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Is JPEG 2000 a preservation risk? (2013)

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

#21
There is no such thing as preservation risk for digital formats. This has been studied.

Do whatever.

The only thing that matters is publishing it in the first place and backing up on hardware that's not at preservation risk.

This is great example of fake science (Is it just "science" now?) keep the underclass constantly anxious about things that don't exist so they keep paying academics wages to do nothing but supply fear and disruption.

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

#22

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.

ImageMagick and GNU parallel happily max-out all cores on my machine and convert a few hundred images per second:

    find -type f -name '*.jp2' | parallel --xargs --max-args=1 convert {} {.}.jpg

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

#23

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.

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.

This benchmark is showing 4k decoding on commodity hardware from 2018 fast enough for movie theaters. https://www.fastcompression.com/benchmarks/decoder-benchmark...

So, presumably they could have swapped to commodity hardware a while ago.

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

#24
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.

JPEG2000 is big in medical imaging as well.

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

#25
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...

[deleted]

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

#26

> OpenJPEG C 49,892 > libjasper C 26,458 > PIL C 12,493, Python: 9,229 But does PIL actually implement any of those image formats, or is it simply wrapping other libraries in the python/c api?

The first count “PIL C” is for the C implementation of PIL including library code.

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

#27
post #3
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% (!).

There seems to be a functional and open reference implementation for JPEG 2000. https://github.com/uclouvain/openjpeg

That is mentioned in the article, along with its deficiencies.

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

#28
We're building an iPad reader app that uses Apple's PDFKit, but we encountered JPEG2000s in the PDFs of the client's library, and PDFKit doesn't render them correctly. The frustrating thing is we're stuck with the issue since it's such a niche case that I don't think Apple will ever fix it. There is a 3rd-party commercial library PSPDF for iOS that renders it right, but I don't think they want to pay for it.

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

#29

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, y…

The article addresses this. The open source implementations are not complete so there are compliant files they cannot render. Also they have rendering bugs which mean some content does not render properly, and worse some files they generate render fine now, but are not compliant and if the code is fixed those portions of the files may stop rendering correctly. Some of these issues only manifest at particular zoom levels, so you are never be sure what you are seeing is correct. This us all part of the problem with the spec being so complex.

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

#30

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.

Why was it a huge mistake? There are decent libraries that support it. Did it just not work with your cloud setup or OS libraries?

Check the article’s discussion of rendering bugs and implementation incompatibilities.
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