 3.312752e+10

Equivalent tools: Qalc, Numbat

0: https://news.ycombinator.com/item?id=36994418

[fwip → xnorswap]

Wolfram alpha is the better calculator for that sort of thing.

[yread → m348e912]

The only practical way to work with such large images is if they are tiled and pyramidal anyway

[Magnap → yread]

Which JXL supports, by the way. Tiling is mandatory for images bigger than 2048x2048, and you can construct images based on an 8x downscaled version, recursing that up to 4 times for up to 4096x downscaling.

[Akronymus → yread]

what does pyramidal mean in this context?

[scheme271 → Akronymus]

Probably, multiple resolutions of the same thing. E.g. a lower res image of the entire scene and then higher resolution versions of sections. As you zoom in, the higher resolution versions get used so that you can see more detail while limiting memory consumption.

[jjcob → Akronymus]

I think it means encoded in such a way that you first have low res version, then higher res versions, then even higher res versions etc.

[shadowgovt → Akronymus]

Replicated at different resolutions depending on your zoom level.

One patch at low resolution is backed by four higher-resolution images, each of which is backed by four higher-resolution images, and so on... All on top of an index to fetch the right images for your zoom level and camera position.

[jjk7 → Akronymus]

Tiled at different zoom levels

[wang_li → yread]

We call those mipmaps.

[flir → m348e912]

An image of earth at very roughly 4cmx4cm resolution? (If I've knocked the zero's off correctly)

[cubefox → m348e912]

Yes, but unlike AVIF, JPEG XL supports progressive decoding, so you can see the picture in lower quality long before the download has finished. (Ordinary JPEG also supports progressive decoding, but in a much less efficient manner, which means you have to wait longer for previews with lower quality.)

[tyre → cubefox]

I don’t think the issue with the exabyte image is progressive decoding, though it would at least get you an image of what is bringing down your machine while you wait for the inevitable!

[westmeal → mcdonje]

They still down voted anyway lol

[mcdonje → westmeal]

At least I didn't give Dang extra work.

[westmeal → mcdonje]

Lol yeah Dang has a lot of flame wars to deal with