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Disclaimer: I co-chaired the JPEG XL working group; opinions are my own. The JPEG XL format is most certainly not a nightmare internally. Compare the spec leng

by janwas 4y ago

Disclaimer: I co-chaired the JPEG XL working group; opinions are my own. The JPEG XL format is most certainly not a nightmare internally. Compare the spec lengths: 681 pages for https://aomediacodec.github.io/av1-spec/av1-spec.pdf https://aomediacodec.github.io/av1-spec/av1-spec.pdf, 101 for https://www.iso.org/standard/77977.html https://www.iso.org/standard/77977.html. Or code sizes: 6.6 MB uncompressed for libjxl (encoder+decoder), 9.5 MB for dav1d (decoder only) plus 34.2 MB for SVT-AV1 (encoder). Features such as spot colors are mostly just a matter of understanding a wide range of requirements; this particular one just boils down to an extra image layer.

cesarb 4y ago
> Compare the spec lengths: 681 pages for https://aomediacodec.github.io/av1-spec/av1-spec.pdf https://aomediacodec.github.io/av1-spec/av1-spec.pdf, 101 for https://www.iso.org/standard/77977.html https://www.iso.org/standard/77977.html. And here we immediately see one important difference between them: the first link is to a 681-page PDF, which opens immediately in my browser. The second link is to a place where one can buy access to what it says is a 101-page PDF, after paying more money than it would cost to buy a basic laptop.
- LoganDark 4y ago
  ...After seeing this, I no longer care if JXL lives or dies.
- jimis 4y ago
  > after paying more money than it would cost to buy a basic laptop No need to be imprecise, unless you are trying to push some agenda. The cost is CHF 198, which is around USD 195.
  - LoganDark 4y ago
    Yeah, a lot of things cost more than a basic laptop. Last I checked, you can get Chromebooks on the order of $20 or so per machine. That metric isn't useful to anybody.
- jonsneyers 4y ago
  That's a difference between AOM and ISO: ISO puts specs behind a paywall but anyone interested can participate in the actual standardization process through their national standardization body, AOM makes specs publicly available but participating in the standardization process costs about as much as a nice car. I don't really like either model, but I don't think I particularly prefer AOM's model.
  - derf_ 4y ago
    We created avenues for open source / community participation in AOM that did not require people to pay any money. Specifically, Mozilla sponsored the membership of VideoLAN, which in theory anyone could join, and a number of people did and do participate through that organization.
    - jonsneyers 4y ago
      That's good to know, and nice that Mozilla did that!
palotasb 4y ago
Is there a "latest draft" standard available legally and for free for wider audiences? C++, also ISO standardized, does this and I believe it has contributed greatly to its adoption and post-C++11 renaissance. See https://en.cppreference.com/w/cpp/links#C.2B.2B_Language_and_library_references https://en.cppreference.com/w/cpp/links#C.2B.2B_Language_and... . For now, JPEG XL might as well be a proprietary closed format for most hackers here.
- jonsneyers 4y ago
  Recent drafts do tend to get circulated amongst the image compression community. For wide audiences I don't think this type of document is very readable nor relevant; the number of people who are going to make their own independent implementation is relatively small. In this sense the spec audience is not quite the same as that of a spec for a programming language, which is important not just for compiler implementers but also for programmers in general. That said, I do hope that ISO will change its policy to put specs behind a paywall.
  - Mindless2112 4y ago
    Any chance of publishing the spec with ECMA in addition to ISO? The C# spec is both an ECMA and an ISO standard, but it started with ECMA.
    - jonsneyers 4y ago
      As one of the authors of the spec, I would be open to also publishing it with another standardization organization that makes specs publicly available, if the legal issues can somehow be sorted out. I think the other spec authors would also be open to that. We certainly have no desire to have a spec that is behind a paywall; that is just the way ISO operates, unfortunately.

by janwas 4y ago

cesarb 4y ago

> Compare the spec lengths: 681 pages for https://aomediacodec.github.io/av1-spec/av1-spec.pdf https://aomediacodec.github.io/av1-spec/av1-spec.pdf, 101 for https://www.iso.org/standard/77977.html https://www.iso.org/standard/77977.html. And here we immediately see one important difference between them: the first link is to a 681-page PDF, which opens immediately in my browser. The second link is to a place where one can buy access to what it says is a 101-page PDF, after paying more money than it would cost to buy a basic laptop.

LoganDark 4y ago
...After seeing this, I no longer care if JXL lives or dies.
jimis 4y ago
> after paying more money than it would cost to buy a basic laptop No need to be imprecise, unless you are trying to push some agenda. The cost is CHF 198, which is around USD 195.
- LoganDark 4y ago
  Yeah, a lot of things cost more than a basic laptop. Last I checked, you can get Chromebooks on the order of $20 or so per machine. That metric isn't useful to anybody.
jonsneyers 4y ago
That's a difference between AOM and ISO: ISO puts specs behind a paywall but anyone interested can participate in the actual standardization process through their national standardization body, AOM makes specs publicly available but participating in the standardization process costs about as much as a nice car. I don't really like either model, but I don't think I particularly prefer AOM's model.
- derf_ 4y ago
  We created avenues for open source / community participation in AOM that did not require people to pay any money. Specifically, Mozilla sponsored the membership of VideoLAN, which in theory anyone could join, and a number of people did and do participate through that organization.
  - jonsneyers 4y ago
    That's good to know, and nice that Mozilla did that!

palotasb 4y ago

Is there a "latest draft" standard available legally and for free for wider audiences? C++, also ISO standardized, does this and I believe it has contributed greatly to its adoption and post-C++11 renaissance. See https://en.cppreference.com/w/cpp/links#C.2B.2B_Language_and_library_references https://en.cppreference.com/w/cpp/links#C.2B.2B_Language_and... . For now, JPEG XL might as well be a proprietary closed format for most hackers here.

jonsneyers 4y ago
Recent drafts do tend to get circulated amongst the image compression community. For wide audiences I don't think this type of document is very readable nor relevant; the number of people who are going to make their own independent implementation is relatively small. In this sense the spec audience is not quite the same as that of a spec for a programming language, which is important not just for compiler implementers but also for programmers in general. That said, I do hope that ISO will change its policy to put specs behind a paywall.
- Mindless2112 4y ago
  Any chance of publishing the spec with ECMA in addition to ISO? The C# spec is both an ECMA and an ISO standard, but it started with ECMA.
  - jonsneyers 4y ago
    As one of the authors of the spec, I would be open to also publishing it with another standardization organization that makes specs publicly available, if the legal issues can somehow be sorted out. I think the other spec authors would also be open to that. We certainly have no desire to have a spec that is behind a paywall; that is just the way ISO operates, unfortunately.