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Is JPEG 2000 a preservation risk? (2013)

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Re: Is JPEG 2000 a preservation risk? (2013)

#12
post #5
post #2

Looks like the answer was 'yes', in something of a self-fulfilling prophecy. When was the last time you used a JPEG 2000? https://caniuse.com/jpeg2000 puts browser adoption today at 18% (!).

Are they not common in pdf documents, for example those distributed by The Internet Archive? I suspect this is why so many of them render so slowly, even on fast systems.

Yes. It's very noticeable when you're reading an ebook with J2K page images, just due to how long it takes each page to render. In contrast, regular JPEG of the same dimensions is practically instantaneous.

PDFs are probably where the majority of users will encounter J2K.

Re: Is JPEG 2000 a preservation risk? (2013)

#14
post #2

Looks like the answer was 'yes', in something of a self-fulfilling prophecy. When was the last time you used a JPEG 2000? https://caniuse.com/jpeg2000 puts browser adoption today at 18% (!).

Fun fact, whenever you go to the movies, films (that are projected digitally) are encoding in JPEG2000 (wrapped in a MXF in XYZ Colourspace). We also use it for our 3D renders for archviz, and is supported in our editing applications aswell... lower filesize compared to PNG, and better quality compared to JPG, and also supports alphas.

In other words, motion JPEG2000, and it's decoded by (no doubt extremely expensive) hardware. There's no way a general-purpose CPU can decode in realtime otherwise.

Re: Is JPEG 2000 a preservation risk? (2013)

#16
post #6

Earlier quoted context omitted.

Fun fact, whenever you go to the movies, films (that are projected digitally) are encoding in JPEG2000 (wrapped in a MXF in XYZ Colourspace). We also use it for our 3D renders for archviz, and is supported in our editing applications aswell... lower filesize compared to PNG, and better quality compared to JPG, and also supports alphas.

Do they really use straight up XYZ? Where can I read more about this format?

I think people mis-estimate file sizes these days - two hours of completely uncompressed 4K video is under 5 TB. Fits on a basic consumer external hard drive no problem. Send it by mail.

https://toolstud.io/video/filesize.php?width=3840&height=216...

Re: Is JPEG 2000 a preservation risk? (2013)

#17

I decided to use JPEG 2000 to save disk space on my photo archive a decade ago... huge mistake. [edit] I thought I had the originals backed up on CD, it turns out I didn't. DigiKam and many other programs don't support them natively. At some point I'm going to have to write a script and convert them all to normal jpegs.

I was thinking about using JPEG2000 to archive scan masters, because I hate the look of original JPEG artifacts. In the end I decided to go with FLIF to eliminate the "preservation risk" - by being lossless, I can run the output through sha256 to make sure I've gotten all the original bits back. In the event that I regret this decision, I can simply transcode and not feel too bad (as opposed to transcoding from lossless and losing even more quality).

Re: Is JPEG 2000 a preservation risk? (2013)

#18
I think a distinction needs to be made between “risk” and “potential inconvenience”.

Given that there are free, open source implementations of the JPEG 2000 decoder, There is no plausible preservation risk. Even if, in 150 years, the contemporary version of ImageMagick has dropped support for JPEG 2000, it would be relatively trivial to spin up an ancient virtual machine and run a 100-year-old version of Linux.

Or, you know, pay an intern to port some old code to whatever modern language they’re using then. Rust, probably.

Re: Is JPEG 2000 a preservation risk? (2013)

#19
post #6

Earlier quoted context omitted.

Do they really use straight up XYZ? Where can I read more about this format?

I think people mis-estimate file sizes these days - two hours of completely uncompressed 4K video is under 5 TB. Fits on a basic consumer external hard drive no problem. Send it by mail. https://toolstud.io/video/filesize.php?width=3840&height=216...

Well, two hard drives in RAID-0 if you want to play it back in real-time without copying it first to faster storage, because a single SATA drive cannot sustain 597.2MB/sec. Unless your definition of "basic consumer external hard drive" is an NVMe SSD over 10Gbps USB 3.2 or better.

Re: Is JPEG 2000 a preservation risk? (2013)

#20
post #19

Earlier quoted context omitted.

I think people mis-estimate file sizes these days - two hours of completely uncompressed 4K video is under 5 TB. Fits on a basic consumer external hard drive no problem. Send it by mail. https://toolstud.io/video/filesize.php?width=3840&height=216...

Well, two hard drives in RAID-0 if you want to play it back in real-time without copying it first to faster storage, because a single SATA drive cannot sustain 597.2MB/sec. Unless your definition of "basic consumer external hard drive" is an NVMe SSD over 10Gbps USB 3.2 or better.

As the thread says - it’s compressed. I’m giving uncompressed sizes as an upper bound.
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