this post was submitted on 02 Sep 2024
219 points (98.2% liked)

Programming

17547 readers
52 users here now

Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!

Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.

Hope you enjoy the instance!

Rules

Rules

  • Follow the programming.dev instance rules
  • Keep content related to programming in some way
  • If you're posting long videos try to add in some form of tldr for those who don't want to watch videos

Wormhole

Follow the wormhole through a path of communities [email protected]



founded 2 years ago
MODERATORS
 

There are a couple I have in mind. Like many techies, I am a huge fan of RSS for content distribution and XMPP for federated communication.

The really niche one I like is S-expressions as a data format and configuration in place of json, yaml, toml, etc.

I am a big fan of Plaintext formats, although I wish markdown had a few more features like tables.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 56 points 2 months ago (2 children)
  • Existing JPEG files (which are the vast, vast majority of images currently on the web and in people's own libraries/catalogs) can be losslessly compressed even further with zero loss of quality. This alone means that there's benefits to adoption, if nothing else for archival and serving old stuff.
  • JPEG XL encoding and decoding is much, much faster than pretty much any other format.
  • The format works for both lossy and lossless compression, depending on the use case and need. Photographs can be encoded in a lossy way much more efficiently than JPEG and things like screenshots can be losslessly encoded more efficiently than PNG.
  • The format anticipates being useful for both screen and prints. Webp, HEIF, and AVIF are all optimized for screen resolutions, and fail at truly high resolution uses appropriate for prints. The JPEG XL format isn't ready to replace camera RAW files, but there's room in the spec to accommodate that use case, too.

It's great and should be adopted everywhere, to replace every raster format from JPEG photographs to animated GIFs (or the more modern live photos format with full color depth in moving pictures) to PNGs to scanned TIFFs with zero compression/loss.

[–] [email protected] 8 points 2 months ago* (last edited 2 months ago)

Existing JPEG files (which are the vast, vast majority of images currently on the web and in people’s own libraries/catalogs) can be losslessly compressed even further with zero loss of quality. This alone means that there’s benefits to adoption, if nothing else for archival and serving old stuff.

Funny thing is, there was talk on the Chrome bug tracker of using just this ability transparently at the HTTP layer (like gzip/brotli compression), but they're so set on pushing their AVIF format that they backed away from it.

[–] [email protected] 7 points 2 months ago (2 children)
  • The format works for both lossy and lossless compression, depending on the use case and need. Photographs can be encoded in a lossy way much more efficiently than JPEG and things like screenshots can be losslessly encoded more efficiently than PNG.

Someone made a fair point that having a format being both lossy and lossless is not necessarily a great idea. If you download a jpeg file you know it will be compressed, if you download png it will be lossless. Shifting through jxl files to check if it's lossy or not doesn't sound very fun.

All in all I'm a big supporter of jxl though, it's one of the only github repos I actively follow.

[–] [email protected] 10 points 2 months ago

While I agree that it's somewhat bad that there is no distinction between lossless and lossy jxl in the file extension, I think it's really not a big deal compared to the present situation with jpg/png.

The reason being that if you download a png file you have no idea if its been converted from jpg, if it's a screenshot of a jpg, or if it's been subjected to lossy reencoding by a tool or a website upload process.

The only thing you can really do to try and see if the file you've downloaded has suffered encoding loss is to do an image search on it and see if there are any better quality versions out there. You'd do the exact same thing with a jxl file.

[–] [email protected] 4 points 2 months ago

Functionally speaking, I don't see this as a significant issue.

JPEG quality settings can run a pretty wide gamut, and obviously wouldn't be immediately apparent without viewing the file and analyzing the metadata. But if we're looking at metadata, JPEG XL reports that stuff, too.

Of course, the metadata might only report the most recent conversion, but that's still a problem with all image formats, where conversion between GIF/PNG/JPG, or even edits to JPGs, would likely create lots of artifacts even if the last step happens to be lossless.

You're right that we should ensure that the metadata does accurately describe whether an image has ever been encoded in a lossy manner, though. It's especially important for things like medical scans where every pixel matters, and needs to be trusted as coming from the sensor rather than an artifact of the encoding process, to eliminate some types of error. That's why I'm hopeful that a full JXL based workflow for those images will preserve the details when necessary, and give fewer opportunities for that type of silent/unknown loss of data to occur.